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Sample records for mexican axolotl proceedings

  1. The Mexican Axolotl in Schools

    Science.gov (United States)

    Thomas, R. M.

    1976-01-01

    Suggests and describes laboratory activities in which the Mexican axolotl (Ambystoma mexicanum Shaw) is used, including experiments in embryology and early development, growth and regeneration, neoteny and metamorphosis, genetics and coloration, anatomy and physiology, and behavior. Discusses care and maintenance of animals. (CS)

  2. Housing and maintenance of Ambystoma mexicanum, the Mexican axolotl.

    Science.gov (United States)

    Farkas, Johanna E; Monaghan, James R

    2015-01-01

    The aim of this paper is to assemble a significant amount of information on Ambystoma mexicanum, the axolotl salamander, to assist in the basic knowledge needed to raise, breed, and study most aspects of axolotl biology. It is important to understand the basic biology of the axolotl in order to make informed decisions on their proper care and use in experiments. Therefore, we will provide necessary information to the non-herpetologist that will assist in their study of this unique and fascinating animal. We also aim to provide a resource on the general anatomy, behavior, and experimental tips specific to the Mexican axolotl that will be of use to most axolotl laboratories. Axolotls have been actively researched since the 1860s, giving testament to their relatively straightforward maintenance and their versatility as an animal model for development and regeneration. Interest in using the axolotl in laboratory research has grown tremendously over the past decade, so dedicated resources to support the study of this species are needed and encouraged.

  3. Resegmentation in the Mexican axolotl, Ambystoma mexicanum.

    Science.gov (United States)

    Piekarski, Nadine; Olsson, Lennart

    2014-02-01

    The segmental series of somites in the vertebrate embryo gives rise to the axial skeleton. In amniote models, single vertebrae are derived from the sclerotome of two adjacent somites. This process, known as resegmentation, is well-studied using the quail-chick chimeric system, but the presumed generality of resegmentation across vertebrates remains poorly evaluated. Resegmentation has been questioned in anamniotes, given that the sclerotome is much smaller and lacks obvious differentiation between cranial and caudal portions. Here, we provide the first experimental evidence that resegmentation does occur in a species of amphibian. Fate mapping of individual somites in the Mexican axolotl (Ambystoma mexicanum) revealed that individual vertebrae receive cells from two adjacent somites as in the chicken. These findings suggest that large size and segmentation of the sclerotome into distinct cranial and caudal portions are not requirements for resegmentation. Our results, in addition to those for zebrafish, indicate that resegmentation is a general process in building the vertebral column in vertebrates, although it may be achieved in different ways in different groups. Copyright © 2013 Wiley Periodicals, Inc.

  4. An introduction to the Mexican axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Gresens, Jill

    2004-10-01

    A number of unusual traits, including a remarkable capacity for wound healing and limb regeneration, make the axolotl an interesting animal model. The author provides an overview of axolotl care and use in biomedical research.

  5. Forever young: Endocrinology of paedomorphosis in the Mexican axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    De Groef, Bert; Grommen, Sylvia V H; Darras, Veerle M

    2018-05-16

    The Mexican axolotl (Ambystoma mexicanum) is a salamander species that does not undergo metamorphosis, resulting in the retention of juvenile characteristics in the mature breeding stage (paedomorphosis). Here we review the endocrinological studies investigating the proximate cause of axolotl paedomorphosis with a focus on the hypothalamo-pituitary-thyroid (HPT) axis. It is well established that axolotl paedomorphosis is a consequence of low activity of the HPT axis. The pituitary hormone thyrotropin (TSH) is capable of inducing metamorphosis in the axolotl, which indicates that all processes and interactions in the HPT axis below the pituitary level are functional, but that TSH release is impaired. In metamorphosing species, TSH secretion is largely controlled by the hypothalamic neuropeptide corticotropin-releasing hormone (CRH), which seems to have lost its thyrotropic activity in the axolotl. However, preliminary experiments have not yet confirmed a role for faulty CRH signalling in axolotl paedomorphosis. Other hypothalamic factors and potential pituitary inhibitors need to be investigated to identify their roles in amphibian metamorphosis and axolotl paedomorphosis. Copyright © 2018 Elsevier Inc. All rights reserved.

  6. Role of Myofibril-Inducing RNA in cardiac TnT expression in developing Mexican axolotl

    Science.gov (United States)

    Sferrazza, Gian-Franco; Zhang, Chi; Jia, Pingping; Lemanski, Sharon L.; Athauda, Gagani; Stassi, Alyssa; Halager, Kristine; Maier, Jennifer A.; Rueda-de-Leon, Elena; Gupta, Amit; Dube, Syamalima; Huang, Xupei; Prentice, Howard M.; Dube, Dipak K.; Lemanski, Larry F.

    2007-01-01

    The Mexican axolotl, Ambystoma mexicanum, has been a useful animal model to study heart development and cardiac myofibrillogenesis. A naturally-occurring recessive mutant, gene “c”, for cardiac non-function in the Mexican axolotl causes a failure of myofibrillogenesis due to a lack of tropomyosin expression in homozygous mutant (c/c) embryonic hearts.. Myofibril-Inducing RNA (MIR) rescues mutant hearts in vitro by promoting tropomyosin expression and myofibril formation thereafter. We have studied the effect of MIR on the expression of various isoforms of cardiac Troponin-T (cTnT), a component of the thin filament that binds with tropomyosin. Four alternatively spliced cTnT isoforms have been characterized from developing axolotl heart. The expression of various cTnT isoforms in normal, mutant, and mutant hearts corrected with MIR, is evaluated by real-time RT-PCR using isoform specific primer pairs; MIR affects the total transcription as well as the splicing of the cTnT in axolotl heart PMID:17408593

  7. Activation of germline-specific genes is required for limb regeneration in the Mexican axolotl

    OpenAIRE

    Zhu, Wei; Pao, Gerald M; Satoh, Akira; Cummings, Gillian; Monaghan, James R; Harkins, Timothy T; Bryant, Susan V; Voss, S Randal; Gardiner, David M; Hunter, Tony

    2012-01-01

    The capacity for tissue and organ regeneration in humans is dwarfed by comparison to that of salamanders. Emerging evidence suggests that mechanisms learned from the early phase of salamander limb regeneration-wound healing, cellular dedifferentiation and blastemal formation-will reveal therapeutic approaches for tissue regeneration in humans. Here we describe a unique transcriptional fingerprint of regenerating limb tissue in the Mexican axolotl (Ambystoma mexicanum) that is indicative of ce...

  8. Identification of Conserved and Novel MicroRNAs during Tail Regeneration in the Mexican Axolotl

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    Micah D. Gearhart

    2015-09-01

    Full Text Available The Mexican axolotl salamander (Ambystoma mexicanum is one member of a select group of vertebrate animals that have retained the amazing ability to regenerate multiple body parts. In addition to being an important model system for regeneration, the axolotl has also contributed extensively to studies of basic development. While many genes known to play key roles during development have now been implicated in various forms of regeneration, much of the regulatory apparatus controlling the underlying molecular circuitry remains unknown. In recent years, microRNAs have been identified as key regulators of gene expression during development, in many diseases and also, increasingly, in regeneration. Here, we have used deep sequencing combined with qRT-PCR to undertake a comprehensive identification of microRNAs involved in regulating regeneration in the axolotl. Specifically, among the microRNAs that we have found to be expressed in axolotl tissues, we have identified 4564 microRNA families known to be widely conserved among vertebrates, as well as 59,811 reads of putative novel microRNAs. These findings support the hypothesis that microRNAs play key roles in managing the precise spatial and temporal patterns of gene expression that ensures the correct regeneration of missing tissues.

  9. Regulation of antibody synthesis in the X-irradiated Mexican axolotl

    International Nuclear Information System (INIS)

    Charlemagne, J.

    1981-01-01

    The effects of X-irradiation were studied on the Mexican axolotl antibody synthesis. To reduce the anti-horse red blood cell (HRBC) antibody titers, 150 rd and smaller doses are ineffective, 200-450 rd are increasingly effective, and 700 rd are maximally effective (and lethal). A significant enhancement of the anti-HRBC titers was observed in low doses (50-150 rd X-irradiated animals). This enhancement was also observed when a low X-ray dose was applied only on the thymic areas. In whole body, but thymus area-shielded, 100 rd X-irradiated animals, the anti-HRBC titers were similar to those of the nonirradiated, HRBC-immunized control group. To explain these phenomena, it is suggested that a radiosensitive, adult thymectomy-sensitive and hydrocortisone-sensitive suppressor T cell subpopulation regulates the antibody synthesis in the axolotl. (orig.) [de

  10. Regulation of antibody synthesis in the X-irradiated Mexican axolotl

    Energy Technology Data Exchange (ETDEWEB)

    Charlemagne, J.

    1981-09-01

    The effects of X-irradiation were studied on the Mexican axolotl antibody synthesis. To reduce the anti-horse red blood cell (HRBC) antibody titers, 150 rd and smaller doses are ineffective, 200-450 rd are increasingly effective, and 700 rd are maximally effective (and lethal). A significant enhancement of the anti-HRBC titers was observed in low doses (50-150 rd X-irradiated animals). This enhancement was also observed when a low X-ray dose was applied only on the thymic areas. In whole body, but thymus area-shielded, 100 rd X-irradiated animals, the anti-HRBC titers were similar to those of the nonirradiated, HRBC-immunized control group. To explain these phenomena, it is suggested that a radiosensitive, adult thymectomy-sensitive and hydrocortisone-sensitive suppressor T cell subpopulation regulates the antibody synthesis in the axolotl.

  11. Evaluation of the anesthetic effects of MS222 in the adult Mexican axolotl (Ambystoma mexicanum

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    Zullian C

    2016-01-01

    Full Text Available Chiara Zullian,1 Aurore Dodelet-Devillers,1 Stéphane Roy,2 Pascal Vachon1 1Département de Biomédecine Vétérinaire, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, 2Département de Stomatologie, Faculté de Médecine Dentaire, Montréal, Québec, Canada Abstract: The Mexican axolotl (Ambystoma mexicanum is a unique research model in several fields of medicine, where surgical and invasive procedures may be required. As yet, little is known about the efficacy of MS222 (tricaine methanesulfonate, which is the most commonly used anesthetic agent in amphibians. The main objectives of this study were to evaluate the anesthetic effects and physiological changes in adult axolotls following a 20-minute immersion bath, containing progressive MS222 concentrations starting at 0.1%. Depth of anesthesia and physiological changes were evaluated every 15 minutes post-MS222 exposure with the following parameters: righting behavior, withdrawal reflex, acetic acid test response, heart rate, and blood oxygen saturation, as well as cloacal and body surface temperatures. A 20-minute exposure in a 0.1% MS222 immersion bath (n=6 animals had no anesthetic effects on adult axolotls after 20 minutes of exposure. With a 0.2% MS222 solution, all axolotls (n=9 were deeply anesthetized at 15 minutes, and 80% were still unresponsive at 30 minutes postexposure. Blood oxygen saturation and heart rate were slightly, but significantly, increased when compared with the baseline value and remained stable up to recovery. There was no significant increase in surface and cloaca temperatures, compared with baseline. With the 0.4% MS222 solution, the duration of anesthesia lasted for 90 minutes to at least 120 minutes (n=3 animals and this concentration was deemed too high. In conclusion, a 20-minute immersion bath with 0.2% MS222 may be used for short procedures (15–30 minutes requiring anesthesia of adult axolotls. Keywords: Ambystoma mexicanum

  12. Highly restricted diversity of TCR delta chains of the amphibian Mexican axolotl (Ambystoma mexicanum) in peripheral tissues.

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    André, Sébastien; Kerfourn, Fabienne; Affaticati, Pierre; Guerci, Aline; Ravassard, Philippe; Fellah, Julien S

    2007-06-01

    Gammadelta T cells localize at mammalian epithelial surfaces to exert both protective and regulatory roles in response to infections. We have previously characterized the Mexican axolotl (Ambystoma mexicanum) T cell receptor delta (TRD) chain. In this study, TRD repertoires in spleen, liver, intestine and skin from larvae, pre-adult and adult axolotls were examined and compared to the thymic TRD repertoire. A TRDV transcript without N/D diversity, TRDV1S1-TRDJ1, dominates the TRD repertoires until sexual maturation. In adult tissues, this canonical transcript is replaced by another dominant TRDV1S1-TRDJ1 transcript. In the thymus, these two transcripts are detected early in development. Our results suggest that gammadelta T cells that express the canonical TRDV1S1-TRDJ1 transcript emerge from the thymus and colonize the peripheral tissues, where they are selectively expanded by recurrent ligands. This particular situation is probably related to the neotenic state and the slow development of the axolotl. In thymectomized axolotls, TRD repertoires appear different from those of normal axolotls, suggesting that extrathymic gammadelta T cell differentiation could occur. Gene expression analysis showed the importance of the gut in T cell development.

  13. Molecular and immunohistochemical analyses of cardiac troponin T during cardiac development in the Mexican axolotl, Ambystoma mexicanum.

    Science.gov (United States)

    Zhang, C; Pietras, K M; Sferrazza, G F; Jia, P; Athauda, G; Rueda-de-Leon, E; Rveda-de-Leon, E; Maier, J A; Dube, D K; Lemanski, S L; Lemanski, L F

    2007-01-01

    The Mexican axolotl, Ambystoma mexicanum, is an excellent animal model for studying heart development because it carries a naturally occurring recessive genetic mutation, designated gene c, for cardiac nonfunction. The double recessive mutants (c/c) fail to form organized myofibrils in the cardiac myoblasts resulting in hearts that fail to beat. Tropomyosin expression patterns have been studied in detail and show dramatically decreased expression in the hearts of homozygous mutant embryos. Because of the direct interaction between tropomyosin and troponin T (TnT), and the crucial functions of TnT in the regulation of striated muscle contraction, we have expanded our studies on this animal model to characterize the expression of the TnT gene in cardiac muscle throughout normal axolotl development as well as in mutant axolotls. In addition, we have succeeded in cloning the full-length cardiac troponin T (cTnT) cDNA from axolotl hearts. Confocal microscopy has shown a substantial, but reduced, expression of TnT protein in the mutant hearts when compared to normal during embryonic development. 2006 Wiley-Liss, Inc.

  14. Activation of germline-specific genes is required for limb regeneration in the Mexican axolotl

    Science.gov (United States)

    Zhu, Wei; Pao, Gerald M; Satoh, Akira; Cummings, Gillian; Monaghan, James R; Harkins, Timothy T; Bryant, Susan V; Voss, S Randal; Gardiner, David M; Hunter, Tony

    2013-01-01

    The capacity for tissue and organ regeneration in humans is dwarfed by comparison to that of salamanders. Emerging evidence suggests that mechanisms learned from the early phase of salamander limb regeneration – wound healing, cellular dedifferentiation and blastemal formation – will reveal therapeutic approaches for tissue regeneration in humans. Here we describe a unique transcriptional fingerprint of regenerating limb tissue in the Mexican axolotl (Ambystoma mexicanum) that is indicative of cellular reprogramming of differentiated cells to a germline-like state. Two genes that are required for self-renewal of germ cells in mice and flies, Piwi-like 1 (PL1) and Piwi-like 2 (PL2), are expressed in limb blastemal cells, the basal layer keratinocytes and the thickened apical epithelial cap in the wound epidermis in the regenerating limb. Depletion of PL1 and PL2 by morpholino oligonucleotides decreased cell proliferation and increased cell death in the blastema leading to a significant retardation of regeneration. Examination of key molecules that are known to be required for limb development or regeneration further revealed that FGF8 is transcriptionally downregulated in the presence of the morpholino oligos, indicating PL1 and PL2 might participate in FGF signaling during limb regeneration. Given the requirement for FGF signaling in limb development and regeneration, the results suggest that PL1 and PL2 function to establish a unique germline-like state that is associated with successful regeneration. PMID:22841627

  15. Patterns of spatial and temporal visceral arch muscle development in the Mexican axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Ericsson, Rolf; Olsson, Lennart

    2004-08-01

    Vertebrate head development is a classical topic that has received renewed attention during the last decade. Most reports use one of a few model organisms (chicken, mouse, zebrafish) and have focused on molecular mechanisms and the role of the neural crest, while cranial muscle development has received less attention. Here we describe cranial muscle differentiation and morphogenesis in the Mexican axolotl, Ambystoma mexicanum. To determine the onset of differentiation we use antibodies against desmin and optical sectioning using confocal laser scanning microscopy on whole-mount immunostained embryos. This technique makes it possible to document the cranial muscle in three dimensions while keeping the specimens intact. Desmin expression starts almost simultaneously in the first, second, and third visceral arch muscles (as in other amphibians studied). Muscle anlagen divide up early into the different elements which constitute the larval cranial musculature. We extend and refine earlier findings, e.g., by documenting a clear division between interhyoideus and interhyoideus posterior. The timing of cranial muscle differentiation differs among vertebrate groups, but seems to be constant within each group. This study provides a morphological foundation for further studies of muscle cell fate and early differentiation. Copyright 2004 Wiley-Liss, Inc.

  16. Using Ambystoma mexicanum (Mexican axolotl) embryos, chemical genetics, and microarray analysis to identify signaling pathways associated with tissue regeneration.

    Science.gov (United States)

    Ponomareva, Larissa V; Athippozhy, Antony; Thorson, Jon S; Voss, S Randal

    2015-12-01

    Amphibian vertebrates are important models in regenerative biology because they present exceptional regenerative capabilities throughout life. However, it takes considerable effort to rear amphibians to juvenile and adult stages for regeneration studies, and the relatively large sizes that frogs and salamanders achieve during development make them difficult to use in chemical screens. Here, we introduce a new tail regeneration model using late stage Mexican axolotl embryos. We show that axolotl embryos completely regenerate amputated tails in 7days before they exhaust their yolk supply and begin to feed. Further, we show that axolotl embryos can be efficiently reared in microtiter plates to achieve moderate throughput screening of soluble chemicals to investigate toxicity and identify molecules that alter regenerative outcome. As proof of principle, we identified integration 1 / wingless (Wnt), transforming growth factor beta (Tgf-β), and fibroblast growth factor (Fgf) pathway antagonists that completely block tail regeneration and additional chemicals that significantly affected tail outgrowth. Furthermore, we used microarray analysis to show that inhibition of Wnt signaling broadly affects transcription of genes associated with Wnt, Fgf, Tgf-β, epidermal growth factor (Egf), Notch, nerve growth factor (Ngf), homeotic gene (Hox), rat sarcoma/mitogen-activated protein kinase (Ras/Mapk), myelocytomatosis viral oncogene (Myc), tumor protein 53 (p53), and retinoic acid (RA) pathways. Punctuated changes in the expression of genes known to regulate vertebrate development were observed; this suggests the tail regeneration transcriptional program is hierarchically structured and temporally ordered. Our study establishes the axolotl as a chemical screening model to investigate signaling pathways associated with tissue regeneration. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Effect of thyroid hormone concentration on the transcriptional response underlying induced metamorphosis in the Mexican axolotl (Ambystoma

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    Samuels Amy K

    2008-02-01

    Full Text Available Abstract Background Thyroid hormones (TH induce gene expression programs that orchestrate amphibian metamorphosis. In contrast to anurans, many salamanders do not undergo metamorphosis in nature. However, they can be induced to undergo metamorphosis via exposure to thyroxine (T4. We induced metamorphosis in juvenile Mexican axolotls (Ambystoma mexicanum using 5 and 50 nM T4, collected epidermal tissue from the head at four time points (Days 0, 2, 12, 28, and used microarray analysis to quantify mRNA abundances. Results Individuals reared in the higher T4 concentration initiated morphological and transcriptional changes earlier and completed metamorphosis by Day 28. In contrast, initiation of metamorphosis was delayed in the lower T4 concentration and none of the individuals completed metamorphosis by Day 28. We identified 402 genes that were statistically differentially expressed by ≥ two-fold between T4 treatments at one or more non-Day 0 sampling times. To complement this analysis, we used linear and quadratic regression to identify 542 and 709 genes that were differentially expressed by ≥ two-fold in the 5 and 50 nM T4 treatments, respectively. Conclusion We found that T4 concentration affected the timing of gene expression and the shape of temporal gene expression profiles. However, essentially all of the identified genes were similarly affected by 5 and 50 nM T4. We discuss genes and biological processes that appear to be common to salamander and anuran metamorphosis, and also highlight clear transcriptional differences. Our results show that gene expression in axolotls is diverse and precise, and that axolotls provide new insights about amphibian metamorphosis.

  18. Effect of thyroid hormone concentration on the transcriptional response underlying induced metamorphosis in the Mexican axolotl (Ambystoma).

    Science.gov (United States)

    Page, Robert B; Voss, Stephen R; Samuels, Amy K; Smith, Jeramiah J; Putta, Srikrishna; Beachy, Christopher K

    2008-02-11

    Thyroid hormones (TH) induce gene expression programs that orchestrate amphibian metamorphosis. In contrast to anurans, many salamanders do not undergo metamorphosis in nature. However, they can be induced to undergo metamorphosis via exposure to thyroxine (T4). We induced metamorphosis in juvenile Mexican axolotls (Ambystoma mexicanum) using 5 and 50 nM T4, collected epidermal tissue from the head at four time points (Days 0, 2, 12, 28), and used microarray analysis to quantify mRNA abundances. Individuals reared in the higher T4 concentration initiated morphological and transcriptional changes earlier and completed metamorphosis by Day 28. In contrast, initiation of metamorphosis was delayed in the lower T4 concentration and none of the individuals completed metamorphosis by Day 28. We identified 402 genes that were statistically differentially expressed by > or = two-fold between T4 treatments at one or more non-Day 0 sampling times. To complement this analysis, we used linear and quadratic regression to identify 542 and 709 genes that were differentially expressed by > or = two-fold in the 5 and 50 nM T4 treatments, respectively. We found that T4 concentration affected the timing of gene expression and the shape of temporal gene expression profiles. However, essentially all of the identified genes were similarly affected by 5 and 50 nM T4. We discuss genes and biological processes that appear to be common to salamander and anuran metamorphosis, and also highlight clear transcriptional differences. Our results show that gene expression in axolotls is diverse and precise, and that axolotls provide new insights about amphibian metamorphosis.

  19. Courtship Pheromone Use in a Model Urodele, the Mexican Axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Maex, Margo; Van Bocxlaer, Ines; Mortier, Anneleen; Proost, Paul; Bossuyt, Franky

    2016-02-04

    Sex pheromones have been shown to constitute a crucial aspect of salamander reproduction. Until now, courtship pheromones of Salamandridae and Plethodontidae have been intensively studied, but information on chemical communication in other urodelan families is essentially lacking. The axolotl (Ambystoma mexicanum, Ambystomatidae) has a courtship display that suggests a key role for chemical communication in the orchestration of its sexual behavior, but no sex pheromones have yet been characterized from this species. Here we combined whole transcriptome analyses of the male cloaca with proteomic analyses of water in which axolotls were allowed to court to show that male axolotls secrete multiple ca. 20 kDa glycosylated sodefrin precursor-like factor (SPF) proteins during courtship. In combination with phylogenetic analyses, our data show that the male cloaca essentially secretes a courtship-specific clade of SPF proteins that is orthologous to salamandrid courtship pheromones. In addition, we identified an SPF protein for which no orthologs have been described from other salamanders so far. Overall, our study advocates a central role for SPF proteins during the courtship display of axolotls and adds knowledge on pheromone use in a previously unexplored deep evolutionary branch of salamander evolution.

  20. Role of cranial neural crest cells in visceral arch muscle positioning and morphogenesis in the Mexican axolotl, Ambystoma mexicanum.

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    Ericsson, Rolf; Cerny, Robert; Falck, Pierre; Olsson, Lennart

    2004-10-01

    The role of cranial neural crest cells in the formation of visceral arch musculature was investigated in the Mexican axolotl, Ambystoma mexicanum. DiI (1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine, perchlorate) labeling and green fluorescent protein (GFP) mRNA injections combined with unilateral transplantations of neural folds showed that neural crest cells contribute to the connective tissues but not the myofibers of developing visceral arch muscles in the mandibular, hyoid, and branchial arches. Extirpations of individual cranial neural crest streams demonstrated that neural crest cells are necessary for correct morphogenesis of visceral arch muscles. These do, however, initially develop in their proper positions also in the absence of cranial neural crest. Visceral arch muscles forming in the absence of neural crest cells start to differentiate at their origins but fail to extend toward their insertions and may have a frayed appearance. Our data indicate that visceral arch muscle positioning is controlled by factors that do not have a neural crest origin. We suggest that the cranial neural crest-derived connective tissues provide directional guidance important for the proper extension of the cranial muscles and the subsequent attachment to the insertion on the correct cartilage. In a comparative context, our data from the Mexican axolotl support the view that the cranial neural crest plays a fundamental role in the development of not only the skeleton of the vertebrate head but also in the morphogenesis of the cranial muscles and that this might be a primitive feature of cranial development in vertebrates. 2004 Wiley-Liss, Inc.

  1. Probability of Regenerating a Normal Limb After Bite Injury in the Mexican Axolotl (Ambystoma mexicanum).

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    Thompson, Sierra; Muzinic, Laura; Muzinic, Christopher; Niemiller, Matthew L; Voss, S Randal

    2014-06-01

    Multiple factors are thought to cause limb abnormalities in amphibian populations by altering processes of limb development and regeneration. We examined adult and juvenile axolotls ( Ambystoma mexicanum ) in the Ambystoma Genetic Stock Center (AGSC) for limb and digit abnormalities to investigate the probability of normal regeneration after bite injury. We observed that 80% of larval salamanders show evidence of bite injury at the time of transition from group housing to solitary housing. Among 717 adult axolotls that were surveyed, which included solitary-housed males and group-housed females, approximately half presented abnormalities, including examples of extra or missing digits and limbs, fused digits, and digits growing from atypical anatomical positions. Bite injury likely explains these limb defects, and not abnormal development, because limbs with normal anatomy regenerated after performing rostral amputations. We infer that only 43% of AGSC larvae will present four anatomically normal looking adult limbs after incurring a bite injury. Our results show regeneration of normal limb anatomy to be less than perfect after bite injury.

  2. Identification of Differentially Expressed Thyroid Hormone Responsive Genes from the Brain of the Mexican Axolotl (Ambystoma mexicanum) ✧

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    Huggins, P; Johnson, CK; Schoergendorfer, A; Putta, S; Bathke, AC; Stromberg, AJ; Voss, SR

    2011-01-01

    The Mexican axolotl (Ambystoma mexicanum) presents an excellent model to investigate mechanisms of brain development that are conserved among vertebrates. In particular, metamorphic changes of the brain can be induced in free-living aquatic juveniles and adults by simply adding thyroid hormone (T4) to rearing water. Whole brains were sampled from juvenile A. mexicanum that were exposed to 0, 8, and 18 days of 50 nM T4, and these were used to isolate RNA and make normalized cDNA libraries for 454 DNA sequencing. A total of 1,875,732 high quality cDNA reads were assembled with existing ESTs to obtain 5,884 new contigs for human RefSeq protein models, and to develop a custom Affymetrix gene expression array (Amby_002) with approximately 20,000 probe sets. The Amby_002 array was used to identify 303 transcripts that differed statistically (p 1.5) as a function of days of T4 treatment. Further statistical analyses showed that Amby_002 performed concordantly in comparison to an existing, small format expression array. This study introduces a new A. mexicanum microarray resource for the community and the first lists of T4-responsive genes from the brain of a salamander amphibian. PMID:21457787

  3. Identification of differentially expressed thyroid hormone responsive genes from the brain of the Mexican Axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Huggins, P; Johnson, C K; Schoergendorfer, A; Putta, S; Bathke, A C; Stromberg, A J; Voss, S R

    2012-01-01

    The Mexican axolotl (Ambystoma mexicanum) presents an excellent model to investigate mechanisms of brain development that are conserved among vertebrates. In particular, metamorphic changes of the brain can be induced in free-living aquatic juveniles and adults by simply adding thyroid hormone (T4) to rearing water. Whole brains were sampled from juvenile A. mexicanum that were exposed to 0, 8, and 18 days of 50 nM T4, and these were used to isolate RNA and make normalized cDNA libraries for 454 DNA sequencing. A total of 1,875,732 high quality cDNA reads were assembled with existing ESTs to obtain 5884 new contigs for human RefSeq protein models, and to develop a custom Affymetrix gene expression array (Amby_002) with approximately 20,000 probe sets. The Amby_002 array was used to identify 303 transcripts that differed statistically (p1.5) as a function of days of T4 treatment. Further statistical analyses showed that Amby_002 performed concordantly in comparison to an existing, small format expression array. This study introduces a new A. mexicanum microarray resource for the community and the first lists of T4-responsive genes from the brain of a salamander amphibian. Copyright © 2011 Elsevier Inc. All rights reserved.

  4. Muscular derivatives of the cranialmost somites revealed by long-term fate mapping in the Mexican axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Piekarski, Nadine; Olsson, Lennart

    2007-01-01

    The fate of single somites has not been analyzed from a comparative perspective with modern cell-marking methods. Most of what we know is based on work using quail-chick chimeras. Consequently, to what degree cell fate has been conserved despite the anatomical differences among vertebrates is unknown. We have analyzed the cell fate of the cranialmost somites, with the focus on somite two, in the Mexican axolotl (Ambystoma mexicanum). Somite cells were marked by injection of dextran-fluorescein and detected using immunofluorescence after 2 months of development in paraffin sections. Our data confirm and extend earlier studies based on classical histology in salamanders. We show that somite two contributes to different muscles, skeletal elements, and connective tissues of the head and cranial trunk region. Cells from somites two and three migrate latero-ventrally and contribute to the hypobranchial muscles mm. geniohyoideus and rectus cervicis. We provide evidence that the specific formation of the hypobranchial musculature from ventral processes of the somites might be variable in different classes of vertebrates. We further demonstrate that mm. cucullaris and dilatator laryngis, which were earlier thought to have a branchial origin, arise from somitic material in a manner very similar to the findings in quail-chick chimeras. Our findings indicate that the pattern of somitic derivatives is highly conserved within tetrapods.

  5. Positive in vitro wound healing effects of functional inclusion bodies of a lipoxygenase from the Mexican axolotl.

    Science.gov (United States)

    Stamm, Anne; Strauß, Sarah; Vogt, Peter; Scheper, Thomas; Pepelanova, Iliyana

    2018-04-07

    AmbLOXe is a lipoxygenase, which is up-regulated during limb-redevelopment in the Mexican axolotl, Ambystoma mexicanum, an animal with remarkable regeneration capacity. Previous studies have shown that mammalian cells transformed with the gene of this epidermal lipoxygenase display faster migration and wound closure rate during in vitro wound healing experiments. In this study, the gene of AmbLOXe was codon-optimized for expression in Escherichia coli and was produced in the insoluble fraction as protein aggregates. These inclusion bodies or nanopills were shown to be reservoirs containing functional protein during in vitro wound healing assays. For this purpose, functional inclusion bodies were used to coat cell culture surfaces prior cell seeding or were added directly to the medium after cells reached confluence. In both scenarios, AmbLOXe inclusion bodies led to faster migration rate and wound closure, in comparison to controls containing either no AmbLOXe or GFP inclusion bodies. Our results demonstrate that AmbLOXe inclusion bodies are functional and may serve as stable reservoirs of this enzyme. Nevertheless, further studies with soluble enzyme are also necessary in order to start elucidating the exact molecular substrates of AmbLOXe and the biochemical pathways involved in the wound healing effect.

  6. Dual embryonic origin of the hyobranchial apparatus in the Mexican axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Davidian, Asya; Malashichev, Yegor

    2013-01-01

    Traditionally, the cartilaginous viscerocranium of vertebrates is considered as neural crest (NC)-derived. Morphological work carried out on amphibian embryos in the first half of the XX century suggested potentially mesodermal origin for some hyobranchial elements. Since then, the embryonic sources of the hyobranchial apparatus in amphibians has not been investigated due to lack of an appropriate long-term labelling system. We performed homotopic transplantations of neural folds along with the majority of cells of the presumptive NC, and/or fragments of the head lateral plate mesoderm (LPM) from transgenic GFP+ into white embryos. In these experiments, the NC-derived GFP+ cells contributed to all hyobranchial elements, except for basibranchial 2, whereas the grafting of GFP+ head mesoderm led to a reverse labelling result. The grafting of only the most ventral part of the head LPM resulted in marking of the basibranchial 2 and the heart myocardium, implying their origin from a common mesodermal region. This is the first evidence of contribution of LPM of the head to cranial elements in any vertebrate. If compared to fish, birds, and mammals, in which all branchial skeletal elements are NC-derived, the axolotl (probably this is true for all amphibians) demonstrates an evolutionary deviation, in which the head LPM replaces NC cells in a hyobranchial element. This implies that cells of different embryonic origin may have the same developmental program, leading to the formation of identical (homologous) elements of the skeleton.

  7. MRI tracking of SPIO labelled stem cells in a true regenerative environment, the regenerating limb of the axolotl

    DEFF Research Database (Denmark)

    Lauridsen, Henrik; Foldager, Casper Bindzus; Hagensen, Mette

    are generally restricted by their limited regenerative potential. Conversely, excellent animal models for regenerative studies exist in lower vertebrates such as the urodele amphibians (salamanders and newts), exemplified in the iconic Mexican axolotl (Ambystoma mexicanum) capable of regenerating whole limbs...

  8. Evolutionary genetics of metamorphic failure using wild-caught vs. laboratory axolotls (Ambystoma mexicanum).

    Science.gov (United States)

    Voss, S R; Shaffer, H B

    2000-09-01

    In many organisms metamorphosis allows for an ecologically important habitat-shift from water to land. However, in some salamanders an adaptive life cycle mode has evolved that is characterized by metamorphic failure (paedomorphosis); these species remain in the aquatic habitat throughout the life cycle. Perhaps the most famous example of metamorphic failure is the Mexican axolotl (Ambystoma mexicanum), which has become a focal species for developmental biology since it was introduced into laboratory culture in the 1800s. Our previous genetic linkage mapping analysis, using an interspecific crossing design, demonstrated that a major gene effect underlies the expression of metamorphic failure in laboratory stocks of the Mexican axolotl. Here, we repeated this experiment using A. mexicanum that were sampled directly from their natural habitat at Lake Xochimilco, Mexico. We found no significant association between the major gene and metamorphic failure when wild-caught axolotls were used in the experimental design, although there is evidence of a smaller genetic effect. Thus, there appears to be genetic variation among Mexican axolotls (and possibly A. tigrinum tigrinum) at loci that contribute to metamorphic failure. This result suggests a role for more than one mutation and possibly artificial selection in the evolution of the major gene effect in the laboratory Mexican axolotl.

  9. Propofol (2,6-diisopropylphenol) is an applicable immersion anesthetic in the axolotl with potential uses in hemodynamic and neurophysiological experiments

    DEFF Research Database (Denmark)

    Thygesen, Mathias; Rasmussen, Mikkel Mylius; Madsen, Jesper Guldsmed

    2017-01-01

    The Mexican axolotl (Ambystoma mexicanum) is an important model species in regenerative biology. Traditionally, axolotls are anesthetized using benzocaine or MS-222, both of which act to inhibit voltage gated sodium channels thereby preventing action potential propagation. In some neurophysiologi......The Mexican axolotl (Ambystoma mexicanum) is an important model species in regenerative biology. Traditionally, axolotls are anesthetized using benzocaine or MS-222, both of which act to inhibit voltage gated sodium channels thereby preventing action potential propagation. In some...... neurophysiological experiments this is not desirable; therefore we tested propofol as an alternative anesthetic in the axolotl. We evaluated benzocaine, MS-222, and propofol's cardiovascular effects, effects on action potential propagation in the spinal cord, and gross limb regenerative effects. We found...

  10. Hyperbaric oxygen therapy in a true regenerative environment, the regenerating limb of the axolotl

    DEFF Research Database (Denmark)

    Hansen, Kasper; Lauridsen, Henrik; Pedersen, Michael

    2012-01-01

    vertebrates such as the urodele amphibians (salamanders and newts), are excellent animal models for regenerative studies. The iconic Mexican axolotl (Ambystoma mexicanum) is capable of regenerating whole limbs, tail, jaw, and many inner organs, by dedifferentiation of cells to form a blastema (collection...

  11. Optimized axolotl (Ambystoma mexicanum) husbandry, breeding, metamorphosis, transgenesis and tamoxifen-mediated recombination.

    Science.gov (United States)

    Khattak, Shahryar; Murawala, Prayag; Andreas, Heino; Kappert, Verena; Schuez, Maritta; Sandoval-Guzmán, Tatiana; Crawford, Karen; Tanaka, Elly M

    2014-03-01

    The axolotl (Mexican salamander, Ambystoma mexicanum) has become a very useful model organism for studying limb and spinal cord regeneration because of its high regenerative capacity. Here we present a protocol for successfully mating and breeding axolotls in the laboratory throughout the year, for metamorphosing axolotls by a single i.p. injection and for axolotl transgenesis using I-SceI meganuclease and the mini Tol2 transposon system. Tol2-mediated transgenesis provides different features and advantages compared with I-SceI-mediated transgenesis, and it can result in more than 30% of animals expressing the transgene throughout their bodies so that they can be directly used for experimentation. By using Tol2-mediated transgenesis, experiments can be performed within weeks (e.g., 5-6 weeks for obtaining 2-3-cm-long larvae) without the need to establish germline transgenic lines (which take 12-18 months). In addition, we describe here tamoxifen-induced Cre-mediated recombination in transgenic axolotls.

  12. Identification of Mutant Genes and Introgressed Tiger Salamander DNA in the Laboratory Axolotl, Ambystoma mexicanum.

    Science.gov (United States)

    Woodcock, M Ryan; Vaughn-Wolfe, Jennifer; Elias, Alexandra; Kump, D Kevin; Kendall, Katharina Denise; Timoshevskaya, Nataliya; Timoshevskiy, Vladimir; Perry, Dustin W; Smith, Jeramiah J; Spiewak, Jessica E; Parichy, David M; Voss, S Randal

    2017-01-31

    The molecular genetic toolkit of the Mexican axolotl, a classic model organism, has matured to the point where it is now possible to identify genes for mutant phenotypes. We used a positional cloning-candidate gene approach to identify molecular bases for two historic axolotl pigment phenotypes: white and albino. White (d/d) mutants have defects in pigment cell morphogenesis and differentiation, whereas albino (a/a) mutants lack melanin. We identified in white mutants a transcriptional defect in endothelin 3 (edn3), encoding a peptide factor that promotes pigment cell migration and differentiation in other vertebrates. Transgenic restoration of Edn3 expression rescued the homozygous white mutant phenotype. We mapped the albino locus to tyrosinase (tyr) and identified polymorphisms shared between the albino allele (tyr a ) and tyr alleles in a Minnesota population of tiger salamanders from which the albino trait was introgressed. tyr a has a 142 bp deletion and similar engineered alleles recapitulated the albino phenotype. Finally, we show that historical introgression of tyr a significantly altered genomic composition of the laboratory axolotl, yielding a distinct, hybrid strain of ambystomatid salamander. Our results demonstrate the feasibility of identifying genes for traits in the laboratory Mexican axolotl.

  13. Propofol (2,6-diisopropylphenol) is an applicable immersion anesthetic in the axolotl with potential uses in hemodynamic and neurophysiological experiments

    DEFF Research Database (Denmark)

    Thygesen, Mathias; Rasmussen, Mikkel Mylius; Madsen, Jesper Guldsmed

    2017-01-01

    The Mexican axolotl (Ambystoma mexicanum) is an important model species in regenerative biology. Traditionally, axolotls are anesthetized using benzocaine or MS-222, both of which act to inhibit voltage gated sodium channels thereby preventing action potential propagation. In some...... neurophysiological experiments this is not desirable; therefore we tested propofol as an alternative anesthetic in the axolotl. We evaluated benzocaine, MS-222, and propofol's cardiovascular effects, effects on action potential propagation in the spinal cord, and gross limb regenerative effects. We found...... that propofol is applicable as a general anesthetic in the axolotl allowing for neurophysiological experiments and yielding a stable anesthesia with significantly less cardiovascular effect than both benzocaine and MS-222. Additionally, propofol did not affect gross limb regeneration. In conclusion we suggest...

  14. Generation of axolotl hematopoietic chimeras

    Directory of Open Access Journals (Sweden)

    David Lopez

    2015-02-01

    Full Text Available Wound repair is an extremely complex process that requires precise coordination between various cell types including immune cells.  Unfortunately, in mammals this usually results in scar formation instead of restoration of the original fully functional tissue, otherwise known as regeneration.  Various animal models like frogs and salamanders are currently being studied to determine the intracellular and intercellular pathways, controlled by gene expression, that elicit cell proliferation, differentiation, and migration of cells during regenerative healing.  Now, the necessary genetic tools to map regenerative pathways are becoming available for the axolotl salamander, thus allowing comparative studies between scarring and regeneration.  Here, we describe in detail three methods to produce axolotl hematopoietic cell-tagged chimeras for the study of hematopoiesis and regeneration.

  15. Transgenesis in axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Khattak, Shahryar; Tanaka, Elly M

    2015-01-01

    Transgenic animals have been indispensable in elucidating and deciphering mechanisms underlying various biological phenomena. In regeneration, transgenic animals expressing fluorescent protein genes have been crucial for identifying the source cells for regeneration and the mechanism of blastema formation. Animals are usually generated by manipulating their genome using various techniques at/in one cell embryo/fertilized egg stage. Here, we describe the generation of germline transgenic axolotls (Ambystoma mexicanum) using the I-SceI meganuclease and Tol2 transposase.

  16. Gallium nitrate: effects on cartilage during limb regeneration in the axolotl, Ambystoma mexicanum.

    Science.gov (United States)

    Tassava, Roy A; Mendenhall, Luciara; Apseloff, Glen; Gerber, Nicholas

    2002-09-01

    Gallium nitrate, a drug shown to have efficacy in Paget's disease of bone, hypercalcemia of malignancy, and a variety of experimental autoimmune diseases, also inhibits the growth of some types of cancer. We examined dose and timing of administration of gallium nitrate on limb regeneration in the Mexican axolotl, Ambystoma mexicanum. Administered by intraperitoneal injection, gallium nitrate inhibited limb regeneration in a dose-dependent manner. Gallium nitrate initially suppressed epithelial wound healing and subsequently distorted both anterior-posterior and proximo-distal chondrogenic patterns. Gallium nitrate given at three days after amputation severely inhibited regeneration at high doses (6.25 mg/axolotl) and altered the normal patterning of the regenerates at low doses (3.75 mg/axolotl). Administration of 6.25 mg of gallium nitrate at four or 14 days prior to amputation also inhibited regeneration. In amputated limbs of gallium-treated axolotls, the chondrocytes were lost from inside the radius/ulna. Limbs that regenerated after gallium treatment was terminated showed blastema formation preferentially over the ulna. New cartilage of the regenerate often attached to the sides of the existing radius/ulna proximally into the stump and less so to the distal cut ends. J. Exp. Zool. 293:384-394, 2002. Copyright 2002 Wiley-Liss, Inc.

  17. Regeneration of limb joints in the axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Lee, Jangwoo; Gardiner, David M

    2012-01-01

    In spite of numerous investigations of regenerating salamander limbs, little attention has been paid to the details of how joints are reformed. An understanding of the process and mechanisms of joint regeneration in this model system for tetrapod limb regeneration would provide insights into developing novel therapies for inducing joint regeneration in humans. To this end, we have used the axolotl (Mexican Salamander) model of limb regeneration to describe the morphology and the expression patterns of marker genes during joint regeneration in response to limb amputation. These data are consistent with the hypothesis that the mechanisms of joint formation whether it be development or regeneration are conserved. We also have determined that defects in the epiphyseal region of both forelimbs and hind limbs in the axolotl are regenerated only when the defect is small. As is the case with defects in the diaphysis, there is a critical size above which the endogenous regenerative response is not sufficient to regenerate the joint. This non-regenerative response in an animal that has the ability to regenerate perfectly provides the opportunity to screen for the signaling pathways to induce regeneration of articular cartilage and joints.

  18. Regeneration of limb joints in the axolotl (Ambystoma mexicanum.

    Directory of Open Access Journals (Sweden)

    Jangwoo Lee

    Full Text Available In spite of numerous investigations of regenerating salamander limbs, little attention has been paid to the details of how joints are reformed. An understanding of the process and mechanisms of joint regeneration in this model system for tetrapod limb regeneration would provide insights into developing novel therapies for inducing joint regeneration in humans. To this end, we have used the axolotl (Mexican Salamander model of limb regeneration to describe the morphology and the expression patterns of marker genes during joint regeneration in response to limb amputation. These data are consistent with the hypothesis that the mechanisms of joint formation whether it be development or regeneration are conserved. We also have determined that defects in the epiphyseal region of both forelimbs and hind limbs in the axolotl are regenerated only when the defect is small. As is the case with defects in the diaphysis, there is a critical size above which the endogenous regenerative response is not sufficient to regenerate the joint. This non-regenerative response in an animal that has the ability to regenerate perfectly provides the opportunity to screen for the signaling pathways to induce regeneration of articular cartilage and joints.

  19. Pathological features of olfactory neuroblastoma in an axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Shioda, Chieko; Uchida, Kazuyuki; Nakayama, Hiroyuki

    2011-08-01

    A one-year-old, female Mexican axolotl (Ambystoma mexicanum) had a rough-surfaced, polypoid, pink tumor mass of approximately 10 mm in diameter in the oral cavity. Histologically, the tumor extended from the ethmoturbinate region and into the oral cavity and had replaced some of the maxillary bone tissue. The tumor mass was composed of a lobular architecture of small round-shaped tumor cells with occasional Flexner-Wintersteiner-like rosette formation. There were no metastatic lesions in the other organs. Immunohistochemically, the tumor cells were partly positive for several neural markers (class III beta-tubulin, S-100 protein, and doublecortin) and intensely positive for an epithelial marker (cytokeratin AE1/AE3). These results suggest that the present tumor originated from neuroectodermal tissue. Considering the location and histological and immunohistochemical features of the tumor, a diagnosis of olfactory neuroblastoma was made.

  20. Particles and Fields: Seventh Mexican Workshop, AIP Conference Proceedings, No. 531 [APCPCS

    International Nuclear Information System (INIS)

    Ayala, A.; Contreras, G.; Herrera, G.

    2000-01-01

    The workshop provides courses and lectures in which students have the opportunity to learn about new trends in the field. There was a special session dedicated to Leon M. Lederman, who was awarded a medal by the Division of Particles and Fields of the Mexican Physical Society in recognition of his support in the creation of experimental high energy physics groups in Latin America. There are also parallel sessions of short seminars in which participants present their research work

  1. Myofibril-Inducing RNA (MIR is essential for tropomyosin expression and myofibrillogenesis in axolotl hearts

    Directory of Open Access Journals (Sweden)

    Lemanski Sharon L

    2009-09-01

    Full Text Available Abstract The Mexican axolotl, Ambystoma mexicanum, carries the naturally-occurring recessive mutant gene 'c' that results in a failure of homozygous (c/c embryos to form hearts that beat because of an absence of organized myofibrils. Our previous studies have shown that a noncoding RNA, Myofibril-Inducing RNA (MIR, is capable of promoting myofibrillogenesis and heart beating in the mutant (c/c axolotls. The present study demonstrates that the MIR gene is essential for tropomyosin (TM expression in axolotl hearts during development. Gene expression studies show that mRNA expression of various tropomyosin isoforms in untreated mutant hearts and in normal hearts knocked down with double-stranded MIR (dsMIR are similar to untreated normal. However, at the protein level, selected tropomyosin isoforms are significantly reduced in mutant and dsMIR treated normal hearts. These results suggest that MIR is involved in controlling the translation or post-translation of various TM isoforms and subsequently of regulating cardiac contractility.

  2. Neuregulin-1 signaling is essential for nerve-dependent axolotl limb regeneration.

    Science.gov (United States)

    Farkas, Johanna E; Freitas, Polina D; Bryant, Donald M; Whited, Jessica L; Monaghan, James R

    2016-08-01

    The Mexican axolotl (Ambystoma mexicanum) is capable of fully regenerating amputated limbs, but denervation of the limb inhibits the formation of the post-injury proliferative mass called the blastema. The molecular basis behind this phenomenon remains poorly understood, but previous studies have suggested that nerves support regeneration via the secretion of essential growth-promoting factors. An essential nerve-derived factor must be found in the blastema, capable of rescuing regeneration in denervated limbs, and its inhibition must prevent regeneration. Here, we show that the neuronally secreted protein Neuregulin-1 (NRG1) fulfills all these criteria in the axolotl. Immunohistochemistry and in situ hybridization of NRG1 and its active receptor ErbB2 revealed that they are expressed in regenerating blastemas but lost upon denervation. NRG1 was localized to the wound epithelium prior to blastema formation and was later strongly expressed in proliferating blastemal cells. Supplementation by implantation of NRG1-soaked beads rescued regeneration to digits in denervated limbs, and pharmacological inhibition of NRG1 signaling reduced cell proliferation, blocked blastema formation and induced aberrant collagen deposition in fully innervated limbs. Taken together, our results show that nerve-dependent NRG1/ErbB2 signaling promotes blastemal proliferation in the regenerating limb and may play an essential role in blastema formation, thus providing insight into the longstanding question of why nerves are required for axolotl limb regeneration. © 2016. Published by The Company of Biologists Ltd.

  3. Proceedings of the 4. National Congress of the Mexican Society of Radiological Safety C.A

    International Nuclear Information System (INIS)

    1991-01-01

    In these sessions it had the participation of personalities of diverse internationally grateful organizations, with exhibitions about the situation of the nuclear industry of power, the applications of the radiations and the radiological safety in the international context. Also its were presented works about Emergency plans in Nuclear facilities and plants, Nuclear medicine, Food processing, Thermal neutrons, Neutron dosimetry, Charged particles, Thermoluminescence, Industrial radiography, Radiation monitoring, all of them with the participation of specialists with international prestige. The 41 works that are presented in the technical sessions come from Spanish, Brazilian, Greek and Mexican grateful institutions. All they are a sample of the intense activity in investigation and development in the areas of the nuclear industry as of the radiological safety. This congress reveals the impulse that the nuclear community grants to the formation of human resources

  4. Thyroxine-induced metamorphosis in the axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Coots, Peggy S; Seifert, Ashley W

    2015-01-01

    The axolotl (Ambystoma mexicanum) has remained an important model for regeneration and developmental biology for over a century. Although axolotls in captive-bred colonies usually exist in an aquatic form, they retain the ability to undergo metamorphosis following exposure to thyroid hormone. Here we present a robust method for inducing metamorphosis in adult axolotls that results in high survivability and produces terrestrial animals that can be maintained in long-term captivity.

  5. Limb Regeneration in Axolotl: Is It Superhealing?

    Directory of Open Access Journals (Sweden)

    Stéphane Roy

    2006-01-01

    Full Text Available The ability of axolotls to regenerate their limbs is almost legendary. In fact, urodeles such as the axolotl are the only vertebrates that can regenerate multiple structures like their limbs, jaws, tail, spinal cord, and skin (the list goes on throughout their lives. It is therefore surprising to realize, although we have known of their regenerative potential for over 200 years, how little we understand the mechanisms behind this achievement of adult tissue morphogenesis. Many observations can be drawn between regeneration and other disciplines such as development and wound healing. In this review, we present new developments in functional analysis that will help to address the role of specific genes during the process of regeneration. We also present an analysis of the resemblance between wound healing and regeneration, and discuss whether axolotls are superhealers. A better understanding of these animals' regenerative capacity could lead to major benefits by providing regenerative medicine with directions on how to develop therapeutic approaches leading to regeneration in humans.

  6. Transcriptional landscapes of Axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Caballero-Pérez, Juan; Espinal-Centeno, Annie; Falcon, Francisco; García-Ortega, Luis F; Curiel-Quesada, Everardo; Cruz-Hernández, Andrés; Bako, Laszlo; Chen, Xuemei; Martínez, Octavio; Alberto Arteaga-Vázquez, Mario; Herrera-Estrella, Luis; Cruz-Ramírez, Alfredo

    2018-01-15

    The axolotl (Ambystoma mexicanum) is the vertebrate model system with the highest regeneration capacity. Experimental tools established over the past 100 years have been fundamental to start unraveling the cellular and molecular basis of tissue and limb regeneration. In the absence of a reference genome for the Axolotl, transcriptomic analysis become fundamental to understand the genetic basis of regeneration. Here we present one of the most diverse transcriptomic data sets for Axolotl by profiling coding and non-coding RNAs from diverse tissues. We reconstructed a population of 115,906 putative protein coding mRNAs as full ORFs (including isoforms). We also identified 352 conserved miRNAs and 297 novel putative mature miRNAs. Systematic enrichment analysis of gene expression allowed us to identify tissue-specific protein-coding transcripts. We also found putative novel and conserved microRNAs which potentially target mRNAs which are reported as important disease candidates in heart and liver. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Lens regeneration in axolotl: new evidence of developmental plasticity

    Directory of Open Access Journals (Sweden)

    Suetsugu-Maki Rinako

    2012-12-01

    Full Text Available Abstract Background Among vertebrates lens regeneration is most pronounced in newts, which have the ability to regenerate the entire lens throughout their lives. Regeneration occurs from the dorsal iris by transdifferentiation of the pigment epithelial cells. Interestingly, the ventral iris never contributes to regeneration. Frogs have limited lens regeneration capacity elicited from the cornea during pre-metamorphic stages. The axolotl is another salamander which, like the newt, regenerates its limbs or its tail with the spinal cord, but up until now all reports have shown that it does not regenerate the lens. Results Here we present a detailed analysis during different stages of axolotl development, and we show that despite previous beliefs the axolotl does regenerate the lens, however, only during a limited time after hatching. We have found that starting at stage 44 (forelimb bud stage lens regeneration is possible for nearly two weeks. Regeneration occurs from the iris but, in contrast to the newt, regeneration can be elicited from either the dorsal or the ventral iris and, occasionally, even from both in the same eye. Similar studies in the zebra fish concluded that lens regeneration is not possible. Conclusions Regeneration of the lens is possible in the axolotl, but differs from both frogs and newts. Thus the axolotl iris provides a novel and more plastic strategy for lens regeneration.

  8. Novel axolotl cardiac function analysis method using magnetic resonance imaging.

    Directory of Open Access Journals (Sweden)

    Pedro Gomes Sanches

    Full Text Available The salamander axolotl is capable of complete regeneration of amputated heart tissue. However, non-invasive imaging tools for assessing its cardiac function were so far not employed. In this study, cardiac magnetic resonance imaging is introduced as a non-invasive technique to image heart function of axolotls. Three axolotls were imaged with magnetic resonance imaging using a retrospectively gated Fast Low Angle Shot cine sequence. Within one scanning session the axolotl heart was imaged three times in all planes, consecutively. Heart rate, ejection fraction, stroke volume and cardiac output were calculated using three techniques: (1 combined long-axis, (2 short-axis series, and (3 ultrasound (control for heart rate only. All values are presented as mean ± standard deviation. Heart rate (beats per minute among different animals was 32.2±6.0 (long axis, 30.4±5.5 (short axis and 32.7±4.9 (ultrasound and statistically similar regardless of the imaging method (p > 0.05. Ejection fraction (% was 59.6±10.8 (long axis and 48.1±11.3 (short axis and it differed significantly (p = 0.019. Stroke volume (μl/beat was 133.7±33.7 (long axis and 93.2±31.2 (short axis, also differed significantly (p = 0.015. Calculations were consistent among the animals and over three repeated measurements. The heart rate varied depending on depth of anaesthesia. We described a new method for defining and imaging the anatomical planes of the axolotl heart and propose one of our techniques (long axis analysis may prove useful in defining cardiac function in regenerating axolotl hearts.

  9. Proceedings of the 7th National Congress of the Mexican Society of Radiological Safety C.A

    International Nuclear Information System (INIS)

    1997-01-01

    The Mexican Society of Radiological Safety, celebrates on this time the 100 Anniversary of the radioactivity discovery, phenomenon coined by Marie Curie in 1898 and discover by Henry Beckerel in March 1896, when both were working with natural radioactive isotopes. Subsequently, on the new age of Physics, the use of radioactive isotopes was impulse by the invention of Cyclotron made by Dr. Ernest Orland Lawrence in the United States, which permits the manufacturing of tens of artificial radioactive isotopes which convert its in an indispensable tool in Medicine, Industry, Research, Agriculture and other disciplines, by its wide variety of applications, creating the radiological safety culture by the implicit risk in the use of these materials. From its creation in 1976, our society was removing to promote the radiological safety and two years each celebrates its National Congress removing specialists in this discipline and invite new generations to awake their interest by this useful field. (Author)

  10. Low submetamorphic doses of dexamethasone and thyroxine induce complete metamorphosis in the axolotl (Ambystoma mexicanum) when injected together.

    Science.gov (United States)

    Kühn, Eduard R; De Groef, Bert; Grommen, Sylvia V H; Van der Geyten, Serge; Darras, Veerle M

    2004-06-01

    Entanglement of functions between the adrenal (or interrenal) and thyroid axis has been well described for all vertebrates and can be tracked down up to the level of gene expression. Both thyroid hormones and corticosteroids may induce morphological changes leading to metamorphosis climax in the neotenic Mexican axolotl (Ambystoma mexicanum). In a first series of experiments, metamorphosis was induced with an injection of 25 microg T(4) on three alternate days as judged by a decrease in body weight and tail height together with complete gill resorption. This injection also resulted in elevated plasma concentrations of T(3) and corticosterone. Previous results have indicated that the same dose of dexamethasone (DEX) is ineffective in this regard (Gen. Comp. Endocrinol. 127 (2002) 157). In a second series of experiments low doses of T(4) (0.5 microg) or DEX (5 microg) were ineffective to induce morphological changes. However, when these submetamorphic doses were injected together, morphological changes were observed within one week leading to complete metamorphosis. It is concluded that thyroid hormones combined with corticosteroids are essential for metamorphosis in the axolotl and that only high doses of either thyroid hormone or corticosteroid can induce morphological changes when injected separately.

  11. Proceedings

    International Nuclear Information System (INIS)

    1974-01-01

    These 1974 Proceedings of the European Society of Nuclear Methods in Agriculture contain reports in the form of minutes of the meetings of various working groups of the Society, the programme and official addresses of the fifth annual meeting including annual reports of the chairman and the secretary of the Society, and the reports of each of the eleven working groups as well as the four following surveys entitled: 1) some aspects of research in plant breeding, conservation of genetic resources in connection with irradiation processes (by A. Jacques from FAO), 2) our responsibility for the environment (by D. Zeeuw from ITAL), 3) pilot plant for the irradiation of sewage sludge (by A. Suesz from Bayerische Landesanstalt fuer Bodenkultur und Pflanzenbau, Munich), 4) nuclear agronomy in France (by P. Guerin de Montgareuil from CEN, Cadarache). Summaries and provisional papers on presented topics will be published in ''ESNA Newsletter''

  12. Proceedings:

    Energy Technology Data Exchange (ETDEWEB)

    Sidhu, S.S. (comp.)

    1987-12-01

    With increasingly stringent requirements on the performance of accelerators and storage rings, there is a wide interest in modeling-based control. The organizers recognized the need to have an overview and discussion on the current status of modeling-based accelerator control and how advances in computer technology, software engineering, and expert systems can impact control and diagnosis. As a result, a workshop was organized at the Brookhaven National Laboratory on August 17-18, 1987. It was made possible by the joint support of the AGS, NSLS and Applied Mathematics Departments of BNL. The talks and discussions were divided into three main topics: elements of modeling, knowledge representation, and integration of modeling-based control systems with AI and workstations. This volume is the unedited collection of papers, presented at the Workshop. Separate abstracts were prepared for 10 papers in these proceedings.

  13. Early regulation of axolotl limb regeneration.

    Science.gov (United States)

    Makanae, Aki; Satoh, Akira

    2012-10-01

    Amphibian limb regeneration has been studied for a long time. In amphibian limb regeneration, an undifferentiated blastema is formed around the region damaged by amputation. The induction process of blastema formation has remained largely unknown because it is difficult to study the induction of limb regeneration. The recently developed accessory limb model (ALM) allows the investigation of limb induction and reveals early events of amphibian limb regeneration. The interaction between nerves and wound epidermis/epithelium is an important aspect of limb regeneration. During early limb regeneration, neurotrophic factors act on wound epithelium, leading to development of a functional epidermis/epithelium called the apical epithelial cap (AEC). AEC and nerves create a specific environment that inhibits wound healing and induces regeneration through blastema formation. It is suggested that FGF-signaling and MMP activities participate in creating a regenerative environment. To understand why urodele amphibians can create such a regenerative environment and humans cannot, it is necessary to identify the similarities and differences between regenerative and nonregenerative animals. Here we focus on ALM to consider limb regeneration from a new perspective and we also reported that focal adhesion kinase (FAK)-Src signaling controlled fibroblasts migration in axolotl limb regeneration. Copyright © 2012 Wiley Periodicals, Inc.

  14. Continuous growth of the motor system in the axolotl

    International Nuclear Information System (INIS)

    Holder, N.; Clarke, J.D.; Stephens, N.; Wilson, S.W.; Orsi, C.; Bloomer, T.; Tonge, D.A.

    1991-01-01

    During growth of the axolotl, motor neurons, and muscle fibres are added to the motor system. By double labelling neurons with tritiated thymidine and retrogradely transported HRP, we show that some motor neurons are born at postembryonic stages. Further analysis of motor neurons with the aid of HRP reveals this population of newly born cells relatively frequently in small (5-7 cm long) axolotls, but only rarely in large (7-13 cm long) axolotls. Evidence is presented that suggests that these immature cells are in the process of migrating from close to the ependyma out to the ventral horn. HRP transport also reveals growth cones of advancing axons within spinal nerves in animals up to 6 cm in length. Cell counts by light and electron microscopic methods show that muscle fibres are generated throughout larval life in the iliotibialis, a typical limb muscle. This analysis provides data consistent with the notion that new muscle fibres are added from a localised growth zone situated at the superficial edge of the muscle. These results are discussed in terms of the correlation between continuous growth of the motor system and the ability of the axolotl to functionally repair lesions to the peripheral nervous system

  15. Novel axolotl cardiac function analysis method using magnetic resonance imaging

    NARCIS (Netherlands)

    Sanches, Pedro Gomes; Op 't Veld, Roel C.; de Graaf, Wolter; Strijkers, Gustav J.; Grüll, Holger

    2017-01-01

    The salamander axolotl is capable of complete regeneration of amputated heart tissue. However, non-invasive imaging tools for assessing its cardiac function were so far not employed. In this study, cardiac magnetic resonance imaging is introduced as a non-invasive technique to image heart function

  16. Novel axolotl cardiac function analysis method using magnetic resonance imaging

    NARCIS (Netherlands)

    Sanches, P.G.; Op ‘t Veld, R.C.; de Graaf, W.; Strijkers, G.J.; Grüll, H.

    2017-01-01

    The salamander axolotl is capable of complete regeneration of amputated heart tissue. However, non-invasive imaging tools for assessing its cardiac function were so far not employed. In this study, cardiac magnetic resonance imaging is introduced as a noninvasive technique to image heart function of

  17. Proceedings of the Annual Conference on Child Abuse and Neglect in the Mexican American Community (1st, Laredo, Texas, May 26-29, 1981).

    Science.gov (United States)

    Gibson, Guadalupe, Ed.,; Torres, Angelina Moreno

    The conference focused attention on the severe problems of abuse and neglect among Mexican American children, particularly among migrant children. The welcome address discussed the plight and hardship endured by the Mexican American migrant worker and family. The keynote address emphasized the fact that minority families, who are usually poor, and…

  18. ISOLATION AND CHARACTERIZATION OF AXOLOTL NPDC-1 AND ITS EFFECTS ON RETINOIC ACID RECEPTOR SIGNALING

    Science.gov (United States)

    Theodosiou, Maria; Monaghan, James R; Spencer, Michael L; Voss, S Randal; Noonan, Daniel J

    2009-01-01

    Retinoic acid, a key morphogen in early vertebrate development and tissue regeneration, mediates its effects through the binding of receptors that act as ligand-induced transcription factors. These binding events function to recruit an array of transcription co-regulatory proteins to specific gene promoters. One such co-regulatory protein, neuronal proliferation and differentiation control-1 (NPDC-1), is broadly expressed during mammalian development and functions as an in vitro repressor of retinoic acid receptor (RAR)-mediated transcription. To obtain comparative and developmental insights about NPDC-1 function, we cloned the axolotl (Ambystoma mexicanum) orthologue and measured transcript abundances among tissues sampled during the embryonic and juvenile phases of development, and also during spinal cord regeneration. Structurally, the axolotl orthologue of NPDC-1 retained sequence identity to mammalian sequences in all functional domains. Functionally, we observed that axolotl NPDC-1 mRNA expression peaked late in embryogenesis, with highest levels of expression occurring during the time of limb development, a process regulated by retinoic acid signaling. Also similar to what has been observed in mammals, axolotl NPDC-1 directly interacts with axolotl RAR, modulates axolotl RAR DNA binding, and represses cell proliferation and axolotl RAR-mediated gene transcription. These data justify axolotl as a model to further investigate NPDC-1 and its role in regulating retinoic acid signaling. PMID:17331771

  19. Identification of reference genes and validation for gene expression studies in diverse axolotl (Ambystoma mexicanum) tissues.

    Science.gov (United States)

    Guelke, Eileen; Bucan, Vesna; Liebsch, Christina; Lazaridis, Andrea; Radtke, Christine; Vogt, Peter M; Reimers, Kerstin

    2015-04-10

    For the precise quantitative RT-PCR normalization a set of valid reference genes is obligatory. Moreover have to be taken into concern the experimental conditions as they bias the regulation of reference genes. Up till now, no reference targets have been described for the axolotl (Ambystoma mexicanum). In a search in the public database SalSite for genetic information of the axolotl we identified fourteen presumptive reference genes, eleven of which were further tested for their gene expression stability. This study characterizes the expressional patterns of 11 putative endogenous control genes during axolotl limb regeneration and in an axolotl tissue panel. All 11 reference genes showed variable expression. Strikingly, ACTB was to be found most stable expressed in all comparative tissue groups, so we reason it to be suitable for all different kinds of axolotl tissue-type investigations. Moreover do we suggest GAPDH and RPLP0 as suitable for certain axolotl tissue analysis. When it comes to axolotl limb regeneration, a validated pair of reference genes is ODC and RPLP0. With these findings, new insights into axolotl gene expression profiling might be gained. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Axolotl cells and tissues enhances cutaneous wound healing in mice

    OpenAIRE

    DEMIRCAN, Turan; KESKIN, Ilknur; GUNAL, Yalcin; ILHAN, Ayse Elif; KOLBASI, Bircan; OZTURK, Gurkan

    2017-01-01

    Adult mammalian skin wound repair is defective due to loss of the regulation in balancing the complete epithelial regeneration and excessive connective tissue production, and this repair process commonly results in scar tissue formation. However, unlike mammals, adult salamanders repair the wounds by regeneration compared to scarring. To elucidate the healing capability of a salamander, Axolotl, in a different species, here we addressed this question by treating the wounds in mice with Axolot...

  1. Diffusion tensor tractography reveals muscle reconnection during axolotl limb regeneration.

    Directory of Open Access Journals (Sweden)

    Cheng-Han Wu

    Full Text Available Axolotls have amazing ability to regenerate their lost limbs. Our previous works showed that after amputation the remnant muscle ends remained at their original location whilst sending satellite cells into the regenerating parts to develop into early muscle fibers in the late differentiation stage. The parental and the newly formed muscle fibers were not connected until very late stage. The present study used non-invasive diffusion tensor imaging (DTI to monitor weekly axolotl upper arm muscles after amputation of their upper arms. DTI tractography showed that the regenerating muscle fibers became visible at 9-wpa (weeks post amputation, but a gap was observed between the regenerating and parental muscles. The gap was filled at 10-wpa, indicating reconnection of the fibers of both muscles. This was confirmed by histology. The DTI results indicate that 23% of the muscle fibers were reconnected at 10-wpa. In conclusion, DTI can be used to visualize axolotls' skeletal muscles and the results of muscle reconnection were in accordance with our previous findings. This non-invasive technique will allow researchers to identify the timeframe in which muscle fiber reconnection takes place and thus enable the study of the mechanisms underlying this reconnection.

  2. Experimentally induced metamorphosis in axolotls reduces regenerative rate and fidelity

    Science.gov (United States)

    Stier, Adrian C.; Michonneau, François; Smith, Matthew D.; Pasch, Bret; Maden, Malcolm

    2014-01-01

    Abstract While most tetrapods are unable to regenerate severed body parts, amphibians display a remarkable ability to regenerate an array of structures. Frogs can regenerate appendages as larva, but they lose this ability around metamorphosis. In contrast, salamanders regenerate appendages as larva, juveniles, and adults. However, the extent to which fundamental traits (e.g., metamorphosis, body size, aging, etc.) restrict regenerative ability remains contentious. Here we utilize the ability of normally paedomorphic adult axolotls (Ambystoma mexicanum) to undergo induced metamorphosis by thyroxine exposure to test how metamorphosis and body size affects regeneration in age‐matched paedomorphic and metamorphic individuals. We show that body size does not affect regeneration in adult axolotls, but metamorphosis causes a twofold reduction in regeneration rate, and lead to carpal and digit malformations. Furthermore, we find evidence that metamorphic blastemal cells may take longer to traverse the cell cycle and display a lower proliferative rate. This study identifies the axolotl as a powerful system to study how metamorphosis restricts regeneration independently of developmental stage, body size, and age; and more broadly how metamorphosis affects tissue‐specific changes. PMID:27499857

  3. Comparative pelvic development of the axolotl (Ambystoma mexicanum) and the Australian lungfish (Neoceratodus forsteri): conservation and innovation across the fish-tetrapod transition.

    Science.gov (United States)

    Boisvert, Catherine Anne; Joss, Jean Mp; Ahlberg, Per E

    2013-01-23

    The fish-tetrapod transition was one of the major events in vertebrate evolution and was enabled by many morphological changes. Although the transformation of paired fish fins into tetrapod limbs has been a major topic of study in recent years, both from paleontological and comparative developmental perspectives, the interest has focused almost exclusively on the distal part of the appendage and in particular the origin of digits. Relatively little attention has been paid to the transformation of the pelvic girdle from a small unipartite structure to a large tripartite weight-bearing structure, allowing tetrapods to rely mostly on their hindlimbs for locomotion. In order to understand how the ischium and the ilium evolved and how the acetabulum was reoriented during this transition, growth series of the Australian lungfish Neoceratodus forsteri and the Mexican axolotl Ambystoma mexicanum were cleared and stained for cartilage and bone and immunostained for skeletal muscles. In order to understand the myological developmental data, hypotheses about the homologies of pelvic muscles in adults of Latimeria, Neoceratodus and Necturus were formulated based on descriptions from the literature of the coelacanth (Latimeria), the Australian Lungfish (Neoceratodus) and a salamander (Necturus). In the axolotl and the lungfish, the chondrification of the pelvic girdle starts at the acetabula and progresses anteriorly in the lungfish and anteriorly and posteriorly in the salamander. The ilium develops by extending dorsally to meet and connect to the sacral rib in the axolotl. Homologous muscles develop in the same order with the hypaxial musculature developing first, followed by the deep, then the superficial pelvic musculature. Development of the pelvic endoskeleton and musculature is very similar in Neoceratodus and Ambystoma. If the acetabulum is seen as being a fixed landmark, the evolution of the ischium only required pubic pre-chondrogenic cells to migrate posteriorly. It

  4. The axolotl (Ambystoma mexicanum), a neotenic amphibian, expresses functional thyroid hormone receptors.

    Science.gov (United States)

    Safi, Rachid; Bertrand, Stéphanie; Marchand, Oriane; Duffraisse, Marilyne; de Luze, Amaury; Vanacker, Jean-Marc; Maraninchi, Marie; Margotat, Alain; Demeneix, Barbara; Laudet, Vincent

    2004-02-01

    Neotenic amphibians such as the axolotl (Ambystoma mexicanum) are often unable to undergo metamorphosis under natural conditions. It is thought that neoteny represents a deviation from the standard course of amphibian ontogeny, affecting the thyroid axis at different levels from the central nervous system to peripheral organs. Thyroid hormone receptors (TRs) that bind the thyroid hormone (TH) T(3) have been described in axolotl. However, the full sequences of TR were needed to better characterize the TH response and to be able to assess their functional capacity at the molecular level. We report that each of the alpha and beta axolotl TRs bind both DNA and TH, and they activate transcription in response to TH in a mammalian cell-based transient transfection assay. Moreover, both TRs are expressed in axolotl tissues. Interestingly, each TR gene generates alternatively spliced isoforms, harboring partial or total deletions of the ligand-binding domain, which are expressed in vivo. Further, we found that in the axolotl, TH regulates the expression of stromelysin 3 and collagenase 3, which are TH target genes in Xenopus. Taken together, these results suggest that axolotl TRs are functional and that the molecular basis of neoteny in the axolotl is not linked to a major defect in TH response in peripheral tissues.

  5. Detailed tail proteomic analysis of axolotl (Ambystoma mexicanum) using an mRNA-seq reference database.

    Science.gov (United States)

    Demircan, Turan; Keskin, Ilknur; Dumlu, Seda Nilgün; Aytürk, Nilüfer; Avşaroğlu, Mahmut Erhan; Akgün, Emel; Öztürk, Gürkan; Baykal, Ahmet Tarık

    2017-01-01

    Salamander axolotl has been emerging as an important model for stem cell research due to its powerful regenerative capacity. Several advantages, such as the high capability of advanced tissue, organ, and appendages regeneration, promote axolotl as an ideal model system to extend our current understanding on the mechanisms of regeneration. Acknowledging the common molecular pathways between amphibians and mammals, there is a great potential to translate the messages from axolotl research to mammalian studies. However, the utilization of axolotl is hindered due to the lack of reference databases of genomic, transcriptomic, and proteomic data. Here, we introduce the proteome analysis of the axolotl tail section searched against an mRNA-seq database. We translated axolotl mRNA sequences to protein sequences and annotated these to process the LC-MS/MS data and identified 1001 nonredundant proteins. Functional classification of identified proteins was performed by gene ontology searches. The presence of some of the identified proteins was validated by in situ antibody labeling. Furthermore, we have analyzed the proteome expressional changes postamputation at three time points to evaluate the underlying mechanisms of the regeneration process. Taken together, this work expands the proteomics data of axolotl to contribute to its establishment as a fully utilized model. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Communicating with Mexican Americans: Por Su Buena Salud = Communicando Con Mexico Americanos: For Their Good Health. Proceedings of the Conference (Houston, TX, September 13-14, 1979).

    Science.gov (United States)

    Moore, Thomas J., Ed.; And Others

    The conference focused on the role of the Mexican American's cultural language, tradition, life style, health practices, and media utilization in the design of effective health education and information programs. Representing various local, state, and national health, education, and media organizations, the 108 participants attended sessions on…

  7. Injection of an antibody against a p21 c-Ha-ras protein inhibits cleavage in axolotl eggs.

    OpenAIRE

    Baltus, E; Hanocq-Quertier, J; Hanocq, F; Brachet, J

    1988-01-01

    The presence of a ras protein was demonstrated in cleaving axolotl eggs by selective immunoprecipitation with a polyclonal antibody against a peptide encoded by the c-Ha-ras oncogene, cellular homolog of the v-Ha-ras oncogene of Harvey rat sarcoma virus. Injection of this antibody into axolotl oocytes subjected to progesterone treatment does not prevent meiotic maturation. Injection of the same antibody into a blastomere of axolotl eggs at the 2- or 4-cell stage causes cleavage arrest in the ...

  8. A Tissue-Mapped Axolotl De Novo Transcriptome Enables Identification of Limb Regeneration Factors

    Directory of Open Access Journals (Sweden)

    Donald M. Bryant

    2017-01-01

    Full Text Available Mammals have extremely limited regenerative capabilities; however, axolotls are profoundly regenerative and can replace entire limbs. The mechanisms underlying limb regeneration remain poorly understood, partly because the enormous and incompletely sequenced genomes of axolotls have hindered the study of genes facilitating regeneration. We assembled and annotated a de novo transcriptome using RNA-sequencing profiles for a broad spectrum of tissues that is estimated to have near-complete sequence information for 88% of axolotl genes. We devised expression analyses that identified the axolotl orthologs of cirbp and kazald1 as highly expressed and enriched in blastemas. Using morpholino anti-sense oligonucleotides, we find evidence that cirbp plays a cytoprotective role during limb regeneration whereas manipulation of kazald1 expression disrupts regeneration. Our transcriptome and annotation resources greatly complement previous transcriptomic studies and will be a valuable resource for future research in regenerative biology.

  9. Misexpression experiment of Tbx5 in axolotl (Ambystoma mexicanum) hindlimb blastema.

    Science.gov (United States)

    Shimokawa, Takashi; Kominami, Rieko; Yasutaka, Satoru; Shinohara, Harumichi

    2013-01-01

    Axolotls (Ambystoma mexicanum) have the ability to regenerate amputated limbs throughout their life span. In the present study, we attempted to elucidate how axolotls can specify limb type correctly during the regeneration process. We misexpressed Tbx5 in regenerating hindlimb blastema, and consequently a forelimb-like hindlimb regenerated from the hindlimb blastema. On the other hand, no change was observed in Tbx5-overexpressing forelimb blastema, and thus we considered that Tbx5 plays a key role in the specification of forelimb during the regeneration process of axolotl limbs. However, axolotls' fore- and hindlimbs have very similar structures except for the number of fingers, and it was very difficult to judge whether the forelimb-like regenerate was a true forelimb or merely a forelimb-like hindlimb. Therefore, in order to confirm our conclusion, we have to investigate other genes that are expressed differentially between fore- and hindlimbs in future experiments.

  10. Data on chemical activation of Wnt/β-catenin during axolotl limb regeneration

    Directory of Open Access Journals (Sweden)

    Sabina Wischin

    2017-04-01

    Full Text Available Limb amputation in axolotls was performed to obtain data demonstrating that a chemical agonist of Wnt (int-related protein/β-catenin signalling can have a role in axolotl limb regeneration (Wischin et al., 2017 [1]. The data revealed that active β-catenin protein was present during limb regeneration in some Leydig cells in the epithelium; after the chemical treatment, it was observed in more Leydig cells. In addition, the chemical agonist of Wnt generated distinct limb malformation.

  11. Evidence for balancing selection at the DAB locus in the axolotl, Ambystoma mexicanum.

    Science.gov (United States)

    Richman, A D; Herrera, G; Reynoso, V H; Méndez, G; Zambrano, L

    2007-12-01

    The axolotl (Ambystoma mexicanum) has been characterized as immunodeficient, and the absence of major histocompatibility complex (MHC) class II polymorphism has been cited as a possible explanation. Here we present evidence for considerable allelic polymorphism at the MHC class II DAB locus for a sample of wild-caught axolotls. Evidence that these sequences are the product of balancing selection for disease resistance is discussed.

  12. Comparison of tissue processing methods for microvascular visualization in axolotls.

    Science.gov (United States)

    Montoro, Rodrigo; Dickie, Renee

    2017-01-01

    The vascular system, the pipeline for oxygen and nutrient delivery to tissues, is essential for vertebrate development, growth, injury repair, and regeneration. With their capacity to regenerate entire appendages throughout their lifespan, axolotls are an unparalleled model for vertebrate regeneration, but they lack many of the molecular tools that facilitate vascular imaging in other animal models. The determination of vascular metrics requires high quality image data for the discrimination of vessels from background tissue. Quantification of the vasculature using perfused, cleared specimens is well-established in mammalian systems, but has not been widely employed in amphibians. The objective of this study was to optimize tissue preparation methods for the visualization of the microvascular network in axolotls, providing a basis for the quantification of regenerative angiogenesis. To accomplish this aim, we performed intracardiac perfusion of pigment-based contrast agents and evaluated aqueous and non-aqueous clearing techniques. The methods were verified by comparing the quality of the vascular images and the observable vascular density across treatment groups. Simple and inexpensive, these tissue processing techniques will be of use in studies assessing vascular growth and remodeling within the context of regeneration. Advantages of this method include: •Higher contrast of the vasculature within the 3D context of the surrounding tissue •Enhanced detection of microvasculature facilitating vascular quantification •Compatibility with other labeling techniques.

  13. A histological atlas of the tissues and organs of neotenic and metamorphosed axolotl.

    Science.gov (United States)

    Demircan, Turan; İlhan, Ayşe Elif; Aytürk, Nilüfer; Yıldırım, Berna; Öztürk, Gürkan; Keskin, İlknur

    2016-09-01

    Axolotl (Ambystoma Mexicanum) has been emerging as a promising model in stem cell and regeneration researches due to its exceptional regenerative capacity. Although it represents lifelong lasting neoteny, induction to metamorphosis with thyroid hormones (THs) treatment advances the utilization of Axolotl in various studies. It has been reported that amphibians undergo anatomical and histological remodeling during metamorphosis and this transformation is crucial for adaptation to terrestrial conditions. However, there is no comprehensive histological investigation regarding the morphological alterations of Axolotl organs and tissues throughout the metamorphosis. Here, we reveal the histological differences or resemblances between the neotenic and metamorphic axolotl tissues. In order to examine structural features and cellular organization of Axolotl organs, we performed Hematoxylin & Eosin, Luxol-Fast blue, Masson's trichrome, Alcian blue, Orcein and Weigart's staining. Stained samples from brain, gallbladder, heart, intestine, liver, lung, muscle, skin, spleen, stomach, tail, tongue and vessel were analyzed under the light microscope. Our findings contribute to the validation of the link between newly acquired functions and structural changes of tissues and organs as observed in tail, skin, gallbladder and spleen. We believe that this descriptive work provides new insights for a better histological understanding of both neotenic and metamorphic Axolotl tissues. Copyright © 2016 Elsevier GmbH. All rights reserved.

  14. Network based transcription factor analysis of regenerating axolotl limbs

    Directory of Open Access Journals (Sweden)

    Cameron Jo Ann

    2011-03-01

    Full Text Available Abstract Background Studies on amphibian limb regeneration began in the early 1700's but we still do not completely understand the cellular and molecular events of this unique process. Understanding a complex biological process such as limb regeneration is more complicated than the knowledge of the individual genes or proteins involved. Here we followed a systems biology approach in an effort to construct the networks and pathways of protein interactions involved in formation of the accumulation blastema in regenerating axolotl limbs. Results We used the human orthologs of proteins previously identified by our research team as bait to identify the transcription factor (TF pathways and networks that regulate blastema formation in amputated axolotl limbs. The five most connected factors, c-Myc, SP1, HNF4A, ESR1 and p53 regulate ~50% of the proteins in our data. Among these, c-Myc and SP1 regulate 36.2% of the proteins. c-Myc was the most highly connected TF (71 targets. Network analysis showed that TGF-β1 and fibronectin (FN lead to the activation of these TFs. We found that other TFs known to be involved in epigenetic reprogramming, such as Klf4, Oct4, and Lin28 are also connected to c-Myc and SP1. Conclusions Our study provides a systems biology approach to how different molecular entities inter-connect with each other during the formation of an accumulation blastema in regenerating axolotl limbs. This approach provides an in silico methodology to identify proteins that are not detected by experimental methods such as proteomics but are potentially important to blastema formation. We found that the TFs, c-Myc and SP1 and their target genes could potentially play a central role in limb regeneration. Systems biology has the potential to map out numerous other pathways that are crucial to blastema formation in regeneration-competent limbs, to compare these to the pathways that characterize regeneration-deficient limbs and finally, to identify stem

  15. Mexican Revolution

    OpenAIRE

    Scheuzger, Stephan

    2016-01-01

    It was the complex and far-reaching transformation of the Mexican Revolution rather than the First World War that left its mark on Mexican history in the second decade of the 20th century. Nevertheless, although the country maintained its neutrality in the international conflict, it was a hidden theatre of war. Between 1914 and 1918, state actors in Germany, Great Britain and the United States defined their policies towards Mexico and its nationalist revolution with a view not only to improve...

  16. Transforming growth factor: beta signaling is essential for limb regeneration in axolotls.

    Directory of Open Access Journals (Sweden)

    Mathieu Lévesque

    2007-11-01

    Full Text Available Axolotls (urodele amphibians have the unique ability, among vertebrates, to perfectly regenerate many parts of their body including limbs, tail, jaw and spinal cord following injury or amputation. The axolotl limb is the most widely used structure as an experimental model to study tissue regeneration. The process is well characterized, requiring multiple cellular and molecular mechanisms. The preparation phase represents the first part of the regeneration process which includes wound healing, cellular migration, dedifferentiation and proliferation. The redevelopment phase represents the second part when dedifferentiated cells stop proliferating and redifferentiate to give rise to all missing structures. In the axolotl, when a limb is amputated, the missing or wounded part is regenerated perfectly without scar formation between the stump and the regenerated structure. Multiple authors have recently highlighted the similarities between the early phases of mammalian wound healing and urodele limb regeneration. In mammals, one very important family of growth factors implicated in the control of almost all aspects of wound healing is the transforming growth factor-beta family (TGF-beta. In the present study, the full length sequence of the axolotl TGF-beta1 cDNA was isolated. The spatio-temporal expression pattern of TGF-beta1 in regenerating limbs shows that this gene is up-regulated during the preparation phase of regeneration. Our results also demonstrate the presence of multiple components of the TGF-beta signaling machinery in axolotl cells. By using a specific pharmacological inhibitor of TGF-beta type I receptor, SB-431542, we show that TGF-beta signaling is required for axolotl limb regeneration. Treatment of regenerating limbs with SB-431542 reveals that cellular proliferation during limb regeneration as well as the expression of genes directly dependent on TGF-beta signaling are down-regulated. These data directly implicate TGF

  17. Proteinaceous Pheromone Homologs Identified from the Cloacal Gland Transcriptome of a Male Axolotl, Ambystoma mexicanum.

    Directory of Open Access Journals (Sweden)

    Kevin W Hall

    Full Text Available Pheromones play an important role in modifying vertebrate behavior, especially during courtship and mating. Courtship behavior in urodele amphibians often includes female exposure to secretions from the cloacal gland, as well as other scent glands. The first vertebrate proteinaceous pheromone discovered, the decapeptide sodefrin, is a female attracting pheromone secreted by the cloacal gland of male Cynops pyrrhogaster. Other proteinaceous pheromones in salamanders have been shown to elicit responses from females towards conspecific males. The presence and levels of expression of proteinaceous pheromones have not been identified in the family Ambystomatidae, which includes several important research models. The objective of this research was therefore to identify putative proteinaceous pheromones from male axolotls, Ambystoma mexicanum, as well as their relative expression levels. The results indicate that axolotls possess two different forms of sodefrin precursor-like factor (alpha and beta, as well as a putative ortholog of plethodontid modulating factor. The beta form of sodefrin precursor-like factor was amongst the most highly expressed transcripts within the cloacal gland. The ortholog of plethodontid modulating factor was expressed at a level equivalent to the beta sodefrin precursor-like factor. The results are from a single male axolotl; therefore, we are unable to assess how representative our results may be. Nevertheless, the presence of these highly expressed proteinaceous pheromones suggests that male axolotls use multiple chemical cues to attract female conspecifics. Behavioral assays would indicate whether the putative protein pheromones elicit courtship activity from female axolotls.

  18. Proteinaceous Pheromone Homologs Identified from the Cloacal Gland Transcriptome of a Male Axolotl, Ambystoma mexicanum.

    Science.gov (United States)

    Hall, Kevin W; Eisthen, Heather L; Williams, Barry L

    2016-01-01

    Pheromones play an important role in modifying vertebrate behavior, especially during courtship and mating. Courtship behavior in urodele amphibians often includes female exposure to secretions from the cloacal gland, as well as other scent glands. The first vertebrate proteinaceous pheromone discovered, the decapeptide sodefrin, is a female attracting pheromone secreted by the cloacal gland of male Cynops pyrrhogaster. Other proteinaceous pheromones in salamanders have been shown to elicit responses from females towards conspecific males. The presence and levels of expression of proteinaceous pheromones have not been identified in the family Ambystomatidae, which includes several important research models. The objective of this research was therefore to identify putative proteinaceous pheromones from male axolotls, Ambystoma mexicanum, as well as their relative expression levels. The results indicate that axolotls possess two different forms of sodefrin precursor-like factor (alpha and beta), as well as a putative ortholog of plethodontid modulating factor. The beta form of sodefrin precursor-like factor was amongst the most highly expressed transcripts within the cloacal gland. The ortholog of plethodontid modulating factor was expressed at a level equivalent to the beta sodefrin precursor-like factor. The results are from a single male axolotl; therefore, we are unable to assess how representative our results may be. Nevertheless, the presence of these highly expressed proteinaceous pheromones suggests that male axolotls use multiple chemical cues to attract female conspecifics. Behavioral assays would indicate whether the putative protein pheromones elicit courtship activity from female axolotls.

  19. Gene expression patterns specific to the regenerating limb of the Mexican axolotl

    Directory of Open Access Journals (Sweden)

    James R. Monaghan

    2012-07-01

    Salamander limb regeneration is dependent upon tissue interactions that are local to the amputation site. Communication among limb epidermis, peripheral nerves, and mesenchyme coordinate cell migration, cell proliferation, and tissue patterning to generate a blastema, which will form missing limb structures. An outstanding question is how cross-talk between these tissues gives rise to the regeneration blastema. To identify genes associated with epidermis-nerve-mesenchymal interactions during limb regeneration, we examined histological and transcriptional changes during the first week following injury in the wound epidermis and subjacent cells between three injury types; 1 a flank wound on the side of the animal that will not regenerate a limb, 2 a denervated limb that will not regenerate a limb, and 3 an innervated limb that will regenerate a limb. Early, histological and transcriptional changes were similar between the injury types, presumably because a common wound-healing program is employed across anatomical locations. However, some transcripts were enriched in limbs compared to the flank and are associated with vertebrate limb development. Many of these genes were activated before blastema outgrowth and expressed in specific tissue types including the epidermis, peripheral nerve, and mesenchyme. We also identified a relatively small group of transcripts that were more highly expressed in innervated limbs versus denervated limbs. These transcripts encode for proteins involved in myelination of peripheral nerves, epidermal cell function, and proliferation of mesenchymal cells. Overall, our study identifies limb-specific and nerve-dependent genes that are upstream of regenerative growth, and thus promising candidates for the regulation of blastema formation.

  20. Ambiguities in the relationship between gonadal steroids and reproduction in axolotls (Ambystoma mexicanum).

    Science.gov (United States)

    Eisthen, Heather L; Krause, Brianne Chung

    2012-05-01

    Axolotls (Ambystoma mexicanum) are aquatic salamanders that are widely used in research. Axolotls have been bred in laboratories for nearly 150 years, yet little is known about the basic biology of reproduction in these animals. We investigated the effects of changing day length, time of year, and food availability on levels of circulating estradiol and androgens in adult female and male axolotls, respectively. In addition, we examined the effects of these variables on the mass of ovaries, oviducts, and eggs in females and on mass of testes in males relative to each individual's body weight, to calculate a form of gonadosomatic index (GSI). In both sexes, GSI was not correlated with levels of circulating steroids. In female axolotls, estradiol levels were influenced by food availability, changes in day length, and season, even when animals were held at a constant temperature and day length was decorrelated with calendar date. In addition, the mass of ovaries, oviducts, and eggs varied seasonally, peaking in the winter months and declining during the summer months, even though our animals were not breeding and shedding eggs. In males, levels of androgens appeared to vary independently of external conditions, but GSI varied dramatically with changes in day length. These results suggest that reproduction in axolotls may vary seasonally, as it does in many other ambystomid species, although both male and female axolotls are capable of reproducing several times each year. The physiological basis of this ability remains enigmatic, given the indications of seasonality contained in our data. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. Musashi and Plasticity of Xenopus and Axolotl Spinal Cord Ependymal Cells

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    Ellen A. G. Chernoff

    2018-02-01

    Full Text Available The differentiated state of spinal cord ependymal cells in regeneration-competent amphibians varies between a constitutively active state in what is essentially a developing organism, the tadpole of the frog Xenopus laevis, and a quiescent, activatable state in a slowly growing adult salamander Ambystoma mexicanum, the Axolotl. Ependymal cells are epithelial in intact spinal cord of all vertebrates. After transection, body region ependymal epithelium in both Xenopus and the Axolotl disorganizes for regenerative outgrowth (gap replacement. Injury-reactive ependymal cells serve as a stem/progenitor cell population in regeneration and reconstruct the central canal. Expression patterns of mRNA and protein for the stem/progenitor cell-maintenance Notch signaling pathway mRNA-binding protein Musashi (msi change with life stage and regeneration competence. Msi-1 is missing (immunohistochemistry, or at very low levels (polymerase chain reaction, PCR, in both intact regeneration-competent adult Axolotl cord and intact non-regeneration-competent Xenopus tadpole (Nieuwkoop and Faber stage 62+, NF 62+. The critical correlation for successful regeneration is msi-1 expression/upregulation after injury in the ependymal outgrowth and stump-region ependymal cells. msi-1 and msi-2 isoforms were cloned for the Axolotl as well as previously unknown isoforms of Xenopus msi-2. Intact Xenopus spinal cord ependymal cells show a loss of msi-1 expression between regeneration-competent (NF 50–53 and non-regenerating stages (NF 62+ and in post-metamorphosis froglets, while msi-2 displays a lower molecular weight isoform in non-regenerating cord. In the Axolotl, embryos and juveniles maintain Msi-1 expression in the intact cord. In the adult Axolotl, Msi-1 is absent, but upregulates after injury. Msi-2 levels are more variable among Axolotl life stages: rising between late tailbud embryos and juveniles and decreasing in adult cord. Cultures of regeneration

  2. Musashi and Plasticity of Xenopus and Axolotl Spinal Cord Ependymal Cells

    Science.gov (United States)

    Chernoff, Ellen A. G.; Sato, Kazuna; Salfity, Hai V. N.; Sarria, Deborah A.; Belecky-Adams, Teri

    2018-01-01

    The differentiated state of spinal cord ependymal cells in regeneration-competent amphibians varies between a constitutively active state in what is essentially a developing organism, the tadpole of the frog Xenopus laevis, and a quiescent, activatable state in a slowly growing adult salamander Ambystoma mexicanum, the Axolotl. Ependymal cells are epithelial in intact spinal cord of all vertebrates. After transection, body region ependymal epithelium in both Xenopus and the Axolotl disorganizes for regenerative outgrowth (gap replacement). Injury-reactive ependymal cells serve as a stem/progenitor cell population in regeneration and reconstruct the central canal. Expression patterns of mRNA and protein for the stem/progenitor cell-maintenance Notch signaling pathway mRNA-binding protein Musashi (msi) change with life stage and regeneration competence. Msi-1 is missing (immunohistochemistry), or at very low levels (polymerase chain reaction, PCR), in both intact regeneration-competent adult Axolotl cord and intact non-regeneration-competent Xenopus tadpole (Nieuwkoop and Faber stage 62+, NF 62+). The critical correlation for successful regeneration is msi-1 expression/upregulation after injury in the ependymal outgrowth and stump-region ependymal cells. msi-1 and msi-2 isoforms were cloned for the Axolotl as well as previously unknown isoforms of Xenopus msi-2. Intact Xenopus spinal cord ependymal cells show a loss of msi-1 expression between regeneration-competent (NF 50–53) and non-regenerating stages (NF 62+) and in post-metamorphosis froglets, while msi-2 displays a lower molecular weight isoform in non-regenerating cord. In the Axolotl, embryos and juveniles maintain Msi-1 expression in the intact cord. In the adult Axolotl, Msi-1 is absent, but upregulates after injury. Msi-2 levels are more variable among Axolotl life stages: rising between late tailbud embryos and juveniles and decreasing in adult cord. Cultures of regeneration-competent Xenopus tadpole

  3. Esterases activity in the axolotl Ambystoma mexicanum exposed to chlorpyrifos and its implication to motor activity.

    Science.gov (United States)

    Robles-Mendoza, Cecilia; Zúñiga-Lagunes, Sebastian R; Ponce de León-Hill, Claudia A; Hernández-Soto, Jesús; Vanegas-Pérez, Cecilia

    2011-10-01

    The axolotl Ambystoma mexicanum is a neotenic salamander considered a good biological model due to its ability to regenerate limbs, tail, brain and heart cells. Nevertheless, severe reduction of A. mexicanum wild populations in the lacustrine area of Xochimilco, the natural habitat of the axolotl, could be related to several environmental pressures as the presence of organophosphate pesticides (OPPs), intensively applied in agricultural activities in Xochimilco. Thus the aim of this study was to evaluate the effect of environmentally realistic chlorpyrifos (CPF) concentrations, a OPP commonly used in this zone, on esterases activity (acetylcholinesterase and carboxylesterase) and bioconcentration of CPF and to relate them with the motor activity of A. mexicanum juveniles. Axolotls were exposed 48 h to 0.05 and 0.1mg CPF/L, and the responses were evaluated at the end of the CPF exposure. Results suggest that CPF is bioconcentrated into axolotls and that the CPF internal concentrations are related with the observed inhibition activity of AChE (>50%) and CbE (≈ 50%). CPF concentration responsible of the inhibition of the 50% of AChE activity (IC50) was estimated in 0.04 mg CPF/L; however IC50 for CbE activity was not possible to calculate since inhibition levels were lower than 50%, results that suggest a higher resistance of CbE enzymatic activity to CPF. However, motor activity was a more sensitive endpoint to CPF poisoning since time that axolotls spent active and walking, frequency and speed of swimming, frequency of prey attack were reduced >90% of control groups. The motor activity alterations in the axolotl could be related with the registered esterases inhibition. Thus important alterations on axolotls were identified even at short time and low concentrations of CPF exposure. Also, it was possible to link biochemical responses as esterases activity with higher levels of biological organization as behavior. This study provides tools for the regulation of the

  4. Axolotl/Bichos Raros Crónica

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    Susana Chávez-Silverman

    2012-11-01

    Full Text Available In this crónica, I pay homage (and talk back to! one of my favourite authors, Julio Cortázar, who I had the great privilege and pleasure of befriending in 1980, when he was a visiting professor at UC-Berkeley. I have been obsessed with time-travel, doubling, and interstitiality since I was very young; even the most casual Cortázar reader (if such a thing is possible will immediately recognise these as recurrent themes in his work. Here, faced with several actual axolotl in a Buenos Aires aquarium, I explore and comment on Cortázar’s strangely mesmerising meditation on identity and transformation. My personal connection is (as in much of my writing concerned with aspects of gender and sexuality suppressed or (more likely ignored in Cortázar’s version. I identify, too, with a poignant in-betweenness and ambiguity I read in the figure of the axolotl—and in the work of Cortázar and Alejandra Pizarnik.

  5. Organophosphorus pesticides effect on early stages of the axolotl Ambystoma mexicanum (Amphibia: Caudata).

    Science.gov (United States)

    Robles-Mendoza, C; García-Basilio, C; Cram-Heydrich, S; Hernández-Quiroz, M; Vanegas-Pérez, C

    2009-02-01

    Ambystoma mexicanum is an endemic salamander of Xochimilco, a wetland of the basin of Mexico valley. Nowadays, axolotl populations are decreasing due environmental stressors. Particularly, studies about organophosphorus pesticides (OPPs; i.e. chlorpyrifos and malathion) toxicity are of great importance due to their intensive use in agricultural activities in Xochimilco. Thus, the aim of this study was to evaluate under controlled conditions the toxicity of chlorpyrifos (CPF) and malathion (MLT) on embryos and larvae (stage 44 and 54) of A. mexicanum. Embryos and larvae were exposure 96h from 0.5 to 3mg CPFL(-1) and from 10 to 30mg MLTL(-1) in independent tests. Embryos at the end of this period were maintained 9d without pesticide in order to identify possible recuperation. Differences obtained in mortality, hatching success, development, morphological abnormalities, behaviour and activity, suggest that toxicity of CPF and MLT differs in embryos and larval stages. Embryos were less sensitive to OPPs acute exposure than axolotl larvae; additionally, toxicity of CPF in larval stages was greater than MLT. On the other hand, data obtained in axolotl embryos during the period of recuperation to CPF in particular as delay and inhibition of development, malformations and success of hatching, indicated that these responses turned out more sensitive than mortality. This study allowed to identify the toxicological potential of OPPs on early developmental stages of A. mexicanum and it is a valuable contribution for the future management of the axolotl wild population.

  6. Highly efficient targeted mutagenesis in axolotl using Cas9 RNA-guided nuclease

    Science.gov (United States)

    Flowers, G. Parker; Timberlake, Andrew T.; Mclean, Kaitlin C.; Monaghan, James R.; Crews, Craig M.

    2014-01-01

    Among tetrapods, only urodele salamanders, such as the axolotl Ambystoma mexicanum, can completely regenerate limbs as adults. The mystery of why salamanders, but not other animals, possess this ability has for generations captivated scientists seeking to induce this phenomenon in other vertebrates. Although many recent advances in molecular biology have allowed limb regeneration and tissue repair in the axolotl to be investigated in increasing detail, the molecular toolkit for the study of this process has been limited. Here, we report that the CRISPR-Cas9 RNA-guided nuclease system can efficiently create mutations at targeted sites within the axolotl genome. We identify individual animals treated with RNA-guided nucleases that have mutation frequencies close to 100% at targeted sites. We employ this technique to completely functionally ablate EGFP expression in transgenic animals and recapitulate developmental phenotypes produced by loss of the conserved gene brachyury. Thus, this advance allows a reverse genetic approach in the axolotl and will undoubtedly provide invaluable insight into the mechanisms of salamanders' unique regenerative ability. PMID:24764077

  7. Multiple regeneration from axolotl limb stumps bearing cross-transplanted minced muscle regenerates : brief note

    NARCIS (Netherlands)

    Carlson, Bruce M.

    Flexor and extensor muscles in the upper arms of axolotls were minced and cross-transplanted. The limbs were amputated 5 and 30 days after mincing. In each experiment a high percentage of the regenerates consisted of multiple limbs. This demonstrates that the morphogenetic information which produces

  8. Proteomic analysis of blastema formation in regenerating axolotl limbs

    Directory of Open Access Journals (Sweden)

    Nye Holly LD

    2009-11-01

    Full Text Available Abstract Background Following amputation, urodele salamander limbs reprogram somatic cells to form a blastema that self-organizes into the missing limb parts to restore the structure and function of the limb. To help understand the molecular basis of blastema formation, we used quantitative label-free liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS-based methods to analyze changes in the proteome that occurred 1, 4 and 7 days post amputation (dpa through the mid-tibia/fibula of axolotl hind limbs. Results We identified 309 unique proteins with significant fold change relative to controls (0 dpa, representing 10 biological process categories: (1 signaling, (2 Ca2+ binding and translocation, (3 transcription, (4 translation, (5 cytoskeleton, (6 extracellular matrix (ECM, (7 metabolism, (8 cell protection, (9 degradation, and (10 cell cycle. In all, 43 proteins exhibited exceptionally high fold changes. Of these, the ecotropic viral integrative factor 5 (EVI5, a cell cycle-related oncoprotein that prevents cells from entering the mitotic phase of the cell cycle prematurely, was of special interest because its fold change was exceptionally high throughout blastema formation. Conclusion Our data were consistent with previous studies indicating the importance of inositol triphosphate and Ca2+ signaling in initiating the ECM and cytoskeletal remodeling characteristic of histolysis and cell dedifferentiation. In addition, the data suggested that blastema formation requires several mechanisms to avoid apoptosis, including reduced metabolism, differential regulation of proapoptotic and antiapoptotic proteins, and initiation of an unfolded protein response (UPR. Since there is virtually no mitosis during blastema formation, we propose that high levels of EVI5 function to arrest dedifferentiated cells somewhere in the G1/S/G2 phases of the cell cycle until they have accumulated under the wound epidermis and enter mitosis in response to

  9. Expression of Msx-2 during development, regeneration, and wound healing in axolotl limbs.

    Science.gov (United States)

    Carlson, M R; Bryant, S V; Gardiner, D M

    1998-12-15

    Msx genes are transcription factors that are expressed during embryogenesis of developing appendages in regions of epithelial-mesenchymal interactions. Various lines of evidence indicate that these genes function to maintain embryonic tissues in an undifferentiated, proliferative state. We have identified the axolotl homolog of Msx-2, and investigated its expression during limb development, limb regeneration, and wound healing. As in limb buds of higher vertebrates, axolotl Msx-2 is expressed in the apical epidermis and mesenchyme; however, its expression domain is more extensive, reflecting the broader region of the apical epidermal cap in amphibians. Msx-2 expression is downregulated at late stages of limb development, but is reexpressed within one hour after limb amputation. Msx-2 is also reexpressed during wound healing, and may be essential in the early stages of initiation of the limb regeneration cascade.

  10. Comparative Analysis of Cartilage Marker Gene Expression Patterns during Axolotl and Xenopus Limb Regeneration.

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    Kazumasa Mitogawa

    Full Text Available Axolotls (Ambystoma mexicanum can completely regenerate lost limbs, whereas Xenopus laevis frogs cannot. During limb regeneration, a blastema is first formed at the amputation plane. It is thought that this regeneration blastema forms a limb by mechanisms similar to those of a developing embryonic limb bud. Furthermore, Xenopus laevis frogs can form a blastema after amputation; however, the blastema results in a terminal cone-shaped cartilaginous structure called a "spike." The causes of this patterning defect in Xenopus frog limb regeneration were explored. We hypothesized that differences in chondrogenesis may underlie the patterning defect. Thus, we focused on chondrogenesis. Chondrogenesis marker genes, type I and type II collagen, were compared in regenerative and nonregenerative environments. There were marked differences between axolotls and Xenopus in the expression pattern of these chondrogenesis-associated genes. The relative deficit in the chondrogenic capacity of Xenopus blastema cells may account for the absence of total limb regenerative capacity.

  11. Germline Transgenic Methods for Tracking Cells and Testing Gene Function during Regeneration in the Axolotl

    Science.gov (United States)

    Khattak, Shahryar; Schuez, Maritta; Richter, Tobias; Knapp, Dunja; Haigo, Saori L.; Sandoval-Guzmán, Tatiana; Hradlikova, Kristyna; Duemmler, Annett; Kerney, Ryan; Tanaka, Elly M.

    2013-01-01

    The salamander is the only tetrapod that regenerates complex body structures throughout life. Deciphering the underlying molecular processes of regeneration is fundamental for regenerative medicine and developmental biology, but the model organism had limited tools for molecular analysis. We describe a comprehensive set of germline transgenic strains in the laboratory-bred salamander Ambystoma mexicanum (axolotl) that open up the cellular and molecular genetic dissection of regeneration. We demonstrate tissue-dependent control of gene expression in nerve, Schwann cells, oligodendrocytes, muscle, epidermis, and cartilage. Furthermore, we demonstrate the use of tamoxifen-induced Cre/loxP-mediated recombination to indelibly mark different cell types. Finally, we inducibly overexpress the cell-cycle inhibitor p16INK4a, which negatively regulates spinal cord regeneration. These tissue-specific germline axolotl lines and tightly inducible Cre drivers and LoxP reporter lines render this classical regeneration model molecularly accessible. PMID:24052945

  12. Problems Faced by Mexican Asylum Seekers in the United States

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    J. Anna Cabot

    2014-12-01

    Full Text Available Violence in Mexico rose sharply in response to President Felipe Calderón’s military campaign against drug cartels which began in late 2006. As a consequence, the number of Mexicans who have sought asylum in the United States has grown significantly. In 2013, Mexicans made up the second largest group of defensive asylum seekers (those in removal proceedings in the United States, behind only China (EOIR 2014b. Yet between 2008 and 2013, the grant rate for Mexican asylum seekers in immigration court fell from 23 percent to nine percent (EOIR 2013, 2014b. This paper examines—from the perspective of an attorney who represented Mexican asylum seekers on the US-Mexico border in El Paso, Texas—the reasons for low asylum approval rates for Mexicans despite high levels of violence in and flight from Mexico from 2008 to 2013. It details the obstacles faced by Mexican asylum seekers along the US-Mexico border, including placement in removal proceedings, detention, evidentiary issues, narrow legal standards, and (effectively judicial notice of country conditions in Mexico. The paper recommends that asylum seekers at the border be placed in affirmative proceedings (before immigration officials, making them eligible for bond. It also proposes increased oversight of immigration judges.

  13. Problems Faced by Mexican Asylum Seekers in the United States

    OpenAIRE

    J. Anna Cabot

    2014-01-01

    Violence in Mexico rose sharply in response to President Felipe Calderón’s military campaign against drug cartels which began in late 2006. As a consequence, the number of Mexicans who have sought asylum in the United States has grown significantly. In 2013, Mexicans made up the second largest group of defensive asylum seekers (those in removal proceedings) in the United States, behind only China (EOIR 2014b). Yet between 2008 and 2013, the grant rate for Mexican asylum seekers in immigration...

  14. Regulation of Regenerative Responses by Factors in the Extracellular Matrix during Axolotl (Ambystoma mexicanum) Limb Regeneration

    OpenAIRE

    Phan, Anne Quy

    2014-01-01

    Salamanders are unique among adult vertebrates in their ability to regenerate complex body structures after traumatic injury. Axolotl limb regeneration is a stepwise sequence of three requisite processes: (1) scarless wound healing to generate a regenerative wound epithelium, (2) blastema formation by migration, proliferation and dedifferentiation to create a mass of multipotent regeneration-competent progenitor cells, and (3) induction of pattern formation by interaction of cells with opposi...

  15. Neural crest does not contribute to the neck and shoulder in the axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Epperlein, Hans-Henning; Khattak, Shahryar; Knapp, Dunja; Tanaka, Elly M; Malashichev, Yegor B

    2012-01-01

    A major step during the evolution of tetrapods was their transition from water to land. This process involved the reduction or complete loss of the dermal bones that made up connections to the skull and a concomitant enlargement of the endochondral shoulder girdle. In the mouse the latter is derived from three separate embryonic sources: lateral plate mesoderm, somites, and neural crest. The neural crest was suggested to sustain the muscle attachments. How this complex composition of the endochondral shoulder girdle arose during evolution and whether it is shared by all tetrapods is unknown. Salamanders that lack dermal bone within their shoulder girdle were of special interest for a possible contribution of the neural crest to the endochondral elements and muscle attachment sites, and we therefore studied them in this context. We grafted neural crest from GFP+ fluorescent transgenic axolotl (Ambystoma mexicanum) donor embryos into white (d/d) axolotl hosts and followed the presence of neural crest cells within the cartilage of the shoulder girdle and the connective tissue of muscle attachment sites of the neck-shoulder region. Strikingly, neural crest cells did not contribute to any part of the endochondral shoulder girdle or to the connective tissue at muscle attachment sites in axolotl. Our results in axolotl suggest that neural crest does not serve a general function in vertebrate shoulder muscle attachment sites as predicted by the "muscle scaffold theory," and that it is not necessary to maintain connectivity of the endochondral shoulder girdle to the skull. Our data support the possibility that the contribution of the neural crest to the endochondral shoulder girdle, which is observed in the mouse, arose de novo in mammals as a developmental basis for their skeletal synapomorphies. This further supports the hypothesis of an increased neural crest diversification during vertebrate evolution.

  16. Neural crest does not contribute to the neck and shoulder in the axolotl (Ambystoma mexicanum.

    Directory of Open Access Journals (Sweden)

    Hans-Henning Epperlein

    Full Text Available BACKGROUND: A major step during the evolution of tetrapods was their transition from water to land. This process involved the reduction or complete loss of the dermal bones that made up connections to the skull and a concomitant enlargement of the endochondral shoulder girdle. In the mouse the latter is derived from three separate embryonic sources: lateral plate mesoderm, somites, and neural crest. The neural crest was suggested to sustain the muscle attachments. How this complex composition of the endochondral shoulder girdle arose during evolution and whether it is shared by all tetrapods is unknown. Salamanders that lack dermal bone within their shoulder girdle were of special interest for a possible contribution of the neural crest to the endochondral elements and muscle attachment sites, and we therefore studied them in this context. RESULTS: We grafted neural crest from GFP+ fluorescent transgenic axolotl (Ambystoma mexicanum donor embryos into white (d/d axolotl hosts and followed the presence of neural crest cells within the cartilage of the shoulder girdle and the connective tissue of muscle attachment sites of the neck-shoulder region. Strikingly, neural crest cells did not contribute to any part of the endochondral shoulder girdle or to the connective tissue at muscle attachment sites in axolotl. CONCLUSIONS: Our results in axolotl suggest that neural crest does not serve a general function in vertebrate shoulder muscle attachment sites as predicted by the "muscle scaffold theory," and that it is not necessary to maintain connectivity of the endochondral shoulder girdle to the skull. Our data support the possibility that the contribution of the neural crest to the endochondral shoulder girdle, which is observed in the mouse, arose de novo in mammals as a developmental basis for their skeletal synapomorphies. This further supports the hypothesis of an increased neural crest diversification during vertebrate evolution.

  17. Pathological changes of Golgi complex in hemocytoblasts of spleen of young axolotls after x-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Turska, R.

    1975-01-01

    The data available up to now concerning the structure of Golgi complex in different types of normal and pathologically changed cells are very divergent. Results are reported from detailed studies on changes occurring within the Golgi complex in the spleen of three-month old axolotls after x-ray irradiation with a single dose of 1,200 R and killed by decapitation 15, 30, 60 minutes and 3, 6, and 12 hours after irradiation.

  18. Expression of Msx genes in regenerating and developing limbs of axolotl.

    Science.gov (United States)

    Koshiba, K; Kuroiwa, A; Yamamoto, H; Tamura, K; Ide, H

    1998-12-15

    Msx genes, homeobox-containing genes, have been isolated as homologues of the Drosophila msh gene and are thought to play important roles in the development of chick or mouse limb buds. We isolated two Msx genes, Msx1 and Msx2, from regenerating blastemas of axolotl limbs and examined their expression patterns using Northern blot and whole mount in situ hybridization during regeneration and development. Northern blot analysis revealed that the expression level of both Msx genes increased during limb regeneration. The Msx2 expression level increased in the blastema at the early bud stage, and Msx1 expression level increased at the late bud stage. Whole mount in situ hybridization revealed that Msx2 was expressed in the distal mesenchyme and Msx1 in the entire mesenchyme of the blastema at the late bud stage. In the developing limb bud, Msx1 was expressed in the entire mesenchyme, while Msx2 was expressed in the distal and peripheral mesenchyme. The expression patterns of Msx genes in the blastemas and limb buds of the axolotl were different from those reported for chick or mouse limb buds. These expression patterns of axolotl Msx genes are discussed in relation to the blastema or limb bud morphology and their possible roles in limb patterning.

  19. Linking vertebral number to performance of aquatic escape responses in the axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Ackerly, Kerri L; Ward, Andrea B

    2015-12-01

    Environmental conditions during early development in ectothermic vertebrates can lead to variation in vertebral number among individuals of the same species. It is often seen that individuals of a species raised at cooler temperatures have more vertebrae than individuals raised at warmer temperatures, although the functional consequences of this variation in vertebral number on swimming performance are relatively unclear. To investigate this relationship, we tested how vertebral number in axolotls (Ambystoma mexicanum) affected performance of aquatic escape responses (C-starts). Axolotls were reared at four temperatures (12-24°C) encompassing their natural thermal range and then transitioned to a mean temperature (18°C) three months before C-starts were recorded. Our results showed variation in vertebral number, but that variation was not significantly affected by developmental temperature. C-start performance among axolotls was significantly correlated with caudal vertebral number, and individuals with more caudal vertebrae were able to achieve greater curvature more quickly during their responses than individuals with fewer vertebrae. However, our results show that these individuals did not achieve greater displacements or velocities, and that developmental temperature did not have any effect on C-start performance. We highlight that the most important aspects of escape swim performance (i.e., how far individuals get from a threat and how quickly they move the most important parts of the body away from that threat) are consistent across individuals regardless of developmental temperature and morphological variation. Copyright © 2015 Elsevier GmbH. All rights reserved.

  20. Efficient gene knockin in axolotl and its use to test the role of satellite cells in limb regeneration.

    Science.gov (United States)

    Fei, Ji-Feng; Schuez, Maritta; Knapp, Dunja; Taniguchi, Yuka; Drechsel, David N; Tanaka, Elly M

    2017-11-21

    Salamanders exhibit extensive regenerative capacities and serve as a unique model in regeneration research. However, due to the lack of targeted gene knockin approaches, it has been difficult to label and manipulate some of the cell populations that are crucial for understanding the mechanisms underlying regeneration. Here we have established highly efficient gene knockin approaches in the axolotl ( Ambystoma mexicanum ) based on the CRISPR/Cas9 technology. Using a homology-independent method, we successfully inserted both the Cherry reporter gene and a larger membrane-tagged Cherry-ER T2 -Cre-ER T2 (∼5-kb) cassette into axolotl Sox2 and Pax7 genomic loci. Depending on the size of the DNA fragments for integration, 5-15% of the F0 transgenic axolotl are positive for the transgene. Using these techniques, we have labeled and traced the PAX7-positive satellite cells as a major source contributing to myogenesis during axolotl limb regeneration. Our work brings a key genetic tool to molecular and cellular studies of axolotl regeneration.

  1. Mexican Parenting Questionnaire (MPQ)

    Science.gov (United States)

    Halgunseth, Linda C.; Ispa, Jean M.

    2012-01-01

    The present study was conducted in four phases and constructed a self-report parenting instrument for use with Mexican immigrant mothers of children aged 6 to 10. The 14-item measure was based on semistructured qualitative interviews with Mexican immigrant mothers (N = 10), was refined by a focus group of Mexican immigrant mothers (N = 5), and was…

  2. Ultrastructure of the renal juxtaglomerular complex and peripolar cells in the axolotl (Ambystoma mexicanum) and toad (Bufo marinus).

    Science.gov (United States)

    Hanner, R H; Ryan, G B

    1980-01-01

    Renal juxtaglomerular regions were examined in the axolotl (Ambystoma mexicanum and toad (Bufo marinus). Prominent granulated peripolar epithelial cells were found surrounding the origin of the glomerular tuft in the axolotl. These cells resembled the peripolar cells recently discovered in mammalian species. They contained multiple electron-dense cytoplasmic granules, some of which showed a paracrystalline substructure and signs of exocytoxic activity. Such cells were difficult to find and smaller in the toad. In contrast, granulated juxtaglomerular arteriolar myoephithelial cells were much more readily found and larger in the toad than in the axolotl. No consistent differences were noted in juxtaglomerular cells or their granules in response to changes in environmental chloride concentration. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 PMID:7410189

  3. De novo transcriptome sequencing of axolotl blastema for identification of differentially expressed genes during limb regeneration

    Science.gov (United States)

    2013-01-01

    Background Salamanders are unique among vertebrates in their ability to completely regenerate amputated limbs through the mediation of blastema cells located at the stump ends. This regeneration is nerve-dependent because blastema formation and regeneration does not occur after limb denervation. To obtain the genomic information of blastema tissues, de novo transcriptomes from both blastema tissues and denervated stump ends of Ambystoma mexicanum (axolotls) 14 days post-amputation were sequenced and compared using Solexa DNA sequencing. Results The sequencing done for this study produced 40,688,892 reads that were assembled into 307,345 transcribed sequences. The N50 of transcribed sequence length was 562 bases. A similarity search with known proteins identified 39,200 different genes to be expressed during limb regeneration with a cut-off E-value exceeding 10-5. We annotated assembled sequences by using gene descriptions, gene ontology, and clusters of orthologous group terms. Targeted searches using these annotations showed that the majority of the genes were in the categories of essential metabolic pathways, transcription factors and conserved signaling pathways, and novel candidate genes for regenerative processes. We discovered and confirmed numerous sequences of the candidate genes by using quantitative polymerase chain reaction and in situ hybridization. Conclusion The results of this study demonstrate that de novo transcriptome sequencing allows gene expression analysis in a species lacking genome information and provides the most comprehensive mRNA sequence resources for axolotls. The characterization of the axolotl transcriptome can help elucidate the molecular mechanisms underlying blastema formation during limb regeneration. PMID:23815514

  4. Microarray Analysis of microRNA Expression during Axolotl Limb Regeneration

    Science.gov (United States)

    Holman, Edna C.; Campbell, Leah J.; Hines, John; Crews, Craig M.

    2012-01-01

    Among vertebrates, salamanders stand out for their remarkable capacity to quickly regrow a myriad of tissues and organs after injury or amputation. The limb regeneration process in axolotls (Ambystoma mexicanum) has been well studied for decades at the cell-tissue level. While several developmental genes are known to be reactivated during this epimorphic process, less is known about the role of microRNAs in urodele amphibian limb regeneration. Given the compelling evidence that many microRNAs tightly regulate cell fate and morphogenetic processes through development and adulthood by modulating the expression (or re-expression) of developmental genes, we investigated the possibility that microRNA levels change during limb regeneration. Using two different microarray platforms to compare the axolotl microRNA expression between mid-bud limb regenerating blastemas and non-regenerating stump tissues, we found that miR-21 was overexpressed in mid-bud blastemas compared to stump tissue. Mature A. mexicanum (“Amex”) miR-21 was detected in axolotl RNA by Northern blot and differential expression of Amex-miR-21 in blastema versus stump was confirmed by quantitative RT-PCR. We identified the Amex Jagged1 as a putative target gene for miR-21 during salamander limb regeneration. We cloned the full length 3′UTR of Amex-Jag1, and our in vitro assays demonstrated that its single miR-21 target recognition site is functional and essential for the response of the Jagged1 gene to miR-21 levels. Our findings pave the road for advanced in vivo functional assays aimed to clarify how microRNAs such as miR-21, often linked to pathogenic cell growth, might be modulating the redeployment of developmental genes such as Jagged1 during regenerative processes. PMID:23028429

  5. Excretory nitrogen metabolism in the juvenile axolotl Ambystoma mexicanum: differences in aquatic and terrestrial environments.

    Science.gov (United States)

    Loong, Ai M; Chew, Shit F; Ip, Yuen K

    2002-01-01

    The fully grown but nonmetamorphosed (juvenile) axolotl Ambystoma mexicanum was ureogenic and primarily ureotelic in water. A complete ornithine-urea cycle (OUC) was present in the liver. Aerial exposure impeded urea (but not ammonia) excretion, leading to a decrease in the percentage of nitrogen excreted as urea in the first 24 h. However, urea and not ammonia accumulated in the muscle, liver, and plasma during aerial exposure. By 48 h, the rate of urea excretion recovered fully, probably due to the greater urea concentration gradient in the kidney. It is generally accepted that an increase in carbamoyl phosphate synthetase activity is especially critical in the developmental transition from ammonotelism to ureotelism in the amphibian. Results from this study indicate that such a transition in A. mexicanum would have occurred before migration to land. Aerial exposure for 72 h exhibited no significant effect on carbamoyl phosphate synthetase-I activity or that of other OUC enzymes (with the exception of ornithine transcarbamoylase) from the liver of the juvenile A. mexicanum. This supports our hypothesis that the capacities of OUC enzymes present in the liver of the aquatic juvenile axolotl were adequate to prepare it for its invasion of the terrestrial environment. The high OUC capacity was further supported by the capability of the juvenile A. mexicanum to survive in 10 mM NH(4)Cl without accumulating amino acids in its body. The majority of the accumulating endogenous and exogenous ammonia was detoxified to urea, which led to a greater than twofold increase in urea levels in the muscle, liver, and plasma and a significant increase in urea excretion by hour 96. Hence, it can be concluded that the juvenile axolotl acquired ureotelism while submerged in water, and its hepatic capacity of urea synthesis was more than adequate to handle the toxicity of endogenous ammonia during migration to land.

  6. Microarray analysis of microRNA expression during axolotl limb regeneration.

    Directory of Open Access Journals (Sweden)

    Edna C Holman

    Full Text Available Among vertebrates, salamanders stand out for their remarkable capacity to quickly regrow a myriad of tissues and organs after injury or amputation. The limb regeneration process in axolotls (Ambystoma mexicanum has been well studied for decades at the cell-tissue level. While several developmental genes are known to be reactivated during this epimorphic process, less is known about the role of microRNAs in urodele amphibian limb regeneration. Given the compelling evidence that many microRNAs tightly regulate cell fate and morphogenetic processes through development and adulthood by modulating the expression (or re-expression of developmental genes, we investigated the possibility that microRNA levels change during limb regeneration. Using two different microarray platforms to compare the axolotl microRNA expression between mid-bud limb regenerating blastemas and non-regenerating stump tissues, we found that miR-21 was overexpressed in mid-bud blastemas compared to stump tissue. Mature A. mexicanum ("Amex" miR-21 was detected in axolotl RNA by Northern blot and differential expression of Amex-miR-21 in blastema versus stump was confirmed by quantitative RT-PCR. We identified the Amex Jagged1 as a putative target gene for miR-21 during salamander limb regeneration. We cloned the full length 3'UTR of Amex-Jag1, and our in vitro assays demonstrated that its single miR-21 target recognition site is functional and essential for the response of the Jagged1 gene to miR-21 levels. Our findings pave the road for advanced in vivo functional assays aimed to clarify how microRNAs such as miR-21, often linked to pathogenic cell growth, might be modulating the redeployment of developmental genes such as Jagged1 during regenerative processes.

  7. Analysis of embryonic development in the unsequenced axolotl: waves of transcriptomic upheaval and stability

    Science.gov (United States)

    Jiang, Peng; Nelson, Jeffrey D.; Leng, Ning; Collins, Michael; Swanson, Scott; Dewey, Colin N.; Thomson, James A.; Stewart, Ron

    2016-01-01

    The axolotl (Ambystoma mexicanum) has long been the subject of biological research, primarily owing to its outstanding regenerative capabilities. However, the gene expression programs governing its embryonic development are particularly underexplored, especially when compared to other amphibian model species. Therefore, we performed whole transcriptome polyA+ RNA sequencing experiments on 17 stages of embryonic development. As the axolotl genome is unsequenced and its gene annotation is incomplete, we built de novo transcriptome assemblies for each stage and garnered functional annotation by comparing expressed contigs with known genes in other organisms. In evaluating the number of differentially expressed genes over time, we identify three waves of substantial transcriptome upheaval each followed by a period of relative transcriptome stability. The first wave of upheaval is between the one and two cell stage. We show that the number of differentially expressed genes per unit time is higher between the one and two cell stage than it is across the mid-blastula transition (MBT), the period of zygotic genome activation. We use total RNA sequencing to demonstrate that the vast majority of genes with increasing polyA+ signal between the one and two cell stage result from polyadenylation rather than de novo transcription. The first stable phase begins after the two cell stage and continues until the mid-blastula transition, corresponding with the pre-MBT phase of transcriptional quiescence in amphibian development. Following this is a peak of differential gene expression corresponding with the activation of the zygotic genome and a phase of transcriptomic stability from stages 9 to 11. We observe a third wave of transcriptomic change between stages 11 and 14, followed by a final stable period. The last two stable phases have not been documented in amphibians previously and correspond to times of major morphogenic change in the axolotl embryo: gastrulation and

  8. Comparative RNA-seq analysis in the unsequenced axolotl: the oncogene burst highlights early gene expression in the blastema.

    Directory of Open Access Journals (Sweden)

    Ron Stewart

    Full Text Available The salamander has the remarkable ability to regenerate its limb after amputation. Cells at the site of amputation form a blastema and then proliferate and differentiate to regrow the limb. To better understand this process, we performed deep RNA sequencing of the blastema over a time course in the axolotl, a species whose genome has not been sequenced. Using a novel comparative approach to analyzing RNA-seq data, we characterized the transcriptional dynamics of the regenerating axolotl limb with respect to the human gene set. This approach involved de novo assembly of axolotl transcripts, RNA-seq transcript quantification without a reference genome, and transformation of abundances from axolotl contigs to human genes. We found a prominent burst in oncogene expression during the first day and blastemal/limb bud genes peaking at 7 to 14 days. In addition, we found that limb patterning genes, SALL genes, and genes involved in angiogenesis, wound healing, defense/immunity, and bone development are enriched during blastema formation and development. Finally, we identified a category of genes with no prior literature support for limb regeneration that are candidates for further evaluation based on their expression pattern during the regenerative process.

  9. Functional characterization of the vertebrate primary ureter: Structure and ion transport mechanisms of the pronephric duct in axolotl larvae (Amphibia)

    DEFF Research Database (Denmark)

    Haugan, Birgitte M; Halberg, Kenneth Agerlin; Jespersen, Åse

    2010-01-01

    whether the duct is involved in urine modification using larvae of the freshwater amphibian Ambystoma mexicanum (axolotl) as model. Results We investigated structural as well as physiological properties of the pronephric duct. The key elements of our methodology were: using histology, light...

  10. [Specific growth rate and the rate of energy metabolism in the ontogenesis of axolotl, Ambystoma mexicanum (Amphibia: Ambystomatidae)].

    Science.gov (United States)

    Vladimirova, I G; Kleĭmenov, S Iu; Alekseeva, T A; Radzinskaia, L I

    2003-01-01

    Concordant changes in the rate of energy metabolism and specific growth rate of axolotls have been revealed. Several periods of ontogeny are distinguished, which differ in the ratio of energy metabolism to body weight and, therefore, are described by different allometric equations. It is suggested that the specific growth rate of an animal determines the type of dependence of energy metabolism on body weight.

  11. The effects of rotation and positional change of stump tissues upon morphogenesis of the regenerating axolotl limb

    NARCIS (Netherlands)

    Carlson, Bruce M.

    1972-01-01

    Rotation of a skin cuff 180° around the proximodistal axis of the upper arm in the axolotl results in the formation of multiple regenerates in about 80° of cases after amputation of the limb through the rotated skin. Rotation of the dermis or the flexor and extensor muscles folowed by amputation

  12. Mexican Society of Bioelectromagnetism

    International Nuclear Information System (INIS)

    Canedo, Luis

    2008-01-01

    In July 2007 physicians, biologists and physicists that have collaborated in previous meetings of the medical branch of the Mexican Physical Society constituted the Mexican Society of Bioelectromagnetism with the purpose of promote scientific study of the interaction of electromagnetic energy (at frequencies ranging from zero Hertz through those of visible light) and acoustic energy with biological systems. A second goal was to increase the contribution of medical and biological professionals in the meetings of the medical branch of the Mexican Physical Society. The following paragraphs summarize some objectives of the Mexican Society of Bioelectromagnetism for the next two years

  13. Terminal-Nerve-Derived Neuropeptide Y Modulates Physiological Responses in the Olfactory Epithelium of Hungry Axolotls (Ambystoma mexicanum)

    Science.gov (United States)

    Mousley, Angela; Polese, Gianluca; Marks, Nikki J.; Eisthen, Heather L.

    2007-01-01

    The vertebrate brain actively regulates incoming sensory information, effectively filtering input and focusing attention toward environmental stimuli that are most relevant to the animal's behavioral context or physiological state. Such centrifugal modulation has been shown to play an important role in processing in the retina and cochlea, but has received relatively little attention in olfaction. The terminal nerve, a cranial nerve that extends underneath the lamina propria surrounding the olfactory epithelium, displays anatomical and neurochemical characteristics that suggest that it modulates activity in the olfactory epithelium. Using immunocytochemical techniques, we demonstrate that neuropeptide Y (NPY) is abundantly present in the terminal nerve in the axolotl (Ambystoma mexicanum), an aquatic salamander. Because NPY plays an important role in regulating appetite and hunger in many vertebrates, we investigated the possibility that NPY modulates activity in the olfactory epithelium in relation to the animal's hunger level. We therefore characterized the full length NPY gene from axolotls to enable synthesis of authentic axolotl NPY for use in electrophysiological experiments. We find that axolotl NPY modulates olfactory epithelial responses evoked by L-glutamic acid, a food-related odorant, but only in hungry animals. Similarly, whole-cell patch-clamp recordings demonstrate that bath application of axolotl NPY enhances the magnitude of a tetrodotoxin-sensitive inward current, but only in hungry animals. These results suggest that expression or activity of NPY receptors in the olfactory epithelium may change with hunger level, and that terminal nerve-derived peptides modulate activity in the olfactory epithelium in response to an animal's changing behavioral and physiological circumstances. PMID:16855098

  14. Terminal nerve-derived neuropeptide y modulates physiological responses in the olfactory epithelium of hungry axolotls (Ambystoma mexicanum).

    Science.gov (United States)

    Mousley, Angela; Polese, Gianluca; Marks, Nikki J; Eisthen, Heather L

    2006-07-19

    The vertebrate brain actively regulates incoming sensory information, effectively filtering input and focusing attention toward environmental stimuli that are most relevant to the animal's behavioral context or physiological state. Such centrifugal modulation has been shown to play an important role in processing in the retina and cochlea, but has received relatively little attention in olfaction. The terminal nerve, a cranial nerve that extends underneath the lamina propria surrounding the olfactory epithelium, displays anatomical and neurochemical characteristics that suggest that it modulates activity in the olfactory epithelium. Using immunocytochemical techniques, we demonstrate that neuropeptide Y (NPY) is abundantly present in the terminal nerve in the axolotl (Ambystoma mexicanum), an aquatic salamander. Because NPY plays an important role in regulating appetite and hunger in many vertebrates, we investigated the possibility that NPY modulates activity in the olfactory epithelium in relation to the animal's hunger level. We therefore characterized the full-length NPY gene from axolotls to enable synthesis of authentic axolotl NPY for use in electrophysiological experiments. We find that axolotl NPY modulates olfactory epithelial responses evoked by l-glutamic acid, a food-related odorant, but only in hungry animals. Similarly, whole-cell patch-clamp recordings demonstrate that bath application of axolotl NPY enhances the magnitude of a tetrodotoxin-sensitive inward current, but only in hungry animals. These results suggest that expression or activity of NPY receptors in the olfactory epithelium may change with hunger level, and that terminal nerve-derived peptides modulate activity in the olfactory epithelium in response to an animal's changing behavioral and physiological circumstances.

  15. Live Imaging of Axolotl Digit Regeneration Reveals Spatiotemporal Choreography of Diverse Connective Tissue Progenitor Pools.

    Science.gov (United States)

    Currie, Joshua D; Kawaguchi, Akane; Traspas, Ricardo Moreno; Schuez, Maritta; Chara, Osvaldo; Tanaka, Elly M

    2016-11-21

    Connective tissues-skeleton, dermis, pericytes, fascia-are a key cell source for regenerating the patterned skeleton during axolotl appendage regeneration. This complexity has made it difficult to identify the cells that regenerate skeletal tissue. Inability to identify these cells has impeded a mechanistic understanding of blastema formation. By tracing cells during digit tip regeneration using brainbow transgenic axolotls, we show that cells from each connective tissue compartment have distinct spatial and temporal profiles of proliferation, migration, and differentiation. Chondrocytes proliferate but do not migrate into the regenerate. In contrast, pericytes proliferate, then migrate into the blastema and give rise solely to pericytes. Periskeletal cells and fibroblasts contribute the bulk of digit blastema cells and acquire diverse fates according to successive waves of migration that choreograph their proximal-distal and tissue contributions. We further show that platelet-derived growth factor signaling is a potent inducer of fibroblast migration, which is required to form the blastema. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  16. The axolotl limb blastema: cellular and molecular mechanisms driving blastema formation and limb regeneration in tetrapods

    Science.gov (United States)

    McCusker, Catherine; Bryant, Susan V.

    2015-01-01

    Abstract The axolotl is one of the few tetrapods that are capable of regenerating complicated biological structures, such as complete limbs, throughout adulthood. Upon injury the axolotl generates a population of regeneration‐competent limb progenitor cells known as the blastema, which will grow, establish pattern, and differentiate into the missing limb structures. In this review we focus on the crucial early events that occur during wound healing, the neural−epithelial interactions that drive the formation of the early blastema, and how these mechanisms differ from those of other species that have restricted regenerative potential, such as humans. We also discuss how the presence of cells from the different axes of the limb is required for the continued growth and establishment of pattern in the blastema as described in the polar coordinate model, and how this positional information is reprogrammed in blastema cells during regeneration. Multiple cell types from the mature limb stump contribute to the blastema at different stages of regeneration, and we discuss the contribution of these types to the regenerate with reference to whether they are “pattern‐forming” or “pattern‐following” cells. Lastly, we explain how an engineering approach will help resolve unanswered questions in limb regeneration, with the goal of translating these concepts to developing better human regenerative therapies. PMID:27499868

  17. Abdominal Distension Associated with Luminal Fungi in the Intestines of Axolotl Larvae

    Directory of Open Access Journals (Sweden)

    Chiara Zullian

    2015-01-01

    Full Text Available Axolotls show a remarkable regeneration capacity compared with higher vertebrates, regenerating missing appendages such as limbs and tail as well as other body parts (i.e., apex of the heart, forebrain, and jaw after amputations which makes this animal a very interesting research model for tissue regeneration mechanisms. Larvae are individually housed in a 20% Holtfreter’s solution within clear plastic containers. The photoperiod light : darkness cycle is 12 : 12 h. Larvae with a total body length of less than 5 cm are fed once a day with large brine shrimp and blood worm. Albino larvae appeared to have a tendency to exhibit abdominal distention. No clinical signs of illness seemed to be associated with the condition; however, these animals exhibit a relatively slower growth rate. To better characterize this condition, we performed histological sectioning for cross sectional slide preparation on wild type and albino axolotl larvae following euthanasia. The only lesion seen in the albino larvae was a thickened gut wall and the presence of fungi within the intestines. We hypothesize that this may be due to a lower efficacy of the albino larvae’s immune system.

  18. On the participation of irradiated tissues in the formation of limb regenerate in axolotls

    International Nuclear Information System (INIS)

    Tuchkova, S.Ya.

    1976-01-01

    The aim of the study was to obtain further information on the participation of irradiated tissue cells in formation of regenerated limbs after X-irradiation of axolotls and experimental restoration of the regenerational ability. Cells of irradiated tissues were labeled with H 3 -thymidine; the presence of the label in regenerated tissues would be indicative of participation of irradiated cells in the regeneration process. Irradiation dose was 700 R. 30 axolotls with irradiated limbs were intramuscularly injected with rat muscle homogenate into the right limb once a day beginning from the day of treatment. 15 similarly irradiated animals which did not receive homogenate served as a control. The authors concluded that the presence of highly labeled cells in regenerated tissues was likely to indicate the participation of irradiated tissue cells in regeneration of the limb. However, the quantitative contribution of such cells was impossible to determine since remaining irradiated tissues of the organ contained mostly unlabeled cells. It was also impossible to rule out the possibility of cell migration from non-irradiated tissues [ru

  19. Ultrastructure of the external gill epithelium of the axolotl, Ambystoma mexicanum with reference to ionic transport.

    Science.gov (United States)

    Jarial, M S; Wilkins, J H

    2003-10-01

    The ultrastructure of the external gill epithelium of the axolotl, Ambystoma mexicanum, has been examined using conventional transmission electron microscopy to elucidate its role in ionic transport. Four cell types are identified in the gill filament and primary gill bar epithelium. These are granular, ciliated, Leydig and basal cells. A fifth cell type, the flat mitochondria-rich cell is only found in the gill bar epithelium. The predominant granular cells display microvilli at their surface and their cytoplasm contains abundant mitochondria, rough endoplasmic reticulum, Golgi complexes, vesicles and PAS+ secretory granules that are extruded at the surface, which along with secretions from the Leydig cells form a mucous coat. The granular cells are joined apically by junctional complexes consisting of zonulae occludens, zonulae adherens and desmosomes. The lateral membranes of granular cells enclose large intercellular spaces that are closed at the apical ends but remain open at the basal ends adjoining capillaries. In AgNO3-treated axolotl, the gills become darkly stained, the silver grains penetrate apical membranes and appear in the cytoplasm, accumulating near the lateral membranes and also enter the intercellular spaces. These findings are consistent with the dual role of the gill epithelium in mucus production and active ionic transport.

  20. Cutaneous mastocytomas in the neotenic caudate amphibians Ambystoma mexicanum (axolotl) and Ambystoma tigrinun (tiger salamander)

    Science.gov (United States)

    Harshbarger, J.C.; Chang, S.C.; DeLanney, L.E.; Rose, F.L.; Green, D.E.

    1999-01-01

    Spontaneous mastocytomas studied in 18 axolotls (Ambystoma mexicanum) and six tiger salamanders (Ambystoma tigrinum) were gray-white, uni- to multilobular cutaneous protrusions from 2mm to 2cm in diameter. Tumors were moderately cellular unencapsulated masses that usually infiltrated the dermis and hypodermis with the destruction of intervening tissues. Some tumors were invading superficial bundles of the underlying skeletal muscle. Tumors consisted of mitotically active cells derived from a single lineage but showing a range of differentiation. Immature cells had nearly smooth to lightly cleft or folded basophilic nuclei bordered by a band of cytoplasm with few cytoplasmic processes and containing a few small uniform eccentric granules. Mature cells had basophilic nuclei with deep clefts or folds and abundant eosinophilic cytoplasm with multiple long intertwining cytoplasmic extensions packed with metachromatic granules. The axolotls were old individuals from an inbred laboratory colony. The tiger salamanders were wild animals from a single polluted pond. They could have been old and inbred. Both groups were neotenic. These are the first mastocytomas discovered in cold-blooded animals.

  1. Dual embryonic origin and patterning of the pharyngeal skeleton in the axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Sefton, Elizabeth M; Piekarski, Nadine; Hanken, James

    2015-01-01

    The impressive morphological diversification of vertebrates was achieved in part by innovation and modification of the pharyngeal skeleton. Extensive fate mapping in amniote models has revealed a primarily cranial neural crest derivation of the pharyngeal skeleton. Although comparable fate maps of amphibians produced over several decades have failed to document a neural crest derivation of ventromedial elements in these vertebrates, a recent report provides evidence of a mesodermal origin of one of these elements, basibranchial 2, in the axolotl. We used a transgenic labeling protocol and grafts of labeled cells between GFP+ and white embryos to derive a fate map that describes contributions of both cranial neural crest and mesoderm to the axolotl pharyngeal skeleton, and we conducted additional experiments that probe the mechanisms that underlie mesodermal patterning. Our fate map confirms a dual embryonic origin of the pharyngeal skeleton in urodeles, including derivation of basibranchial 2 from mesoderm closely associated with the second heart field. Additionally, heterotopic transplantation experiments reveal lineage restriction of mesodermal cells that contribute to pharyngeal cartilage. The mesoderm-derived component of the pharyngeal skeleton appears to be particularly sensitive to retinoic acid (RA): administration of exogenous RA leads to loss of the second basibranchial, but not the first. Neural crest was undoubtedly critical in the evolution of the vertebrate pharyngeal skeleton, but mesoderm may have played a central role in forming ventromedial elements, in particular. When and how many times during vertebrate phylogeny a mesodermal contribution to the pharyngeal skeleton evolved remain to be resolved. © 2015 Wiley Periodicals, Inc.

  2. Evidence for an RNA polymerization activity in axolotl and Xenopus egg extracts.

    Directory of Open Access Journals (Sweden)

    Hélène Pelczar

    2010-12-01

    Full Text Available We have previously reported a post-transcriptional RNA amplification observed in vivo following injection of in vitro synthesized transcripts into axolotl oocytes, unfertilized (UFE or fertilized eggs. To further characterize this phenomenon, low speed extracts (LSE from axolotl and Xenopus UFE were prepared and tested in an RNA polymerization assay. The major conclusions are: i the amphibian extracts catalyze the incorporation of radioactive ribonucleotide in RNase but not DNase sensitive products showing that these products correspond to RNA; ii the phenomenon is resistant to α-amanitin, an inhibitor of RNA polymerases II and III and to cordycepin (3'dAMP, but sensitive to cordycepin 5'-triphosphate, an RNA elongation inhibitor, which supports the existence of an RNA polymerase activity different from polymerases II and III; the detection of radiolabelled RNA comigrating at the same length as the exogenous transcript added to the extracts allowed us to show that iii the RNA polymerization is not a 3' end labelling and that iv the radiolabelled RNA is single rather than double stranded. In vitro cell-free systems derived from amphibian UFE therefore validate our previous in vivo results hypothesizing the existence of an evolutionary conserved enzymatic activity with the properties of an RNA dependent RNA polymerase (RdRp.

  3. Explanatory Emotion Talk in Mexican Immigrant and Mexican American Families.

    Science.gov (United States)

    Cervantes, Christi A.

    2002-01-01

    Mother-child conversations during story-telling play were analyzed for patterns of emotion talk. Subjects were 48 Mexican immigrant and Mexican American mothers and their children aged 3-4. Contrary to previous findings, Mexican immigrant mothers used more explanations of emotions than labels. Mexican American mothers used both, equally. Results…

  4. The Mexican American.

    Science.gov (United States)

    Rowan, Helen

    The purpose of this paper, prepared for the U. S. Commission on Civil Rights, is to indicate the types and ranges of problems facing the Mexican American community and to suggest ways in which these problems are peculiar to Mexican Americans. Specific examples are cited to illustrate major problems and personal experiences. Topics covered in the…

  5. Mexican Perspectives on Mexican-U.S. Relations

    Science.gov (United States)

    1993-04-01

    while serving in the United States military, working in the Bracero program and in American factories. By working with Americans, Mexicans learned that...Mexican government blames the problem on the United States. During the history of the Bracero Program (1942 -1964) 4.6 million Mexicans traveled to...and became familiar to Mexican migrants.ŕ The termination of the Bracero Program did not discourage Mexican agricultural workers from entering the

  6. The Mexican oil industry

    International Nuclear Information System (INIS)

    Marcos-Giacoman, E.

    1991-01-01

    In the environment of growing domestic demand and enhanced international competitiveness, Petroleos Mexicanos (PEMEX)-the Mexican national oil company-faces the challenge of not only responding adequately to the rapid changes taking place in the Mexican economy, but making a significant contribution towards solid and stable growth. This paper reports that the relevant concern is how PEMEX is going to live up to these expectations. The Mexican oil industry, especially including the petrochemical sector, has great potential in terms of an ample domestic market as well as external foreign-currency-generating markets

  7. Positional information in axolotl and mouse limb extracellular matrix is mediated via heparan sulfate and fibroblast growth factor during limb regeneration in the axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Phan, Anne Q; Lee, Jangwoo; Oei, Michelle; Flath, Craig; Hwe, Caitlyn; Mariano, Rachele; Vu, Tiffany; Shu, Cynthia; Dinh, Andrew; Simkin, Jennifer; Muneoka, Ken; Bryant, Susan V; Gardiner, David M

    2015-08-01

    Urodele amphibians are unique among adult vertebrates in their ability to regenerate complex body structures after traumatic injury. In salamander regeneration, the cells maintain a memory of their original position and use this positional information to recreate the missing pattern. We used an in vivo gain-of-function assay to determine whether components of the extracellular matrix (ECM) have positional information required to induce formation of new limb pattern during regeneration. We discovered that salamander limb ECM has a position-specific ability to either inhibit regeneration or induce de novo limb structure, and that this difference is dependent on heparan sulfates that are associated with differential expression of heparan sulfate sulfotransferases. We also discovered that an artificial ECM containing only heparan sulfate was sufficient to induce de novo limb pattern in salamander limb regeneration. Finally, ECM from mouse limbs is capable of inducing limb pattern in axolotl blastemas in a position-specific, developmental-stage-specific, and heparan sulfate-dependent manner. This study demonstrates a mechanism for positional information in regeneration and establishes a crucial functional link between salamander regeneration and mammals.

  8. Severe necrotizing myocarditis caused by serratia marcescens infection in an axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Del-Pozo, J; Girling, S; Pizzi, R; Mancinelli, E; Else, R W

    2011-05-01

    This report provides the first account of the pathological changes associated with infection by Serratia marcescens in an adult male axolotl. The infection resulted in septicaemia with severe multifocal necrotizing myocarditis. The latter lesion evolved to cardiac rupture, haemopericardium and death resulting from cardiac tamponade. This animal was exposed to higher than usual temperatures (24-25 °C) 2 weeks before the onset of disease and this may have resulted in immunocompromise and opportunistic bacterial infection. S. marcescens was isolated from the coelomic and pericardial cavity. Both isolates were identical and were resistant to β-lactam antibiotics, but not to aminoglycosides or fluoroquinolones. The production of red prodigiosin pigment by the bacterium suggested an environmental origin. Overall, the clinical and histopathological presentation suggests that S. marcescens should be included in the list of aetiological agents of the 'red-leg'/bacterial dermatosepticaemia syndrome of amphibians. Copyright © 2010 Elsevier Ltd. All rights reserved.

  9. Lineage tracing of genome-edited alleles reveals high fidelity axolotl limb regeneration.

    Science.gov (United States)

    Flowers, Grant Parker; Sanor, Lucas D; Crews, Craig M

    2017-09-16

    Salamanders are unparalleled among tetrapods in their ability to regenerate many structures, including entire limbs, and the study of this ability may provide insights into human regenerative therapies. The complex structure of the limb poses challenges to the investigation of the cellular and molecular basis of its regeneration. Using CRISPR/Cas, we genetically labelled unique cell lineages within the developing axolotl embryo and tracked the frequency of each lineage within amputated and fully regenerated limbs. This allowed us, for the first time, to assess the contributions of multiple low frequency cell lineages to the regenerating limb at once. Our comparisons reveal that regenerated limbs are high fidelity replicas of the originals even after repeated amputations.

  10. Induction of Metamorphosis Causes Differences in Sex-Specific Allocation Patterns in Axolotls (Ambystoma mexicanum) that Have Different Growth Histories.

    Science.gov (United States)

    Clarkson, Pamela M; Beachy, Christopher K

    2015-12-01

    We tested the hypothesis that salamanders growing at different rates would have allocation patterns that differ among male and female metamorphic and larval salamanders. We raised individual axolotls, Ambystoma mexicanum , on four food regimes: constant high growth (throughout the experiment), constant low growth (restricted throughout the experiment), high growth switched to low growth (ad libitum switched after 140 d to restricted), and low growth switched to high growth (restricted switched after 140 d to ad libitum). Because axolotls are obligate paedomorphs, we exposed half of the salamanders to thyroid hormone to induce metamorphosis. We assayed growth and dissected and weighed gonads and fat bodies. Salamanders that were switched from restricted to ad libitum food regime delayed metamorphosis. In all treatment groups, females had larger gonads than males and males had larger fat bodies than females. The association between storage and reproduction differed between larvae and metamorphs and depended on sex.

  11. Proliferation zones in the axolotl brain and regeneration of the telencephalon

    Directory of Open Access Journals (Sweden)

    Maden Malcolm

    2013-01-01

    Full Text Available Abstract Background Although the brains of lower vertebrates are known to exhibit somewhat limited regeneration after incisional or stab wounds, the Urodele brain exhibits extensive regeneration after massive tissue removal. Discovering whether and how neural progenitor cells that reside in the ventricular zones of Urodeles proliferate to mediate tissue repair in response to injury may produce novel leads for regenerative strategies. Here we show that endogenous neural progenitor cells resident to the ventricular zone of Urodeles spontaneously proliferate, producing progeny that migrate throughout the telencephalon before terminally differentiating into neurons. These progenitor cells appear to be responsible for telencephalon regeneration after tissue removal and their activity may be up-regulated by injury through an olfactory cue. Results There is extensive proliferation of endogenous neural progenitor cells throughout the ventricular zone of the adult axolotl brain. The highest levels are observed in the telencephalon, especially the dorsolateral aspect, and cerebellum. Lower levels are observed in the mesencephalon and rhombencephalon. New cells produced in the ventricular zone migrate laterally, dorsally and ventrally into the surrounding neuronal layer. After migrating from the ventricular zone, the new cells primarily express markers of neuronal differentiative fates. Large-scale telencephalic tissue removal stimulates progenitor cell proliferation in the ventricular zone of the damaged region, followed by proliferation in the tissue that surrounds the healing edges of the wound until the telencephalon has completed regeneration. The proliferative stimulus appears to reside in the olfactory system, because telencephalic regeneration does not occur in the brains of olfactory bulbectomized animals in which the damaged neural tissue simply heals over. Conclusion There is a continual generation of neuronal cells from neural progenitor cells

  12. Collection of gametes from live axolotl, Ambystoma mexicanum, and standardization of in vitro fertilization.

    Science.gov (United States)

    Mansour, N; Lahnsteiner, F; Patzner, R A

    2011-01-15

    This study established the first protocol for collection of gametes from live axolotl, Ambystoma mexicanum, by gentle abdominal massage and in vitro fertilization. To stimulate spermiation and ovulation, human chorionic gonadotrophin (hCG) and Ovopel pellets, which are commercially used to stimulate spawning in fish, were tested. The hCG was more effective than Ovopel pellets and yielded a higher semen volume in the injected males and a shorter response time in the females. Collected semen by this method was already motile and fertile. Fertile eggs could be collected in 3-4 successive collection times after the female has started the typical spawning behaviour. The fertilization condition that yielded the highest hatching rate was mixing semen with eggs before the addition of a fertilization saline solution (20 mmol/l NaCl, 1 mmol/l KCl, 1 mmol/l Mg(2)SO(4), 1 mmol Ca(2)Cl, 3 mmol NaHCO(3), 10 mmol/l Tris, pH 8.5 - Osmolality = 65 mosmol/kg). When the pH of the fertilization solution was increased to ≥ 10, the hatching rate was significantly increased. The use of fertilization solutions with osmolalities of ≥ 150 and ≥ 182 were accompanied with a significant decrease in hatching rates and the appearance of deformed larvae, respectively. In conclusion, a reliable protocol for gamete collection from live axolotl is established as a laboratory model of in vitro fertilization for urodele amphibians. This protocol may be transferable to endangered urodeles. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. Proceedings of the 4. National Congress of the Mexican Society of Radiological Safety C.A; Memorias del 4. Congreso Nacional de Sociedad Mexicana de Seguridad Radiologica A.C

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1991-07-01

    In these sessions it had the participation of personalities of diverse internationally grateful organizations, with exhibitions about the situation of the nuclear industry of power, the applications of the radiations and the radiological safety in the international context. Also its were presented works about Emergency plans in Nuclear facilities and plants, Nuclear medicine, Food processing, Thermal neutrons, Neutron dosimetry, Charged particles, Thermoluminescence, Industrial radiography, Radiation monitoring, all of them with the participation of specialists with international prestige. The 41 works that are presented in the technical sessions come from Spanish, Brazilian, Greek and Mexican grateful institutions. All they are a sample of the intense activity in investigation and development in the areas of the nuclear industry as of the radiological safety. This congress reveals the impulse that the nuclear community grants to the formation of human resources.

  14. Proceedings of the 7th National Congress of the Mexican Society of Radiological Safety C.A.; Memorias del 7. Congreso Nacional de Sociedad Mexicana de Seguridad Radiologica A.C.

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-09-01

    The Mexican Society of Radiological Safety, celebrates on this time the 100 Anniversary of the radioactivity discovery, phenomenon coined by Marie Curie in 1898 and discover by Henry Beckerel in March 1896, when both were working with natural radioactive isotopes. Subsequently, on the new age of Physics, the use of radioactive isotopes was impulse by the invention of Cyclotron made by Dr. Ernest Orland Lawrence in the United States, which permits the manufacturing of tens of artificial radioactive isotopes which convert its in an indispensable tool in Medicine, Industry, Research, Agriculture and other disciplines, by its wide variety of applications, creating the radiological safety culture by the implicit risk in the use of these materials. From its creation in 1976, our society was removing to promote the radiological safety and two years each celebrates its National Congress removing specialists in this discipline and invite new generations to awake their interest by this useful field. (Author).

  15. Metamorfosis: La animalidad y el mito en La Metamorfosis de Kafka y Axolotl de Cortázar

    Directory of Open Access Journals (Sweden)

    Catalina Villalobos Díaz

    2017-07-01

    Full Text Available El presente artículo propone una lectura de la animalidad, principalmente de la metamorfosis, por medio de dos relatos de dos grandes escritores de la literatura: Axolotl, de Julio Cortázar, y La Metamorfosis, de Franz Kafka. A través de estos textos, se plantea un análisis con respecto a lo que representa una transformación y el mito tras la metamorfosis como tal.

  16. Molecular cloning, sequence analysis and homology modeling of the first caudata amphibian antifreeze-like protein in axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Zhang, Songyan; Gao, Jiuxiang; Lu, Yiling; Cai, Shasha; Qiao, Xue; Wang, Yipeng; Yu, Haining

    2013-08-01

    Antifreeze proteins (AFPs) refer to a class of polypeptides that are produced by certain vertebrates, plants, fungi, and bacteria and which permit their survival in subzero environments. In this study, we report the molecular cloning, sequence analysis and three-dimensional structure of the axolotl antifreeze-like protein (AFLP) by homology modeling of the first caudate amphibian AFLP. We constructed a full-length spleen cDNA library of axolotl (Ambystoma mexicanum). An EST having highest similarity (∼42%) with freeze-responsive liver protein Li16 from Rana sylvatica was identified, and the full-length cDNA was subsequently obtained by RACE-PCR. The axolotl antifreeze-like protein sequence represents an open reading frame for a putative signal peptide and the mature protein composed of 93 amino acids. The calculated molecular mass and the theoretical isoelectric point (pl) of this mature protein were 10128.6 Da and 8.97, respectively. The molecular characterization of this gene and its deduced protein were further performed by detailed bioinformatics analysis. The three-dimensional structure of current AFLP was predicted by homology modeling, and the conserved residues required for functionality were identified. The homology model constructed could be of use for effective drug design. This is the first report of an antifreeze-like protein identified from a caudate amphibian.

  17. Molecular cloning, sequence analysis and phylogeny of first caudata g-type lysozyme in axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Yu, Haining; Gao, Jiuxiang; Lu, Yiling; Guang, Huijuan; Cai, Shasha; Zhang, Songyan; Wang, Yipeng

    2013-11-01

    Lysozymes are key proteins that play important roles in innate immune defense in many animal phyla by breaking down the bacterial cell-walls. In this study, we report the molecular cloning, sequence analysis and phylogeny of the first caudate amphibian g-lysozyme: a full-length spleen cDNA library from axolotl (Ambystoma mexicanum). A goose-type (g-lysozyme) EST was identified and the full-length cDNA was obtained using RACE-PCR. The axolotl g-lysozyme sequence represents an open reading frame for a putative signal peptide and the mature protein composed of 184 amino acids. The calculated molecular mass and the theoretical isoelectric point (pl) of this mature protein are 21523.0 Da and 4.37, respectively. Expression of g-lysozyme mRNA is predominantly found in skin, with lower levels in spleen, liver, muscle, and lung. Phylogenetic analysis revealed that caudate amphibian g-lysozyme had distinct evolution pattern for being juxtaposed with not only anura amphibian, but also with the fish, bird and mammal. Although the first complete cDNA sequence for caudate amphibian g-lysozyme is reported in the present study, clones encoding axolotl's other functional immune molecules in the full-length cDNA library will have to be further sequenced to gain insight into the fundamental aspects of antibacterial mechanisms in caudate.

  18. BMP-2 functions independently of SHH signaling and triggers cell condensation and apoptosis in regenerating axolotl limbs

    Directory of Open Access Journals (Sweden)

    Finnson Kenneth

    2010-02-01

    Full Text Available Abstract Background Axolotls have the unique ability, among vertebrates, to perfectly regenerate complex body parts, such as limbs, after amputation. In addition, axolotls pattern developing and regenerating autopods from the anterior to posterior axis instead of posterior to anterior like all tetrapods studied to date. Sonic hedgehog is important in establishing this anterior-posterior axis of limbs in all tetrapods including axolotls. Interestingly, its expression is conserved (to the posterior side of limb buds and blastemas in axolotl limbs as in other tetrapods. It has been suggested that BMP-2 may be the secondary mediator of sonic hedgehog, although there is mounting evidence to the contrary in mice. Since BMP-2 expression is on the anterior portion of developing and regenerating limbs prior to digit patterning, opposite to the expression of sonic hedgehog, we examined whether BMP-2 expression was dependent on sonic hedgehog signaling and whether it affects patterning of the autopod during regeneration. Results The expression of BMP-2 and SOX-9 in developing and regenerating axolotl limbs corresponded to the first digits forming in the anterior portion of the autopods. The inhibition of sonic hedgehog signaling with cyclopamine caused hypomorphic limbs (during development and regeneration but did not affect the expression of BMP-2 and SOX-9. Overexpression of BMP-2 in regenerating limbs caused a loss of digits. Overexpression of Noggin (BMP inhibitor in regenerating limbs also resulted in a loss of digits. Histological analysis indicated that the loss due to BMP-2 overexpression was the result of increased cell condensation and apoptosis while the loss caused by Noggin was due to a decrease in cell division. Conclusion The expression of BMP-2 and its target SOX-9 was independent of sonic hedgehog signaling in developing and regenerating limbs. Their expression correlated with chondrogenesis and the appearance of skeletal elements has

  19. What's Values Got to Do with It? Thriving among Mexican/Mexican American College Students

    Science.gov (United States)

    Morgan Consoli, Melissa L.; Llamas, Jasmín; Consoli, Andrés J.

    2016-01-01

    The authors examined traditional Mexican/Mexican American and perceived U.S. mainstream cultural values as predictors of thriving. One hundred twenty-four (37 men, 87 women) self-identified Mexican/Mexican American college students participated in the study. The traditional Mexican/Mexican American cultural values of family support and religion…

  20. Supersymmetry: proceedings

    International Nuclear Information System (INIS)

    Brennan, E.C.

    1985-07-01

    Some lectures in these proceedings examine the theoretical basis for supersymmetry, recent developments in theories with compact dimensions, and experimental searches for supersymmetric signatures. Technologies are explored for obtaining very high energy electron-positron colliding beams. Separate abstracts were prepared for 35 papers in these conference proceedings

  1. Supersymmetry: proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Brennan, E.C. (ed.)

    1985-07-01

    Some lectures in these proceedings examine the theoretical basis for supersymmetry, recent developments in theories with compact dimensions, and experimental searches for supersymmetric signatures. Technologies are explored for obtaining very high energy electron-positron colliding beams. Separate abstracts were prepared for 35 papers in these conference proceedings. (LEW)

  2. Mexican Folkart for Children.

    Science.gov (United States)

    Dominguez, Graciela; And Others

    Directions, suggested materials, and illustrations are given for making paper mache pinatas and masks, cascarones, Ojos de Dios, maracas, dresser scarf embroidery, burlap murals, yarn designs, paper plate trays, paper cut designs, the poppy, sarape aprons, and paper Mexican dolls. Filled with candy and broken, the pinata is used on most Mexican…

  3. Mexican Identification. Project Mexico.

    Science.gov (United States)

    Castellano, Rita

    This document presents an outline and teacher's guide for a community college-level teaching module in Mexican identification, designed for students in introductory courses in the social sciences. Although intended specifically for cultural anthropology, urban anthropology, comparative social organization and sex roles in cross-cultural…

  4. Comparative transcriptional profiling of the axolotl limb identifies a tripartite regeneration-specific gene program.

    Directory of Open Access Journals (Sweden)

    Dunja Knapp

    Full Text Available Understanding how the limb blastema is established after the initial wound healing response is an important aspect of regeneration research. Here we performed parallel expression profile time courses of healing lateral wounds versus amputated limbs in axolotl. This comparison between wound healing and regeneration allowed us to identify amputation-specific genes. By clustering the expression profiles of these samples, we could detect three distinguishable phases of gene expression - early wound healing followed by a transition-phase leading to establishment of the limb development program, which correspond to the three phases of limb regeneration that had been defined by morphological criteria. By focusing on the transition-phase, we identified 93 strictly amputation-associated genes many of which are implicated in oxidative-stress response, chromatin modification, epithelial development or limb development. We further classified the genes based on whether they were or were not significantly expressed in the developing limb bud. The specific localization of 53 selected candidates within the blastema was investigated by in situ hybridization. In summary, we identified a set of genes that are expressed specifically during regeneration and are therefore, likely candidates for the regulation of blastema formation.

  5. Neurotrophic regulation of epidermal dedifferentiation during wound healing and limb regeneration in the axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Satoh, A; Graham, G M C; Bryant, S V; Gardiner, D M

    2008-07-15

    Adult urodeles (salamanders) are unique in their ability to regenerate complex organs perfectly. The recently developed Accessory Limb Model (ALM) in the axolotl provides an opportunity to identify and characterize the essential signaling events that control the early steps in limb regeneration. The ALM demonstrates that limb regeneration progresses in a stepwise fashion that is dependent on signals from the wound epidermis, nerves and dermal fibroblasts from opposite sides of the limb. When all the signals are present, a limb is formed de novo. The ALM thus provides an opportunity to identify and characterize the signaling pathways that control blastema morphogenesis and limb regeneration. In the present study, we have utilized the ALM to identity the buttonhead-like zinc-finger transcription factor, Sp9, as being involved in the formation of the regeneration epithelium. Sp9 expression is induced in basal keratinocytes of the apical blastema epithelium in a pattern that is comparable to its expression in developing limb buds, and it thus is an important marker for dedifferentiation of the epidermis. Induction of Sp9 expression is nerve-dependent, and we have identified KGF as an endogenous nerve factor that induces expression of Sp9 in the regeneration epithelium.

  6. Ex vivo generation of a functional and regenerative wound epithelium from axolotl (Ambystoma mexicanum) skin.

    Science.gov (United States)

    Ferris, Donald R; Satoh, Akira; Mandefro, Berhan; Cummings, Gillian M; Gardiner, David M; Rugg, Elizabeth L

    2010-10-01

    Urodele amphibians (salamanders) are unique among adult vertebrates in their ability to regenerate structurally complete and fully functional limbs. Regeneration is a stepwise process that requires interactions between keratinocytes, nerves and fibroblasts. The formation of a wound epithelium covering the amputation site is an early and necessary event in the process but the molecular mechanisms that underlie the role of the wound epithelium in regeneration remain unclear. We have developed an ex vivo model that recapitulates many features of in vivo wound healing. The model comprises a circular explant of axolotl (Ambystoma mexicanum) limb skin with a central circular, full thickness wound. Re-epithelialization of the wound area is rapid (typically <11 h) and is dependent on metalloproteinase activity. The ex vivo wound epithelium is viable, responds to neuronal signals and is able to participate in ectopic blastema formation and limb regeneration. This ex vivo model provides a reproducible and tractable system in which to study the cellular and molecular events that underlie wound healing and regeneration. © 2010 The Authors. Journal compilation © 2010 Japanese Society of Developmental Biologists.

  7. DNA Methylation Dynamics Regulate the Formation of a Regenerative Wound Epithelium during Axolotl Limb Regeneration.

    Directory of Open Access Journals (Sweden)

    Cristian Aguilar

    Full Text Available The formation of a blastema during regeneration of an axolotl limb involves important changes in the behavior and function of cells at the site of injury. One of the earliest events is the formation of the wound epithelium and subsequently the apical epidermal cap, which involves in vivo dedifferentiation that is controlled by signaling from the nerve. We have investigated the role of epigenetic modifications to the genome as a possible mechanism for regulating changes in gene expression patterns of keratinocytes of the wound and blastema epithelium that are involved in regeneration. We report a modulation of the expression DNMT3a, a de novo DNA methyltransferase, within the first 72 hours post injury that is dependent on nerve signaling. Treatment of skin wounds on the upper forelimb with decitabine, a DNA methyltransferase inhibitor, induced changes in gene expression and cellular behavior associated with a regenerative response. Furthermore, decitabine-treated wounds were able to participate in regeneration while untreated wounds inhibited a regenerative response. Elucidation of the specific epigenetic modifications that mediate cellular dedifferentiation likely will lead to insights for initiating a regenerative response in organisms that lack this ability.

  8. Neurotrophic regulation of fibroblast dedifferentiation during limb skeletal regeneration in the axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Satoh, Akira; Cummings, Gillian M C; Bryant, Susan V; Gardiner, David M

    2010-01-15

    The ability of animals to repair tissue damage is widespread and impressive. Among tissues, the repair and remodeling of bone occurs during growth and in response to injury; however, loss of bone above a threshold amount is not regenerated, resulting in a "critical-size defect" (CSD). The development of therapies to replace or regenerate a CSD is a major focus of research in regenerative medicine and tissue engineering. Adult urodeles (salamanders) are unique in their ability to regenerate complex tissues perfectly, yet like mammals do not regenerate a CSD. We report on an experimental model for the regeneration of a CSD in the axolotl (the Excisional Regeneration Model) that allows for the identification of signals to induce fibroblast dedifferentiation and skeletal regeneration. This regenerative response is mediated in part by BMP signaling, as is the case in mammals; however, a complete regenerative response requires the induction of a population of undifferentiated, regeneration-competent cells. These cells can be induced by signaling from limb amputation to generate blastema cells that can be grafted to the wound, as well as by signaling from a nerve and a wound epithelium to induce blastema cells from fibroblasts within the wound environment. Copyright 2009 Elsevier Inc. All rights reserved.

  9. Absence of mutation at the 5'-upstream promoter region of the TPM4 gene from cardiac mutant axolotl (Ambystoma mexicanum).

    Science.gov (United States)

    Denz, Christopher R; Zhang, Chi; Jia, Pingping; Du, Jianfeng; Huang, Xupei; Dube, Syamalima; Thomas, Anish; Poiesz, Bernard J; Dube, Dipak K

    2011-09-01

    Tropomyosins are a family of actin-binding proteins that show cell-specific diversity by a combination of multiple genes and alternative RNA splicing. Of the 4 different tropomyosin genes, TPM4 plays a pivotal role in myofibrillogenesis as well as cardiac contractility in amphibians. In this study, we amplified and sequenced the upstream regulatory region of the TPM4 gene from both normal and mutant axolotl hearts. To identify the cis-elements that are essential for the expression of the TPM4, we created various deletion mutants of the TPM4 promoter DNA, inserted the deleted segments into PGL3 vector, and performed promoter-reporter assay using luciferase as the reporter gene. Comparison of sequences of the promoter region of the TPM4 gene from normal and mutant axolotl revealed no mutations in the promoter sequence of the mutant TPM4 gene. CArG box elements that are generally involved in controlling the expression of several other muscle-specific gene promoters were not found in the upstream regulatory region of the TPM4 gene. In deletion experiments, loss of activity of the reporter gene was noted upon deletion which was then restored upon further deletion suggesting the presence of both positive and negative cis-elements in the upstream regulatory region of the TPM4 gene. We believe that this is the first axolotl promoter that has ever been cloned and studied with clear evidence that it functions in mammalian cell lines. Although striated muscle-specific cis-acting elements are absent from the promoter region of TPM4 gene, our results suggest the presence of positive and negative cis-elements in the promoter region, which in conjunction with positive and negative trans-elements may be involved in regulating the expression of TPM4 gene in a tissue-specific manner.

  10. Fine structure of the epidermal Leydig cells in the axolotl Ambystoma mexicanum in relation to their function.

    Science.gov (United States)

    Jarial, M S

    1989-01-01

    The fine structure of the Leydig cells in the epidermis of the strictly aquatic adult axolotl Ambystoma mexicanum resembles that of similar cells in larval salamanders. The major finding of this study is that the mucous secretion of the Leydig cells is released into the intercellular spaces from which it is discharged through pores onto the surface of the epidermis where it forms a mucous layer to protect the skin. Images Figs. 1-2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Figs. 11-13 PMID:2630544

  11. Proceedings of the 9 annual conference of the Mexican association for the energy economy. The energy security; 7. Conferencia anual de la asociacion mexicana para la economia energetica. seguridad energetica

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    The Asociacion Mexicana para la Economia Energetica (Mexican Association for the Energy Economy) summoned by the ninth occasion to its annual congress under the subject Power Assurance with the objective of analyzing the Power Assurance of Mexico in terms of general accessibility to power resources, of reliable and total availability of these, and their acceptability in relation to the environment; analysis from which recommendations of power policy will be derived. Six panels were constituted around the following analysis points: The geopolitical surroundings, certainties and uncertainties - where the irruption of new Asian demanding countries is analyzed, the uncertain continuity of provisions in Europe and the new power Latin American nationalism as tension centers and new areas of stressfulness are also analyzed -, energy Balances and markets in the American continent - focused on the type of anticipated evolution of the availability of oil and natural gas in Mexico along with its processing capacity -, Assurance of raw materials for the electrical generation - in direct relation with the present and future availability of own conventional resources, the characteristics and behavior of energy international markets of primary energy sources and of the access to technologies such as nuclear power stations-. Assurance of raw materials for the transport and the industry - focused on the resolution of the bottle necks that sometimes its availability is put under -. The energy assurance and the medium and long term development - knowing that the energy sector in Mexico is co-dependent and the decision making with respect to its financing must be based on realities and not in fantasies -, Policies for the power assurance - where a summary is presented, conclusions and recommendations of energy policy; the medium and long term attention requires to be initiated now. [Spanish] La Asociacion Mexicana para la Economia Energetica convoco por novena ocasion a su congreso

  12. Role of thyroid hormones in the normal and glucocorticosteroid hormone-induced evolution of carbamoyl-phosphate synthase (ammonia) activity in axolotl liver

    NARCIS (Netherlands)

    Lamers, W. H.; Vink, C.; Charles, R.

    1978-01-01

    1. In axolotl liver, the activity of carbamoyl-phosphate synthase (ammonia), expressed per mg liver protein, decreases to a minimum at 5 months of age, then increases to a maximum at 8 months of age which is followed by a decrease again. The initial decrease between 3 and 5 months of age appears to

  13. Contaminated Mexican steel incident

    International Nuclear Information System (INIS)

    1985-01-01

    This report documents the circumstances contributing to the inadvertent melting of cobalt 60 (Co-60) contaminated scrap metal in two Mexican steel foundries and the subsequent distribution of contaminated steel products into the United States. The report addresses mainly those actions taken by US Federal and state agencies to protect the US population from radiation risks associated with the incident. Mexico had much more serious radiation exposure and contamination problems to manage. The United States Government maintained a standing offer to provide technical and medical assistance to the Mexican Government. The report covers the tracing of the source to its origin, response actions to recover radioactive steel in the United States, and return of the contaminated materials to Mexico. The incident resulted in significant radiation exposures within Mexico, but no known significant exposure within the United States. Response to the incident required the combined efforts of the Nuclear Regulatory Commission (NRC), Department of Energy, Department of Transportation, Department of State, and US Customs Service (Department of Treasury) personnel at the Federal level and representatives of all 50 State Radiation Control Programs and, in some instances, local and county government personnel. The response also required a diplomatic interface with the Mexican Government and cooperation of numerous commercial establishments and members of the general public. The report describes the factual information associated with the event and may serve as information for subsequent recommendations and actions by the NRC. 8 figures

  14. Ion channel signaling influences cellular proliferation and phagocyte activity during axolotl tail regeneration.

    Science.gov (United States)

    Franklin, Brandon M; Voss, S Randal; Osborn, Jeffrey L

    2017-08-01

    Little is known about the potential for ion channels to regulate cellular behaviors during tissue regeneration. Here, we utilized an amphibian tail regeneration assay coupled with a chemical genetic screen to identify ion channel antagonists that altered critical cellular processes during regeneration. Inhibition of multiple ion channels either partially (anoctamin1/Tmem16a, anoctamin2/Tmem16b, K V 2.1, K V 2.2, L-type Ca V channels and H/K ATPases) or completely (GlyR, GABA A R, K V 1.5 and SERCA pumps) inhibited tail regeneration. Partial inhibition of tail regeneration by blocking the calcium activated chloride channels, anoctamin1&2, was associated with a reduction of cellular proliferation in tail muscle and mesenchymal regions. Inhibition of anoctamin 1/2 also altered the post-amputation transcriptional response of p44/42 MAPK signaling pathway genes, including decreased expression of erk1/erk2. We also found that complete inhibition via voltage gated K + channel blockade was associated with diminished phagocyte recruitment to the amputation site. The identification of H + pumps as required for axolotl tail regeneration supports findings in Xenopus and Planaria models, and more generally, the conservation of ion channels as regulators of tissue regeneration. This study provides a preliminary framework for an in-depth investigation of the mechanistic role of ion channels and their potential involvement in regulating cellular proliferation and other processes essential to wound healing, appendage regeneration, and tissue repair. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Effect of water quality on the feeding ecology of axolotl Ambystoma mexicanum

    Directory of Open Access Journals (Sweden)

    Diego de Jesus Chaparro-Herrera

    2013-10-01

    Full Text Available Ambystoma mexicanum, a highly endangered species, is endemic to lake Xochimilco (Mexico City, Mexico which currently is being negatively affected by the introduction of Oreochromis niloticus (Tilapia and water pollution. During the first weeks of development, when mortality is the highest, Ambystoma mexicanumdepends on a diet of zooplankton. The aim of this study was to check whether contamination levels in lake Xochimilco influence zooplankton consumption by similar size classes of A. mexicanum and Oreochromis niloticus. In this study, we analysed changes in the functional responses and prey preference of A. mexicanum and larval Tilapia in two media, one with filtered lake Xochimilco water and another one with reconstituted water. As prey we used cladocerans (Moina macrocopa, Alona glabra, Macrothrix triserialis and Simocephalus vetulus and ostracods (Heterocypris incongruens. Zooplankton was offered in 5 different densities, 10, 20, 40, 80, 160 ind./mL. Prey consumption by A. mexicanum varied in relation to the species offered and age of the larvae. From the first week to the eighth week prey consumption by A. mexicanum increased by 57%. Our functional response tests showed that regardless of the prey type, prey consumption by A. mexicanum was lower in the contaminated water from lake Xochimilco. Among the zooplankton offered in the contaminated environment predators preferred smaller and slower moving microcrustaceans such as Alona glabra and Heterocypris incongruens. Furthermore, O. niloticus preferred prey such as Moina macrocopa and Macrothrix triserialis in the contaminated medium and was more voracious than the axolotl. Our results indicate that both water quality of the lake and the presence of the more resistant exotic fish adversely impact the survival of this endangered amphibian.

  16. CNA proceedings

    International Nuclear Information System (INIS)

    1996-01-01

    The proceedings comprise keynote addresses, biographies, and 22 papers organized under the following headings: international CANDU operations, challenges in the uranium industry, public acceptance - gaining support, strategies for success in the nuclear business, nuclear power and the environment, initiatives in nuclear regulation, other opportunities. Individual papers published which come within the scope of INIS have been abstracted separately

  17. CNA proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    The proceedings comprise keynote addresses, biographies, and 22 papers organized under the following headings: international CANDU operations, challenges in the uranium industry, public acceptance - gaining support, strategies for success in the nuclear business, nuclear power and the environment, initiatives in nuclear regulation, other opportunities. Individual papers published which come within the scope of INIS have been abstracted separately.

  18. Mexican renewable electricity law

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz-Mendoza, B.J.; Sheinbaum-Pardo, C. [Institute of Engineering of the National Autonomous University of Mexico, Circuito Exterior s/n, Edificio 12 Bernardo Quintana, Piso 3, Cubiculo 319, Ciudad Universitaria, Delegacion Coyoacan, CP 04510, Mexico D.F. (Mexico)

    2010-03-15

    Two renewable electricity bills have been proposed in Congress since 2005 in Mexico. The first one was rejected by the Senate and the second one was approved by both the House of Representatives and the Senate in October 2008. Our objective is to explain the nature of both bills and to analyze each of them bearing in mind the Mexican electricity sector management scheme. In the Mexican electricity sector single-buyer scheme, the state-owned companies (Comision Federal de Electricidad and Luz y Fuerza del Centro) are responsible of the public services and the private sector generates electricity under six modalities: self-supply, cogeneration, independent production, small production, export, and import, which are not considered a public service. This scheme has caused controversies related to the constitutionality of the 1992 Power Public Services Law that allowed this scheme to be implemented. Both bills, the rejected one and the approved one, were formulated and based on that controversial law and their objectives are linked precisely more to the controversial issues than to the promotion of renewable electricity technologies; consequently, the gap among environmental, economic and social issues related with sustainability notion is wider. (author)

  19. Mexican renewable electricity law

    International Nuclear Information System (INIS)

    Ruiz-Mendoza, B.J.; Sheinbaum-Pardo, C.

    2010-01-01

    Two renewable electricity bills have been proposed in Congress since 2005 in Mexico. The first one was rejected by the Senate and the second one was approved by both the House of Representatives and the Senate in October 2008. Our objective is to explain the nature of both bills and to analyze each of them bearing in mind the Mexican electricity sector management scheme. In the Mexican electricity sector single-buyer scheme, the state-owned companies (Comision Federal de Electricidad and Luz y Fuerza del Centro) are responsible of the public services and the private sector generates electricity under six modalities: self-supply, cogeneration, independent production, small production, export, and import, which are not considered a public service. This scheme has caused controversies related to the constitutionality of the 1992 Power Public Services Law that allowed this scheme to be implemented. Both bills, the rejected one and the approved one, were formulated and based on that controversial law and their objectives are linked precisely more to the controversial issues than to the promotion of renewable electricity technologies; consequently, the gap among environmental, economic and social issues related with sustainability notion is wider. (author)

  20. Leucine-enkephalin-like immunoreactivity is localized in luteinizing hormone-producing cells in the axolotl (Ambystoma mexicanum) pituitary.

    Science.gov (United States)

    Suzuki, Hirohumi; Yamamoto, Toshiharu

    2014-02-01

    In this study, we used immunohistochemical techniques to determine the cell type of leucine-enkephalin (Leu-ENK)-immunoreactive cells in the axolotl (Ambystoma mexicanum) pituitary. Immunoreactive cells were scattered throughout the pars distalis except for the dorso-caudal portion. These cells were immuno-positive for luteinizing hormone (LH), but they were immuno-negative for adrenocorticotrophic, growth, and thyroid-stimulating hormones, as well as prolactin. Immunoelectron microscopy demonstrated that Leu-ENK-like substance and LH co-localized within the same secretory granules. Leu-ENK secreted from gonadotrophs may participate in LH secretion in an autocrine fashion, and/or may participate in the release of sex steroids together with LH. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. MEXICAN-AMERICAN STUDY PROJECT. ADVANCE REPORT 9, THE SPANISH AMERICANS OF NEW MEXICO--A DISTINCTIVE HERITAGE.

    Science.gov (United States)

    GONZALEZ, NANCIE L.

    USING NEW MEXICO AS A BASIS TO TRACE THE SPANISH-AMERICAN AND MEXICAN-AMERICAN HERITAGE, THE AUTHOR STATES THAT ANY STIGMA PLACED ON THE LATTER GROUP IS ONE OF CLASS DISTINCTION. THERE IS EVIDENCE THAT ACCULTURATION AND ASSIMILATION OF BOTH GROUPS INTO THE ANGLO-AMERICAN SOCIETY IS PROCEEDING STEADILY, AND THAT THE WORLD WARS AND THE KOREAN…

  2. Axolotl hemoglobin: cDNA-derived amino acid sequences of two alpha globins and a beta globin from an adult Ambystoma mexicanum.

    Science.gov (United States)

    Shishikura, Fumio; Takeuchi, Hiro-aki; Nagai, Takatoshi

    2005-11-01

    Erythrocytes of the adult axolotl, Ambystoma mexicanum, have multiple hemoglobins. We separated and purified two kinds of hemoglobin, termed major hemoglobin (Hb M) and minor hemoglobin (Hb m), from a five-year-old male by hydrophobic interaction column chromatography on Alkyl Superose. The hemoglobins have two distinct alpha type globin polypeptides (alphaM and alpham) and a common beta globin polypeptide, all of which were purified in FPLC on a reversed-phase column after S-pyridylethylation. The complete amino acid sequences of the three globin chains were determined separately using nucleotide sequencing with the assistance of protein sequencing. The mature globin molecules were composed of 141 amino acid residues for alphaM globin, 143 for alpham globin and 146 for beta globin. Comparing primary structures of the five kinds of axolotl globins, including two previously established alpha type globins from the same species, with other known globins of amphibians and representatives of other vertebrates, we constructed phylogenetic trees for amphibian hemoglobins and tetrapod hemoglobins. The molecular trees indicated that alphaM, alpham, beta and the previously known alpha major globin were adult types of globins and the other known alpha globin was a larval type. The existence of two to four more globins in the axolotl erythrocyte is predicted.

  3. El Arte Culinario Mexicano (Mexican Culinary Art).

    Science.gov (United States)

    Card, Michelle

    This unit in Mexican cooking can be used in Junior High School home economics classes to introduce students to Mexican culture or as a mini-course in Spanish at almost any level. It is divided into two parts. Part One provides historical background and information on basic foods, the Mexican market, shopping tips, regional cooking and customs.…

  4. Visualisation of axolotl blastema cells and pig endothelial progenitor cells using very small super paramagnetic iron oxide particles in MRI: A technique with applications for non invasive visualisation of regenerative processes

    DEFF Research Database (Denmark)

    Lauridsen, Henrik; Kjær, N.B.; Bek, Maria

    oxide particles (VSOP) in animal cells enable non invasive cell tracking using magnetic resonance imaging (MRI) and can prove useful, when visualising regenerative processes. This study examines the possibility of labelling limited numbers of axolotl blastema cells (aBC) and pig endothelial progenitor...... implanted in live axolotl tail and dead porcine heart, respectively. Cellular iron uptake was determined using inductively coupled plasma optical emission spectrometry (ICP-OES). Results: T2*-weighted 2D gradient-echo sequences on samples of 10˄5 cells yielded at significant linear correlations between...

  5. Conference Proceedings

    International Nuclear Information System (INIS)

    2002-01-01

    This volume contains the unedited proceedings of the Second Annual Conference on Managing Electricity Price Volatility. There were a total of eleven papers presented, dealing with a variety of issues affecting price volatility. Subjects treated included: new power generation development in Alberta; an analysis of electricity supply and demand to predict future price volatility; the effect of government intervention in the Alberta electricity market; risk management in volatile energy markets; an analysis of Alberta's capacity to supply its own internal electric power needs; the impact of increased electricity import and export capacity on price fluctuation in Alberta; improving market liquidity in Alberta; using weather derivatives to offset price risk; the impact of natural gas prices on electricity price volatility; capitalizing on advancements in online trading; and strategies for businesses to keep operating through times of price volatility. In most cases only overhead viewgraphs are available

  6. AIDS in Mexican prisons.

    Science.gov (United States)

    Olivero, J M; Roberts, J B

    1995-01-01

    The human rights organization Americas Watch, which toured Mexican prisons, reported in 1991 that all prisoners with HIV infection in the Mexico City area were housed in a single AIDS ward in Santa Marta Prison. In 1991, the 16-bed facility had 15 patients; in 1993, this number had increased by 5. In Mexico City, with 3 prisons holding over 2000 male adults each, there were only 20 known infected prisoners in the AIDS ward at Santa Marta. In 1991, authorities at Matamoros, in the state of Tamaulipas, insisted that none of their inmates had ever been diagnosed as infected with HIV. The prison physician at Reynosa indicated that only 2 inmates since 1985 had ever been diagnosed as infected. In 1992, the prison in Saltillo, in the state of Coahuila, reported that here had yet to be a single positive test for HIV. The prison at Reynosa held 1500 people and only 2 inmates were diagnosed as having AIDS between 1985 and 1991. Prisons at Matamoros and Saltillo held similar numbers but had no experience of infected inmates. A survey of 2 prisons in the state of Tamaulipas indicates that around 12% of the population may use IV drugs, and 9% indicate sharing needles. It is possible for prisoners to die of diseases like pneumonia, associated with AIDS, without the connection to AIDS being diagnosed. Each state, and possibly each prison in Mexico, has its own particular AIDS policies. Santa Marta was the single facility in Mexico City used to house AIDS-infected prisoners, who were segregated. Finally, the prison at Saltillo required all women entering the facility to have a medical examination, including a test for HIV. High-level prison personnel have demonstrated ignorance and fear of AIDS and intolerance of infected prisoners. Mexico must reassess the need to provide adequate medical care to offenders who are sick and dying behind bars.

  7. Mexican agencies reach teenagers.

    Science.gov (United States)

    Brito Lemus, R; Beamish, J

    1992-08-01

    The Gente Joven project of the Mexican Foundation for Family Planning (MEXFAM) trains young volunteers in 19 cities to spread messages about sexually transmitted diseases and population growth to their peers. They also distribute condoms and spermicides. It also uses films and materials to spread its messages. The project would like to influence young men's behavior, but the Latin image of machismo poses a big challenge. It would like to become more responsible toward pregnancy prevention. About 50% of adolescents have sexual intercourse, but few use contraceptives resulting in a high adolescent pregnancy rate. Many of these pregnant teenagers choose not to marry. Adolescent pregnancy leads to girls leaving school, few marketable skills, and rearing children alone. Besides women who began childbearing as a teenager have 1.5 times more children than other women. Male involvement in pregnancy prevention should improve these statistics. As late as 1973, the Health Code banned promotion and sales of contraceptives, but by 1992 about 50% of women of reproductive age use contraceptives. The Center for the Orientation of Adolescents has organized 8 Young Men's Clubs in Mexico City to involve male teenagers more in family planning and to develop self-confidence. It uses a holistic approach to their development through discussions with their peers. A MEXFAM study shows that young men are not close with their fathers who tend to exude a machismo attitude, thus the young men do not have a role model for responsible sexual behavior. MEXFAM's work is cut out for them, however, since the same study indicates that 50% of the young men believe it is fine to have 1 girlfriend and 33% think women should earn more than men. A teenager volunteer reports, however, that more boys have been coming to him for contraception and information than girls in 1992 while in other years girls outnumbered the boys.

  8. La Artesania Mexicana (Mexican Handicrafts).

    Science.gov (United States)

    Steele, Bettina

    This booklet contains instructions in English and Spanish for making eleven typical Mexican craft articles. The instructions are accompanied by pen-and-ink drawings. The objects are (1) "La Rosa" (The Rose); (2) "El Crisantemo" (The Chrysanthemum); (3) "La Amapola" (The Poppy); (4) "Ojos de Dios" (God's Eyes); (5) "Ojitos con dos caras" (Two-Sided…

  9. Historical aspects of Mexican psychiatry.

    Science.gov (United States)

    Bayardo, Sergio Javier Villaseñor

    2016-04-01

    Mexican psychiatry initiated since pre-Hispanic times. Historically, treatments were a mixture of magic, science and religion. Ancient Nahuas had their own medical concepts with a holistic view of medicine, considering men and cosmos as a whole. The first psychiatric hospital appeared in 1566 and a more modern psychiatric asylum emerged until 1910. International exchanges of theoretical approaches started in the National University with the visit of Pierre Janet. There were other important figures that influenced Mexican psychiatry, such as Erich Fromm, Henri Ey, Jean Garrabé and Yves Thoret. Regarding Mexican psychiatrists, some of the most important contributors to Mexican psychiatry were José Luis Patiño Rojas, Manuel Guevara Oropeza and Ramón de la Fuente Muñiz. This article includes excerpts from "Clinical Psychiatry", a book by Patiño Rojas where he tries to understand and describe the inner world experienced by patients with schizophrenia; also, the thesis conducted by Guevara Oropeza ("Psychoanalisis"), which is a critical comparison between the theories of Janet and Freud. Finally, we include "The study of consciousness: current status" by Ramón de la Fuente, which leads us through the initial investigations concerning consciousness, its evolution, and the contributions made by psychology, philosophy and neurobiology.

  10. Proverbs in Mexican American Tradition.

    Science.gov (United States)

    Arora, Shirley L.

    1982-01-01

    Examines proverb use among 304 Mexican Americans (aged 16-85) of Los Angeles (California), assembling information on how or where particular proverbs were learned, with whom or what kind of individual their use is associated, the occasions on which they are used, and general attitudes toward the use of proverbs. (LC)

  11. Regulation of Axolotl (Ambystoma mexicanum) Limb Blastema Cell Proliferation by Nerves and BMP2 in Organotypic Slice Culture.

    Science.gov (United States)

    Lehrberg, Jeffrey; Gardiner, David M

    2015-01-01

    We have modified and optimized the technique of organotypic slice culture in order to study the mechanisms regulating growth and pattern formation in regenerating axolotl limb blastemas. Blastema cells maintain many of the behaviors that are characteristic of blastemas in vivo when cultured as slices in vitro, including rates of proliferation that are comparable to what has been reported in vivo. Because the blastema slices can be cultured in basal medium without fetal bovine serum, it was possible to test the response of blastema cells to signaling molecules present in serum, as well as those produced by nerves. We also were able to investigate the response of blastema cells to experimentally regulated changes in BMP signaling. Blastema cells responded to all of these signals by increasing the rate of proliferation and the level of expression of the blastema marker gene, Prrx-1. The organotypic slice culture model provides the opportunity to identify and characterize the spatial and temporal co-regulation of pathways in order to induce and enhance a regenerative response.

  12. Regulation of Axolotl (Ambystoma mexicanum Limb Blastema Cell Proliferation by Nerves and BMP2 in Organotypic Slice Culture.

    Directory of Open Access Journals (Sweden)

    Jeffrey Lehrberg

    Full Text Available We have modified and optimized the technique of organotypic slice culture in order to study the mechanisms regulating growth and pattern formation in regenerating axolotl limb blastemas. Blastema cells maintain many of the behaviors that are characteristic of blastemas in vivo when cultured as slices in vitro, including rates of proliferation that are comparable to what has been reported in vivo. Because the blastema slices can be cultured in basal medium without fetal bovine serum, it was possible to test the response of blastema cells to signaling molecules present in serum, as well as those produced by nerves. We also were able to investigate the response of blastema cells to experimentally regulated changes in BMP signaling. Blastema cells responded to all of these signals by increasing the rate of proliferation and the level of expression of the blastema marker gene, Prrx-1. The organotypic slice culture model provides the opportunity to identify and characterize the spatial and temporal co-regulation of pathways in order to induce and enhance a regenerative response.

  13. Glucose transporter distribution in the vessels of the central nervous system of the axolotl Ambystoma mexicanum (Urodela: Ambystomatidae).

    Science.gov (United States)

    Lazzari, Maurizio; Bettini, Simone; Ciani, Franco; Franceschini, Valeria

    2008-10-01

    The GLUT-1 isoform of the glucose transporter is commonly considered a reliable molecular marker of blood-brain barrier endothelia in the neural vasculature organized in a three-dimensional network of single vessels. The central nervous system of the axolotl Ambystoma mexicanum is characterized by a vascular architecture that contains both single and paired vessels. The presence and distribution of the GLUT-1 transporter are studied in this urodele using both immunoperoxidase histochemistry and immunogold technique. Light microscopy reveals immunopositivity in both parenchymal and meningeal vessels. The transverse-sectioned pairs of vessels do not show the same size. Furthermore, in the same pair, the two elements often differ in diameter. The main regions of the central nervous system show a different percentage of the paired structures. Only immunogold cytochemistry reveals different staining intensity in the two adjoined elements of a vascular pair. Colloidal gold particles show an asymmetric distribution in the endothelia of both single and paired vessels. These particles are more numerous on the abluminal surface than on the luminal one. The particle density is calculated in both vascular types. The different values could indicate functional differences between single and paired vessels and between the two adjoined elements of a pair, regarding glucose transport.

  14. Crystal structure of axolotl (Ambystoma mexicanum) liver bile acid-binding protein bound to cholic and oleic acid.

    Science.gov (United States)

    Capaldi, Stefano; Guariento, Mara; Perduca, Massimiliano; Di Pietro, Santiago M; Santomé, José A; Monaco, Hugo L

    2006-07-01

    The family of the liver bile acid-binding proteins (L-BABPs), formerly called liver basic fatty acid-binding proteins (Lb-FABPs) shares fold and sequence similarity with the paralogous liver fatty acid-binding proteins (L-FABPs) but has a different stoichiometry and specificity of ligand binding. This article describes the first X-ray structure of a member of the L-BABP family, axolotl (Ambystoma mexicanum) L-BABP, bound to two different ligands: cholic and oleic acid. The protein binds one molecule of oleic acid in a position that is significantly different from that of either of the two molecules that bind to rat liver FABP. The stoichiometry of binding of cholate is of two ligands per protein molecule, as observed in chicken L-BABP. The cholate molecule that binds buried most deeply into the internal cavity overlaps well with the analogous bound to chicken L-BABP, whereas the second molecule, which interacts with the first only through hydrophobic contacts, is more external and exposed to the solvent. (c) 2006 Wiley-Liss, Inc.

  15. New tariffs confuse Mexican market

    International Nuclear Information System (INIS)

    Coeyman, M.

    1992-01-01

    Indelpro - the Grupo Alfa/Himont joint venture 150,000-m.t./year polypropylene (PP) plant in Altamira, Mexico - has been working to find its place in the Mexican market since coming onstream in March. At the same time, that market has been complicated by the imposition of import and export tariffs by the U.S. Department of Commerce early this fall. Commerce's accession to a 10% ad valorem tax on US PP exports to Mexico surprised some industry observers. The tariff is scheduled to be phased out within 10 years and is partly countermanded by a 5% tariff over a five-year period on Mexican PP exports to the US. But some market analysts say the arrangement is baffling

  16. NAFTA and the Mexican Economy

    Science.gov (United States)

    2008-11-04

    its loans. Then President Miguel de la Madrid took steps to open and liberalize the Mexican economy and initiated procedures to replace import...capita income in countries. 24 Lessons from NAFTA, 2005. 25 Economia , “NAFTA and Convergence in North America: High Expectations, Big Events, Little Time...Easterly, Norbert Fiess, and Daniel Lederman, Economia , “NAFTA and Convergence in North America: High Expectations, Big Events, Little Time,” Fall 2003. The

  17. INTRODUCING MEXICAN NEEDLETS FOR CMB ANALYSIS: ISSUES FOR PRACTICAL APPLICATIONS AND COMPARISON WITH STANDARD NEEDLETS

    International Nuclear Information System (INIS)

    Scodeller, S.; Rudjord, Oe.; Hansen, F. K.; Marinucci, D.; Geller, D.; Mayeli, A.

    2011-01-01

    Over the last few years, needlets have emerged as a useful tool for the analysis of cosmic microwave background (CMB) data. Our aim in this paper is first to introduce into the CMB literature a different form of needlets, known as Mexican needlets, first discussed in the mathematical literature by Geller and Mayeli. We then proceed with an extensive study of the properties of both standard and Mexican needlets; these properties depend on some parameters which can be tuned in order to optimize the performance for a given application. Our second aim in this paper is then to give practical advice on how to adjust these parameters for WMAP and Planck data in order to achieve the best properties for a given problem in CMB data analysis. In particular, we investigate localization properties in real and harmonic space and propose a recipe for quantifying the influence of galactic and point-source masks on the needlet coefficients. We also show that for certain parameter values, the Mexican needlets provide a close approximation to the Spherical Mexican Hat Wavelets (whence their name), with some advantages concerning their numerical implementation and derivation of their statistical properties.

  18. Corticotropin-releasing hormone-mediated metamorphosis in the neotenic axolotl Ambystoma mexicanum: synergistic involvement of thyroxine and corticoids on brain type II deiodinase.

    Science.gov (United States)

    Kühn, Eduard R; De Groef, Bert; Van der Geyten, Serge; Darras, Veerle M

    2005-08-01

    In the present study, morphological changes leading to complete metamorphosis have been induced in the neotenic axolotl Ambystoma mexicanum using a submetamorphic dose of T(4) together with an injection of corticotropin-releasing hormone (CRH). An injection of CRH alone is ineffective in this regard presumably due to a lack of thyrotropic stimulation. Using this low hormone profile for induction of metamorphosis, the deiodinating enzymes D2 and D3 known to be present in amphibians were measured in liver and brain 24h following an intraperitoneal injection. An injection of T(4) alone did not influence liver nor brain D2 and D3, but dexamethasone (DEX) or CRH alone or in combination with T(4) decreased liver D2 and D3. Brain D2 activity was slightly increased with a higher dose of DEX, though CRH did not have this effect. A profound synergistic effect occurred when T(4) and DEX or CRH were injected together, in the dose range leading to metamorphosis, increasing brain D2 activity more than fivefold. This synergistic effect was not found in the liver. It is concluded that brain T(3) availability may play an important role for the onset of metamorphosis in the neotenic axolotl.

  19. The Axolotl Fibula as a Model for the Induction of Regeneration across Large Segment Defects in Long Bones of the Extremities

    Science.gov (United States)

    Chen, Xiaoping; Song, Fengyu; Jhamb, Deepali; Li, Jiliang; Bottino, Marco C.; Palakal, Mathew J.; Stocum, David L.

    2015-01-01

    We tested the ability of the axolotl (Ambystoma mexicanum) fibula to regenerate across segment defects of different size in the absence of intervention or after implant of a unique 8-braid pig small intestine submucosa (SIS) scaffold, with or without incorporated growth factor combinations or tissue protein extract. Fractures and defects of 10% and 20% of the total limb length regenerated well without any intervention, but 40% and 50% defects failed to regenerate after either simple removal of bone or implanting SIS scaffold alone. By contrast, scaffold soaked in the growth factor combination BMP-4/HGF or in protein extract of intact limb tissue promoted partial or extensive induction of cartilage and bone across 50% segment defects in 30%-33% of cases. These results show that BMP-4/HGF and intact tissue protein extract can promote the events required to induce cartilage and bone formation across a segment defect larger than critical size and that the long bones of axolotl limbs are an inexpensive model to screen soluble factors and natural and synthetic scaffolds for their efficacy in stimulating this process. PMID:26098852

  20. CRISPR-Mediated Genomic Deletion of Sox2 in the Axolotl Shows a Requirement in Spinal Cord Neural Stem Cell Amplification during Tail Regeneration

    Directory of Open Access Journals (Sweden)

    Ji-Feng Fei

    2014-09-01

    Full Text Available The salamander is the only tetrapod that functionally regenerates all cell types of the limb and spinal cord (SC and thus represents an important regeneration model, but the lack of gene-knockout technology has limited molecular analysis. We compared transcriptional activator-like effector nucleases (TALENs and clustered regularly interspaced short palindromic repeats (CRISPRs in the knockout of three loci in the axolotl and find that CRISPRs show highly penetrant knockout with less toxic effects compared to TALENs. Deletion of Sox2 in up to 100% of cells yielded viable F0 larvae with normal SC organization and ependymoglial cell marker expression such as GFAP and ZO-1. However, upon tail amputation, neural stem cell proliferation was inhibited, resulting in spinal-cord-specific regeneration failure. In contrast, the mesodermal blastema formed normally. Sox3 expression during development, but not regeneration, most likely allowed embryonic survival and the regeneration-specific phenotype. This analysis represents the first tissue-specific regeneration phenotype from the genomic deletion of a gene in the axolotl.

  1. The Axolotl Fibula as a Model for the Induction of Regeneration across Large Segment Defects in Long Bones of the Extremities.

    Directory of Open Access Journals (Sweden)

    Xiaoping Chen

    Full Text Available We tested the ability of the axolotl (Ambystoma mexicanum fibula to regenerate across segment defects of different size in the absence of intervention or after implant of a unique 8-braid pig small intestine submucosa (SIS scaffold, with or without incorporated growth factor combinations or tissue protein extract. Fractures and defects of 10% and 20% of the total limb length regenerated well without any intervention, but 40% and 50% defects failed to regenerate after either simple removal of bone or implanting SIS scaffold alone. By contrast, scaffold soaked in the growth factor combination BMP-4/HGF or in protein extract of intact limb tissue promoted partial or extensive induction of cartilage and bone across 50% segment defects in 30%-33% of cases. These results show that BMP-4/HGF and intact tissue protein extract can promote the events required to induce cartilage and bone formation across a segment defect larger than critical size and that the long bones of axolotl limbs are an inexpensive model to screen soluble factors and natural and synthetic scaffolds for their efficacy in stimulating this process.

  2. The yeast two hybrid system in a screen for proteins interacting with axolotl (Ambystoma mexicanum) Msx1 during early limb regeneration.

    Science.gov (United States)

    Abuqarn, Mehtap; Allmeling, Christina; Amshoff, Inga; Menger, Bjoern; Nasser, Inas; Vogt, Peter M; Reimers, Kerstin

    2011-07-01

    Urodele amphibians are exceptional in their ability to regenerate complex body structures such as limbs. Limb regeneration depends on a process called dedifferentiation. Under an inductive wound epidermis terminally differentiated cells transform to pluripotent progenitor cells that coordinately proliferate and eventually redifferentiate to form the new appendage. Recent studies have developed molecular models integrating a set of genes that might have important functions in the control of regenerative cellular plasticity. Among them is Msx1, which induced dedifferentiation in mammalian myotubes in vitro. Herein, we screened for interaction partners of axolotl Msx1 using a yeast two hybrid system. A two hybrid cDNA library of 5-day-old wound epidermis and underlying tissue containing more than 2×10⁶ cDNAs was constructed and used in the screen. 34 resulting cDNA clones were isolated and sequenced. We then compared sequences of the isolated clones to annotated EST contigs of the Salamander EST database (BLASTn) to identify presumptive orthologs. We subsequently searched all no-hit clone sequences against non redundant NCBI sequence databases using BLASTx. It is the first time, that the yeast two hybrid system was adapted to the axolotl animal model and successfully used in a screen for proteins interacting with Msx1 in the context of amphibian limb regeneration. 2011 Elsevier B.V. All rights reserved.

  3. Transcriptome dynamics along axolotl regenerative development are consistent with an extensive reduction in gene expression heterogeneity in dedifferentiated cells

    Directory of Open Access Journals (Sweden)

    Carlos Díaz-Castillo

    2017-11-01

    Full Text Available Although in recent years the study of gene expression variation in the absence of genetic or environmental cues or gene expression heterogeneity has intensified considerably, many basic and applied biological fields still remain unaware of how useful the study of gene expression heterogeneity patterns might be for the characterization of biological systems and/or processes. Largely based on the modulator effect chromatin compaction has for gene expression heterogeneity and the extensive changes in chromatin compaction known to occur for specialized cells that are naturally or artificially induced to revert to less specialized states or dedifferentiate, I recently hypothesized that processes that concur with cell dedifferentiation would show an extensive reduction in gene expression heterogeneity. The confirmation of the existence of such trend could be of wide interest because of the biomedical and biotechnological relevance of cell dedifferentiation-based processes, i.e., regenerative development, cancer, human induced pluripotent stem cells, or plant somatic embryogenesis. Here, I report the first empirical evidence consistent with the existence of an extensive reduction in gene expression heterogeneity for processes that concur with cell dedifferentiation by analyzing transcriptome dynamics along forearm regenerative development in Ambystoma mexicanum or axolotl. Also, I briefly discuss on the utility of the study of gene expression heterogeneity dynamics might have for the characterization of cell dedifferentiation-based processes, and the engineering of tools that afforded better monitoring and modulating such processes. Finally, I reflect on how a transitional reduction in gene expression heterogeneity for dedifferentiated cells can promote a long-term increase in phenotypic heterogeneity following cell dedifferentiation with potential adverse effects for biomedical and biotechnological applications.

  4. Functional characterization of the vertebrate primary ureter: Structure and ion transport mechanisms of the pronephric duct in axolotl larvae (Amphibia

    Directory of Open Access Journals (Sweden)

    Prehn Lea R

    2010-05-01

    Full Text Available Abstract Background Three kidney systems appear during vertebrate development: the pronephroi, mesonephroi and metanephroi. The pronephric duct is the first or primary ureter of these kidney systems. Its role as a key player in the induction of nephrogenic mesenchyme is well established. Here we investigate whether the duct is involved in urine modification using larvae of the freshwater amphibian Ambystoma mexicanum (axolotl as model. Results We investigated structural as well as physiological properties of the pronephric duct. The key elements of our methodology were: using histology, light and transmission electron microscopy as well as confocal laser scanning microscopy on fixed tissue and applying the microperfusion technique on isolated pronephric ducts in combination with single cell microelectrode impalements. Our data show that the fully differentiated pronephric duct is composed of a single layered epithelium consisting of one cell type comparable to the principal cell of the renal collecting duct system. The cells are characterized by a prominent basolateral labyrinth and a relatively smooth apical surface with one central cilium. Cellular impalements demonstrate the presence of apical Na+ and K+ conductances, as well as a large K+ conductance in the basolateral cell membrane. Immunolabeling experiments indicate heavy expression of Na+/K+-ATPase in the basolateral labyrinth. Conclusions We propose that the pronephric duct is important for the subsequent modification of urine produced by the pronephros. Our results indicate that it reabsorbs sodium and secretes potassium via channels present in the apical cell membrane with the driving force for ion movement provided by the Na+/K+ pump. This is to our knowledge the first characterization of the pronephric duct, the precursor of the collecting duct system, which provides a model of cell structure and basic mechanisms for ion transport. Such information may be important in understanding

  5. Transcriptome dynamics along axolotl regenerative development are consistent with an extensive reduction in gene expression heterogeneity in dedifferentiated cells

    Science.gov (United States)

    2017-01-01

    Although in recent years the study of gene expression variation in the absence of genetic or environmental cues or gene expression heterogeneity has intensified considerably, many basic and applied biological fields still remain unaware of how useful the study of gene expression heterogeneity patterns might be for the characterization of biological systems and/or processes. Largely based on the modulator effect chromatin compaction has for gene expression heterogeneity and the extensive changes in chromatin compaction known to occur for specialized cells that are naturally or artificially induced to revert to less specialized states or dedifferentiate, I recently hypothesized that processes that concur with cell dedifferentiation would show an extensive reduction in gene expression heterogeneity. The confirmation of the existence of such trend could be of wide interest because of the biomedical and biotechnological relevance of cell dedifferentiation-based processes, i.e., regenerative development, cancer, human induced pluripotent stem cells, or plant somatic embryogenesis. Here, I report the first empirical evidence consistent with the existence of an extensive reduction in gene expression heterogeneity for processes that concur with cell dedifferentiation by analyzing transcriptome dynamics along forearm regenerative development in Ambystoma mexicanum or axolotl. Also, I briefly discuss on the utility of the study of gene expression heterogeneity dynamics might have for the characterization of cell dedifferentiation-based processes, and the engineering of tools that afforded better monitoring and modulating such processes. Finally, I reflect on how a transitional reduction in gene expression heterogeneity for dedifferentiated cells can promote a long-term increase in phenotypic heterogeneity following cell dedifferentiation with potential adverse effects for biomedical and biotechnological applications. PMID:29134148

  6. Transborder Library Forum [Proceedings] = Memorias del Foro Binacional de Bibliotecas (2nd, Hermosillo, Mexico, March 20-21, 1992).

    Science.gov (United States)

    1992

    At the second Transborder Library Forum, 181 participants from the United States and Mexico gathered to discuss topics of international librarianship. The proceedings include the following sections: Discurso de Bienvenida (Welcome Speech) (Carlos Salas); "El Etnocentrismo Mexicano y Los Servicios de Informacion" (Mexican Ethnocentrism…

  7. Business opportunities in the Mexican dairy industry

    NARCIS (Netherlands)

    Wijnands, J.H.M.; Armenta Gutierrez, B.M.; Poelarends, J.J.; Valk, van der O.M.C.

    2010-01-01

    This study explores the Mexican and Dutch business opportunities in the dairy industry in Mexico. The report discusses first the external environment of the Mexican dairy sector: the economic developments, the country's overall competitiveness, and the economic and agricultural policies. Next, it

  8. Stress Resilience among Border Mexican American Women

    Science.gov (United States)

    Guinn, Bobby; Vincent, Vern; Dugas, Donna

    2009-01-01

    The purpose of this study was to identify factors distinguishing Mexican American women living near the U.S.-Mexican border who are resilient to the experience of stress from those who are not. The study sample consisted of 418 participants ranging in age from 20 to 61 years. Data were gathered through a self-report survey instrument composed of…

  9. Mexican Women, Migration and Sex Roles.

    Science.gov (United States)

    Baca, Reynaldo; Dexter, Bryan

    1985-01-01

    Compares Mexican women involved in migration to understand how their sex roles and status have been affected. Uses data from two separate studies: ethnography on migrants' wives left at home in a Mexican village and a survey of unauthorized immigrants in the Los Angeles area. (SA)

  10. A Turnover Model for the Mexican Maquiladoras.

    Science.gov (United States)

    Maertz, Carl P.; Stevens, Michael J.; Campion, Michael A.

    2003-01-01

    From interviews with 47 Mexican maquiladora workers, a model of voluntary turnover was created and compared with models from the United States, Canada, England, and Australia. Despite similarities, the cultural and economic environment affected the precise content of antecedents in the Mexican model. (Contains 63 references.) (SK)

  11. Characterization of Mexican zeolite minerals

    International Nuclear Information System (INIS)

    Jimenez C, M.J.

    2005-01-01

    50% of the Mexican territory is formed by volcanic sequences of the Pliocene type, which appear extensively in the northwest states (Sonora, Sinaloa, Chihuahua, Durango) and west of Mexico (Jalisco and Nayarit), in central Mexico (Zacatecas, Guanajuato, San Luis Potosi, Queretaro, Hidalgo) and south of Mexico (Guerrero, Oaxaca); therefore, it is to be expected that in our country big locations of natural zeolites exist in its majority of the clinoptilolite type. The present study was focused toward the characterization of two Mexican natural zeolite rocks presumably of the clinoptilolite and filipsite types, one of them comes from the state of Chihuahua and the other of a trader company of non metallic minerals, due that these materials are not characterized, its are not known their properties completely and therefore, the uses that can be given to these materials. In this investigation work it was carried out the characterization of two Mexican zeolite rocks, one coming from the Arroyo zone, municipality of La Haciendita, in the state of Chihuahua; and the other one was bought to a trader company of non metallic minerals. The two zeolites so much in their natural form as conditioned with sodium; they were characterized by means of X-ray diffraction, scanning electron microscopy of high vacuum and elementary microanalysis (EDS), surface area analysis (BET), thermal gravimetric analysis. To differentiate the heulandite crystalline phase of the other clinoptilolite rock, its were carried out thermal treatments. The quantification of Al, Na, Ca, K, Mg, Fe was carried out in solution, by means of atomic absorption spectroscopy and the quantity of Si was determined by gravimetry. The zeolite rocks presented for the major part the crystalline heulandite and clinoptilolite phases for the most part, and it was found that the zeolite coming from the state of Chihuahua possesses a bigger content of heulandite and the denominated filipsite it is really a zeolite

  12. PREFACE: X Mexican School on Gravitation and Mathematical Physics: ''Reaching a Century: Classical and Modified General Relativity's Attempts to explain de evolution of the Universe''

    Science.gov (United States)

    Bárcenas, R. B.; Hernández, H. H. H.; Sabido, M.

    2015-11-01

    The collection of papers in this volume was presented during the X Mexican School on Gravitation and Mathematical Physics, which was held in Playa del Carmen, Quintana Roo, México, December 1-5, 2014. The Mexican School on Gravitation and Mathematical Physics is a series of conferences sponsored by the Mexican Physical Society that started in 1994 with the purposes of discussing and exchanging current ideas in gravitational physics. Each Mexican School has been devoted to a particular subject, and these have included supergravity, branes, black holes, the early Universe, observational cosmology, quantum gravity and numerical relativity. In this ocasion the theme of the school was Reaching a Century: Classical and Modified General Relativity's Attempts to explain the evolution of the Universe, which focused on the discussion of classical and modified aspects of general relativity. Following our previous Schools, world leaders in the field were invited to give courses and plenary lectures. More specialized talks were also presented in parallel sessions, and some of them have been included in these proceedings. The contributions in this volume have been reviewed and represent some of the courses, plenary talks and contributed talks presented during our X School. We are indebted to the contributors of these proceedings as well as to the rest of the participants in our Mexican School all for making of it a complete success. As for financial support we should mention the Mexican National Science and Technology Council (CONACyT), the Royal Society of London (UK), the Mexican Physical Society (SMF), as well as several Institutions including: Centro de Investigación y Estudios Avanzados (CINVESTAV), Universidad Autónoma Metropolitana Iztapalapa (UAM-I), Universidad de Guanajuato (UG), and Universidad Nacional Autónoma de México (UNAM).

  13. Oxygen consumption and cytochrome exidase activity of axolotl limbs muscle tissue in restoration of regenerative ability suprressed by X-irradiation

    International Nuclear Information System (INIS)

    Teplits, N.A.

    1975-01-01

    The rate of oxygen use and activity of cytochrome oxidase in a homogenate of mitochondria and nuclei of muscle tissue of axolotl limbs after suppression of their regenerative capability by x irradiation and their restoration was studied experimentally. With suppression of the regenative capability the use of oxygen was depressed. Cytochrome oxidase activity in the homogenate and mitochondria decreased compared to that of the intact limb, in the nuclei of muscle tissue it was the same or greater. With restoration of the regenerative capability of the limbs the respiration rate of the homogenate and the mitochondria increased, accompanied by increased cytochrome oxidase activity. In the nuclei the cytochrome oxidase activity did not change in the blastema stage and sharply decreased in the limb formation state. (E.T.)

  14. Oxygen consumption and cytochrome exidase activity of axolotl limbs muscle tissue in restoration of regenerative ability suppressed by X-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Teplits, N A [AN SSSR, Moscow. Inst. Biologii Razvitiya

    1975-01-01

    The rate of oxygen use and activity of cytochrome oxidase in a homogenate of mitochondria and nuclei of muscle tissue of axolotl limbs after suppression of their regenerative capability by x irradiation and their restoration was studied experimentally. With suppression of the regenative capability the use of oxygen was depressed. Cytochrome oxidase activity in the homogenate and mitochondria decreased compared to that of the intact limb, in the nuclei of muscle tissue it was the same or greater. With restoration of the regenerative capability of the limbs the respiration rate of the homogenate and the mitochondria increased, accompanied by increased cytochrome oxidase activity. In the nuclei the cytochrome oxidase activity did not change in the blastema stage and sharply decreased in the limb formation state.

  15. Ontogeny of the VIP system in the gastro-intestinal tract of the Axolotl, Ambystoma mexicanum: successive appearance of co-existing PACAP and NOS.

    Science.gov (United States)

    Badawy, Gamal; Reinecke, Manfred

    2003-03-01

    Evidence for the presence and potential co-existence of vasoactive intestinal polypeptide (VIP), pituitary adenylate cyclase-activating polypeptide (PACAP) and nitric oxide synthase (NOS) in gastro-intestinal endocrine cells and/or nerve fibers is conflicting and very few results exist on development. This immunofluorescence study aims to clarify the appearance and localization of VIP, PACAP and NOS in the gastro-intestinal tract of the Axolotl, Ambystoma mexicanum, during ontogeny. VIP-immunoreactivity appeared in nerve fibers as early as on day 3 after hatching likely indicating a particular role, such as a trophic action, of VIP in very early development. PACAP-immunoreactivity was observed 3 days later within the VIP-immunoreactive (-IR) fibers. From this time on, VIP- and PACAP-immunoreactivity exhibited complete co-existence. VIP/PACAP-IR fibers were found throughout the gastro-intestinal tract. They were most prominent in the myenteric plexus and the muscle layers and less frequent in the submucosa. NOS-immunoreactivity appeared as late as at the 1st (64 days) juvenile stage in a subpopulation of the VIP/PACAP-IR fibers that contacted submucosal arteries. We found only very few VIP/PACAP-IR perikarya, indicating that part of the VIP/PACAP-IR fibers is of extrinsic origin. On day 12 and in the 1st and 2nd (104 days) juvenile stage, infrequent PACAP-IR entero-endocrine cells were noted, while neither VIP- nor NOS-immunoreactivity occurred in endocrine cells at any stage of development. The complete coexistence of neuronal PACAP- and VIP-immunoreactivities and their very early appearance in ontogeny may suggest important and coordinated roles of both peptides in the control of Axolotl gastro-intestinal activity, while the VIP/ PACAP/NOS-IR fibers may be involved in the regulation of submucosal blood flow.

  16. Mexican participation in the AMS project

    Science.gov (United States)

    Menchaca-Rocha, A.; Buenerd, M.; Cabrera, J. I.; Canizal, C.; Esquivel, O.; Núñez, R.; Plascencia, J. C.; Reyes, T.; Villoro, M. F.

    2001-05-01

    Optical characterization of hydrophobic silica aerogel SP-25 for the RICH, and a scheme to generate particle-ID conditions on TOF and Tracker amplitude data are reported, as part of a Mexican effort to contribute to the AMS Project. .

  17. Mammagraphy Use by Older Mexican American Women

    National Research Council Canada - National Science Library

    Freeman, Jean

    1998-01-01

    The purpose of this study is to examine the determinants of mammographic screening in older Mexican- American women, particularly the influence of strong family relationships on promoting screening behavior...

  18. NAFTA: The Mexican Economy, and Undocumented Migration

    Science.gov (United States)

    2011-10-28

    NAFTA contributed to modest increases in Mexican formal employment since 1994. Since employment constitutes one of the chief factors affecting poverty...any other provision of law , no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a...FINAL 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE NAFTA , the Mexican Economy, and Undocumented Migration 5a

  19. Generational Variations in Mexican-Origin Intermarriage

    OpenAIRE

    Cedillo, Rosalio

    2015-01-01

    This dissertation examines intermarriage across generations of the Mexican-origin population in order to better understand how this population is incorporating in U.S. society, and looks at parental migration status and parental nativity as factors that may impede or facilitate intermarriage incorporation. Using data from the Immigration and Intergenerational Mobility in Metropolitan Los Angeles (IIMMLA) survey the research shows that: the majority of intermarriages among the Mexican-origin ...

  20. Proceedings of the 7 Annual conference of the Mexican association for the energy economy. The energy sector in Mexico: challenges and solutions. [Selected papers]; 7. Conferencia anual de la asociacion mexicana para la economia energetica. El sector energia en Mexico: retos y soluciones

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    The Mexican Association for the Energy Economy (AMEE) had its VII annual conference, The energy sector in Mexico: challenges and solutions, in October, 2004. Some of the expounded topics are: technical and environmental aspects of the combined cycle power stations; analysis of the generation of electric power across biogas from sanitary landfills in Mexico; cogeneration in large power plants; methodologies for the calculation of relative efficiency: description and application of natural gas distributors in Latin American and others. [Spanish] La Asociacion Mexicana para la Economia Energetica A. C. (AMEE), llevo acabo su VII conferencia anual El sector energia en Mexico: retos y soluciones, en octubre del 2004. Algunos de los temas tratados son: Aspectos tecnicos y medioambientales de las centrales de ciclo combinado con gasificacion integrada; Analisis de la generacion de energia electrica a traves de biogas procedente de rellenos sanitarios en Mexico; Cogeneracion en grandes centrales de proceso; Metodologias para el calculo de eficiencia relativa: descripcion y aplicacion para distribuidores de gas natural en Latinoamerica y otros.

  1. Locomotion of Mexican jumping beans

    International Nuclear Information System (INIS)

    West, Daniel M; K Lal, Ishan; Leamy, Michael J; Hu, David L

    2012-01-01

    The Mexican jumping bean, Laspeyresia saltitans, consists of a hollow seed housing a moth larva. Heating by the sun induces movements by the larva which appear as rolls, jumps and flips by the bean. In this combined experimental, numerical and robotic study, we investigate this unique means of rolling locomotion. Time-lapse videography is used to record bean trajectories across a series of terrain types, including one-dimensional channels and planar surfaces of varying inclination. We find that the shell encumbers the larva's locomotion, decreasing its speed on flat surfaces by threefold. We also observe that the two-dimensional search algorithm of the bean resembles the run-and-tumble search of bacteria. We test this search algorithm using both an agent-based simulation and a wheeled Scribbler robot. The algorithm succeeds in propelling the robot away from regions of high temperature and may have application in biomimetic micro-scale navigation systems. (paper)

  2. Mexican gems as thermoluminescent dosimeters

    International Nuclear Information System (INIS)

    Azorin N, J.

    1979-01-01

    The possibility of using naturally ocurring mexican gems as thermoluminescent dosimeters (TLD) was investigated. Twelve types of gems were irradiated with X and gamma rays in order to determinate their dosimetric properties. Three of these gems showed favorable thermoluminescent characteristics compared with commercial thermoluminescent dosimeters. The plots of their thermoluminescent response as a function of gamma dose are straight lines on full log paper in the dose range 10 -2 to 10 2 Gy. The energy dependence is very strong to low energies of the radiation. Their fading was found to be about 5%/yr. and they may be annealed as reused without loss in sensitivity. Therefore, these gems can be used as X and gamma radiation dosimeters. (author)

  3. Fair Start Program: Outreach to Mexican and Mexican American Farmworker Families.

    Science.gov (United States)

    Winters-Smith, Carol; Larner, Mary

    This presentation describes a home visiting health education program serving Mexican and Mexican-American migrant farmworkers in Florida. The purposes of the program were to educate farmworker families about pregnancy, childbirth, nutrition, and child development, and to encourage the use of preventive health care services. Home visitors were…

  4. PREFACE: X Workshop of the Gravitation and Mathematical Physics Division, Mexican Physical Society

    Science.gov (United States)

    2014-11-01

    The collection of papers in this volume was presented during the X Workshop of the Gravitation and Mathematical Physics Division of the Mexican Physical Society (DGFM-SMF), which was held in Pachuca, Hidalgo, México, December 2-6, 2013. The Workshop is a bi-annual series of conferences sponsored by the DGFM-SMF that started in 1993 with the purposes of discussing and exchanging the research and experience of the gravitational and mathematical physics communities in Mexico. Each Mexican Workshop has been devoted to subjects of broad interest, so that students, in particular, can have access to specialized courses and talks that allow them to raise up their qualifications as professional researchers. Recurrent topics in the Mexican Workshop are supergravity, branes, black holes, the early Universe, observational cosmology, quantum gravity and cosmology and numerical relativity. Following our previous Workshops, distinguished researchers in the field, working in Mexico, were invited to give courses, whereas young researchers were invited for plenary lectures. More specialized talks were also presented in parallel sessions, with ample participation of researchers, and graduate and undergraduate students; most of the presentations have been included in these proceedings. The contributions in this volume have been peer-reviewed, and they represent most of the courses, plenary talks and contributed talks presented during our Workshop. We are indebted to the contributors of these proceedings, as well as to the other participants and organizers, all for making the event a complete success. We acknowledge the professionalism of our reviewers, who helped us to keep high quality standards in all manuscripts. Acknowledgments The organizing committee would like to acknowledge the financial support of the Mexican National Science and Technology Council (CONACyT), the Mexican Physical Society (SMF), as well as several Institutions including: Centro de Investigación y Estudios

  5. Two Decades of Mexican Particle Physics at Fermilab

    International Nuclear Information System (INIS)

    Rubinstein, R.

    2003-01-01

    This report is a view from Fermilab of Mexican particle physics at the Laboratory since about 1980; it is not intended to be a history of Mexican particle physics: that topic is outside the expertise of the writer. The period 1980 to the present coincides with the growth of Mexican experimental particle physics from essentially no activity to its current state where Mexican groups take part in experiments at several of the world's major laboratories

  6. IPHE Infrastructure Workshop Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    None

    2010-02-01

    This proceedings contains information from the IPHE Infrastructure Workshop, a two-day interactive workshop held on February 25-26, 2010, to explore the market implementation needs for hydrogen fueling station development.

  7. Radiofrequency plasma heating: proceedings

    International Nuclear Information System (INIS)

    Swenson, D.G.

    1985-01-01

    The conference proceedings include sessions on Alfven Wave Heating, ICRF Heating and Current Drive, Lower Hybrid Heating and Current Drive, and ECRF Heating. Questions of confinement, diagnostics, instabilities and technology are considered. Individual papers are cataloged separately

  8. Proceedings of oceans '91

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    This volume contains the proceedings of the Oceans '91 Conference. Topics addressed include: ocean energy conversion, marine communications and navigation, ocean wave energy conversion, environmental modeling, global climate change, ocean minerals technology, oil spill technology, and submersible vehicles

  9. Green Medicine: Traditional Mexican-American Herbal Remedies.

    Science.gov (United States)

    Torres, Eliseo

    Traditional Mexican American herbal potions and remedies and their history are explained in an introductory book for the general reader. The importance of curanderismo, or green medicine, in Mexican and Mexican American cultures is explored. A brief history traces the herbal aspects of curanderismo through Mayan and Aztec cultures, the Spanish…

  10. Los Dos Mundos: Rural Mexican Americans, Another America.

    Science.gov (United States)

    Baker, Richard

    This book explores race relations between Mexican Americans and Anglo Americans in "Middlewest," a fictitious name for an actual rural Idaho community with the highest proportion of Mexican Americans in the state. Many Mexican Americans in this predominantly agricultural area are current or former migrant workers. The first chapter…

  11. Mexican energy policy and sustainability indicators

    International Nuclear Information System (INIS)

    Sheinbaum-Pardo, Claudia; Ruiz-Mendoza, Belizza Janet; Rodríguez-Padilla, Víctor

    2012-01-01

    The authors analyze the Mexican energy policy taking as reference the methodological framework for sustainable energy development proposed by the Economic Commission for Latin America and the Caribbean. This methodology takes eight related indicators to the social, environmental and economic dimensions in order to calculate a general sustainability indicator for the energy sector. In this methodology, the weight of each dimension is different; namely, the social and environmental issues have less relevance than the economic issues. The authors use this methodology because government institutions as the Department of Energy and the Department of Environment and Natural Resources have used some indicators from such a methodology to propose plans, programs, projects and bills. Authors know of the existence of other methodologies about sustainability. Nonetheless, opting for the Economic Commission for Latin America and the Caribbean's methodology is convenient because this organization is a respectable authority for civil servants from the Mexican institutions. Our objective is just to contrast the sustainability grade of the energy sector between 1990 and 2008 for Mexico whose government started reforms in the 1990s. It concludes that those reforms did not bring about a higher sustainability level for the energy sector. - Highlights: ► We used the OLADE, CEPAL and GTZ's methodology to calculate sustainability indicators for the Mexican energy sector. ► We studied the Mexican energy policy from 1990 to date and presented it. ► Currently, the Mexican energy sector is less sustainable than in 1990.

  12. PREFACE: XIV Mexican Workshop on Particles and Fields

    Science.gov (United States)

    Delepine, D.; Napsuciale, M.; Ibarguen, H. S.

    2015-11-01

    The Mexican Workshop on Particles and Fields (MWPF) is a biennial meeting organized by the Division of Particles and Fields of the Mexican Physical Society designed to gather specialists in different areas of high energy physics to discuss the latest developments in the field. The fourteenth edition of this meeting was held from November 25 to 29, 2013, at the colonial city of Oaxaca de Juárez, Oaxaca, Mexico. The XIV Mexican Workshop on Particles and Fields consisted of invited lectures, discussion and poster sessions. Experimental and theoretical developments were presented by distinguished physicists, addressing the most recent results in the field. The invited review talks included topics on collider physics, neutrino physics, physics beyond the Standard Model, flavor and hadronic physics, astroparticle physics, dark matter physics and effective theories, among others. The highlight topic of the conference was the presentation of the most resent results from the most popular high energy experiments in the world. The discovery of a particle consistent with the long-sought Higgs boson, considered one of the most important discoveries of the 21st century, was fully addressed by José Benítez and Kirill Prokofiev from CERN. The overview of the results of ALICE on the first run of the LHC was extensivly covered by Antonio Ortiz, from Lund University, and Daniel Tapia, from Universití Paris-Sud. The prospects and status of the new Belle II experiment were presented by Yoshi Sakai from KEK. The plans and projects of Tevatron on the new era of accelerators were explained by Gene Fisk from FERMILAB. Eric Vázquez from SNOLAB presented a wonderful explanation about the Dark Matter detection and the most resent results about the searches for it. The largest high energy cosmic rays detector, the Pierre Auger, was presented by Luis Villasñnor from University of Michoacán. On Friday 29th of November, we had an excursion to the archeological site of Mitla and to Santa

  13. Craniofacial Secular Change in Recent Mexican Migrants.

    Science.gov (United States)

    Spradley, Katherine; Stull, Kyra E; Hefner, Joseph T

    2016-01-01

    Research by economists suggests that recent Mexican migrants are better educated and have higher socioeconomic status (SES) than previous migrants. Because factors associated with higher SES and improved education can lead to positive secular changes in overall body form, secular changes in the craniofacial complex were analyzed within a recent migrant group from Mexico. The Mexican group represents individuals in the act of migration, not yet influenced by the American environment, and thus can serve as a starting point for future studies of secular change in this population group. The excavation of a historic Hispanic cemetery in Tucson, Arizona, also allows for a comparison between historic Hispanics and recent migrants to explore craniofacial trends over a broad time period, as both groups originate from Mexico. The present research addresses two main questions: (1) Are cranial secular changes evident in recent Mexican migrants? (2) Are historic Hispanics and recent Mexican migrants similar? By studying secular changes within a migrant population group, secular trends may be detected, which will be important for understanding the biological variation of the migrants themselves and will serve as a preliminary investigation of secular change within Mexican migrants. The comparison of a sample of recent Mexican migrants with a historic Hispanic sample, predominantly of Mexican origin, allows us to explore morphological similarities and differences between early and recent Mexicans within the United States. Vault and face size and a total of 82 craniofacial interlandmark distances were used to explore secular changes within the recent Mexican migrants (females, n = 38; males, n = 178) and to explore the morphological similarities between historic Hispanics (females, n = 54; males, n = 58) and recent migrants. Sexes were separated, and multivariate adaptive regression splines and basis splines (quadratic with one knot) were used to assess the direction and magnitude

  14. Nervios and dysphoria in Mexican American widows.

    Science.gov (United States)

    Kay, M; Portillo, C

    1989-01-01

    One hundred widows participating in experimental research entitled Efficacy of Support Groups for Mexican American Widows were studied to learn how they express the loss of their husbands. Mourning practices, acknowledged symptoms of dysphoria, and somatic reactions were studied to learn if the syndrome of nervios subsumes their reaction to bereavement. In addition, their responses to instruments designed to measure depression, the Spanish version of the Beck Depression Inventory and the Center for Epidemiologic Studies Depression Scale, were examined for correlation with nervios and relationships to Mexican American acculturation. Nervios seems to be a manifestation of dysphoria rather than a specific syndrome for these women.

  15. Mexican oil industry: Shifting to difficult oil

    Energy Technology Data Exchange (ETDEWEB)

    Bazan G., Gerardo; Gonzalez, Cristobal J.

    2010-09-15

    Mexico has stepped into an important transition of declining oil fields and new challenging oil projects. The aim of this paper is to show a new perspective of the oil resources that have been exploited throughout the Mexican territory, as well as the remaining resources yet to be exploited. We have developed a resources/production-costs chart that illustrates the historical and future development of the Mexican oil industry, showing the shift that the industry will face in the coming years; this chart was taken from a model already in use by the most prestige energy agencies in the world.

  16. Invisible Infantry: Mexicans in World War II

    Directory of Open Access Journals (Sweden)

    Enrique Plasencia de la Parra

    2003-04-01

    Full Text Available This paper analyses the  participation of Mexican  and  Mexican- American troops in the United States army during World War II. Recruiting, discrimination, their  role  in the  armed forces  and their reinsertion into society once the war ended, are examined. Special emphasis is placed  on the  Hispanics  fight for their  civil and political rights that was carried on very actively by many War veterans.

  17. Employers mexican migrants in the United States

    Directory of Open Access Journals (Sweden)

    Eduardo Fernández Guzmán

    2013-09-01

    Full Text Available You might think that by definition the migrant labor plays in less profitable niches and meager social mobility. However, a large group of migrants in different economically developed countries have successfully launched businesses of diverse nature and volume. This is why entrepreneurship of migrants is an issue that has received increasing attention in recent years. Compared to other immigrant groups in the United States, Mexicans show low levels of entrepreneurial activity. The aim of this paper is to, through a general literature review of official statistical data, a preliminary analysis of mexican migrant entrepreneurship in the United States, that is to say in recent years has been growing in importance.

  18. The Smell of Memories. A Mexican Migrant’s Search for Emotional Sustainability through Mexican Films.

    OpenAIRE

    Gabriela Coronado

    2011-01-01

    For more than 10 years living as a Mexican migrant, between two countries (Mexico and Australia), two cities (Mexico City and Sydney), and two social worlds (Mexican and multicultural Australian ‘families-friends’), I have been immersed in a systematic process of self observation and self reflection on my life in my country of destination. During this time I have explored my memories of place and their relationship with my emotional experiences, looking for strategies to continue to be connec...

  19. Subjective Social Status, Mental and Psychosocial Health, and Birth Weight Differences in Mexican-American and Mexican Immigrant Women.

    Science.gov (United States)

    Fleuriet, K Jill; Sunil, T S

    2015-12-01

    Recent Mexican immigrant women on average have an unexpectedly low incidence of low birth weight (LBW). Birth weights decline and LBW incidence increases in post-immigrant generations. This pilot project tested the hypothesis that subjective social status (SSS) of pregnant women predicts variation in birth weight between Mexican immigrant and Mexican-American women. 300 low-income pregnant Mexican immigrant and Mexican-American women in South Texas were surveyed for SSS, depression, pregnancy-related anxiety, perceived social stress and self-esteem and subsequent birth weight. No significant difference in SSS levels between pregnant Mexican immigrant and Mexican-American women were found. However, SSS better predicted variation in birth weight across both groups than mental and psychosocial health variables. Results suggest distinct relationships among SSS, mental and psychosocial health that could impact birth weight. They underscore the relevance of a multilevel, biopsychosocial analytical framework to studying LBW.

  20. Analysis of the expression and function of Wnt-5a and Wnt-5b in developing and regenerating axolotl (Ambystoma mexicanum) limbs.

    Science.gov (United States)

    Ghosh, Sukla; Roy, Stéphane; Séguin, Carl; Bryant, Susan V; Gardiner, David M

    2008-05-01

    Urodele amphibians are unique adult vertebrates because they are able to regenerate body parts after amputation. Studies of urodele limb regeneration, the key model system for vertebrate regeneration, have led to an understanding of the origin of blastema cells and the importance of positional interactions between blastema cells in the control of growth and pattern formation. Progress is now being made in the identification of the signaling pathways that regulate dedifferentiation, blastema morphogenesis, growth and pattern formation. Members of the Wnt family of secreted proteins are expressed in developing and regenerating limbs, and have the potential to control growth, pattern formation and differentiation. We have studied the expression of two non-canonical Wnt genes, Wnt-5a and Wnt-5b. We report that they are expressed in equivalent patterns during limb development and limb regeneration in the axolotl (Ambystoma mexicanum), and during limb development in other tetrapods, implying conservation of function. Our analysis of the effects of ectopic Wnt-5a expression is consistent with the hypothesis that canonical Wnt signaling functions during the early stages of regeneration to control the dedifferentiation of stump cells giving rise to the regeneration-competent cells of the blastema.

  1. Mexican-Americans in the Southwest.

    Science.gov (United States)

    Galarza, Ernesto; And Others

    With findings as presented in this 1969 book, a 2-year field study conducted by a 3-member team analyzed the economic, cultural, political, and educational conditions of Mexican Americans in the Southwest (California, Arizona, New Mexico, Colorado, and Texas) with some reference to braceros and the situation in Mexico. An overview of 8 geographic…

  2. Barreda, Vasconcelos, and Mexican Educational Reforms.

    Science.gov (United States)

    Skirius, John

    1983-01-01

    Reviews the contributions to Mexican education of Gabino Barredas' positivism between 1867-1898 and the contributions of Jose Vasconcelos during the 1920s. Discusses the secondary curriculum reforms of Barreda's era and the vocational education and the education for women and adults during the Vasconcelos era. (SB)

  3. Weight Preoccupation in Female Mexican American Adolescents.

    Science.gov (United States)

    Guinn, Bobby; Jorgensen, Layne; Semper, Tom; Vincent, Vern

    2002-01-01

    Investigated the contribution of body size, self-esteem, age, mainstream acculturation, and athletic status to concern or preoccupation about weight among female Mexican American adolescents. Students had low acculturation, high body fatness, and moderate self-esteem. There was little difference between athletes and non-athletes. Greater body size…

  4. New offshore platform in the Mexican Gulf

    Energy Technology Data Exchange (ETDEWEB)

    Beisel, T.

    1982-04-01

    After a construction period of only 10 months, the second steel Offshore platform was recently completed in the Mexican Gulf. The pattern for this structure was the Cognac platform. The erection of the new platform, called the 'Cerveza' platform, is described in the article.

  5. Conflict Resolution between Mexican Origin Adolescent Siblings

    Science.gov (United States)

    Killoren, Sarah E.; Thayer, Shawna M.; Updegraff, Kimberly A.

    2008-01-01

    We investigated correlates of adolescents' sibling conflict resolution strategies in 246, two-parent Mexican origin families. Specifically, we examined links between siblings' conflict resolution strategies and sibling dyad characteristics, siblings' cultural orientations and values, and sibling relationship qualities. Data were gathered during…

  6. The Mexican American Woman and Mental Health.

    Science.gov (United States)

    Gibson, Guadalupe

    For a long time Chicanas have been self-denying, self sacrificing. Well, it is time that Mexican American women began thinking of themselves. It follows that if women love and cherish others, they must begin by loving and cherishing themselves. From the mental health perspective it is essential that they do so, not only for their sake, but for…

  7. Civic Engagement Patterns of Undocumented Mexican Students

    Science.gov (United States)

    Perez, William; Espinoza, Roberta; Ramos, Karina; Coronado, Heidi; Cortes, Richard

    2010-01-01

    This study examined the civic engagement of undocumented Mexican students. Civic engagement was defined as providing a social service, activism, tutoring, and functionary work. Survey data results (n = 126) suggest that despite high feelings of rejection because of their undocumented status, part-time employment, and household responsibilities,…

  8. Open Access to Mexican Academic Production

    Science.gov (United States)

    Adame, Silvia I.; Llorens, Luis

    2016-01-01

    This paper presents a description of the metadata harvester software development. This system provides access to reliable and quality educational resources, shared by Mexican Universities through their repositories, to anyone with Internet Access. We present the conceptual and contextual framework, followed by the technical basis, the results and…

  9. The Mexican-American and Dramatic Literature.

    Science.gov (United States)

    Serrano, Hector M.

    In the area of the arts, the Mexican American has discovered a rich cultural heritage which gives him a strong sense of pride and a deep feeling of satisfaction. A new interest in the literature of Mexico and the Southwestern states of Texas, Arizona, New Mexico, Colorado, and California has started the Chicano people reading classic and modern…

  10. Decision Profiles of Mexican-Descent Families.

    Science.gov (United States)

    Baker, Georgianne

    An exploratory study of decision-making in families of Mexican heritage was carried out in Phoenix, Arizona. A Normative model of decision rationality and measurement (Family Problem Instrument-FPI) was adapted from previous research. Tape-recorded data were provided by 27 families. Husbands and wives responded separately to family decision…

  11. Conference proceedings ISES 2014

    DEFF Research Database (Denmark)

    Christensen, Janne Winther; Peerstrup Ahrendt, Line; Malmkvist, Jens

    The 10th Internatinal Equitation Science Conference is held i Denmark from August 6th - 9th 2014. This book of proceedings contaions abstracts of 35 oral and 57 poster presentations within the conference themes Equine Stress, Learning and Training as well as free papers.......The 10th Internatinal Equitation Science Conference is held i Denmark from August 6th - 9th 2014. This book of proceedings contaions abstracts of 35 oral and 57 poster presentations within the conference themes Equine Stress, Learning and Training as well as free papers....

  12. Racial Identity and Racial Treatment of Mexican Americans.

    Science.gov (United States)

    Ortiz, Vilma; Telles, Edward

    2012-04-01

    How racial barriers play in the experiences of Mexican Americans has been hotly debated. Some consider Mexican Americans similar to European Americans of a century ago that arrived in the United States with modest backgrounds but were eventually able to participate fully in society. In contrast, others argue that Mexican Americans have been racialized throughout U.S. history and this limits their participation in society. The evidence of persistent educational disadvantages across generations and frequent reports of discrimination and stereotyping support the racialization argument. In this paper, we explore the ways in which race plays a role in the lives of Mexican Americans by examining how education, racial characteristics, social interactions, relate to racial outcomes. We use the Mexican American Study Project, a unique data set based on a 1965 survey of Mexican Americans in Los Angeles and San Antonio combined with surveys of the same respondents and their adult children in 2000, thereby creating a longitudinal and intergenerational data set. First, we found that darker Mexican Americans, therefore appearing more stereotypically Mexican, report more experiences of discrimination. Second, darker men report much more discrimination than lighter men and than women overall. Third, more educated Mexican Americans experience more stereotyping and discrimination than their less-educated counterparts, which is partly due to their greater contact with Whites. Lastly, having greater contact with Whites leads to experiencing more stereotyping and discrimination. Our results are indicative of the ways in which Mexican Americans are racialized in the United States.

  13. Energy Law'88 Proceedings

    International Nuclear Information System (INIS)

    1988-01-01

    This Seminar, divided into 10 topics, covered the legal, economic and trading aspects of oil, coal, natural gas and minerals, nuclear energy was examined from the viewpoint of present government policies, the future of this source of energy and of other sources. The papers presented at the Seminar are reproduced in the Proceedings. (NEA) [fr

  14. FINPIE/97. Workshop proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    This publication contains the proceedings of 1997 Finnish Workshop on Power and Industrial Electronics, held in Espoo, Finland, on 26 August, 1997. The programme consisted of technical sessions on Advanced AC Motor Control, Electric Machines and Drives, Advanced Control and Measurement, Power Electronics Systems, Modelling and Simulation, and Power Converters

  15. EMAC Proceedings, Academic Sessions

    DEFF Research Database (Denmark)

    1997-01-01

    The EMAC Proceedings contains many papers related to digital information processing and telecommunications, reflecting the importance of the telecommunications industry, but also many papers on sensor systems and control systems are included. The papers come from all over Europe, from within...

  16. Trajectories of Mexican American and mainstream cultural values among Mexican American adolescents.

    Science.gov (United States)

    Knight, George P; Basilio, Camille D; Cham, Heining; Gonzales, Nancy A; Liu, Yu; Umaña-Taylor, Adriana J

    2014-12-01

    Mexican Americans are one of the largest and fastest growing ethnic groups in the United States, yet we have limited knowledge regarding changes (i.e., developmental trajectories) in cultural orientation based upon their exposure to the Mexican American and mainstream cultures. We examined the parallel trajectories of Mexican American and mainstream cultural values in a sample of 749 Mexican American adolescents (49 % female) across assessments during the fifth grade (approximately 11 years of age), the seventh grade (approximately 13 years of age) and the tenth grade (approximately 16 years of age). We expected that these values would change over this developmental period and this longitudinal approach is more appropriate than the often used median split classification to identify distinct types of acculturation. We found four distinct acculturation trajectory groups: two trajectory groups that were increasing slightly with age in the endorsement of mainstream cultural values, one of which was relatively stable in Mexican American cultural values while the other was declining in their endorsement of these values; and two trajectory groups that were declining substantially with age in their endorsement of mainstream cultural values, one of which was also declining in Mexican American cultural values and the other which was stable in these values. These four trajectory groups differed in expected ways on a number of theoretically related cultural variables, but were not highly consistent with the median split classifications. The findings highlight the need to utilize longitudinal data to examine the developmental changes of Mexican American individual's adaptation to the ethnic and mainstream culture in order to understand more fully the processes of acculturation and enculturation.

  17. The relationship between Mexican American cultural values and resilience among Mexican American college students: a mixed methods study.

    Science.gov (United States)

    Morgan Consoli, Melissa L; Llamas, Jasmin D

    2013-10-01

    The current study investigated the role of cultural values in the resilience of Mexican American college students. Utilizing mixed methodology, 124 self-identified Mexican American college students were asked to complete an online survey, including a demographic questionnaire, the Resilience Scale, Mexican American Cultural Values Scale, and 2 open-ended questions concerning overcoming adversity and cultural values. As hypothesized, Mexican American traditional cultural values (Familismo, Respeto, Religiosidad, and Traditional Gender Roles) predicted resilience, with Familismo accounting for the majority of the variance. Consensual qualitative research (Hill, Thompson, & Nutt Williams, 1997) was used to identify emergent domains and themes within the open-ended question responses. Traditional Mexican American Value themes included Familismo, Ethnic Identity, Religiosidad, Perseverance, and Respeto. Results highlight the important role that certain Mexican American cultural values play in providing strength for overcoming adversities.

  18. Alkaline pretreatment of Mexican pine residues for bioethanol ...

    African Journals Online (AJOL)

    Alkaline pretreatment of Mexican pine residues for bioethanol production. ... Keywords: Lignocellulosic biomass, alkaline pretreatment, enzymatic hydrolysis, fermentable sugars, fermentation. African Journal of Biotechnology Vol. 12(31), pp.

  19. Localization of amylin-like immunoreactivity in melanocyte-stimulating hormone-containing cells of the pars intermedia but not those of the pars distalis in the axolotl (Ambystoma mexicanum) pituitary.

    Science.gov (United States)

    Suzuki, Hirohumi; Yamamoto, Toshiharu

    2016-04-01

    Immunohistochemical techniques were employed to investigate the distribution of amylin-like immunoreactivity in the axolotl (Ambystoma mexicanum) pituitary. Amylin-immunoreactive cells were observed in the pars intermedia, and these cells were found to be immunoreactive for α-melanocyte-stimulating hormone (αMSH) as well. In contrast, αMSH-immunoreactive cells in the pars distalis were immuno-negaitive for amylin. These light microscopic findings were confirmed by immunoelectron microscopy. Amylin-immunoreactive signals were located on the haloes of presumable secretory granules in association with αMSH-immunoreactive signals in the amylin-positive cells. However, in the pars distalis, the αMSH-positive cells did not contain amylin-immunoreactive secretory granules. Western blot analysis of axolotl pituitary extracts revealed the labeling of a protein band at approximately 10.5-kDa by the anti-rat amylin serum, which was not labeled by the anti-αMSH antibody. These findings indicate that amylin secreted from MSH-producing cells in the pars intermedia may modulate MSH secretion in an autocrine fashion and may participate in MSH functions such as fatty homeostasis together with MSH. Copyright © 2016 Elsevier GmbH. All rights reserved.

  20. 3. Mexican school of nuclear physics

    International Nuclear Information System (INIS)

    Chavez L, E.R.; Hess, P.O.; Martinez Q, E.

    2002-01-01

    The III Mexican School of Nuclear Physics which is directed to those post graduate in Sciences and those of last semesters students of the Physics career or some adjacent career was organized by the Nuclear Physics Division of the Mexican Physics Society, carrying out at November 18-29, 2002 in the installations of the Institute of Physics and the Institute of Nuclear Sciences both in the UNAM, and the National Institute of Nuclear Research (ININ). In this as well as the last version its were offered 17 courses, 9 of them including laboratory practices and the rest were of theoretical character only. This book treats about the following themes: Nuclear physics, Electrostatic accelerators, Cyclotrons, Thermonuclear reactions, Surface barrier detectors, Radiation detection, Neutron detection, Bonner sphere spectrometers, Radiation protection, Biological radiation effects, Particle kinematics, Nucleosynthesis, Plastics, Muons, Quadrupoles, Harmonic oscillators, Quantum mechanics among many other matters. (Author)

  1. Second Mexican School of Nuclear Physics: Notes

    International Nuclear Information System (INIS)

    Aguilera, E.F.; Chavez L, E.R.; Hess, P.O.

    2001-01-01

    The II Mexican School of Nuclear Physics which is directed to those last semesters students of the Physics career or post-graduate was organized by the Nuclear Physics Division of the Mexican Physics Society, carrying out at April 16-27, 2001 in the installations of the Institute of Physics and the Institute of Nuclear Sciences, both in the UNAM, and the National Institute of Nuclear Research (ININ). A first school of a similar level in Nuclear Physics, was carried out in Mexico at 1977 as Latin american School of Physics. This book treats about the following themes: Interactions of radiation with matter, Evaluation of uncertainty in experimental data, Particle accelerators, Notions of radiological protection and dosimetry, Cosmic rays, Basis radiation (environmental), Measurement of excitation functions with thick targets and inverse kinematics, Gamma ray technique for to measure the nuclear fusion, Neutron detection with Bonner spectrometer, Energy losses of alpha particles in nickel. It was held the practice Radiation detectors. (Author)

  2. Energy-urban transition: The Mexican case

    International Nuclear Information System (INIS)

    Paez, Armando

    2010-01-01

    In this paper I present a study regarding the institutional conditions of Mexican cities based on a post-petroleum urban model that considers transport, architecture, urban planning and land use, renewable energy sources, energy saving and efficiency, and urban metabolism issues. The model was constructed with recommendations of authors and organizations that have analysed the energy dimension of cities under an energy-availability, environmental or petroleum-independent view. To make the study I sent a questionnaire to some local governments of all the country. The information indicates that Mexican cities do not have institutional conditions to manage the urban-energy transition that signify the end of cheap oil and the peak of world oil production.

  3. PEMEX: The Mexican state petroleum agency

    International Nuclear Information System (INIS)

    1993-03-01

    An overview is presented of the Mexican state petroleum company PEMEX. The Mexican government created PEMEX through the expropriation of the largely foreign-dominated industry. Mexico is the world's fifth largest crude oil producer, and in 1992 PEMEX had proven reserves of 65.5 billion bbl, crude production of 2.668 million bbl/d, gas production of 3.6 billion cubic feet per day, refined product production of 1.57 million bbl/d and 18 million tonnes of petrochemical production per year. A background is presented of Mexico's economy, followed by discussion of PEMEX's market, the best sales prospects for foreign suppliers, a company profile, financial structure, exploration and production, refining, gas and basic petrochemicals, petrochemicals, transportation and distribution, research and development, recent activities, planned future activities, procurement, and market access. Extensive appendices supply relevant contacts and information. 30 tabs

  4. Electricity supply opportunities -- The Mexican door opens

    International Nuclear Information System (INIS)

    Holland, H.W.

    1993-01-01

    Anyone who assumes that the Mexican market for electrical capacity is just a matter of selling equipment and services is in for a shock. The astute neighbor to the south is exploring privatization in the power sector with a style and flair that is uniquely Mexican. While free market-market forces have, to some extent, already transformed the manner in which new generating capacity is added in the US, a Mexico equivalent will not develop over night. Mexico is no place for the faint of heart. You have to play hard in order to win against competition almost equivalent to that of the US market and have the staying power to be around long enough to reap the rewards. This work presents the author's views concerning the manner in which competition has been introduced within the electricity supply market of the neighbor to the south

  5. Higher risk for obesity among Mexican-American and Mexican immigrant children and adolescents than among peers in Mexico.

    Science.gov (United States)

    Hernández-Valero, María A; Bustamante-Montes, L Patricia; Hernández, Mike; Halley-Castillo, Elizabeth; Wilkinson, Anna V; Bondy, Melissa L; Olvera, Norma

    2012-08-01

    We conducted a cross-sectional study among 1,717 children and adolescents of Mexican origin ages 5-19 years living in Mexico and Texas to explore the influence of country of birth and country of longest residence on their overweight and obesity status. Descriptive statistics were used to compare demographic and anthropometric characteristics of participants born and raised in Mexico (Mexicans), born in Mexico and raised in the United States (Mexican immigrants), and born and raised in the United States (Mexican-Americans). Univariate and multivariate nominal logistic regression was used to determine the demographic predictors of obesity adjusted by country of birth, country of residence, age, and gender. Almost half (48.8%) of the Mexican-Americans and 43.2% of the Mexican immigrants had body mass index at the 85th percentile or above, compared to only 29.3% of the Mexicans (P obese than their Mexican peers [Mexican-Americans: odds ratio (OR) = 2.5 (95% confidence interval [CI] 1.8-3.4); Mexican immigrants: OR = 2.2 (95% CI 1.6-3.0)]. In addition, males were more likely than females to be obese [OR = 1.6 (95% CI 1.2-2.1)], and adolescents 15-19 years of age were less likely than their younger counterparts [OR = 0.5 (95% CI 0.4-0.7)] to be obese. The high prevalence of obesity among children of Mexican origin in the United States is of great concern and underscores the urgent need to develop and implement obesity preventive interventions targeting younger children of Mexican origin, especially newly arrived immigrant children. In addition, future obesity research should take into consideration the country of origin of the study population to develop more culturally specific obesity interventions.

  6. Mexican Marine Corps in the Struggle for Scalable Security and Its Potential as a Guarantor of the Mexican Safety

    Science.gov (United States)

    2013-03-20

    53 G. Elena. Presidente Peña pide a militares a participar en la transformación de México. 1...security of the government of Mexico and the Mexican people until the civilian police is able to do so. 1S. SUBJECT TERMS MAGTF Concept;Mexican...to contribute better to the safety and security of the government of Mexico and the Mexican people until the civilian police is able to do so

  7. Mexican Trends: The Next Five Years,

    Science.gov (United States)

    1985-12-12

    either Argentina (60%) or Chile (75%) and far higher than Brazil (26%), whose total debt was around the same size. Second, of the aggregate Mexican...liberalization policies in Brazil, Argentina, and Chile were hammered into place not by politicians and political parties but by technocrats and...accident that violence has exploded in three border cities ( Agua ; Prieta, Piedras Negras, and San Luis) where the opposition had access to the U.S. media

  8. Narcocultura: A Threat to Mexican National Security?

    Science.gov (United States)

    2012-12-01

    Postcolony: The Zapatistas and Narcocultura,” PhD Essay , University of British Colombia: Department of Political Science, 2011, 18. 7 Rafael López...humorous lyrics or tones in some narcocorridos29 Edberg concludes by stating, “cultural images cross...provided inspiration for the lyrics of classical corridos.63 These original corridos became a source of Mexican national identity and a vehicle for

  9. The Mexican electricity industry - cogeneration potential

    International Nuclear Information System (INIS)

    Monroy, I.L.

    2000-01-01

    A brief history of Mexico's electric power industry is given. Diagrams show (i) the increase in primary energy production from 1990-1998; (ii) energy consumption by sector and (iii) the change in capacity between 1990 and 1998. The projected energy development for 1998-2007 is discussed. The Mexican government has chosen cogeneration to be an important contributor to future energy-efficient power production. Data on installed cogeneration capacity for years 2000 and 2001 are given according to sector

  10. 4. Mexican School of Nuclear Physics. Papers

    International Nuclear Information System (INIS)

    Aguilera, E.F.; Hernandez, E.; Hirsch, J.

    2005-01-01

    The IV Mexican School of Nuclear Physics, organized by the Nuclear Physics Division of the Mexican Physics Society, takes place from June 27 to July 8, 2005 in the Nuclear Sciences and of Physics Institutes of the UNAM and in the National Institute of Nuclear Research (ININ). This school, as the previous ones, it was guided the students of the last semesters of the career of Physics, of the Post grade of the same specialty, and of other adjacent careers. To give the students a current vision of some of the topics more important of the nuclear physics and their relationship with other near areas of the physics it was the objective of this School. The School covered a wide range of theoretical and experimental courses, imparted in its majority by Mexican expert professor-investigators in the matter to who we thank them the one effort and the quality of their presentations, reflected in the content of this document. The answer of the students to the convocation was excellent, 31 students presented application for admission coming from the following institutions: Meritorious Autonomous University de Puebla, National Institute of Nuclear Research, Technological Institute of Orizaba, National Polytechnic Institute, The University of Texas at Brownsville, Autonomous University of the State de Mexico, Autonomous University of the State of Morelos, Autonomous University of Baja California, Autonomous University of San Luis Potosi, University of Guadalajara, University of Guanajuato, National Autonomous University of Mexico, University of Texas, at El Paso and University Veracruzana. They were admitted to the 22 students with the higher averages qualifications of the list of applicants. The organizers of this school thank the financial support granted by the following sponsor institutions: Nuclear Sciences Institute, UNAM, Physics Institute of UNAM, Coordination of the Scientific Research UNAM, National Institute of Nuclear Research, Nuclear Physics Division of the Mexican

  11. 4. Mexican School of Nuclear Physics

    International Nuclear Information System (INIS)

    Aguilera, E.F.; Hernandez, E.; Hirsch, J.G. -mail: svp@nuclear.inin.mx

    2005-01-01

    The IV Mexican School of Nuclear Physics, organized by the Nuclear Physics Division of the Mexican Physics Society, taken place from June 27 to July 8, 2005 in the Institute of Nuclear Sciences and the Institute of Physics of the UNAM and in the National Institute of Nuclear Research (ININ). This school, as the previous ones, it was guided to the students of the last semesters of the career of Physics, of the Post grade of the same specialty, and of other adjacent careers. To give the students a current vision of some of the topics more important of the nuclear physics and their relationship with other near areas of the physics it was the objective of this School. The School covered a wide range of theoretical and experimental courses, imparted in its majority by Mexican expert professor-investigators in the subject to whom we thank them the one effort and the quality of their presentations, reflected in the content of this document. The answer of the students to the convocation was excellent, 31 students presented application for admission coming from the following institutions: Meritorious Autonomous University of Puebla, National Institute of Nuclear Research, Technological Institute of Orizaba, National Polytechnic Institute, The University of Texas at Brownsville, Autonomous University of the State de Mexico, Autonomous University of the State of Morelos, Autonomous University of Baja California, Autonomous University of San Luis Potosi, University of Guadalajara, University of Guanajuato, National Autonomous University of Mexico, University of Texas, at El Paso and University Veracruzana. They were admitted to those 22 students with the higher averages qualifications of the list of applicants. The organizers of this school thank the financial support granted by the following sponsor institutions: Institute of Nuclear Sciences, UNAM, Institute of Physics, UNAM, Coordination of the Scientific Research, UNAM, National Institute of Nuclear Research, Nuclear

  12. New Mexicans debate nuclear waste disposal

    International Nuclear Information System (INIS)

    Lepkowski, W.

    1979-01-01

    A brief survey of the background of the Waste Isolation Plant (WIPP) at Carlsbad, New Mexico and the forces at play around WIPP is presented. DOE has plans to establish by 1988 an underground repository for nuclear wastes in the salt formations near Carlsbad. Views of New Mexicans, both pro and con, are reviewed. It is concluded that DOE will have to practice public persuasion to receive approval for the burial of wastes in New Mexico

  13. Type 2 diabetes mortality at Mexican borders

    OpenAIRE

    Manzanares Rivera, José Luis

    2017-01-01

    Abstract:Objective: To analyze type II diabetes mortality rates geographic distribution and evolution in time across both Mexican border regions during the period 1998-2013.Methods: The work is based on exploratory and inferential data analysis conducted using death reports from the national health information system. The analysis considers social determinants of health as a theoretical paradigm and includes microdata on consumption patterns at household level for the US-Mexico and Mexico- Gu...

  14. Genetic analysis of Mexican Criollo cattle populations.

    Science.gov (United States)

    Ulloa-Arvizu, R; Gayosso-Vázquez, A; Ramos-Kuri, M; Estrada, F J; Montaño, M; Alonso, R A

    2008-10-01

    The objective of this study was to evaluate the genetic structure of Mexican Criollo cattle populations using microsatellite genetic markers. DNA samples were collected from 168 animals from four Mexican Criollo cattle populations, geographically isolated in remote areas of Sierra Madre Occidental (West Highlands). Also were included samples from two breeds with Iberian origin: the fighting bull (n = 24) and the milking central American Criollo (n = 24) and one Asiatic breed: Guzerat (n = 32). Genetic analysis consisted of the estimation of the genetic diversity in each population by the allele number and the average expected heterozygosity found in nine microsatellite loci. Furthermore, genetic relationships among the populations were defined by their genetic distances. Our data shows that Mexican cattle populations have a relatively high level of genetic diversity based either on the mean number of alleles (10.2-13.6) and on the expected heterozygosity (0.71-0.85). The degree of observed homozygosity within the Criollo populations was remarkable and probably caused by inbreeding (reduced effective population size) possibly due to reproductive structure within populations. Our data shows that considerable genetic differentiation has been occurred among the Criollo cattle populations in different regions of Mexico.

  15. The United Mexican States: an update.

    Science.gov (United States)

    Hakkert, R; Aguirre, E J

    1988-09-01

    Although the popular North American opinion of Mexico is one that paints a picture of a poor, disadvantaged country, South America sees Mexico has a richer more prosperous nation. It is observed that only in the Latin American countries of Venezuela, Suriname and Trinidad and Tobago do consumers have higher incomes than Mexican consumers. Moreover, while millions of Mexicans migrate to the United States to seek a better standard of living, several thousand Central American refugees illegally migrate to Mexico in search of a better life. This better life includes an increased age of lie expectancy from 51 years in the 1950s to 64 years in the late 1970s. There have also been improvements in health care and school enrollments and in the low cost availability of education. Tourism and the prospect of the manufacturing of energy are significant, positive factors working in favor of an improved Mexican economy and a higher overall quality of life. However, Mexico faces serious problems such as a mounting foreign debt. Also rising is Mexico's population which has doubled since 1964 and which continues to grow at a rate of 1.9%. Economic programs and reforms and family development planning have been instituted in response to the countries' current recession and population growth and have begun to show positive results.

  16. Participants in urban Mexican male homosexual encounters.

    Science.gov (United States)

    Carrier, J M

    1971-12-01

    Preliminary data are presented on 53 urban Mexican males interviewed during 1970-1971 in a study of homosexual encounters in a large Mexican city. These data are compared with data from recent studies in the United States and England of male homosexual behavior. Although preliminary and limited, the Mexican data indicate that cultural factors are important determinants of life styles and sex practices of homosexual males. Forty-eight of the 53 (90%) preferred and usually practiced anal intercourse, four preferred oral contacts, and one preferred mutual masturbation. Interviewees were also grouped according to major type of sex activity during the first sustained year of homosexual activity after puberty. One intragroup comparison indicates significant differences between anal active and anal passive interviewees. For example, as children anal passive subjects had significantly more homosexual contacts with adults; they also considered themselves more effeminate and as children were more involved with female sex-typed activities. Comparison of data from the English and United States studies with the present data suggests that preference for a particular sexual technique is not as developed in the former two countries; when there is a preference, it is not usually for anal intercourse.

  17. Quantum interaction. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Bruza, Peter [Queensland Univ. of Technology, Brisbane (Australia). Faculty of Science and Technology; Sofge, Donald [Navy Center for Applied Research in Artificial Intelligence, Washington, DC (United States). Naval Research Lab.; Lawless, William [Paine Coll., Augusta, GA (United States); Rijsbergen, Keith van [Glasgow Univ. (United Kingdom). Dept. of Computing Science; Klusch, Matthias (eds.) [German Research Center for Artificial Intelligence, Saarbruecken (Germany)

    2009-07-01

    This book constitutes the refereed proceedings of the Third International Symposium on Quantum Interaction, QI 2009, held in Saarbruecken, Germany, in March 2009. The 21 revised full papers presented together with the 3 position papers were carefully reviewed and selected from numerous submissions. The papers show the cross-disciplinary nature of quantum interaction covering topics such as computation, cognition, decision theory, information retrieval, information systems, social interaction, computational linguistics and finance. (orig.)

  18. Workshop UNK-600 (proceedings)

    International Nuclear Information System (INIS)

    Zajtsev, A.M.; Bitykov, S.I.

    1994-01-01

    Proceedings are presented of the workshop devoted to the accelerating storage complex of IHEP (UNK-600). In the first section is given the information on the present status of the UNK-600 and particle channels design and on the adopted experiment NEPTUN-A. In the papers of the second section are discussed hadron physics investigations at 600 GeV. Experiments in the neutrino and muon beams are analyzed. A possible program of studying the charged kaon rare decays is described

  19. Quantum interaction. Proceedings

    International Nuclear Information System (INIS)

    Bruza, Peter; Rijsbergen, Keith van

    2009-01-01

    This book constitutes the refereed proceedings of the Third International Symposium on Quantum Interaction, QI 2009, held in Saarbruecken, Germany, in March 2009. The 21 revised full papers presented together with the 3 position papers were carefully reviewed and selected from numerous submissions. The papers show the cross-disciplinary nature of quantum interaction covering topics such as computation, cognition, decision theory, information retrieval, information systems, social interaction, computational linguistics and finance. (orig.)

  20. National Mexican Tourism Policy and North American Second Homeowners In Mexico: Local Tourism Development and Mexican Identity (Chapter 6)

    DEFF Research Database (Denmark)

    Clausen, Helene Balslev

    2018-01-01

    . Still the Mexican state does not seize the second home owners as a resource and ‘producers’ rather only as consumers of different Mexican objects, food etc. The chapter addresses this research gap and proposes rather than only perceive North American second home owners as part of tourism development...... participate in reshaping and reconfigure public policy and Mexican culture/identity construction. The purpose of the chapter is to explore the role of the North American second home owners and their impact on the planning and regulation of Mexican state policies, and how they might reconfigure practices and...

  1. Long-term surveillance plan for the Mexican Hat disposal site Mexican Hat, Utah

    International Nuclear Information System (INIS)

    1997-06-01

    This long-term surveillance plan (LTSP) describes the U.S. Department of Energy's (DOE) long-term care program for the Uranium Mill Tailings Remedial Action (UMTRA) Project Mexican Hat, Utah, disposal site. This LSTP describes the long-term surveillance program the DOE will implement to ensure the Mexican Hat disposal site performs as designed and is cared for in a manner that protects the public health and safety and the environment. Before each disposal site is licensed for custody and long-term care, the Nuclear Regulatory Commission (NRC) requires the DOE to submit such a site-specific LTSP

  2. Proceedings of the Fourth Compton Symposium. Proceedings

    International Nuclear Information System (INIS)

    Dermer, C.D.; Strickman, M.S.; Kurfess, J.D.

    1997-01-01

    These proceedings represent the papers presented at the Fourth Compton Symposium held in Williamsburg, Virginia in April, 1997. This symposium gives the latest development in gamma ray astronomy and summarizes the results obtained by the Compton Gamma Ray Observatory. One of the missions of the Observatory has been the study of physical processes taking place in the most dynamic sites in the Universe, including supernovae, novae, pulsars, black holes, active galaxies, and gamma-ray bursts. The energies covered range from hard X-ray to gamma-ray regions from 15 KeV to 30 GeV. The Burst and Transient Experiment (BASTE) measures brightness variations in gamma-ray bursts and solar flares. The Oriented Scintillation Spectroscopy Experiment (OSSE), measures spectral output of astrophysical sources in the 0.05 to 10 MeV range. The Imaging Compton Telescope (COMPTEL) detects gamma-rays and performs sky survey in the energy range 1 to 30 MeV. The Energetic Gamma Ray Experiment Telescope (EGRET) covers the broadest energy range from 20 MeV to 30 GeV. The papers presented result from all of the above. There were 249 papers presented and out of these, 6 have been abstracted for the Energy, Science and Technology database

  3. Another Mexican birthweight paradox? The role of residential enclaves and neighborhood poverty in the birthweight of Mexican-origin infants.

    Science.gov (United States)

    Osypuk, Theresa L; Bates, Lisa M; Acevedo-Garcia, Dolores

    2010-02-01

    Examining whether contextual factors influence the birth outcomes of Mexican-origin infants in the US may contribute to assessing rival explanations for the so-called Mexican health paradox. We examined whether birthweight among infants born to Mexican-origin women in the US was associated with Mexican residential enclaves and exposure to neighborhood poverty, and whether these associations were modified by nativity (i.e. mother's place of birth). We calculated metropolitan indices of neighborhood exposure to Mexican-origin population and poverty for the Mexican-origin population, and merged with individual-level, year 2000 natality data (n=490,332). We distinguished between neighborhood exposure to US-born Mexican-origin population (i.e. ethnic enclaves) and neighborhood exposure to foreign-born (i.e. Mexico-born) Mexican-origin population (i.e. immigrant enclaves). We used 2-level hierarchical linear regression models adjusting for individual, metropolitan, and regional covariates and stratified by nativity. We found that living in metropolitan areas with high residential segregation of US-born Mexican-origin residents (i.e. high prevalence of ethnic enclaves) was associated with lower birthweight for infants of US-born Mexican-origin mothers before and after covariate adjustment. When simultaneously adjusting for exposure to ethnic and immigrant enclaves, the latter became positively associated with birthweight and the negative effect of the former increased, among US-born mothers. We found no contextual birthweight associations for mothers born in Mexico in adjusted models. Our findings highlight a differential effect of context by nativity, and the potential health effects of ethnic enclaves, which are possibly a marker of downward assimilation, among US-born Mexican-origin women. Copyright 2009 Elsevier Ltd. All rights reserved.

  4. Perceived social stress, pregnancy-related anxiety, depression and subjective social status among pregnant Mexican and Mexican American women in south Texas.

    Science.gov (United States)

    Fleuriet, K Jill; Sunil, T S

    2014-05-01

    The purpose of this study was to determine differences in subjective social status, perceived social stress, depressive symptoms, and pregnancy-related anxiety between pregnant Mexican American and Mexican immigrant women. Three hundred pregnant Mexican immigrant and Mexican American women in South Texas were surveyed for pregnancy-related anxiety, perceived social stress, depressive symptoms, and subjective social status. Pregnant Mexican immigrant women had higher levels of pregnancy-related anxiety and lower levels of depression and perceived social stress than pregnant Mexican American women. Change in these variables among Mexican immigrant women was relatively linear as time of residence in the United States increased. Mexican immigrant and Mexican American women had significantly different correlations between subjective social status, self-esteem and perceived social stress. Results indicate that subjective social status is an important psychosocial variable among pregnant Hispanic women. Results contribute to ongoing efforts to provide culturally responsive prenatal psychosocial support services.

  5. Women's Networks and the Social Needs of Mexican Immigrants.

    Science.gov (United States)

    O'Connor, Mary I.

    1990-01-01

    Reports on the persistence of a two-tiered economic and political system that routinely excludes Mexican immigrants. Focuses on the predominantly female employees of a wholesale nursery in Carpinteria (California), who have adapted the Mexican tradition of "confianza"-based relationships to form networks that facilitate communication and…

  6. Losing American Students, Mexican Universities Struggle against a Scary Image

    Science.gov (United States)

    Ambrus, Steven

    2012-01-01

    Like most Mexicans, Eugenio Yarce has been deeply affected by the violence between drug cartels and the Mexican army, which has filled news coverage with accounts of kidnappings, assassinations, and torture. But for Mr. Yarce, deputy rector for outreach here at the private Autonomous Popular University of the State of Puebla, or Upaep, the…

  7. Mexican-Origin Women's Employment Instability. Working Paper No. 51.

    Science.gov (United States)

    De Anda, Roberto M.

    This paper compares the causes and consequences of employment instability among Mexican-origin women, White women, and White men. Data came from the work experience supplement in the March 1995 file of the Current Population Survey for a sample that included 1,399 Mexican-origin women, 17,092 White women, and 24,440 White men. All were experienced…

  8. The Mexican American in Higher Education: Implications for Educators.

    Science.gov (United States)

    Muhs, William F.; And Others

    1979-01-01

    Literature reviews suggest that Mexican-American students place more emphasis on cooperation and group than on individual achievement. Education may be enhanced when teachers reinforce "successful behavior." Problems may arise using U.S.-based theories of "democratic" leadership styles because Mexican-American culture places emphasis on…

  9. Mexican Art and Architecture Databases: Needs, Achievements, Problems.

    Science.gov (United States)

    Barberena, Elsa

    At the international level, a lack of diffusion of Mexican art and architecture in indexes and abstracts has been detected. Reasons for this could be lack of continuity in publications, the use of the Spanish language, lack of interest in Mexican art and architecture, and sporadic financial resources. Nevertheless, even though conditions are not…

  10. Transformative, Mixed Methods Checklist for Psychological Research with Mexican Americans

    Science.gov (United States)

    Canales, Genevieve

    2013-01-01

    This is a description of the creation of a research methods tool, the "Transformative, Mixed Methods Checklist for Psychological Research With Mexican Americans." For conducting literature reviews of and planning mixed methods studies with Mexican Americans, it contains evaluative criteria calling for transformative mixed methods, perspectives…

  11. Storytelling in Mexican Homes: Connections between Oral and Literacy Practices

    Science.gov (United States)

    Reese, Leslie

    2012-01-01

    The study focuses on storytelling among Mexican families, documenting the frequency of storytelling in the homes of working- and middle-class Mexican families, the range of topics of the stories, characteristics and genres of stories, and intergenerational continuity of storytelling practices. Also examined are potential associations between…

  12. The Mexican Committee against Racism and What It Reveals about Relations between Mexican and American Jews

    Directory of Open Access Journals (Sweden)

    Ariela Katz Gugenheim

    2012-10-01

    Full Text Available This work reconstructs the origin, organization, development, and disappearance of the Mexican Committee against Racism (Comité Mexicano contra el Racismo, CMR, active in Mexico City from 1944 to 1946, inthe context of the relations between a leading Jewish organization in the United States and a Mexican Jewish institution. The CMR appears in historiography as a Mexican anti-fascist institution, but this research reveals that it was conceived, implemented, financed, and supervised by the American Jewish Committee (AJC, a Jewish social action organization based in the United States, with the aim of fighting against racist and anti-Semitic prejudices, creating a friendly climate towards Jewish-refugee immigration, and quelling anti-American feelings in Mexico. The AJC's involvement was kept a secret for Mexicans in general and for the Jewish community in Mexico. Drawing on archives in Mexico and the United States, this work details the reasons that led to its organization, describes its implementation, explains why the AJC's involvement was kept a secret, and why the CMR failed to prosper and eventually disappeared.

  13. Parental Factors Associated with Mexican American Adolescent Alcohol Use

    Directory of Open Access Journals (Sweden)

    Cristina Mogro-Wilson

    2013-01-01

    Full Text Available The purpose of this study is to further the understanding of how parenting and the relationship between the parent and the youth influence adolescent alcohol use in Mexican American families, with particular attention to acculturation. Results indicated that parental warmth is a strong factor in predicting adolescent alcohol use among Mexican adolescents. The parent-youth relationship played an important role in lowering alcohol use for Mexican American youth. Acculturation has an impact on the level of warmth, control, and the parent-youth relationship for Mexican American families. Findings indicate that there are unique family mechanisms for Mexican American families that should be considered when developing prevention and treatment options.

  14. [Dichotic perception of Mandarin third tone by Mexican Chinese learners].

    Science.gov (United States)

    Wang, Hongbin

    2014-05-01

    To investigate the relationship between the advantage ear (cerebral hemisphere) of Spanish-speaking Mexican learners and the third Chinese tone. Third tone Chinese vowel syllables were used as experimental materials with dichotic listening technology to test the Spanish-speaking Mexican Chinese learners (20-32 years old) who studied Chinese about 20 h. In terms of error rates to identify the third Chinese tone, the Spanish-speaking Mexican Chinese learners's reaction to the third tone suggested that their left ears were the advantageous ear (the right cerebral hemisphere) (Z=-2.091, P=0.036). The verbal information of tones influenced the perception of Mexican Chinese learners' mandarin tones. In the process of learning mandarin tones, Mexican Chinese learners gradually formed the category of tones.

  15. ITER council proceedings: 1997

    International Nuclear Information System (INIS)

    1997-01-01

    This volume of the ITER EDA Documentation Series presents records of the 12th ITER Council Meeting, IC-12, which took place on 23-24 July, 1997 in Tampere, Finland. The Council received from the Parties (EU, Japan, Russia, US) positive responses on the Detailed Design Report. The Parties stated their willingness to contribute to fulfil their obligations in contributing to the ITER EDA. The summary discussions among the Parties led to the consensus that in July 1998 the ITER activities should proceed for additional three years with a general intent to enable an efficient start of possible, future ITER construction

  16. Proceedings of biodegradation

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    This book contains the proceedings of Biodegradation. Topics include:biodegradation using the tools of biotechnology, basic science aspects of biodegradation, the physiological characteristics of microorganisms, the use of selective techniques that enhance the process of microbial evolution of biodegradative genes in nature, the genetic characteristics of microorganisms allowing them to biodegrade both natural and synthetic toxic chemicals, the molecular techniques that allow selective assembly of genetic segments form a variety of bacterial strains to a single strain, and methods needed to advance biodegradation research as well as the high-priority chemical problems important to the Department of Defense or to the chemical industry

  17. Engineering assessment of inactive uranium mill tailings: Mexican Hat Site, Mexican Hat, Utah

    International Nuclear Information System (INIS)

    1981-09-01

    Ford, Bacon and Davis Utah Inc. has reevaluated the Mexican Hat site in order to revise the March 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Mexican Hat, Utah. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 2.2 million tons of tailings at the Mexican Hat site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material to removal of the tailings to remote disposal sites and decontamination of the tailings site. Cost estimates for the four options range from about $15,200,000 for stabilization in place, to about $45,500,000 for disposal at a distance of about 16 mi. Three principal alternatives for the reprocessing of the Mexican Hat tailings were examined: heap leaching; treatment at an existing mill; and reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovered would be about $115/lb of U 3 O 8 whether by heap leach or conventional plant processes. The spot market price for uranium was $25/lb early in 1981. Reprocessing the Mexican Hat tailings for uranium recovery is not economically attractive under present conditions

  18. Idioms of Distress Among Depressed White-Non-Mexican and Mexican-Origin Older Men.

    Science.gov (United States)

    Apesoa-Varano, Ester Carolina; Barker, Judith C; Unutzer, Jurgen; Aguilar-Gaxiola, Sergio; Johnson, Megan Dwight; Tran, Cindy; Guarnaccia, Peter; Hinton, Ladson

    2015-09-01

    Older men are less likely than older women to receive depression treatment. Latino older men in particular have been found to have significantly lower rates of depression treatment than their white-non-Mexican (WNM) counterparts. Prior research has shown that men are less likely than women to express overt affect and/or report depression symptoms that may prompt primary care physicians' inquiry about depression. Previous studies have overlooked the idioms of distress common among older men. This study investigates: a) the range of idioms of distress that emerge in the narratives of depressed older men, and b) the use of these idioms among depressed WNM and Mexican-origin older men. The present report is based on qualitative data collected through the Men's Health and Aging Study (MeHAS), a mixed-method study of clinically depressed WNM and Mexican-origin older (65 and above) men recruited in primary care settings. Qualitative analysis of 77 interviews led to identification of idioms of distress and informed idiom categories. Study findings show that: a) both groups of men utilized a range of idioms of distress that met current DSM criteria for depression, b) both groups were also likely to utilize idioms that feel outside clinical depression criteria, and c) there were similarities as well as differences between WNM and Mexican-origin men. This study provides a larger vocabulary that clinicians might consider in recognizing depression and initiating depression care for older men from diverse ethnic backgrounds. This is important to improve depression care among older men in general and those of Mexican-origin in particular.

  19. Prediabetes, undiagnosed diabetes, and diabetes among Mexican adults: findings from the Mexican Health and Aging Study.

    Science.gov (United States)

    Kumar, Amit; Wong, Rebeca; Ottenbacher, Kenneth J; Al Snih, Soham

    2016-03-01

    The purpose of the study was to examine the prevalence and determinants of prediabetes, undiagnosed diabetes, and diabetes among Mexican adults from a subsample of the Mexican Health and Aging Study. We examined 2012 participants from a subsample of the Mexican Health and Aging Study. Measures included sociodemographic characteristics, body mass index, central obesity, medical conditions, cholesterol, high-density lipoprotein cholesterol, hemoglobin A1c, and vitamin D. Logistic regression was performed to identify factors associated with prediabetes, undiagnosed diabetes, and self-reported diabetes. Prevalence of prediabetes, undiagnosed, and self-reported diabetes in this cohort was 44.2%, 18.0%, and 21.4%, respectively. Participants with high waist-hip ratio (1.61, 95% confidence interval [CI] = 1.05-2.45) and high cholesterol (1.85, 95% CI = 1.36-2.51) had higher odds of prediabetes. Overweight (1.68, 95% CI = 1.07-2.64), obesity (2.38, 95% CI = 1.41-4.02), and high waist circumference (1.60, 95% CI = 1.06-2.40) were significantly associated with higher odds of having undiagnosed diabetes. Those residing in a Mexican state with high U.S. migration had lower odds of prediabetes (0.61, 95% CI = 0.45-0.82) and undiagnosed diabetes (0.53, 95% CI = 0.41-0.70). Those engaged in regular physical activity had lower odds of undiagnosed diabetes (0.74, 95% CI = 0.57-0.97). There is a high prevalence of prediabetes and undiagnosed diabetes among Mexican adults in this subsample. Findings suggest the need for resources to prevent, identify, and treat persons with prediabetes and undiagnosed diabetes. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Engineering assessment of inactive uranium mill tailings: Mexican Hat site, Mexican Hat, Utah. Summary

    International Nuclear Information System (INIS)

    1981-09-01

    Ford, Bacon and Davis Utah Inc. has reevaluated the Mexican Hat site in order to revise the March 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Mexican Hat, Utah. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 2.2 million tons of tailings at the Mexican Hat site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material to removal of the tailings to remote disposal sites and decontamination of the tailings site. Cost estimates for the four options range from about $15,200,000 for stabilization in place, to about $45,500,000 for disposal at a distance of about 16 mi. Three principal alternatives for the reprocessing of the Mexican Hat tailings were examined: (a) heap leaching; treatment at an existing mill; and reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovered would be about $115/lb of U 3 O 8 whether by heap leach or conventional plant processes. The spot market price for uranium was $25/lb early in 1981. Reprocessing the Mexican Hat tailings for uranium recovery is not economically attractive under present conditions

  1. San Pedro Martir Telescope: Mexican design endeavor

    Science.gov (United States)

    Toledo-Ramirez, Gengis K.; Bringas-Rico, Vicente; Reyes, Noe; Uribe, Jorge; Lopez, Aldo; Tovar, Carlos; Caballero, Xochitl; Del-Llano, Luis; Martinez, Cesar; Macias, Eduardo; Lee, William; Carramiñana, Alberto; Richer, Michael; González, Jesús; Sanchez, Beatriz; Lucero, Diana; Manuel, Rogelio; Segura, Jose; Rubio, Saul; Gonzalez, German; Hernandez, Obed; García, Mary; Lazaro, Jose; Rosales-Ortega, Fabian; Herrera, Joel; Sierra, Gerardo; Serrano, Hazael

    2016-08-01

    The Telescopio San Pedro Martir (TSPM) is a new ground-based optical telescope project, with a 6.5 meters honeycomb primary mirror, to be built in the Observatorio Astronomico Nacional on the Sierra San Pedro Martir (OAN-SPM) located in Baja California, Mexico. The OAN-SPM has an altitude of 2830 meters above sea level; it is among the best location for astronomical observation in the world. It is located 1830 m higher than the atmospheric inversion layer with 70% of photometric nights, 80% of spectroscopic nights and a sky brightness up to 22 mag/arcsec2. The TSPM will be suitable for general science projects intended to improve the knowledge of the universe established on the Official Mexican Program for Science, Technology and Innovation 2014-2018. The telescope efforts are headed by two Mexican institutions in name of the Mexican astronomical community: the Universidad Nacional Autonoma de Mexico and the Instituto Nacional de Astrofisica, Optica y Electronica. The telescope has been financially supported mainly by the Consejo Nacional de Ciencia y Tecnologia (CONACYT). It is under development by Mexican scientists and engineers from the Center for Engineering and Industrial Development. This development is supported by a Mexican-American scientific cooperation, through a partnership with the University of Arizona (UA), and the Smithsonian Astrophysical Observatory (SAO). M3 Engineering and Technology Corporation in charge of enclosure and building design. The TSPM will be designed to allow flexibility and possible upgrades in order to maximize resources. Its optical and mechanical designs are based upon those of the Magellan and MMT telescopes. The TSPM primary mirror and its cell will be provided by the INAOE and UA. The telescope will be optimized from the near ultraviolet to the near infrared wavelength range (0.35-2.5 m), but will allow observations up to 26μm. The TSPM will initially offer a f/5 Cassegrain focal station. Later, four folded Cassegrain and

  2. Prevalence of metabolic syndrome among elderly Mexicans.

    Science.gov (United States)

    Ortiz-Rodríguez, María Araceli; Yáñez-Velasco, Lucía; Carnevale, Alessandra; Romero-Hidalgo, Sandra; Bernal, Demetrio; Aguilar-Salinas, Carlos; Rojas, Rosalba; Villa, Antonio; Tur, Josep A

    2017-11-01

    One of the most prevalent chronic diseases among elderly population is the Metabolic Syndrome (MetS). The aim of this study was to assess the prevalence of MetS and associated factors among Mexican elderly people. Cross-sectional survey carried out in Mexico (2007). A random sample (n=516) of the elderly population (≥65years; 277 female, 239 male) was interviewed. Anthropometric and analytical measurements, and a general questionnaire incorporating questions related to socio-demographic and life-style factors were used. MetS definition AHA/NHLBI/IDF was applied. The prevalence of MetS in the elderly (≥65years) was of 72.9% (75.7% men; 70.4% women). Participants with values above MetS cut-off points were 92.4% (hypertension), 77.8% (hypertriglyceridemia), 77.1% (low HDL-cholesterol), 71.1% (hyperglycaemia), and 65.4% (central obesity). People with MetS showed higher values of anthropometric and biochemical variables than those without MetS, except for the height, cholesterol and creatinine. Mid-high education level (9-12 years), no smokers and former smokers, and Central-Western inhabitants of Mexico were associated with MetS components. BMI status was the main determinant of MetS prevalence and MetS components. The reported prevalence of MetS among the elderly Mexican population was higher than those previously obtained in the geographical area, showing a major public health problem in Mexican elders. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. 60Co retention by Mexican montmorillonites

    International Nuclear Information System (INIS)

    Pacheco, G.; Martinez, V.; Bosch, P.; Bulbulian, S.

    1995-01-01

    Radioactive elements may be retained by clays. The ability of natural Mexican clays to retain radioactive Co from aqueous solutions, is discussed. Experiments were performed with solutions containing labeled cobalt. The effect of contact time on Co 2+ retention was studied. It was found that the Co 2+ uptake value in dehydrated montmorillonites is between 0.30 and 0.70 meq g -1 of clay. A sorption sequence was obtained for the various clays. The samples were characterized, before and after cobalt exchange, by X-ray diffraction. (author). 7 refs., 3 figs., 3 tabs

  4. Women writers and the Mexican Revolution

    OpenAIRE

    Thornton, Niamh

    2003-01-01

    The aim of this thesis is to explore how women are represented in novels written by women which have conflict as their central thematic concern. Consequently, it was necessary to examine the context in which these texts were written and how they compare to texts written by men based on the same period. As a result I studied the novela de la revolución as a genre in Mexico, accessing this material in Irish, British and Mexican libraries. Having established thematic predecessors, I approached t...

  5. Natural Variability of Mexican Forest Fires

    Science.gov (United States)

    Velasco-Herrera, Graciela; Velasco Herrera, Victor Manuel; Kemper-Valverdea, N.

    The purpose of this paper was 1) to present a new algorithm for analyzing the forest fires, 2) to discuss the present understanding of the natural variability at different scales with special emphasis on Mexico conditions since 1972, 3) to analyze the internal and external factors affecting forest fires for example ENSO and Total Solar Irradiance, and 4) to discuss the implications of this knowledge, on research and on restoration and management methods, which purpose is to enhance forest biodiversity conservation. 5) We present an estimate of the Mexican forest fires for the next decade. These results may be useful to minimize human and economic losses.

  6. Usual Vitamin Intakes by Mexican Populations.

    Science.gov (United States)

    Pedroza-Tobías, Andrea; Hernández-Barrera, Lucía; López-Olmedo, Nancy; García-Guerra, Armando; Rodríguez-Ramírez, Sonia; Ramírez-Silva, Ivonne; Villalpando, Salvador; Carriquiry, Alicia; Rivera, Juan A

    2016-09-01

    In the past several years, the consumption of high-energy, nutrient-poor foods has increased globally. Dietary intake data collected by the National Health and Nutrition Survey (ENSANUT) 2012 provide information to assess the quality of the Mexican diet and to guide food and nutrition policy. The aim was to describe the usual intake and the prevalence of inadequate intakes of vitamins for the overall Mexican population and by subgroups defined by sex, age, region, urban or rural areas, and socioeconomic status (SES). ENSANUT 2012 is a cross-sectional probabilistic survey representative of the Mexican population. Dietary information was collected by using the 24-h recall automated multiple-pass method (n = 10,096) with a repeated measurement on a subsample (n = 889) to permit adjustment for intraindividual variability with the use of the Iowa State University method. Mean usual intakes and the prevalence of inadequate intakes of thiamin, riboflavin, niacin, folate, and vitamins A, D, E, C, B-6, and B-12 were calculated for children aged 1-4 y (CH1-4y), children aged 5-11 y (CH5-11y), adolescents aged 12-19 y, and adults aged ≥20 y. In all of the age groups, prevalences of inadequate intakes of vitamins D and E were the highest (77-99% of adults and adolescents and 53-95% of CH5-11y and CH1-4y) and those of folate and vitamin A were intermediate (47-70% of adults and adolescents, 15-23% of CH5-11y and 8-13% of CH1-4y), whereas those of thiamin, riboflavin, niacin, and vitamins B-6, B-12, and C were the lowest (0-37% of adults, 1-27% of adolescents, and 0-2.4% of CH5-11y and CH1-4y). With few exceptions, the highest prevalences of inadequate intakes for vitamins were observed in the poorest populations (rural South region and the lowest tertile of SES). The intake of vitamins among Mexicans is inadequate overall. Information collected by ENSANUT can help target food assistance programs and develop strategies to prevent vitamin deficiencies. © 2016 American Society

  7. Mexican waves in an excitable medium.

    Science.gov (United States)

    Farkas, I; Helbing, D; Vicsek, T

    2002-09-12

    The Mexican wave, or La Ola, which rose to fame during the 1986 World Cup in Mexico, surges through the rows of spectators in a stadium as those in one section leap to their feet with their arms up, and then sit down again as the next section rises to repeat the motion. To interpret and quantify this collective human behaviour, we have used a variant of models that were originally developed to describe excitable media such as cardiac tissue. Modelling the reaction of the crowd to attempts to trigger the wave reveals how this phenomenon is stimulated, and may prove useful in controlling events that involve groups of excited people.

  8. Alcohol Use Disorders in National Samples of Mexicans and Mexican-Americans: The Mexican National Addiction Survey and the U.S. National Alcohol Survey

    Science.gov (United States)

    Borges, Guilherme; Medina-Mora, Maria Elena; Lown, Anne; Ye, Yu; Robertson, Marjorie J.; Cherpitel, Cheryl; Greenfield, Tom

    2006-01-01

    The authors show associations between immigration and alcohol disorders using data from the 1995 and 2000 U.S. National Alcohol Surveys and the 1998 Mexico National Household Survey on Addictions. The prevalence of alcohol dependence was 4.8% for the Mexicans, 4.2% for the Mexico-born immigrants, and 6.6% for the U.S.-born Mexican Americans. They…

  9. Auroral Tomography Workshop, Proceedings

    International Nuclear Information System (INIS)

    Steen, Aa.

    1993-08-01

    In ionospheric and atmospheric physics the importance of multi-station imaging has grown as a consequence of the availability of scientific grade CCD cameras with digital output and affordable massive computing power. Tomographic inversion techniques are used in many different areas, e.g. medicine, plasma research and space physics. The tomography workshop was announced to gather a limited group of people interested in auroral tomography or tomographic inversion methods in general. ALIS (Auroral Large Imaging System) is a multi-station ground-based system developed primarily for three-dimensional auroral imaging, however other non-auroral objects can be studied with ALIS, e.g. stratospheric clouds. Several of the contributions in the workshop dealt with problems related to geometries similar to the ALIS-configuration. The Proceedings contain written contributions received either in abstract form or as full papers. The Proceedings also contain contributions intended for the Workshop but not presented due to the absence of the speaker. Separate abstracts have been prepared for 15 of the 17 papers

  10. Proceedings of the 15th workshop of the Mexican Society of Radiological Safety C.A

    International Nuclear Information System (INIS)

    Martinez C, T.M.C.; Garcia, L.M.

    1996-01-01

    The basic safety standards have the purpose to establish the fundamental requirements in order to protect vs. ionizing radiations derived of the risks by exposure to the radiations and to maintain the safety of the radiation sources which can generate such exposure. With base on principles thoroughly accepted, like the established for the ICRP and the IAEA, it pretend to maintain the safety of the several types of radiation sources and as complement for other standards, already established, destined to specific facilities like reactors, irradiators and radioactive waste store, regarding which they are appropriate. (author)

  11. Points for Improvement in Mexican Legislation on Safeguards

    International Nuclear Information System (INIS)

    Maciel Sánchez, S.; Carreño Padilla, A. L.

    2015-01-01

    The main goal of this paper is to underline the specific points needed still to be improved on safeguards in the Mexican legal framework. The problem: Mexico proposed the Tlatelolco Treaty which was before the TNP. So the Mexican legislation on safeguards should to be one of the best around the world, but there are still points to be improved, such as a specific regulation on the topic. Justification: Remembering that the exact sciences need of the law in order to be applied in a desirable way. I mean, the safeguards could be well conceived and well worked from the physics and mathematics point of view, but in order to be followed in any country, it is necessary the right legal framework. Hypothesis: What has Mexico now in its legislation on safeguards and what remains to be done (what is pending in the Mexican legal scope of the safeguards)? Objectives: – To propose legal solutions to correct the weakness of the Mexican legal framework on Safeguards; taking into account my own experience drafting the Mexican regulation on safeguards from 2008 for the Mexican Government in my nuclear law firm “Martínez and Maciel”. – To propose a legal framework on safeguards for Mexico as it is understood by the IAEA. – To update the legal frame work on safeguards in Mexico linking it to the Back end of the spent fuel. (Considering that sooner or later the Mexican Government will have to define its politic on this topic). (author)

  12. General overview of the Mexican energy sector

    International Nuclear Information System (INIS)

    Perez-Jacome, D.

    1999-01-01

    An overview of Mexico's energy sector was presented, with particular focus on the natural gas and electricity sectors. Mexico ranks fifth in oil production, eighth in proven oil reserves, and fourteenth in natural gas reserves. In 1998, the energy sector generated 3.3 per cent of Mexico's gross domestic product (GDP), and oil accounted for 7.5 per cent of total exports. National production of natural gas has been forecasted to grow at a rate of 5.2 per cent annually over the next 10 years. This will be largely due to the increased demand for natural gas to produce electricity. The Mexican government has also taken initiatives to restructure the Mexican energy sector with particular focus on increasing the competitiveness of the electric power industry. Electricity demand is also expected to grow at a rate of 6 per cent annually over the next six years. The objectives of energy reform are to promote more investment from all sectors in order to strengthen the development of the electric power industry and to provide a reliable, high quality service at competitive prices. 9 figs

  13. Mexican registry of pulmonary hypertension: REMEHIP.

    Science.gov (United States)

    Sandoval Zarate, Julio; Jerjes-Sanchez, Carlos; Ramirez-Rivera, Alicia; Zamudio, Tomas Pulido; Gutierrez-Fajardo, Pedro; Elizalde Gonzalez, Jose; Leon, Mario Seoane Garcia De; Gamez, Miguel Beltran; Abril, Francisco Moreno Hoyos; Michel, Rodolfo Parra; Aguilar, Humberto Garcia

    REMEHIP is a prospective, multicentre registry on pulmonary hypertension. The main objective will be to identify the clinical profile, medical care, therapeutic trends and outcomes in adult and pediatric Mexican patients with well-characterized pulmonary hypertension. REMEHIP a multicenter registry began in 2015 with a planned recruitment time of 12 months and a 4-year follow-up. The study population will comprise a longitudinal cohort study, collecting data on patients with prevalent and incident pulmonary hypertension. Will be included patients of age >2 years and diagnosis of pulmonary hypertension by right heart catheterization within Group 1 and Group 4 of the World Health Organization classification. The structure, data collection and data analysis will be based on quality current recommendations for registries. The protocol has been approved by institutional ethics committees in all participant centers. All patients will sign an informed consent form. Currently in Mexico, there is a need of observational registries that include patients with treatment in the everyday clinical practice so the data could be validated and additional information could be obtained versus the one from the clinical trials. In this way, REMEHIP emerges as a link among randomized clinical trials developed by experts and previous Mexican experience. Copyright © 2016 Instituto Nacional de Cardiología Ignacio Chávez. Publicado por Masson Doyma México S.A. All rights reserved.

  14. [Mexican] Private-sector petroleum companies and agents

    International Nuclear Information System (INIS)

    1993-07-01

    An overview is presented of the Mexican petroleum sector. The sector is largely controlled by the state company PEMEX and is not completely open to foreign participation and supply, however the trend towards privatization and open competition, combined with the drive for competitiveness of PEMEX operations in particular, is creating market opportunities for foreign suppliers of petroleum equipment and services. Detailed profiles are provided of 50 Mexican companies and their primary products and services, specific areas of expertise, client base, international experience, interest in Canada, other relevant information, and a contact person. A less detailed list is also provided of additional Mexican contacts, petroleum industry associations and chambers of commerce

  15. Personality traits associated with success in Mexican exporter

    Directory of Open Access Journals (Sweden)

    Olga Leticia Gil Gaytan

    2017-06-01

    Full Text Available The objective of this research is to identify the personality traits associated with success in exporting by Mexican entrepreneurs in the Guadalajara metropolitan area. The main justification for carrying out this study is Mexico’s need to reduce its current dependence on manufacturing exports using foreign investment and increase the exports of Mexican companies. According to this study, there is association between export success and personality traits in successful Mexican exporters. With the spread of these findings, it is expected that both universities and business organizations will consider these results when selecting students for programs related to international venture.

  16. Mixed waste: Proceedings

    International Nuclear Information System (INIS)

    Moghissi, A.A.; Blauvelt, R.K.; Benda, G.A.; Rothermich, N.E.

    1993-01-01

    This volume contains the peer-reviewed and edited versions of papers submitted for presentation a the Second International Mixed Waste Symposium. Following the tradition of the First International Mixed Waste Symposium, these proceedings were prepared in advance of the meeting for distribution to participants. The symposium was organized by the Mixed Waste Committee of the American Society of Mechanical Engineers. The topics discussed at the symposium include: stabilization technologies, alternative treatment technologies, regulatory issues, vitrification technologies, characterization of wastes, thermal technologies, laboratory and analytical issues, waste storage and disposal, organic treatment technologies, waste minimization, packaging and transportation, treatment of mercury contaminated wastes and bioprocessing, and environmental restoration. Individual abstracts are catalogued separately for the data base

  17. Proceedings ICASS 2017

    Science.gov (United States)

    Fu, Qiang; Schaaf, Peter

    2018-07-01

    This special issue of the high impact international peer reviewed journal Applied Surface Science represents the proceedings of the 2nd International Conference on Applied Surface Science ICASS held 12-16 June 2017 in Dalian China. The conference provided a forum for researchers in all areas of applied surface science to present their work. The main topics of the conference are in line with the most popular areas of research reported in Applied Surface Science. Thus, this issue includes current research on the role and use of surfaces in chemical and physical processes, related to catalysis, electrochemistry, surface engineering and functionalization, biointerfaces, semiconductors, 2D-layered materials, surface nanotechnology, energy, new/functional materials and nanotechnology. Also the various techniques and characterization methods will be discussed. Hence, scientific research on the atomic and molecular level of material properties investigated with specific surface analytical techniques and/or computational methods is essential for any further progress in these fields.

  18. Imaging Sciences Workshop Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Candy, J.V.

    1996-11-21

    This report contains the proceedings of the Imaging Sciences Workshop sponsored by C.A.S.LS., the Center for Advanced Signal & Image Sciences. The Center, established primarily to provide a forum where researchers can freely exchange ideas on the signal and image sciences in a comfortable intellectual environment, has grown over the last two years with the opening of a Reference Library (located in Building 272). The Technical Program for the 1996 Workshop include a variety of efforts in the Imaging Sciences including applications in the Microwave Imaging, highlighted by the Micro-Impulse Radar (MIR) system invented at LLNL, as well as other applications in this area. Special sessions organized by various individuals in Speech, Acoustic Ocean Imaging, Radar Ocean Imaging, Ultrasonic Imaging, and Optical Imaging discuss various applica- tions of real world problems. For the more theoretical, sessions on Imaging Algorithms and Computed Tomography were organized as well as for the more pragmatic featuring a session on Imaging Systems.

  19. Mixed waste: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Moghissi, A.A.; Blauvelt, R.K.; Benda, G.A.; Rothermich, N.E. [eds.] [Temple Univ., Philadelphia, PA (United States). Dept. of Environmental Safety and Health

    1993-12-31

    This volume contains the peer-reviewed and edited versions of papers submitted for presentation a the Second International Mixed Waste Symposium. Following the tradition of the First International Mixed Waste Symposium, these proceedings were prepared in advance of the meeting for distribution to participants. The symposium was organized by the Mixed Waste Committee of the American Society of Mechanical Engineers. The topics discussed at the symposium include: stabilization technologies, alternative treatment technologies, regulatory issues, vitrification technologies, characterization of wastes, thermal technologies, laboratory and analytical issues, waste storage and disposal, organic treatment technologies, waste minimization, packaging and transportation, treatment of mercury contaminated wastes and bioprocessing, and environmental restoration. Individual abstracts are catalogued separately for the data base.

  20. Spectral Line Shapes. Proceedings

    International Nuclear Information System (INIS)

    Zoppi, M.; Ulivi, L.

    1997-01-01

    These proceedings represent papers presented at the 13th International Conference on Spectral Line Shapes which was held in Firenze,Italy from June 16-21, 1996. The topics covered a wide range of subjects emphasizing the physical processes associated with the formation of line profiles: high and low density plasma; atoms and molecules in strong laser fields, Dopple-free and ultra-fine spectroscopy; the line shapes generated by the interaction of neutrals, atoms and molecules, where the relavant quantities are single particle properties, and the interaction-induced spectroscopy. There were 131 papers presented at the conference, out of these, 6 have been abstracted for the Energy Science and Technology database

  1. A cross-over in Mexican and Mexican-American fertility rates: Evidence and explanations for an emerging paradox

    Directory of Open Access Journals (Sweden)

    Patrick Heuveline

    2005-03-01

    Full Text Available Against a backdrop of two new developments in the fertility behavior of the Mexican- Origin population in the U.S., the present discussion will update contemporary Mexican-Origin fertility patterns and address several theoretical weaknesses in the current approach to minority group fertility. Data come from six national surveys (three from Mexico and three from the U.S. that cover a twenty-five year period (1975-2000. The findings demonstrate dramatic decreases in the fertility rates in Mexico at the same time that continuous increases have been documented in the fertility rates of third-or-later generation Mexican-Americans in the U.S., particularly at younger ages. These changes necessitate a reexamination of the ubiquitous theory that Mexican pronatalist values are responsible for the high fertility rates found within the Mexican-Origin population in the U.S. Instead, they point to the increasing relevance of framing the fertility behavior of the Mexican-Origin population within a racial stratification perspective that stresses the influence of U.S. social context on fertility behavior. As a step in this direction, the analysis examines fertility patterns within the Mexican-Origin population in the U.S. Special attention is given to the role of nativity/generational status in contributing to within group differences.

  2. The Mexican Revolution and health care or the health of the Mexican Revolution.

    Science.gov (United States)

    Horn, J J

    1985-01-01

    Despite a victorious social revolution, a self-proclaimed "revolutionary" government, and a significant post-war economic growth, Mexico has not achieved a just or equitable social system. The Mexican Revolution led to the emergence of a new bureaucratic class whose "trickle-down" development strategy sacrificed social welfare to capital accumulation. Mexican morbidity and mortality patterns resemble those of more impoverished developing nations without revolutionary experience. The patterns of health care in Mexico reflect inequities and contradictions in the society and economy at large and flow from the erosion of the egalitarian aims of the revolution concomitant with the expansion of capitalism and the concentration of the benefits of "modernization" in the hands of privileged elites. Mexico's health problems are symptomatic of a general socio-economic malaise which questions the legitimacy of the Revolution.

  3. Reproductive habitus, psychosocial health, and birth weight variation in Mexican immigrant and Mexican American women in south Texas.

    Science.gov (United States)

    Fleuriet, K Jill; Sunil, T S

    2015-08-01

    The Latina Paradox, or persistent, unexplained variation in low birth weight rates in recently immigrated Mexican women and the trend toward higher rates in subsequent generations of Mexican American women, is most often attributed to unidentified sociocultural causes. We suggest herein that different disciplinary approaches can be synthesized under the constructs of reproductive habitus and subjective social status to identify influences of sociocultural processes on birth weight. Reproductive habitus are "modes of living the reproductive body, bodily practices, and the creation of new subjects through interactions between people and structures" (Smith-Oka, 2012: 2276). Subjective social status infers comparison of self to others based on community definitions of status or socioeconomic status (Adler 2007). We present results from a prospective study of low-income Mexican immigrant and Mexican American women from south Texas that tested the ability of reproductive habitus and subjective social status to elucidate the Latina Paradox. We hypothesized that reproductive habitus between Mexican immigrant women and Mexican American women inform different subjective social statuses during pregnancy, and different subjective social statuses mediate responses to psychosocial stressors known to correlate with low birth weight. Six hundred thirty-one women were surveyed for psychosocial health, subjective social status, and reproductive histories between 2011 and 2013. Eighty-three women were interviewed between 2012 and 2013 for status during pregnancy, prenatal care practices, and pregnancy narratives and associations. Birth weight was extracted from medical records. Results were mixed. Subjective social status and pregnancy-related anxiety predicted low birth weight in Mexican immigrant but not Mexican American women. Mexican immigrant women had significantly lower subjective social status scores but a distinct reproductive habitus that could explain improved psychosocial

  4. Diabetes is more lethal in Mexicans and Mexican Americans compared to non-Hispanic Whites

    Science.gov (United States)

    Hunt, Kelly J; Gonzalez, Maria Elena; Lopez, Ruy; Haffner, Steve M; Stern, Michael P; Gonzalez-Villalpando, Clicerio

    2012-01-01

    Purpose To examine the mortality risk associated with diabetes in the Mexico City Diabetes Study (MCDS) and the San Antonio Heart Study (SAHS). Methods Prospective cohorts conducted 1990-2007 in MCDS and 1979-2000 in SAHS. Mortality risk was examined using Cox proportional hazard models in 1,402 non-Hispanic whites (NHW), 1,907 U.S.-born Mexican Americans (MA), 444 Mexican-born MA, 2,281 Mexico City residents (MCR) between the ages of 35 and 64. Results Age- and sex-adjusted mortality HRs comparing U.S.-born MA, Mexican-born MA and MCR to NHW were 1.09 (95% CI: 0.86, 1.37), 1.23 (95% CI: 0.86, 1.76) and 0.97 (95% CI: 0.77, 1.23), respectively, in non-diabetic individuals; in contrast, mortality risk varied in diabetic individuals with respective HRs of 1.77 (95% CI: 1.20, 2.61), 1.08 (95% CI: 0.59, 1.97) and 2.27 (95% CI: 1.53, 3.35) (interaction p-value=0.0003). Excluding Mexican-born MA and non-diabetic individuals, controlling for medication use, insulin use, fasting glucose levels and duration of diabetes explained a significant proportion of the mortality differential (HRs relative to NHW were 1.31 (95% CI: 0.87, 1.98) in U.S.-born MA and 1.38 (95% CI: 0.89, 2.12) in MCR). Conclusions This study provides evidence that diabetes is more lethal in U.S.-born MA and MCR than in NHW. PMID:21840730

  5. The Smell of Memories. A Mexican Migrant’s Search for Emotional Sustainability through Mexican Films.

    Directory of Open Access Journals (Sweden)

    Gabriela Coronado

    2011-12-01

    Full Text Available For more than 10 years living as a Mexican migrant, between two countries (Mexico and Australia, two cities (Mexico City and Sydney, and two social worlds (Mexican and multicultural Australian ‘families-friends’, I have been immersed in a systematic process of self observation and self reflection on my life in my country of destination. During this time I have explored my memories of place and their relationship with my emotional experiences, looking for strategies to continue to be connected with my country of origin and my people. In this process I discovered films were especially significant in sustaining me emotionally. I benefited from the memory associations triggered by representations of Mexico in films produced by Mexicans or by filmmakers from other nationalities. By reflecting on my responses to those films, in this paper I explore how representations of their country of origin can impact on migrants’ emotional life. Using autoethnography, examining my own subjectivity as a way to arrive at a deeper grasp of these processes, I analyse the roles played by different senses in the process of recollection and in the emotional effects produced, which come to embody the experience. My particular focus in this article is the sense of smell triggered by complex interactions within the sensorium while watching films, producing associations and feelings through which I re-live my memories and maintain my emotional sustainability.

  6. Opportunities - oil and gas development in the Mexican market

    International Nuclear Information System (INIS)

    1997-01-01

    This review of business opportunities is intended as a guide for Alberta companies who are interested in investing or otherwise participating in the Mexican oil and gas industry. The guide provides a brief summary of Mexico, its political, legal and economic system, a brief review of the Mexican oil and gas industry, environmental legislation, the financial institutions, labour/management relations and overseas trade relations. Opportunities for Alberta firms in the Mexican resources industry are identified. Steps to follow for anyone contemplating business with Pemex, the state-owned oil company, are outlined and sources of assistance available to Alberta companies are reviewed. There are various lists of private consultants, Canadian banks in Mexico, accounting firms, customs brokers, freight forwarders and tips on Canadian and Mexican sources of financing. There is also a summary of commercial regulations between Pemex and its suppliers, and an organization chart of the Exploration and Production Branch of Petroleos Mexicanos. tabs., figs

  7. FastStats: Health of Mexican American Population

    Science.gov (United States)

    ... Submit Button NCHS Home Health of Mexican American Population Recommend on Facebook Tweet Share Compartir Data are ... Source: Summary Health Statistics Tables for the U.S. Population: National Health Interview Survey, 2015, Table P-1c [ ...

  8. Mexican immigration and the port-of-entry school.

    Science.gov (United States)

    Baca, R; Bryan, D; Mclean-bardwell, C; Gomez, F

    1989-01-01

    The results of an immigrant student census in a California port-of-entry school district are used to describe the educational backgrounds of Mexican immigrant students and to distinguish types of Mexican immigrant students by school entry patterns. Interviews with recently arrived Mexican immigrant parents reveal the educational and occupational expectations they hold for their children in the US. The study findings are used as a basis for raising policy questions and generating research issues. The most notable observation from the study is that the children of Mexican immigrants in La Entrada do not migrate once they are in school. Parents may be migrating back and forth between the US and Mexico, but children once in La Entrada do not leave the school to return to school in Mexico. The study suggests that the parents of immigrant students do not know how the US educational system works but they are interested in helping teachers educate their children.

  9. B Physics at the D0 experiment A Mexican review

    International Nuclear Information System (INIS)

    De La Cruz-Burelo, E.

    2010-01-01

    On April of 1992 a Mexican group from Cinvestav officially joined the D0 experiment, one of the two experiments in the Tevatron collider at Fermilab. The seed for this experimental group on high energy physics from Cinvestav was planted in Mexico in some measure by Augusto Garcia, to whom this workshop is in memorial. Augusto's efforts and support to groups dedicated to this area was clear and important. Some of these seeds have given origin to today's established Mexican groups on experimental high energy physics, one example of this is the Mexican group at D0. I present here a short review of some of the D0 results on which the Mexican group has contributed, emphasizing the last decade, which I have witnessed.

  10. United States -- Mexican joint ventures: A case history approach

    Energy Technology Data Exchange (ETDEWEB)

    Moore, N.L.; Chidester, R.J.; Hughes, K.R.; Fowler, R.A.

    1993-03-01

    Because the Mexican government has encouraged investment in Mexico by increasing the percentage of ownership of a Mexican business that a US company can hold, joint ventures are more attractive now than they had been in the past. This study provides preliminary information for US renewable energy companies who are interested in forming a joint venture with a Mexican company. This report is not intended to be a complete reference but does identifies a number of important factors that should be observed when forming a Mexican joint venture: (1)Successful joint ventures achieve the goals of each partner. (2)It is essential that all parties agree to the allocation of responsibilities. (3)Put everything in writing. (4)Research in depth the country or countries in which you are considering doing business.

  11. Theory of elementary particles. Proceedings

    International Nuclear Information System (INIS)

    Luest, D.; Weigt, G.

    1994-03-01

    These proceedings contain most of the invited talks ans short communications presented at the named symposium. These concern developments in field theory in connection with string models, grand unification, and quantum gravity. See hints under the relevant topics. (HSI)

  12. The Food Environment in an Urban Mexican American Community

    OpenAIRE

    Lisabeth, Lynda D; Sánchez, Brisa N; Escobar, James; Hughes, Rebecca; Meurer, William J; Zuniga, Belinda; Garcia, Nelda; Brown, Devin L; Morgenstern, Lewis B

    2010-01-01

    The objective was to determine whether ethnic composition of neighborhoods is associated with number and type of food stores in an urban, Mexican American US community. Data were from a commercial food store data source and the US Census. Multivariate count models were used to test associations with adjustment for neighborhood demographics, income, and commercialization. Neighborhoods at the 75th percentile of percent Mexican American (76%) had nearly four times the number of convenience stor...

  13. Patterns of contraceptive use among Mexican-origin women

    Directory of Open Access Journals (Sweden)

    Kari White

    2013-06-01

    Full Text Available BACKGROUND Mexican women in the United States (US have higher rates of fertility compared to other ethnic groups and women in Mexico. Whether variation in women's access to family planning services or patterns of contraceptive use contributes to this higher fertility has received little attention. OBJECTIVE We explore Mexican women's contraceptive use, taking into account women's place in the reproductive life course. METHODS Using nationally representative samples from the US (National Survey of Family Growth and Mexico (Encuesta National de la Dinámica Demográfica, we compared the parity-specific frequency of contraceptive use and fertility intentions for non-migrant women, foreign-born Mexicans in the US, US-born Mexicans, and whites. RESULTS Mexican women in the US were less likely to use IUDs and more likely to use hormonal contraception than women in Mexico. Female sterilization was the most common method among higher parity women in both the US and Mexico, however, foreign-born Mexicans were less likely to be sterilized, and the least likely to use any permanent contraceptive method. Although foreign-born Mexicans were slightly less likely to report that they did not want more children, differences in method use remained after controlling for women's fertility intentions. CONCLUSIONS At all parities, foreign-born Mexicans used less effective methods. These findings suggest that varying access to family planning services may contribute to variation in women's contraceptive use. COMMENTS Future studies are needed to clarify the extent to which disparities in fertility result from differences in contraceptive access.

  14. Family Structure and Family Processes in Mexican American Families

    OpenAIRE

    Zeiders, Katharine H.; Roosa, Mark W.; Tein, Jenn-Yun

    2011-01-01

    Despite increases in single-parent families among Mexican Americans (MA), few studies have examined the association of family structure and family adjustment. Utilizing a diverse sample of 738 Mexican American families (21.7% single parent), the current study examined differences across family structure on early adolescent outcomes, family functioning, and parent-child relationship variables. Results revealed that early adolescents in single parent families reported greater school misconduct,...

  15. MEXICAN DRUG CARTELS AND TERRORIST ORGANIZATIONS, A NEW ALLIANCE

    Science.gov (United States)

    2016-02-16

    Nevertheless, existing studies provide little evidence to support the claim that a risk of collaboration exists between Mexican cartels and...of Defense (DoD) nor Department of Homeland Security (DHS) have a published definition for cartel. For purposes of this study it is important to note...commodities and real estate. According to National Drug Intelligence Center, Mexican and Colombian cartels launder between $18- $39 billion annually.15

  16. Sanitary and Phytosanitary Measures: The Case of Mexican Avocados

    OpenAIRE

    Bakshi, Nishita

    2003-01-01

    This thesis examines the effects on demand, supply, imports, and prices of partial easing of sanitary and phytosanitary (SPS) barriers to trade in the U.S. market in the case of Mexican avocados. The SPS Agreement plays a role in the avocado market studied here through its implications for negotiations between countries that have not utilized the formal channels of the WTO for resolving disputes. A quarantine in place from 1914 until very recently banned entry of Mexican avocados into the...

  17. Health perceptions of Mexican American women.

    Science.gov (United States)

    Mendelson, Cindy

    2002-07-01

    This article describes the health perceptions of a sample of moderately to highly acculturated Mexican American women. Using an ethnographic design, the author interviewed 13 women to determine their health perceptions. The interviews were guided by the domains of health described in the World Health Organization (WHO) definition of health. Three broad categories of health perceptions were identified: the physical body, the emotional component, and finding balance. With the addition of a spiritual component, the WHO definition was a useful tool for uncovering health perceptions. The process of in-depth ethnographic interviewing provided a contextual view of health in which the complexity of intrafamilial relationships was revealed, as were the importance of spirituality as a coping mechanism and the perception of health as an integrated, holistic experience.

  18. Area selection for conservation of Mexican mammals

    Directory of Open Access Journals (Sweden)

    Vázquez, L. B.

    2009-06-01

    Full Text Available Three sets of priority cells for mammal conservation in Mexico were identified using distributional data. A complementarity approach was implemented through linear integer programming. The minimum set of sites required for the representation of each mammal species varied between 38 (5.4% grid cells for at least one occurrence, 110 (15.6% grid cells for at least three occurrences, and 173 (24.5% grid cells for at least five occurrences. The complementary analyses mainly highlighted three regions of particular concern for mammal conservation in Mexico: (i the trans-Mexican Volcanic Belt and natural provinces of the Pacific Coast, (ii Sierra Madre del Sur and the Highlands of Chiapas, and (iii the northern portion of the Sierra Madre Occidental. The results reported here did not indicate absolute priority locations for conservation activities, but rather identified locations warranting further investigation at finer resolutions more appropriate to such activity

  19. [First Mexican Consensus of Vaccination in Adults].

    Science.gov (United States)

    Gutiérrez-Robledo, Luis Miguel; Caro-López, Elizabeth; Guerrero-Almeida, María de Lourdes; Dehesa-Violante, Margarita; Rodríguez-Noriega, Eduardo; García-Lara, Juan Miguel; Medina-López, Zaira; Báez-Saldaña, Renata; Díaz-López, Elsa; Avila-Fematt, Flor Maria de Guadalupe; Betancourt-Cravioto, Miguel; Garcia-Garcia, Lourdes

    2017-03-01

    For years our efforts have been focused on vaccination during childhood. Today we know that this is not enough to ensure health in the rest of the life. Childhood is as important as any other stage and, therefore, vaccination must be permanent and differentiated, according to our age, throughout life. Introducing a life course perspective in vaccination programs, with emphasis on adult vaccination, particularly in older adults, offers us the opportunity to review the performance of health programs, actions, and services in the field of immunization, as well as strengthening health promotion actions. In this context, the first Mexican Consensus on Adult Vaccination was carried out in a joint effort of the National Institute of Geriatrics, bringing together a group of specialists who worked on three central objectives: establishing vaccination guidelines throughout the life course, with emphasis on new vaccines; defining priority groups according to their risk factors; and contributing to the effort to promote healthy aging.

  20. Religiosity and Migration Aspirations among Mexican Youth.

    Science.gov (United States)

    Hoffman, Steven; Marsiglia, Flavio Francisco; Ayers, Stephanie L

    2015-02-01

    International migration has become an important topic of discussion from a policy and humanitarian perspective. Part of the debate includes a renewed interest in understanding the factors that influence decisions about migration to the US among Mexican youth still residing in their country of origin. The purpose of this study was to advance knowledge specifically about internal and external religiosity and their influence on youths' migration aspirations. The data for this study were collected in 2007 from students enrolled in an alternative high school program located in the state of Guanajuato, Mexico. The findings indicated that as external religiosity increases, the desire to work or live in the USA decreases. Furthermore, as internal religiosity increases, the desire to work or live in the USA and plans to migrate increase. The results are interpreted and discussed in light of previous research on religious and cultural norm adherence.

  1. Mexican geothermal development and the future

    International Nuclear Information System (INIS)

    Serrano, J.M.E.V.

    1998-01-01

    Geothermics in Mexico started in 1954, by drilling the first geothermal well in Pathe, State of Hidalgo, which reached a depth of 237 meters. In 1959 electrical generation from geothermal origin began, with an installed capacity of 3.5 MW. From 1959 to 1994 Mexico increased its installed capacity to 753 MW, by developing three geothermal fields: Cerro Prieto, Los Azufres, and Los Humeros. Currently, 177 wells produce steam at a rate of 36 tons per hour (t/h) each. Comision Federal de Electricidad (CFE, Federal Commission of Electricity) has planned to increase the geothermal-electric installed capacity through construction and installation of several projects. Repowering of operating units and development of new geothermal zones will also allow Mexican geothermal growth

  2. [Characterization of Mexican households with food insecurity].

    Science.gov (United States)

    Mundo-Rosas, Verónica; Méndez-Gómez Humarán, Ignacio; Shamah-Levy, Teresa

    2014-01-01

    To describe the sociodemographic and health characteristics associated with food insecurity (FI) in Mexican households. The study included information about 40 809 households from the National Health and Nutrition Survey 2012. The Latin American and Caribbean Scale Food Safety (ELCSA) was used to categorize households in terms of food insecurity. Classification and regression trees were used to identify the most significant characteristics in households with high prevalence of FI. The characteristics associated with higher prevalence of FI in homes were: lowest quintiles of welfare status, lack of education or walking or moving disability of household head, and not receiving money from social programmes, pension or remittances. Monitoring of the factors that favor the presence of FI is required to detect social groups being excluded from the right to food.

  3. Caloric beverage consumption patterns in Mexican children

    Directory of Open Access Journals (Sweden)

    Rivera Juan A

    2010-10-01

    Full Text Available Abstract Background Mexico has seen a very steep increase in child obesity level. Little is known about caloric beverage intake in this country as well as all other countries outside a few high income countries. This study examines overall patterns and trends in all caloric beverages from two nationally representative surveys from Mexico. Methods The two nationally representative dietary intake surveys (1999 and 2006 from Mexico are used to study caloric beverage intake in 17, 215 children. The volume (ml and caloric energy (kcal contributed by all beverages consumed by the sample subjects were measured. Results are weighted to be nationally representative. Results The trends from the dietary intake surveys showed very large increases in caloric beverages among pre-school and school children. The contribution of whole milk and sugar-sweetened juices was an important finding. Mexican pre-school children consumed 27.8% of their energy from caloric beverages in 2006 and school children consumed 20.7% of their energy from caloric beverages during the same time. The three major categories of beverage intake are whole milk, fruit juice with various sugar and water combinations and carbonated and noncarbonated sugared-beverages. Conclusion The Mexican government, greatly concerned about obesity, has identified the large increase in caloric beverages from whole milk, juices and soft drinks as a key target and is initiating major changes to address this problem. They have already used the data to shift 20 million persons in their welfare and feeding programs from whole to 1.5% fat milk and in a year will shift to nonfat milk. They are using these data to revise school beverage policies and national regulations and taxation policies related to an array of less healthful caloric beverages.

  4. PROFAM expands Mexican family planning clinics.

    Science.gov (United States)

    1983-01-01

    Mexico's private, nonprofit social marketing company, known as PROFAM, intends to expand its family planning clinics to marginal urban areas. The clinics are part of PROFAM's push to diversify social marketing outlets for contraceptive products and other birth control methods. PROFAM expects to establish 3 new clinics, possibly including a pregnancy test laboratory, a small 1-doctor clinic, and a large clinic housing an operating room. 1 clinic will be located outside the Mexico City area, the program's traditional boundaries. The company currently runs 2 small clinics and a pregnancy testing laboratory in Ciudad Netzahualcoyti, a community of 3.5 million on Mexico City's outskirts. PROFAM recently obtaine d government approval to sell condoms in food stores, which should increase distribtuion and sales. Currently, the company sells over 1 million high quality, lubricated condoms each month, accounting for over half of the Mexican market. Distribution covers 85% of the country's drugstore. Program setbacks occurred in 1981, when the Mexican government cancelled PROFAM's sales permits for all contraceptive products except condoms. Cancelled products included an oral contraceptive and 3 vaginal spermicides. These 4 products had provided nearly 100,000 couple years of protection in 1979 and an estimated 120,000 CYP 1980. During 1979 and 1980, condoms provided about 27,000 and 60,000 CYP, respectively. PROFAM had relied heavily on the pill and spermicides because its early studies showed condoms had a negative image in Mexico, due largely to the product's association with extramarital affairs. To counter this, PROFAM launched a widespread, free product sampling program in 1979, along with a continuing educational and advertising drive. Subsequent consumer surveys revealed a marked increase in product acceptance, with PROFAM's condom becoming the most widely known brand available in Mexico.

  5. NIC symposium 2010. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Muenster, Gernot [Muenster Univ. (Germany). Inst. fuer Theoretische Physik 1; Wolf, Dietrich [Duisburg-Essen Univ., Duisburg (Germany). Fakultaet fuer Physik; Kremer, Manfred (eds.) [Forschungszentrum Juelich GmbH (DE). Juelich Supercomputing Centre (JSC)

    2012-06-21

    The fifth NIC-Symposium gave an overview of the activities of the John von Neumann Institute for Computing (NIC) and of the results obtained in the last two years by research groups supported by the NIC. The large recent progress in supercomputing is highlighted by the fact that the newly installed Blue Gene/P system in Juelich - with a peak performance of 1 Petaflop/s - currently ranks number four in the TOP500 list. This development opens new dimensions in simulation science for researchers in Germany and Europe. NIC - a joint foundation of Forschungszentrum Juelich, Deutsches Elektronen-Synchrotron (DESY) and Gesellschaft fuer Schwerionenforschung (GSI) - supports with its members' supercomputer facilities about 130 research groups at universities and national labs working on computer simulations in various fields of science. Fifteen invited lectures covered selected topics in the following fields: Astrophysics Biophysics Chemistry Elementary Particle Physics Condensed Matter Materials Science Soft Matter Science Environmental Research Hydrodynamics and turbulence Plasma Physics Computer Science The talks are intended to inform a broad audience of scientists and the interested public about the research activities at NIC. The proceedings of the symposium cover projects that have been supported by the IBM supercomputers JUMP and IBM Blue Gene/P in Juelich and the APE topical computer at DESY-Zeuthen in an even wider range than the lectures.

  6. NIC symposium 2010. Proceedings

    International Nuclear Information System (INIS)

    Muenster, Gernot

    2012-01-01

    The fifth NIC-Symposium gave an overview of the activities of the John von Neumann Institute for Computing (NIC) and of the results obtained in the last two years by research groups supported by the NIC. The large recent progress in supercomputing is highlighted by the fact that the newly installed Blue Gene/P system in Juelich - with a peak performance of 1 Petaflop/s - currently ranks number four in the TOP500 list. This development opens new dimensions in simulation science for researchers in Germany and Europe. NIC - a joint foundation of Forschungszentrum Juelich, Deutsches Elektronen-Synchrotron (DESY) and Gesellschaft fuer Schwerionenforschung (GSI) - supports with its members' supercomputer facilities about 130 research groups at universities and national labs working on computer simulations in various fields of science. Fifteen invited lectures covered selected topics in the following fields: Astrophysics Biophysics Chemistry Elementary Particle Physics Condensed Matter Materials Science Soft Matter Science Environmental Research Hydrodynamics and turbulence Plasma Physics Computer Science The talks are intended to inform a broad audience of scientists and the interested public about the research activities at NIC. The proceedings of the symposium cover projects that have been supported by the IBM supercomputers JUMP and IBM Blue Gene/P in Juelich and the APE topical computer at DESY-Zeuthen in an even wider range than the lectures.

  7. NIC symposium 2010. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Muenster, Gernot [Muenster Univ. (Germany). Inst. fuer Theoretische Physik 1; Wolf, Dietrich [Duisburg-Essen Univ., Duisburg (Germany). Fakultaet fuer Physik; Kremer, Manfred [Forschungszentrum Juelich GmbH (DE). Juelich Supercomputing Centre (JSC)

    2012-06-21

    The fifth NIC-Symposium gave an overview of the activities of the John von Neumann Institute for Computing (NIC) and of the results obtained in the last two years by research groups supported by the NIC. The large recent progress in supercomputing is highlighted by the fact that the newly installed Blue Gene/P system in Juelich - with a peak performance of 1 Petaflop/s - currently ranks number four in the TOP500 list. This development opens new dimensions in simulation science for researchers in Germany and Europe. NIC - a joint foundation of Forschungszentrum Juelich, Deutsches Elektronen-Synchrotron (DESY) and Gesellschaft fuer Schwerionenforschung (GSI) - supports with its members' supercomputer facilities about 130 research groups at universities and national labs working on computer simulations in various fields of science. Fifteen invited lectures covered selected topics in the following fields: Astrophysics Biophysics Chemistry Elementary Particle Physics Condensed Matter Materials Science Soft Matter Science Environmental Research Hydrodynamics and turbulence Plasma Physics Computer Science The talks are intended to inform a broad audience of scientists and the interested public about the research activities at NIC. The proceedings of the symposium cover projects that have been supported by the IBM supercomputers JUMP and IBM Blue Gene/P in Juelich and the APE topical computer at DESY-Zeuthen in an even wider range than the lectures.

  8. Uranium hexafluoride handling. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    1991-12-31

    The United States Department of Energy, Oak Ridge Field Office, and Martin Marietta Energy Systems, Inc., are co-sponsoring this Second International Conference on Uranium Hexafluoride Handling. The conference is offered as a forum for the exchange of information and concepts regarding the technical and regulatory issues and the safety aspects which relate to the handling of uranium hexafluoride. Through the papers presented here, we attempt not only to share technological advances and lessons learned, but also to demonstrate that we are concerned about the health and safety of our workers and the public, and are good stewards of the environment in which we all work and live. These proceedings are a compilation of the work of many experts in that phase of world-wide industry which comprises the nuclear fuel cycle. Their experience spans the entire range over which uranium hexafluoride is involved in the fuel cycle, from the production of UF{sub 6} from the naturally-occurring oxide to its re-conversion to oxide for reactor fuels. The papers furnish insights into the chemical, physical, and nuclear properties of uranium hexafluoride as they influence its transport, storage, and the design and operation of plant-scale facilities for production, processing, and conversion to oxide. The papers demonstrate, in an industry often cited for its excellent safety record, continuing efforts to further improve safety in all areas of handling uranium hexafluoride. Selected papers were processed separately for inclusion in the Energy Science and Technology Database.

  9. LHC Nobel Symposium Proceedings

    Science.gov (United States)

    Ekelöf, Tord

    2013-12-01

    puzzlement. The apparent absence of hints in the LHC experimental data of new phenomena that could relate to dark matter, dark energy, the dominance of matter over antimatter in the Universe, the unification of the strong and the electroweak interactions and their further unification with gravity left the Symposium with no guidance as to how to answer the question: what next? And in experimental fundamental science it is not the confirmation of already established theories that thrills the most; it is the appearance of the unexpected that creates the greatest excitement. However, the LHC is only at the beginning of its voyage into the uncharted territories of higher energies and smaller dimensions that it was built for, so the possibilities for unexpected discoveries are only starting to be explored. The LHC will start up again in 2015 with nearly twice its previous energy and with increased luminosity—new discoveries might then appear sooner than we even dare hope for! The LHC Nobel Symposium was attended by about 60 invited participants and lasted four days. The program was divided into seven sessions; QCD and Heavy Ion Physics, B Physics, Electroweak Physics, The Higgs Boson, Connections to Neutrino Physics and Astroparticle Physics, Beyond the Standard Model and Forward Look. There were 27 plenary invited talks given by participants, each followed by lively discussions. All but one of the speakers have submitted write-ups of their talks for these proceedings. We are hopeful that the remaining talk will be published in a forthcoming issue of Physica Scripta . I am gratified that Professor Roland Allen has agreed to write a paper on the essence of the Higgs boson discovery to be published in Physica Scripta , intended for undergraduate students and educated physicists, regardless of their field of research. I wish to express my deep gratitude to all Speakers and Participants in the Symposium, to the Members of the Local and International Organizing Committees, to the

  10. LA PRUEBA DOCUMENTADA EN EL NUEVO SISTEMA DE JUSTICIA PENAL MEXICANO Documented proof in the new Mexican criminal justice system

    Directory of Open Access Journals (Sweden)

    Benavente Chorres Hesbert

    2010-01-01

    Full Text Available El presente estudio analiza los supuestos de prueba documentada regulados en aquellos códigos de las entidades federativas mexicanas que han adecuado el proceso penal al sistema acusatorio con tendencia adversarial. En ese sentido, se entiende por prueba documentada aquellas diligencias, principalmente declaraciones, realizadas durante la etapa de investigación que la ley otorga valor probatorio al no poder asistir el órgano de prueba a la audiencia del juicio oral por razones ajenas a su voluntad.This study analyzes the cases of the documented proof in those codes regulated the Mexican states that have appropriate criminal proceedings prone to adversarial system. In that sense, it is understood by those measures documented evidence, primarily statements made during the investigation stage that the law gives the probative value could not attend the court hearing to test the trial for reasons beyond their control.

  11. Weight status of Mexican immigrant women: a comparison with women in Mexico and with US-born Mexican American women.

    Science.gov (United States)

    Guendelman, Sylvia D; Ritterman-Weintraub, Miranda L; Fernald, Lia C H; Kaufer-Horwitz, Martha

    2013-09-01

    We assessed the association between birthplace, residence, or years in the United States and actual weight (body mass index), perceived weight accuracy, or provider screens for overweight or obesity among Mexican immigrant women. We used linked data from Health and Nutrition Examination Survey waves 2001-2006 and 2006 National Mexican Health and Nutrition Survey to compare 513 immigrants with 9527 women in Mexico and 342 US-born Mexican American women. Immigrants were more likely than women in Mexico to be obese and to perceive themselves as overweight or obese after adjustment for confounders. Recent immigrants had similar weight-related outcomes as women in Mexico. Immigrants were less likely to be obese than were US-born Mexican Americans. Within the overweight or obese population, reported provider screens were higher among immigrants than among women in Mexico, but lower than among US-born Mexican Americans. US residency of at least 5 years but less than 20 years and reporting insufficient provider screens elevated obesity risk. Mexican-origin women in the United States and Mexico are at risk for overweight and obesity. We found no evidence of a "healthy immigrant" effect.

  12. Obesity and central adiposity in Mexican adults: results from the Mexican National Health and Nutrition Survey 2006.

    Science.gov (United States)

    Barquera, Simón; Campos-Nonato, Ismael; Hernández-Barrera, Lucía; Flores, Mario; Durazo-Arvizu, Ramón; Kanter, Rebecca; Rivera, Juan A

    2009-01-01

    To estimate the prevalence of overweight, obesity and central adiposity in Mexico, and to explore trends compared to the previous Mexican National Health Survey (ENSA 2000) and to Mexican-Americans. The Mexican National Health and Nutrition Survey 2006 (ENSANUT 2006) was used to describe overweight, obesity and central adiposity. Trends over time were assessed using the ENSA 2000 and by comparing the ENSANUT 2006 results to those of Mexican-Americans using the United States National Health and Nutrition Examination Survey (NHANES) 1999-2000 and 2005-2006. A total of 33023 adults > 20 years old were included; 39.7% were found to be overweight and 29.9% were found to be obese; 75.9% of all adults had abdominal obesity. In Mexico between 2000 and 2006, the combined prevalence of overweight and obesity in adults increased approximately 12%. Mexican-Americans showed a higher prevalence of morbid obesity compared to native Mexicans. Mexico has experienced a rapid increase in the number of adults who have experienced excess weight gain between the years 2000 and 2006.

  13. Familism, machismo and child rearing practices among Mexican Americans.

    Science.gov (United States)

    Tamez, E G

    1981-09-01

    Mexican Americans form the 2nd largest minority group in the US. Fertility is 50% higher than in any other ethnic group. Income levels are inordinately low. In 1970, 42% of Mexican Americans were indigent, making approxiamtely 4200 annually. The Mexican American poor can be categorized into newly arrived aliens or 2nd or 3rd generation American citizens. In the 1st instance, the couple is young and English is not spoken. 2nd or 3rd generation Mexican Americans speak English. The persistent socioeconomic status of the Mexican American relates directly to the level of education. 52% of all Mexican Americans do not finish high school. Paz and Remos described the Mexican in terms of Adler's inferiority model. Murillo stated that to an individual, the family--whether nuclear or extended--is the center of life. The inherent responsibility is that the individual behave properly lest the family be disgraced. The family provides emotional and material security. Familism was seen as a deterrant to utilization of health care services, although some studies claim opposing views. Familism and occupational stability related positively to seeking medical care when ill. Hayden believed that supreme male dominance, individualism, pride, wife beating, aversion to contraceptives, and other characteristics were attributable to machismo. A predominant pattern in Mexican American culture is that of elders' ordering young men and women to establish obedience and male dominance. The husband represents authority and the wife-mother maintains a role of complete devotion to her husband and children. Role differentiation is taught implicitly and explicitly from infancy. Studies on the psychological differences between the sexes indicated that females were oppressed and had lower self esteem than males. 18-24 year old Mexican Americans are becoming less insistent upon strict separation of sex roles and are beginning to reject the traditional Mexican notion of masculine superiority. The word

  14. EDITORIAL: XIII Mexican Workshop on Particles and Fields

    Science.gov (United States)

    Barranco, Juan; Contreras, Guillermo; Delepine, David; Napsuciale, Mauro

    2012-08-01

    Juan Barranco Physics Department, Guanajuato University, Loma del Bosque 103, col. Loma del Campestre, 37150, Leon (Mexico) jbarranc@fisica.ugto.mx Guillermo Contreras Departamento de Fisica Aplicada Centro de Investigacion y de Estudios Avanzados del Instituto Politecnico Nacional, Merida (Mexico) jgcn@mda.cinvestav.mx David Delepine Physics Department, Guanajuato University, Loma del Bosque 103, col. Loma del Campestre, 37150, Leon (Mexico) delepine@fisica.ugto.mx Mauro Napsuciale Physics Department, Guanajuato University, Loma del Bosque 103, col. Loma del Campestre, 37150, Leon (Mexico) mauro@fisica.ugto.mx The XIII Mexican Workshop on Particles and Fields (MWPF) took place from 20-26 October 2011, in the city of León, Guanajuato, México. This is a biennial meeting organized by the Division of Particles and Fields of the Mexican Physical Society designed to gather specialists in different areas of high energy physics to discuss the latest developments in the field. The thirteenth edition of this meeting was hosted by the Department of Cultural Studies of Guanajuato University in a nice environment dedicated to the Arts and Culture. The XIII MWPF was organized by three working groups who organized the corresponding sessions around three topics. The first one was Strings, Cosmology, Astroparticles and Physics Beyond the Standard Model. In this category we included: Cosmic Rays, Gamma Ray Bursts, Physics Beyond the Standard Model (theory and experimental searches), Strings and Cosmology. The working group for this topic was formed by Arnulfo Zepeda, Oscar Loaiza, Axel de la Macorra and Myriam Mondragón. The second topic was Hadronic Matter which included Perturbative QCD, Jets and Diffractive Physics, Hadronic Structure, Soft QCD, Hadron Spectroscopy, Heavy Ion Collisions and Soft Physics at Hadron Colliders, Lattice Results and Instrumentation. The working group for this topic was integrated by Wolfgang Bietenholz and Mariana Kirchbach. The third topic was

  15. Alternative Energy Workshop Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Gardner, J. [Dovetail Consulting Inc., Vancouver, BC (Canada)

    2001-07-01

    This conference brought together individuals and representatives from businesses and governments to discuss renewable energy opportunities and barriers in British Columbia regarding the development of low-impact, renewable energy production in the province. Another objective was to identify potential policy initiatives to encourage broader production. Barriers were defined as being market failures which result in sub-optimal allocation of resources by prohibiting the installation of renewable energy technologies (RET) for a particular application or by causing an economical RET application to become uneconomic. The three main categories of barriers were described as being information barriers, financial barriers and institutional barriers. Barriers can be met at various stages of a RET project, including preconception, feasibility studies, design, construction and operation. Some of the barriers that were highlighted during the presentations were: (1) a lack of access to market, (2) lack of access to capital, (3) playing field not level, (4) no renewable energy provincial strategy, (5) lack of public education, and (6) externalities not accounted for in the rate structure. The Green Energy Program at BC Hydro was also discussed with reference to the utility's action plan which includes green and eco-efficient energy, greenhouse gas reductions, hydrogen, eco-efficient improvements to existing generation and transmission, defining a green energy market, a new resource plan, and various Power Smart programs. Some other topics that were raised during the conference were the need for priority policy tools to encourage broader renewable energy production. Recommendations for tools for change were included with these proceedings.

  16. Village Power `97. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Cardinal, J.; Flowers, L.; Taylor, R.; Weingart, J. [eds.

    1997-09-01

    It is estimated that two billion people live without electricity and its services. In addition, there is a sizable number of rural villages that have limited electrical service, with either part-day operation by diesel gen-sets or partial electrification (local school or community center and several nearby houses). For many villages connected to the grid, power is often sporadically available and of poor quality. The U.S. National Renewable Energy Laboratory (NREL) in Golden, Colorado, has initiated a program to address these potential electricity opportunities in rural villages through the application of renewable energy (RE) technologies. The objective of this program is to develop and implement applications that demonstrate the technical performance, economic competitiveness, operational viability, and environmental benefits of renewable rural electric solutions, compared to the conventional options of line extension and isolated diesel mini-grids. These four attributes foster sustainability; therefore, the program is entitled Renewables for Sustainable Village Power (RSVP). The RSVP program is a multi-disciplinary, multi-technology, multi-application program composed of six key activities, including village application development, computer model development, systems analysis, pilot project development, technical assistance, and an Internet-based village power project database. The current program emphasizes wind, photovoltaics (PV), and their hybrids with diesel gen-sets. NREL`s RSVP team is currently involved in rural electricity projects in thirteen countries, with U.S., foreign, and internationally based agencies and institutions. This document contains reports presented at the Proceedings of Village Power, 1997. Individual projects have been processed separately for the United States Department of Energy databases.

  17. Georeferenced Population Datasets of Mexico (GEO-MEX): Raster Based GIS Coverage of Mexican Population

    Data.gov (United States)

    National Aeronautics and Space Administration — The Raster Based GIS Coverage of Mexican Population is a gridded coverage (1 x 1 km) of Mexican population. The data were converted from vector into raster. The...

  18. Long-term surveillance plan for the Mexican Hat disposal site Mexican Hat, Utah

    International Nuclear Information System (INIS)

    1997-05-01

    This long-term surveillance plan (LTSP) describes the U.S. Department of Energy's (DOE) long-term care program for the Uranium Mill Tailings Remedial Action (UMTRA) Project Mexican Hat, Utah, disposal site. The U.S. Nuclear Regulatory Commission (NRC) has developed regulations for the issuance of a general license for the custody and long-term care of UMTRA Project disposal sites in 10 CFR Part 40. The purpose of this general license is to ensure that the UMTRA Project disposal sites will be cared for in a manner that protects the public health and safety and the environment. Before each disposal site is licensed, the NRC requires the DOE to submit a site-specific LTSP. The DOE prepared this LTSP to meet this requirement for the Mexican Hat disposal site. The general license becomes effective when the NRC concurs with the DOE's determination of completion of remedial action for the disposal site and the NRC formally accepts this LTSP. This LTSP describes the long-term surveillance program the DOE will implement to ensure that the Mexican Hat disposal site performs as designed. The program is based on two distinct types of activities: (1) site inspections to identify potential threats to disposal cell integrity, and (2) monitoring of selected seeps to observe changes in flow rates and water quality. The LTSP is based on the UMTRA Project long-term surveillance program guidance and meets the requirements of 10 CFR section 40.27(b) and 40 CFR section 192.03. 18 refs., 6 figs., 1 tab

  19. Long-term surveillance plan for the Mexican Hat disposal site, Mexican Hat, Utah

    International Nuclear Information System (INIS)

    1996-01-01

    This plan describes the long-term surveillance activities for the Uranium Mill Tailings Remedial Action (UMTRA) Project disposal site at Mexican Hat, Utah. The US Department of Energy (DOE) will carry out these activities to ensure that the disposal site continues to function as designed. This long-term surveillance plan (LTSP) was prepared as a requirement for acceptance under the US Nuclear Regulatory Commission (NRC) general license for custody and long-term care of residual radioactive material (RRM). This LTSPC documents the land ownership interests and details how the long-term care of the disposal site will be accomplished

  20. Deconstructive humour: subverting Mexican and Chicano stereotypes in ‘Un Día Sin Mexicanos’

    OpenAIRE

    Barrow, Sarah

    2012-01-01

    a long time, US cinema developed unshakeable stereotypes of Mexican ‘otherness’, with characters of Mexican cultural and ethnic heritage stigmatised as criminals or as sensual objects of desire. Filmmakers in Mexico, meanwhile, treated Mexican Americans as misfits who belonged nowhere, or ignored them and their complex experience completely. The emergence of a distinct ‘Chicano cinema’ in the 1960s allowed for the development of a more powerful set of images of Mexican Americans, exploiting t...

  1. Dictionaries of Mexican Sexual Slang for NLP

    Directory of Open Access Journals (Sweden)

    Roberto Villarejo-Martínez

    2018-04-01

    Full Text Available Abstract: In this paper the creation of two relevant resources for the double entendre and humour recognition problem in Mexican Spanish is described: a morphological dictionary and a semantic dictionary. These were created from two sources: a corpus of albures (drawn from “Antología del albur” book and a Mexican slang dictionary (“El chilangonario”. The morphological dictionary consists of 410 forms of words that corresponds to 350 lemmas. The semantic dictionary consists of 27 synsets that are associated to lemmas of morphological dictionary. Since both resources are based on Freeling library, they are easy to implement for tasks in Natural Language Processing. The motivation for this work comes from the need to address problems such as double entendre and computational humour. The usefulness of these disciplines has been discussed many times and it has been shown that they have a direct impact on user interfaces and, mainly, in human-computer interaction. This work aims to promote that the scientific community generates more resources about informal language in Spanish and other languages.  Spanish Abstract: En este artículo se describe la creación de dos recursos relevantes para el reconocimiento del doble sentido y el humor en el español mexicano: un diccionario morfológico y un diccionario semántico. Éstos fueron creados a partir de dos fuentes: un corpus de albures (extraídos del libro "Antología del albur" y un diccionario de argot mexicano ("El chilangonario". El diccionario morfológico consiste en 410 formas de palabras que corresponden a 350 lemas. El diccionario semántico consiste en 27 synsets que están asociados a lemas del diccionario morfológico. Puesto que ambos recursos están basados en la biblioteca Freeling, son fáciles de implementar en tareas de Procesamiento del Lenguaje Natural. La motivación de este trabajo proviene de la necesidad de abordar problemas como el doble sentido y el humor

  2. Communication Interface for Mexican Spanish Dysarthric Speakers

    Directory of Open Access Journals (Sweden)

    Gladys Bonilla-Enriquez

    2012-03-01

    Full Text Available La disartria es una discapacidad motora del habla caracterizada por debilidad o poca coordinación de los músculos del habla. Esta condición puede ser causada por un infarto, parálisis cerebral, o por una lesión severa en el cerebro. Para mexicanos con esta condición hay muy pocas, si es que hay alguna, tecnologías de asistencia para mejorar sus habilidades sociales de interacción. En este artículo presentamos nuestros avances hacia el desarrollo de una interfazde comunicación para hablantes con disartria cuya lengua materna sea el español mexicano. La metodología propuesta depende de (1 diseño especial de un corpus de entrenamiento con voz normal y recursos limitados, (2 adaptación de usuario estándar, y (3 control de la perplejidad del modelo de lenguaje para lograr alta precisión en el Reconocimiento Automático del Habla (RAH. La interfaz permite al usuario y terapéuta el realizar actividades como adaptación dinámica de usuario, adaptación de vocabulario, y síntesis de texto a voz. Pruebas en vivo fueron realizadas con un usuario con disartria leve, logrando precisiones de 93%-95% para habla espontánea.Dysarthria is a motor speech disorder due to weakness or poor coordination of the speechmuscles. This condition can be caused by a stroke, cerebral palsy, or by a traumatic braininjury. For Mexican people with this condition there are few, if any, assistive technologies to improve their social interaction skills. In this paper we present our advances towards the development of a communication interface for dysarthric speakers whose native language is Mexican Spanish. We propose a methodology that relies on (1 special design of a training normal-speech corpus with limited resources, (2 standard speaker adaptation, and (3 control of language model perplexity, to achieve high Automatic Speech Recognition (ASR accuracy. The interface allows the user and therapist to perform tasks such as dynamic speaker adaptation, vocabulary

  3. The Mexican Health Paradox: Expanding the Explanatory Power of the Acculturation Construct

    Science.gov (United States)

    Horevitz, Elizabeth; Organista, Kurt C.

    2013-01-01

    The Mexican health paradox refers to initially favorable health and mental health outcomes among recent Mexican immigrants to the United States. The subsequent rapid decline in Mexican health outcomes has been attributed to the process of acculturation to U.S. culture. However, the construct of acculturation has come under significant criticism…

  4. Contact with the Dead, Religion, and Death Anxiety among Older Mexican Americans

    Science.gov (United States)

    Krause, Neal; Bastida, Elena

    2012-01-01

    The purpose of this study is to see if contact with the dead is associated with lower death anxiety among older Mexican Americans. The data come from a nationwide survey of older Mexican Americans (N = 1,005). The study model specifies that (a) older Mexican Americans who have experienced contact with the dead are more likely to see the…

  5. Contemporary Fertility Patterns and First-Birth Timing among Mexican-Origin Women

    Science.gov (United States)

    Batson, Christie D.

    2013-01-01

    This article examines first-birth timing among Mexican women in the United States over two birth cohorts. Currently, Mexican women are one of a small group that maintains above-replacement fertility in the United States, contributing to both Mexican population growth and overall national population growth. Yet, the fertility timing of Mexican…

  6. "American" Abjection: "Chicanos," Gangs, and Mexican/Migrant Transnationality in Chicago

    Science.gov (United States)

    De Genova, Nicholas

    2008-01-01

    Crime and street violence often evoke racialized discourses about urban space. In this ethnographic research in Chicago, however, the disdain that many Mexican migrants articulated about street gangs principally concerned issues "internal" to the Mexican/Chicano community, notably a profound ambivalence about U.S.-born Mexicans and a…

  7. Parents' Promotion of Psychological Autonomy, Psychological Control, and Mexican-American Adolescents' Adjustment

    Science.gov (United States)

    Sher-Censor, Efrat; Parke, Ross D.; Coltrane, Scott

    2011-01-01

    Mexican-American adolescents are at an elevated risk for adjustment difficulties. In an effort to identify parenting practices that can affect the adjustment of Mexican-American youth, the current study examined parents' promotion of psychological autonomy and parents' psychological control as perceived by Mexican-American early adolescents, and…

  8. Positive pregnancy outcomes in Mexican immigrants: what can we learn?

    Science.gov (United States)

    Page, Robin L

    2004-01-01

    To provide an integrated review of the literature of potential explanations for better than expected pregnancy outcomes in Mexican immigrants, focusing on socioeconomics, social support, desirability of pregnancy, nutrition, substance use, religion, acculturation, and prenatal care. Computerized searches of MEDLINE and CINAHL databases, as well as reference lists from published articles on low birth weight and prematurity in immigrants and acculturation in immigrants from January 1989 to December 2002. Search terms were Mexican immigrant women, childbearing, and pregnancy outcome, and only English-language articles were reviewed. Literature was selected from refereed publications in the areas of nursing, medicine, public health, family, and sociology. Data were extracted using keywords pertinent to pregnancy outcome in Mexican immigrants. Despite having many of the risk factors for poor pregnancy outcomes, Mexican immigrants have superior birth outcomes when compared to U.S.-born women. Social support, familism, healthy diet, limited use of cigarettes and alcohol, and religion may play a role in improved outcomes. The superior outcomes diminish with the process of acculturation as the individual adapts to her new culture. Low birth weight and prematurity are public health concerns in the United States. Through further study of the factors that lead to superior birth outcomes among Mexican immigrant women, rates of low birth weight and prematurity in the United States may be reduced.

  9. Mobility and International Collaboration: Case of the Mexican Scientific Diaspora.

    Directory of Open Access Journals (Sweden)

    Rafael Marmolejo-Leyva

    Full Text Available We use a data set of Mexican researchers working abroad that are included in the Mexican National System of Researchers (SNI. Our diaspora sample includes 479 researchers, most of them holding postdoctoral positions in mainly seven countries: USA, Great Britain, Germany, France, Spain, Canada and Brazil. Their research output and impact is explored in order to determine their patterns of production, mobility and scientific collaboration as compared with previous studies of the SNI researchers in the periods 1991-2001 and 2003-2009. Our findings confirm that mobility has a strong impact on their international scientific collaboration. We found no substantial influence among the researchers that got their PhD degrees abroad from those trained in Mexican universities. There are significant differences among the areas of knowledge studied: biological sciences, physics and engineering have better production and impact rates than mathematics, geosciences, medicine, agrosciences, chemistry, social sciences and humanities. We found a slight gender difference in research production but Mexican female scientists are underrepresented in our diaspora sample. These findings would have policy implications for the recently established program that will open new academic positions for young Mexican scientists.

  10. Mobility and International Collaboration: Case of the Mexican Scientific Diaspora.

    Science.gov (United States)

    Marmolejo-Leyva, Rafael; Perez-Angon, Miguel Angel; Russell, Jane M

    2015-01-01

    We use a data set of Mexican researchers working abroad that are included in the Mexican National System of Researchers (SNI). Our diaspora sample includes 479 researchers, most of them holding postdoctoral positions in mainly seven countries: USA, Great Britain, Germany, France, Spain, Canada and Brazil. Their research output and impact is explored in order to determine their patterns of production, mobility and scientific collaboration as compared with previous studies of the SNI researchers in the periods 1991-2001 and 2003-2009. Our findings confirm that mobility has a strong impact on their international scientific collaboration. We found no substantial influence among the researchers that got their PhD degrees abroad from those trained in Mexican universities. There are significant differences among the areas of knowledge studied: biological sciences, physics and engineering have better production and impact rates than mathematics, geosciences, medicine, agrosciences, chemistry, social sciences and humanities. We found a slight gender difference in research production but Mexican female scientists are underrepresented in our diaspora sample. These findings would have policy implications for the recently established program that will open new academic positions for young Mexican scientists.

  11. The Mexican mesozoic uranium province: its distribution and metallogeny

    International Nuclear Information System (INIS)

    Bazan B, S.

    1981-01-01

    The distribution of uranium scattered in sedimentary terrains of the continental jurassic such as those found in the Tlaxiaco-Guerrero Basin encourage the outlook for uncovering extensive new deposits of strato-bound uranium belonging to the Mexican mesozoic in other structurally similar intercratonic basins. Stratographic and paleographic structural references define the simultaneous evolution of five sedimentary basins during the Mexican geotechtonic cycle: 1. the Tlaxiaco-Guerrero basin, 2. the Huayacocotla basin, 3. the Gulf of Sabinas basin, 4. the Chihuahua basin and 5. the Sonora basin. From the various lithostratographic formations in them we favourably infer the presence of intermountainous mesozoic concentrations of uranium sediments leached from crystalline precambric packets and from nevadian plutonites and volcanic rocks. During the metallogeny process described under the techtonic evolution of the Mexican structural belt, the presence is established of extensive terciary hydrothermal uranium deposits in the districts of Aldama, Chihuahua; Coneto-El Rodeo, Durango; Vizarron de Montes, Queretaro; Tlaucingo, Puebla; Los Amoles, Sonora; El Picacho, Sonora; Amalia Margarita, Coahuila; etc., scattered in sandstones and sinters of the continental mesozoic and shifted during the postorogenic phase of the Mexican geotectonic cycle. The extensive mesozoic province defined within the Mexican territory favourable to large deposits of uranium, scattered and strato-bound in triassic, jurassic and cretaceous sandstone and sinters, could resolve future demands for energetics within a modified philosophy and resourceful policy of regional mining. (author)

  12. The North American Free Trade Agreement (NAFTA) and Mexican nursing.

    Science.gov (United States)

    Squires, Allison

    2011-03-01

    In the context of nurse migration, experts view trade agreements as either vehicles for facilitating migration or as contributing to brain-drain phenomena. Using a case study design, this study explored the effects of the North American Free Trade Agreement (NAFTA) on the development of Mexican nursing. Drawing results from a general thematic analysis of 48 interviews with Mexican nurses and 410 primary and secondary sources, findings show that NAFTA changed the relationship between the State and Mexican nursing. The changed relationship improved the infrastructure capable of producing and monitoring nursing human resources in Mexico. It did not lead to the mass migration of Mexican nurses to the United States and Canada. At the same time, the economic instability provoked by the peso crisis of 1995 slowed the implementation of planned advances. Subsequent neoliberal reforms decreased nurses' security as workers by minimizing access to full-time positions with benefits, and decreased wages. This article discusses the linkages of these events and the effects on Mexican nurses and the development of the profession. The findings have implications for nursing human resources policy-making and trade in services.

  13. Economic reform, energy, and development: the case of Mexican manufacturing

    International Nuclear Information System (INIS)

    Aguayo, Francisco; Gallagher, K.P.

    2005-01-01

    Given increasing concern over global climate change and national security there is a burgeoning interest in examining the relationship between economic growth and energy use in developed and developing countries. More specifically, decoupling energy use per unit of gross domestic product (GDP) has fast come to be seen as in the interests of national economies and the world as a whole. Recent attention has been paid to the dramatic decreases in the energy intensity of the Chinese economy, which fell by 55% between 1975 and 1995. Do other developing economies follow similar trajectories? This paper examines the energy intensity of the Mexican economy for the period 1988-1998. Although the long-term trend in Mexican energy intensity is rising, the energy intensity of the Mexican economy began to decline in 1988. This paper explores the factors that have contributed to this reduction. Diminishing Mexican energy use per unit of GDP has been driven by significant decreases in industrial energy intensity. We show that these changes have resulted from changes in the composition of Mexican industrial structure, and technological change

  14. 46 CFR 502.61 - Proceedings.

    Science.gov (United States)

    2010-10-01

    ...; Pleadings; Motions; Replies § 502.61 Proceedings. (a) Proceedings are commenced by the filing of a complaint... documents, or that the nature of the matter in issue is such that an oral hearing and cross-examination are...

  15. 4 CFR 28.133 - Stay proceedings.

    Science.gov (United States)

    2010-01-01

    ... GOVERNMENT ACCOUNTABILITY OFFICE GENERAL PROCEDURES GOVERNMENT ACCOUNTABILITY OFFICE PERSONNEL APPEALS BOARD; PROCEDURES APPLICABLE TO CLAIMS CONCERNING EMPLOYMENT PRACTICES AT THE GOVERNMENT ACCOUNTABILITY OFFICE Corrective Action, Disciplinary and Stay Proceedings § 28.133 Stay proceedings. (a) Prior to the effective...

  16. Nuclear Inter Jura '77 Proceedings

    International Nuclear Information System (INIS)

    1977-01-01

    These Proceedings of the Third Congress of the International Nuclear Law Association reproduce the papers presented in their original language with an abstract in English as well as the ensuing discussions. A majority of the papers have been translated into English for the Proceedings. The subjects dealt with respectively concerned contractual aspects of nuclear activities, the impact of nuclear power on the environment and public acceptance, radiological protection, third party liability and insurance, harmonisation of licensing regulations, export of nuclear equipment in relation to the Non-Proliferation Treaty and finally, computerization of nuclear law. (NEA) [fr

  17. [Mexican National Consensus on Assisted Reproduction Treatment].

    Science.gov (United States)

    Kably Ambe, Alberto; López Ortiz, Carlos Salazar; Serviere Zaragoza, Claudio; Velázquez Cornejo, Gerardo; Pérez Peña, Efrain; Santos Haliscack, Roberto; Luna Rojas, Martha; Valerio, Emilio; Santana, Héctor; Gaviño Gaviño, Fernando

    2012-09-01

    It is estimated that 15% of couples living in industrialized countries are infertile, ie have failed to conceive, reproductive age, after 12 months ormore of regular intercourse without contraception. During the past decade has increased the demand for fertility treatments because they believe are moreeffective now. To unify the therapeutic approach and service to patients and set a precedent for a Mexican Official Standard respect and support for the legislation of these procedures. Consensus by technical experts group panel with the participation of 34 national centers accredited for use in assisted reproduction. He organized seven workshops with the following themes: 1) selection of patients for assisted reproduction treatment, 2) schemes controlled ovarian stimulation for assisted reproduction techniques of high complexity, 3) preparation and egg retrieval technique, 4) transferembryo; 5) luteal phase supplementation; 6) indications and techniques of cryopreservation and 7) informed consent. Each table had a coordinator who wrote and presented the findings to the full, it made a number of observations until they reached unanimity of criteria, which are reflected in this document. Patient selection for assisted reproduction techniques is the first step of the process. Proper selection lead to success, in the same way that a bad pick up for failure. In the case of egg donation the most important recommendation is that only one to two embryos transferred in order to reduce multiple pregnancy rates and maintaining high pregnancy rates.

  18. Mexican demand for US natural gas

    International Nuclear Information System (INIS)

    Kanter, M.A.; Kier, P.H.

    1993-09-01

    This study describes the Mexican natural gas industry as it exists today and the factors that have shaped the evolution of the industry in the past or that are expected to influence its progress; it also projects production and use of natural gas and estimates the market for exports of natural gas from the United States to Mexico. The study looks ahead to two periods, a near term (1993--1995) and an intermediate term (1996--2000). The bases for estimates under two scenarios are described. Under the conservative scenario, exports of natural gas from the United States would decrease from the 1992 level of 250 million cubic feet per day (MMCF/d), would return to that level by 1995, and would reach about 980 MMCF/D by 2000. Under the more optimistic scenario, exports would decrease in 1993 and would recover and rise to about 360 MMCF/D in 1995 and to 1,920 MMCF/D in 2000

  19. The Mexican Fruit Fly Eradication Programme

    Energy Technology Data Exchange (ETDEWEB)

    Reyes F, Jesus; Santiago M, Guillermo; Hernandez M, Porfirio [Comision Nacional de Sanidad Agropecuaria (Mexico)

    2000-07-01

    The goal of the Mexican Fruit Fly Eradication Programme is to control, suppress or eradicate from Mexico four species of fruit flies of economic and quarantine importance (Anastrepha ludens Loew, A. obliqua Macquart, A. serpentina Wied. and A. striata Schiner). These pests cause damage amounting to US$710 million per year. In addition to this cost, there are other expenses from pest control actions and the loss of international markets, because fruit importing countries have established stringent quarantine measures to restrict the entry of these pests. For purposes of the programme's implementation, Mexico was divided into three working zones, defined by agro-ecological characteristics, the number of fruit fly species present and the size of fruit growing regions. In addition, a cost:benefit analysis was carried out which indicated that the rate of return, in a 12-year time frame, might be as much as 33:1 in Northern Mexico, and 17:1 in the rest of the country, for an area over 100,000 hectares. Eradication technology involves: 1) surveys of pest populations by trapping and host fruit harvesting to monitor the presence and density of fruit flies, 2) reduction of pest populations applying cultural practices and using selective bait sprays, 3) mass release of sterile flies and augmentative release of parasitoids to eliminate populations and, 4) enforcement of quarantine measures to protect fruit fly free areas.

  20. The Mexican Fruit Fly Eradication Programme

    International Nuclear Information System (INIS)

    Reyes F, Jesus; Santiago M, Guillermo; Hernandez M, Porfirio

    2000-01-01

    The goal of the Mexican Fruit Fly Eradication Programme is to control, suppress or eradicate from Mexico four species of fruit flies of economic and quarantine importance (Anastrepha ludens Loew, A. obliqua Macquart, A. serpentina Wied. and A. striata Schiner). These pests cause damage amounting to US$710 million per year. In addition to this cost, there are other expenses from pest control actions and the loss of international markets, because fruit importing countries have established stringent quarantine measures to restrict the entry of these pests. For purposes of the programme's implementation, Mexico was divided into three working zones, defined by agro-ecological characteristics, the number of fruit fly species present and the size of fruit growing regions. In addition, a cost:benefit analysis was carried out which indicated that the rate of return, in a 12-year time frame, might be as much as 33:1 in Northern Mexico, and 17:1 in the rest of the country, for an area over 100,000 hectares. Eradication technology involves: 1) surveys of pest populations by trapping and host fruit harvesting to monitor the presence and density of fruit flies, 2) reduction of pest populations applying cultural practices and using selective bait sprays, 3) mass release of sterile flies and augmentative release of parasitoids to eliminate populations and, 4) enforcement of quarantine measures to protect fruit fly free areas

  1. The boson and the Mexican hat

    International Nuclear Information System (INIS)

    Cohen-Tannoudji, Gilles; Spiro, Michel

    2013-01-01

    This document contains a brief presentation and the table of contents of a book in which the authors who reports the evolutions of the contemporary astrophysics theories, and the scientific, technological and human adventure of the CERN until the discovery of the Higgs boson by means of the LHC. The Mexican hat is the name given to the mechanism by which the boson reports the origin of the elementary particle masses. The first part reports the boson genealogy: the law of universal gravitation, the relativity and the limits of the rational mechanics, quantum mechanics, and particle physics at the end of the 1960's. The second part addresses the necessary existence of the boson: quantum electrodynamics, from the quark model to quantum chromo-dynamics, from intermediate bosons to the Brout, Englert and Higgs boson, the standard cosmology model. The third part deals with the perspectives opened by the existence and evidence of the boson: the search for physics theory and models beyond standard models

  2. Cobalt 60 cation exchange with mexican clays

    International Nuclear Information System (INIS)

    Nava Galve, R.G.

    1993-01-01

    Mexican clays can be used to remove radioactive elements from contaminated aqueous solutions. Cation exchange experiments were performed with 60 Co radioactive solution. In the present work the effect of contact time on the sorption of Co 2+ was studied. The contact time in hydrated montmorillonite was from 5 to 120 minutes and in dehydrated montmorillonite 5 to 1400 minutes. The Co 2+ uptake value was, in hydrated montmorillonite, between 0.3 to 0.85 m eq/g and in dehydrated montmorillonite, between 0.6 to 1.40 m eq/g. The experiments were done in a pH 5.1 to 5.7 and normal conditions. XRD patterns were used to characterize the samples. The crystallinity was determined by X-ray Diffraction and it was maintained before and after the cation exchange. DTA thermo grams showed the temperatures of the lost humidity and crystallization water. Finally, was observed that dehydrated montmorillonite adsorb more cobalt than hydrated montmorillonite. (Author)

  3. Cytotoxic activity of four Mexican medicinal plants.

    Science.gov (United States)

    Vega-Avila, Elisa; Espejo-Serna, Adolfo; Alarcón-Aguilar, Francisco; Velasco-Lezama, Rodolfo

    2009-01-01

    Ibervillea sonorae Greene, Cucurbita ficifolia Bouché, Tagetes lucida Cav and Justicia spicigera Scheltdd are Mexican native plants used in the treatment of different illnesses. The ethanolic extract of J. spicigera and T. lucida as well as aqueous extracts from I. sonorae, C. ficifolia, T. lucida and J. spicigera were investigated using sulforhodamine B assay. These extracts were assessed using two cell line: T47D (Human Breast cancer) and HeLa (Human cervix cancer). Colchicine was used as the positive control. Data are presented as the dose that inhibited 50% control growth (ED50). All of the assessed extracts were cytotoxic (ED50 < 20 microg/ml) against T47D cell line, meanwhile only the aqueous extract from T. lucida and the ethanolic extract from J. spicigera were cytotoxic to HeLa cell line. Ethanolic extract from J. spicigera presented the best cytotoxic effect. The cytotoxic activity of J. spicigera correlated with one of the popular uses, the treatment of cancer.

  4. Tobacco brand preference among Mexican adolescents.

    Science.gov (United States)

    West, Joshua H; Hall, P Cougar; Page, Randy M; Trinidad, Dennis R; Lindsay, Gordon B

    2012-01-01

    Advertising plays a major role in smoking behavior and forming brand preferences. Additionally, the most advertised tobacco brands have also been the most preferred. Maintaining brand loyalty in Latin America remains a priority for the tobacco industry. The purpose of this study was to explore tobacco brand preference trends from 2003 to 2006, and explore marketing and advertising factors that might be associated with these trends. Data for this study came from Mexican adolescents residing in cities that participated in the Global Youth Tobacco Survey in both 2003 and 2006 and reported smoking either Marlboro or Camel cigarettes in the past 30 days. Respondents reported the brand name of their preferred cigarette during the past 30 days. Multivariate regression analysis was used to determine differences by brand preference and exposure to tobacco marketing and advertising, which was assessed using six items. In 2003, most adolescents preferred Marlboro. By 2006, older boys preferred Camel cigarettes to Marlboro, while girls' preference for Camel was similar to their preference for Marlboro. Adolescents that preferred Camel cigarettes in 2003 also reported greater exposure to tobacco marketing and advertising. Findings indicate that there are ongoing shifts in youth brand preference in Mexico, and that these shifts might be related to marketing and advertising practices. There is an ongoing need for monitoring marketing and advertising practices in an effort to protect adolescents from tobacco company exploits.

  5. Mexican demand for US natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Kanter, M.A.; Kier, P.H.

    1993-09-01

    This study describes the Mexican natural gas industry as it exists today and the factors that have shaped the evolution of the industry in the past or that are expected to influence its progress; it also projects production and use of natural gas and estimates the market for exports of natural gas from the United States to Mexico. The study looks ahead to two periods, a near term (1993--1995) and an intermediate term (1996--2000). The bases for estimates under two scenarios are described. Under the conservative scenario, exports of natural gas from the United States would decrease from the 1992 level of 250 million cubic feet per day (MMCF/d), would return to that level by 1995, and would reach about 980 MMCF/D by 2000. Under the more optimistic scenario, exports would decrease in 1993 and would recover and rise to about 360 MMCF/D in 1995 and to 1,920 MMCF/D in 2000.

  6. 16 CFR 3.2 - Nature of adjudicative proceedings.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Nature of adjudicative proceedings. 3.2... RULES OF PRACTICE FOR ADJUDICATIVE PROCEEDINGS Scope of Rules; Nature of Adjudicative Proceedings § 3.2 Nature of adjudicative proceedings. Adjudicative proceedings are those formal proceedings conducted under...

  7. 17 CFR 12.24 - Parallel proceedings.

    Science.gov (United States)

    2010-04-01

    ...) Definition. For purposes of this section, a parallel proceeding shall include: (1) An arbitration proceeding... the receivership includes the resolution of claims made by customers; or (3) A petition filed under... any of the foregoing with knowledge of a parallel proceeding shall promptly notify the Commission, by...

  8. The Binational Civic and Political Engagement of Mexican Migrant Hometown Associations and Federations in the United States

    Directory of Open Access Journals (Sweden)

    Xóchitl Bada

    2014-06-01

    Full Text Available This article focuses on the history and current situation of Mexican hometown associations (HTAs in the United States with a special emphasis on Chicago-based Mexican hometown associations and federations. It presents empirical evidence of new forms of binational engagement among Mexican migrant communities in the United States leading to the creation of a Mexican migrant civil society.

  9. Espanol mexicano y espanol chicano: Problemas y propuestas fundamentales (Mexican Spanish and Chicano Spanish: Fundamental Problems and Proposals).

    Science.gov (United States)

    Hidalgo, Margarita

    1987-01-01

    Discusses the rise of Mexican Spanish as a distinct variety of Spanish and describes the regional and social dialects of contemporary Mexican Spanish. Although countless similarities exist between Mexican Spanish and the Chicano Spanish spoken in the southwestern United States, Mexican Spanish shows greater variability. (GR)

  10. Moving In and Out of Bilingualism: Investigating Native Language Maintenance and Shift in Mexican-Descent Children. Research Report: 6.

    Science.gov (United States)

    Pease-Alvarez, Lucinda

    A study investigated patterns and influences in Mexican-American children's Spanish language maintenance and shift toward English dominance or monolingualism. Subjects were 64 Mexican-descent children, ages 8-9, of varying immigration backgrounds (Mexican-born, U.S.-born of Mexican-born parents, U.S.-born of U.S.-born parents), and their families…

  11. Mexican experience on migration and development 1990-2013

    Directory of Open Access Journals (Sweden)

    Rodolfo García Zamora

    Full Text Available After 40 years of a long rising emigration from Mexico to the United States, the number of Mexicans increased to 12 million in 2006, while the increased input of remittances reached $26 million dollars in 2007. Yet, the increasing migration and remittances mainly in Zacatecas and Michoacan states do not achieve economic and social development because of the persistent backwardness, unemployment and marginalization. It demands the need for new Policies of Development, Migration and Human Rights that allow exercising the right to not emigrate in a medium term. Positive products of this long migration are the Mexican Migrant Clubs and their Federations that elaborated the concrete development proposals. Whereas, the possibility that these proposals can become a Development, Migration and Human Rights, Comprehensive and Long Term State Policy will depend on the capacity and participation of Mexican Civil Society and the Transnational Communities in both countries.

  12. Acculturation and Life Satisfaction Among Immigrant Mexican Adults

    Directory of Open Access Journals (Sweden)

    Flavio F. Marsiglia

    2013-09-01

    Full Text Available The numbers of Mexican Americans living in the United States, many of whom are first generation immigrants, are increasing. The process of immigration and acculturation can be accompanied by stress, as an individual attempts to reconcile two potentially competing sets of norms and values and to navigate a new social terrain. However, the outcomes of studies investigating the relationship between levels of acculturation and well-being are mixed. To further investigate the dynamic of acculturation, this article will address the impact of acculturation and familismo, on reported life satisfaction and resilience among Mexican American adults living in the Southwest (N=307, the majority (89% of which are immigrants. The findings indicate that bilingual individuals report significantly higher levels of life satisfaction and resilience than their Spanish-speaking counterparts do. Speaking primarily English only predicted higher levels of resilience but not life satisfaction. Implications for social work practice with Mexican American immigrants are discussed.

  13. Men of Mexican Origin Who Abuse Women: A Qualitative Study.

    Science.gov (United States)

    Montalvo-Liendo, Nora; Matthews, Debra W; Gilroy, Heidi; Nava, Angeles; Gangialla, Christyn

    2018-03-01

    Current literature indicates that intimate partner violence is a complex phenomenon that exists worldwide. However, little is known about why some men of Mexican origin abuse women. This descriptive study was conducted to understand the experiences of men of Mexican origin who abuse their intimate partners. A qualitative research design was used to conduct this study in a south Texas border community adjacent to the United States-Mexico border. This study builds on existing research and furthers the knowledge related to the factors contributing to intimate partner violence, including cultural factors. The results also reinforce the negative impacts of intimate partner violence on children and the family structure. Further research is needed to support the development of a culturally appropriate prevention and intervention program for men of Mexican origin who abuse women and their families.

  14. [Observational study of craniofacial growth and development in Mexican children].

    Science.gov (United States)

    Fijikami, T K; Cedeño Pacheco, E

    1991-01-01

    The election of a investigation about craniofacial growing and development in Mexican children, was done due to a lack of national information in this rubric and as a fundamental part of the "growing and development in the scholastic" module of the Universidad Autónoma Metropolitana-Xochimilco, which work hypothesis was that "craniofacial growing and development in Mexican, 6 to 12 children in Xochimilco area are due to nutritional deficiency, second dentition eruption delay and dental maloclution "which was totality confirmed in a 100 Mexican facial characteristic children field work study, with cephalometric studies which permit to determine the craniofacial growing standard. This study was corroborated with a 40 children, 4 years later follow up.

  15. Volunteer work in the church among older Mexican Americans.

    Science.gov (United States)

    Krause, Neal; Hayward, R David

    2012-07-01

    The purpose of this study is to identify the factors that influence the amount of volunteer work that older Mexican Americans perform in the place where they worship. The relationship between religion and volunteering is viewed from a social identity perspective. Data from a nationally representative sample of older Mexican Americans suggest that Evangelical/Pentecostal church members spend more time performing volunteer work at church than older Mexican Americans who affiliate with other denominations. Moreover, the findings indicate that the difference in the amount of volunteering between the two groups can largely be explained by differences in the nature of the spiritual support that Evangelical/Pentecostal receive from their fellow church members as well as depth of their commitment to their faith.

  16. Identifying Strategic Groups: An Assessment in Mexican Franchises

    Directory of Open Access Journals (Sweden)

    Cesario Armando Flores Villanueva

    2017-07-01

    Full Text Available The formation of strategic groups in the franchising sector has been previously documented in the context of different countries. Our proposal is the franchise industry in Mexico should be formed by groups of differentiated franchisors. The identification and analysis of the different strategic groups formed in the franchise system of the Mexican market is the objective of this research. Our evaluation was performed using the factor analysis technique in a sample of 167 franchises of national origin. Seven strategic dimensions supported by the theory of scarce resources and agency theory make up the existence of differentiated groups of franchisors in the Mexican market. Our research confirmed the identification of five strategic groups called: rapid growth, converters, experienced and international franchisors, high entry fees and expensive conservatives, which use differentiated strategies to compete in the Mexican market.

  17. Scale and scope economies in Mexican private medical units.

    Science.gov (United States)

    Keith, Jorge; Prior, Diego

    2014-01-01

    To evaluate technical efficiency and potential presence of scale and scope economies in Mexican private medical units (PMU) that will improve management decisions. We used data envelopment analysis methods with inputs and outputs for 2 105 Mexican PMU published in 2010 by the Instituto Nacional de Estadística y Geografía from the "Estadística de Unidades Médicas Privadas con Servicio de Hospitalización (PEC-6-20-A)" questionnaire. The application of the models used in the paper found that there is a marginal presence of economies of scale and scope in Mexican PMU. PMU in Mexico must focus to deliver their services on a diversified structure to achieve technical efficiency.

  18. Scale and scope economies in Mexican private medical units

    Directory of Open Access Journals (Sweden)

    Jorge Keith

    2014-07-01

    Full Text Available Objective. To evaluate technical efficiency and potential presence of scale and scope economies in Mexican private medical units (PMU that will improve management decisions. Materials and methods. We used data envelopment analysis methods with inputs and outputs for 2 105 Mexican PMU published in 2010 by the Instituto Nacional de Estadística y Geografía from the “Estadística de Unidades Médicas Privadas con Servicio de Hospitalización (PEC-6-20-A” questionnaire. Results. The application of the models used in the paper found that there is a marginal presence of economies of scale and scope in Mexican PMU. Conclusions. PMU in Mexico must focus to deliver their services on a diversified structure to achieve technical efficiency.

  19. Training in the Mexican company: a study of job training

    Directory of Open Access Journals (Sweden)

    Alma Lilia Sapién Aguilar

    2014-12-01

    Full Text Available The processes of training and instruction in a medium-sized Mexican company are not being understood as an investment that contributes to business success.The aim of this study was to analyze these processes. The methodological approach was exploratory and descriptive with a non-experimental or ex post facto design. The Mexican Business Information System was consulted and 17 medium-sized companies in the industrial sector were randomly chosen. The results indicated that in the median Mexican company decisive actions must be taken in order to achieve that training and instruction are no longer seen as an unnecessary expense. They need to be understood as the best investment one can make in human resources. Therefore, training and instruction must become a part of the work culture of any organization.

  20. 2015 Brainhack Proceedings

    Directory of Open Access Journals (Sweden)

    R. Cameron Craddock

    2016-11-01

    Full Text Available Table of contents I1 Introduction to the 2015 Brainhack Proceedings R. Cameron Craddock, Pierre Bellec, Daniel S. Margules, B. Nolan Nichols, Jörg P. Pfannmöller A1 Distributed collaboration: the case for the enhancement of Brainspell’s interface AmanPreet Badhwar, David Kennedy, Jean-Baptiste Poline, Roberto Toro A2 Advancing open science through NiData Ben Cipollini, Ariel Rokem A3 Integrating the Brain Imaging Data Structure (BIDS standard into C-PAC Daniel Clark, Krzysztof J. Gorgolewski, R. Cameron Craddock A4 Optimized implementations of voxel-wise degree centrality and local functional connectivity density mapping in AFNI R. Cameron Craddock, Daniel J. Clark A5 LORIS: DICOM anonymizer Samir Das, Cécile Madjar, Ayan Sengupta, Zia Mohades A6 Automatic extraction of academic collaborations in neuroimaging Sebastien Dery A7 NiftyView: a zero-footprint web application for viewing DICOM and NIfTI files Weiran Deng A8 Human Connectome Project Minimal Preprocessing Pipelines to Nipype Eric Earl, Damion V. Demeter, Kate Mills, Glad Mihai, Luka Ruzic, Nick Ketz, Andrew Reineberg, Marianne C. Reddan, Anne-Lise Goddings, Javier Gonzalez-Castillo, Krzysztof J. Gorgolewski A9 Generating music with resting-state fMRI data Caroline Froehlich, Gil Dekel, Daniel S. Margulies, R. Cameron Craddock A10 Highly comparable time-series analysis in Nitime Ben D. Fulcher A11 Nipype interfaces in CBRAIN Tristan Glatard, Samir Das, Reza Adalat, Natacha Beck, Rémi Bernard, Najmeh Khalili-Mahani, Pierre Rioux, Marc-Étienne Rousseau, Alan C. Evans A12 DueCredit: automated collection of citations for software, methods, and data Yaroslav O. Halchenko, Matteo Visconti di Oleggio Castello A13 Open source low-cost device to register dog’s heart rate and tail movement Raúl Hernández-Pérez, Edgar A. Morales, Laura V. Cuaya A14 Calculating the Laterality Index Using FSL for Stroke Neuroimaging Data Kaori L. Ito, Sook-Lei Liew A15 Wrapping FreeSurfer 6 for use in

  1. Advanced materials and technologies. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Lindroos, V K; Alander, T K.R. [eds.; Helsinki Univ. of Technology, Otaniemi (Finland). Lab. of Physical Metallurgy and Materials Science

    1996-12-31

    The contents of the proceedings consist of three chapters, of which, the first discusses common megatrends, both nationally and globally, in different fields of materials technology. The second chapter is dealing with novel production and processing of base metals and, finally, the third chapter is related with current achievements and future goals of electronic, magnetic, optical and coating materials and their processing

  2. Proceedings of the geosciences workshop

    Energy Technology Data Exchange (ETDEWEB)

    None

    1991-01-01

    The manuscripts in these proceedings represent current understanding of geologic issues associated with the Weldon Spring Site Remedial Action Project (WSSRAP). The Weldon Spring site is in St. Charles County, Missouri. The proceedings are the record of the information presented during the WSSRAP Geosciences Workshop conducted on February 21, 1991. The objective of the workshop and proceedings is to provide the public and scientific community with technical information that will facilitate a common understanding of the geology of the Weldon Spring site, of the studies that have been and will be conducted, and of the issues associated with current and planned activities at the site. This coverage of geologic topics is part of the US Department of Energy overall program to keep the public fully informed of the status of the project and to address public concerns as we clean up the site and work toward the eventual release of the property for use by this and future generations. Papers in these proceedings detail the geology and hydrology of the site. The mission of the WSSRAP derives from the US Department of Energy's Surplus Facilities Management Program. The WSSRAP will eliminate potential hazards to the public and the environment and make surplus real property available for other uses to the extent possible. This will be accomplished by conducting remedial actions which will place the quarry, the raffinate pits, the chemical plant, and the vicinity properties in a radiologically and chemically safe condition. The individual papers have been catalogued separately.

  3. Workshop 97. Part III. Proceedings

    International Nuclear Information System (INIS)

    1996-12-01

    This volume of the Proceedings covers the following branches of science and technology: power systems and electrical engineering, electronics and measuring and communication engineering, optics, quantum electronics and photonics, microelectronics, and biomedical engineering. Out of the contributions, 2 have been input to INIS. (P.A.)

  4. Workshop 97. Part IV. Proceedings

    International Nuclear Information System (INIS)

    1996-12-01

    This volume of the Proceedings cover the following branches of science and technology: preservation and creation of the environment, architecture, town planning and visual arts, reliability, production systems and technology, nuclear engineering, transport engineering, and economics and business activities. Out of the contributions, 19 have been input to INIS. (P.A.)

  5. Advanced materials and technologies. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Lindroos, V.K.; Alander, T.K.R. [eds.] [Helsinki Univ. of Technology, Otaniemi (Finland). Lab. of Physical Metallurgy and Materials Science

    1995-12-31

    The contents of the proceedings consist of three chapters, of which, the first discusses common megatrends, both nationally and globally, in different fields of materials technology. The second chapter is dealing with novel production and processing of base metals and, finally, the third chapter is related with current achievements and future goals of electronic, magnetic, optical and coating materials and their processing

  6. International Women's Leadership Conference Proceedings.

    Science.gov (United States)

    Journal of Dental Education, 1999

    1999-01-01

    Presents proceedings of the American Association of Dental Schools' International Women's Leadership Conference. Addresses, panel presentations, and general-sessions topics included leadership training and promotion for women in dental education, women's health issues and research, the glass ceiling, infrastructures for research and training,…

  7. A review of the Mexican national innovation system

    Directory of Open Access Journals (Sweden)

    Samantha Rullán

    2015-12-01

    Full Text Available Governments and business leaders are increasingly aware of the role that innovation plays in economic growth, development and competitiveness. There are imperative challenges for Latin American countries, among them, poverty, social inclusion, sustainable development, climate change, natural disasters, productivity, improve the quality of education and health. Innovations are essential to drive economic growth and prosperity in the region. According to the Global Innovation Index (2015, Mexico is ranked 57th. Most of the research on innovation performance is mostly focused on technological innovation. Therefore, the main variables used, such as patents and number of scientific publications, do not always reflect the other types of innovations (i.e. business model, organizational, etc. that are developing in emerging markets. The aim of this paper is to analyze the Mexican innovation system using a broad concept with a focus on other types of innovation including cultural aspects to identify the main characteristics that distinguish and determine how innovation in Mexico is formed. Although the Mexican government has improved its institutional structure for innovation and its support policies, they need to evaluate programs and adjust incentive schemes based on performance to improve their innovation policy. Purpose – The purpose of this paper is to examine the Mexican National Innovation System using a broad concept with a focus on other types of innovation and including cultural aspects to identify some of the main characteristics that determine how innovation in Mexico is formed. Design/methodology/approach – The national innovation systems framework is used to review the Mexican innovation policy.A review of relevant literature on national innovation systems and Mexican innovation policies with data from the Global Innovation Index and INEGI were used for this paper. Findings – Higher private investment in R&D is needed to enhance

  8. Employer Sanctions and the Wages of Mexican Immigrants

    Directory of Open Access Journals (Sweden)

    Peter Brownell

    2017-07-01

    Full Text Available Wage differences between authorized and unauthorized Mexican immigrants can be explained by human capital factors prior to the 1986 passage of employer sanctions, which prohibited knowingly hiring unauthorized aliens. However, a significant post-1986 wage differential has been interpreted as employers “passing along” expected costs of sanctions through lower wages for unauthorized immigrants. I test this explanation using administrative data on employer sanctions enforcement, finding employer sanctions enforcement levels are related to Mexican immigrants’ wages but have no statistically significant differential effect based on legal status. Estimated savings to employers due to the pay gap are orders of magnitude larger than actual fines.

  9. Social and cultural influences among Mexican border entrepreneurs.

    Science.gov (United States)

    Díaz Bretones, Francisco; Cappello, Héctor M; Garcia, Pedro A

    2009-06-01

    Social and cultural conditions (including U.S. border and inland influence, role models within the family, and educational background) which affect locus of control and achievement motivation among Mexican entrepreneurs were explored among 64 selected entrepreneurs in two Mexican towns, one on the Mexico-U.S. border, the other located inland. Analyses showed that the border subsample scored higher on External locus of control; however, in both subsamples the father was an important element in the locus of control variable and the entrepreneur status. No statistically significant mean difference was noted for achievement motivation. Practical applications and limitations are discussed.

  10. Immigration and Wage Dynamics: Evidence from the Mexican Peso Crisis

    OpenAIRE

    Monras , Joan

    2015-01-01

    How does the US labor market absorb low-skilled immigration? I address this question using the 1995 Mexican Peso Crisis, an exogenous push factor that raised Mexican migration to the US. In the short run, high-immigration states see their low-skilled labor force increase and native low-skilled wages decrease, with an implied local labor demand elasticity of -.7. Internal relocation dissipates this shock spatially. In the long run, the only lasting consequences are for low-skilled natives who ...

  11. Study protocol: intervention in maternal perception of preschoolers' weight among Mexican and Mexican-American mothers.

    Science.gov (United States)

    Flores-Peña, Yolanda; He, Meizi; Sosa, Erica T; Avila-Alpirez, Hermelinda; Trejo-Ortiz, Perla M

    2018-05-30

    Childhood obesity is a public health issue negatively affecting children's physical and psychosocial health. Mothers are children's primary caregivers, thus key players in childhood obesity prevention. Studies have indicated that mothers underestimate their children's weight. If mothers are unaware of their children's weight problem, they are less likely to participate in activities preventing and treating excess weight. The "Healthy Change" intervention is designed to change maternal perception of child's weight (MPCW) through peer-led group health education in childcare settings. The "Healthy Change" is a multicenter two-arm randomized trial in four centers. Three centers are in Mexican States (Nuevo Leon, Tamaulipas, and Zacatecas). The fourth center is in San Antonio, Texas, USA. A total of 360 mother-child pairs (90 pairs per center) are to be randomly and evenly allocated to either the intervention or the control group. Intervention group will receive four-session group obesity prevention education. Control group will receive a four-session personal and food hygiene education. The education is delivered by trained peer-mother promotoras. Data will be collected using questionnaires and focus groups. The primary outcome is a change in proportion of mothers with accurate MPCW. Secondary outcomes include change in maternal feeding styles and practices, maternal self-efficacy and actions for managing child excessive weight gain. McNemar's Test will be used to test the primary outcome. The GLM Univariate procedure will be used to determine intervention effects on secondary outcomes. The models will include the secondary outcome measures as the dependent variables, treatment condition (intervention/control) as the fixed factor, and confounding factors (e.g., mother's education, children's gender and age) as covariates. Sub-analyses will be performed to compare intervention effects on primary and secondary outcomes between the samples from Mexico and Texas, USA

  12. Development of the Mexican electric power sector

    International Nuclear Information System (INIS)

    Escofet, A.

    1981-06-01

    In 1980 Mexico had a population of 68 million, mostly concentrated in a few cities with many other areas being practically unpopulated. The country is semi-industrialized, and in order to achieve better standards of living, economic growth will have to continue at about 7.5 percent or more, particularly if the population continues to increase at 2.9 percent per year. The total installed electrical capacity at the end of 1980 was 14 600 MW; the per capita consumption of electricity was 910 KWh. The present government has as a goal an 8 percent annual growth rate in gross domestic product until 1995, resulting in forecast of a 12.5 percent growth rate in the electric sector to about 410 TWh per year. Hydroelectric power could be used to produce 80 TWh a year by 2000 if capacity were quadrupled. The use of coal for the production of electricity is beginning, and it is planned to generate 40 TWh a year from this source by 2000. Geothermal power should yield 20 TWh by then. A goal has been set of 20 000 MW of installed nuclear capacity by the end of the century; this would produce about 130 TWh, leaving some 280 TWh to be generated by oil or gas. The planned nuclear program must include the development of a strong Mexican nuclear industry, so that in 20 years 80 percent of the nuclear plant components could be locally produced. Ultimately it is hoped that Mexico will have the capability of installing, with its own resources, five or six large nuclear plants per year

  13. The Mexican consensus on irritable bowel syndrome.

    Science.gov (United States)

    Carmona-Sánchez, R; Icaza-Chávez, M E; Bielsa-Fernández, M V; Gómez-Escudero, O; Bosques-Padilla, F; Coss-Adame, E; Esquivel-Ayanegui, F; Flores-Rendón, Á R; González-Martínez, M A; Huerta-Iga, F; López-Colombo, A; Méndez-Gutiérrez, T H; Noble-Lugo, A; Nogueira-de Rojas, J R; Raña-Garibay, R H; Remes-Troche, J M; Roesch-Dietlen, F; Schmulson, M J; Soto-Pérez, J C; Tamayo, J L; Uscanga, L F; Valdovinos, M Á; Valerio-Ureña, J; Zavala-Solares, M R

    2016-01-01

    Since the publication in 2009 of the Guidelines on the Diagnosis and Treatment of Irritable Bowel Syndrome of the Asociación Mexicana de Gastroenterología (2009 Guidelines), there have been significant advances in our knowledge of the epidemiology, pathophysiology, diagnosis, and treatment of this disease. To present a consensus review of the most current knowledge of IBS, updating the 2009 Guidelines by incorporating new internationally published scientific evidence, with a special interest in Mexican studies. The PubMed literature from January 2009 to March 2015 was reviewed and complemented through a manual search. Articles in English and Spanish were included and preference was given to consensuses, guidelines, systematic reviews, and meta-analyses. Statements referring to the different aspects of the disease were formulated and voted upon by 24 gastroenterologists employing the Delphi method. Once a consensus on each statement was reached, the quality of evidence and strength of recommendation were determined through the GRADE system. Forty-eight statements were formulated, updating the information on IBS and adding the complementary data that did not appear in the 2009 Guidelines regarding the importance of exercise and diet, diagnostic strategies, and current therapy alternatives that were analyzed with more stringent scientific vigor or that emerged within the last 5 years. We present herein a consensus review of the most relevant advances in the study of IBS, updating and complementing the 2009 Guidelines. Several studies conducted in Mexico were included. Copyright © 2016 Asociación Mexicana de Gastroenterología. Publicado por Masson Doyma México S.A. All rights reserved.

  14. Long-term surveillance plan for the Mexican Hat Disposal Site, Mexican Hat, Utah

    International Nuclear Information System (INIS)

    1996-02-01

    This plan describes the long-term surveillance activities for the Uranium Mill Tailings Remedial Action (UMTRA) Project disposal site at Mexican Hat, Utah. The U.S. Department of Energy (DOE) will carry out these activities to ensure that the disposal site continues to function as designed. This long-term surveillance plan (LTSP) was prepared as a requirement for acceptance under the U.S. Nuclear Regulatory Commission (NRC) general license for custody and long-term care of residual radioactive material (RRM). This LTSP (based on the DOE's Guidance for Implementing the UMTRA Project Long-term Surveillance Program), documents the land ownership interests and details how the long-term care of the disposal site will be accomplished

  15. Environmental assessment of remedial action at the Mexican Hat uranium mill tailings site, Mexican Hat, Utah

    International Nuclear Information System (INIS)

    1987-10-01

    This document assesses the environmental impacts of the proposed remedial action at the Mexican Hat uranium mill tailings site located on the Navajo Reservation in southern Utah. The site covers 235 acres and contains 69 acres of tailings and several of the original mill structures. Remedial action must be performed in accordance with standards and with the concurrence of the US Nuclear Regulatory Commission and the Navajo Nation. The proposed action is to stabilize the tailings within the present tailings site by consolidating the tailings and associated contaminated soils into a recontoured pile. A radon barrier of compacted earth would be constructed over the pile, and various erosion control measures would be taken to assure the long-term stability of the pile. The no action alternative is also assessed in this document. 240 refs., 12 figs., 20 tabs

  16. "Ganando Confianza": Research Focus Groups with Immigrant Mexican Mothers

    Science.gov (United States)

    Hausmann-Stabile, Carolina; Zayas, Luis H.; Runes, Sandra; Abenis-Cintron, Anna; Calzada, Esther

    2011-01-01

    Immigrant families with children with developmental disabilities must be served using culturally sensitive approaches to service and research to maximize treatment benefits. In an effort to better understand cultural issues relevant to the provision of parenting programs for immigrant Mexican mothers of children with developmental disabilities, we…

  17. Determinants of Coping Responses among Mexican American Adolescents.

    Science.gov (United States)

    Guinn, Bobby; Vincent, Vern

    2002-01-01

    Examined the relationship of perceived stress, self-esteem, acculturation, and gender to the coping response of Mexican American adolescents. Data from self-report surveys indicated that adolescents had relatively high perceived stress levels, low acculturation, and a moderate self-esteem, with no significant gender differences. Self-esteem was…

  18. Interparental Relations, Maternal Employment, and Fathering in Mexican American Families

    Science.gov (United States)

    Formoso, Diana; Gonzales, Nancy A.; Barrera, Manuel, Jr.; Dumka, Larry E.

    2007-01-01

    This study examined independent and interactive relations between the interparental relationship and maternal employment in predicting fathering within low-income, Mexican American two-parent families (N = 115). Interparental conflict was negatively related to quality fathering, and these relations were noted only for single-earner families. The…

  19. Discrimination of citrus tristeza virus (CTV) strains using Mexican ...

    African Journals Online (AJOL)

    Two strains of citrus tristeza virus (CTV) were studied for six years in Yaounde in the forest zone of Cameroon. These strains, SNCL2 and SNCL4, were characterized on Lisbon lemon in Nyombe in the littoral zone of Cameroon. They were inoculated onto combinations of Mexican lime/citrange Troyer. The virulent strain ...

  20. Family Stress and Coping for Mexican Origin Adolescents

    Science.gov (United States)

    Liu, Freda F.; Gonzales, Nancy A.; Fernandez, Aida Cristina; Millsap, Roger E.; Dumka, Larry E.

    2011-01-01

    Family-related stressors pose special challenges for adolescents of Mexican origin, given traditional cultural norms that compel youths to get involved with family problems despite their limited ability to effect change. The current study examines the prospective effects of coping strategies (i.e., active, distraction, avoidance, support-seeking,…

  1. A Mexican American Woman Encounters Sociology: An Autobiographical Perspective.

    Science.gov (United States)

    Williams, Norma

    1988-01-01

    Describes the author's experience of teaching bilingual educators. Identifies the bureaucratic structure of the school and the Mexican American culture as the two problem areas focused upon during the course. Concludes that her major areas of research interest in sociology are a direct product of her ethnicity, work experience, and this…

  2. Detecting Diabetic Blindness in Low-Income Mexican Adults

    Centers for Disease Control (CDC) Podcasts

    This podcast features Kenny Mendoza-Herrera, a former graduate student at the National Institute of Public Health of Mexico and one of the winners of PCD's 2017 Student Research Paper Contest. Kenny answers questions about his winning research and what impact his study has on the prevention of diabetic blindness and public health, particularly for Mexican adults.

  3. Prevalence of Bruxism among Mexican Children with Down Syndrome

    Science.gov (United States)

    Lopez-Perez, Ruben; Lopez-Morales, Patricia; Borges-Yanez, S. Aida; Maupome, Gerardo; Pares-Vidrio, Gustavo

    2007-01-01

    This study sought to determine the prevalence of bruxism in a Mexican community of children with Down syndrome, and to evaluate bruxism's relationship with age, sex, intellectual disability level, and type of chromosomal abnormality of trisomy 21. Using a cross-sectional design, 57 boys and girls (3 to 14 years old) were examined. Three approaches…

  4. Antibacterial and antifungal activities of some Mexican medicinal plants.

    Science.gov (United States)

    Ruiz-Bustos, E; Velazquez, C; Garibay-Escobar, A; García, Z; Plascencia-Jatomea, M; Cortez-Rocha, M O; Hernandez-Martínez, J; Robles-Zepeda, R E

    2009-12-01

    In Mexico about 4,000 plant species have some medicinal use. The aim of this work was to evaluate the antimicrobial activity of six Mexican medicinal plants against fungi and Gram-positive and Gram-negative bacteria. Methanolic extracts were prepared from the Mexican medicinal plants Amphypteringium adstrigens, Castella tortuosa, Coutarea latiflora, Ibervillea sonorae, Jatropha cuneata, and Selaginella lepidophylla. The antibacterial and antifungal activities of the plants were determined by the broth microdilution method and the radial growth inhibition assay, respectively. All Mexican plants tested showed antimicrobial activity. Among the six plant extracts analyzed, J. cuneata showed the highest growth-inhibitory activity against fungi, Gram-positive and Gram-negative bacteria (J. cuneata > A. adstrigens > C. latiflora > C. tortuosa > I. sonorae approximately S. lepidophylla). Shigella flexneri and Staphylococcus aureus were the most susceptible bacteria to plant extracts. Complete inhibition of S. flexneri growth was observed with J. cuneata methanolic extract at 90 microg/mL. This plant extract also showed the strongest antifungal activity against Fusarium verticillioides and Aspergillus niger. Our data suggest that the medicinal plants tested have important antimicrobial properties. This is the first report describing the antimicrobial activities of several of the Mexican medicinal plants used in this study.

  5. Production of both esters and biogas from Mexican poppy | Singh ...

    African Journals Online (AJOL)

    This paper details a dynamic evaluation of a procedure for extracting both, ester and biogas from seeds and waste of Mexican poppy (Argemone mexicana) using simple and inexpensive technique. Results showed that A. mexicana seed contains 30% oil. Through the process of transestrification, oil extracted from seed, ...

  6. Machismo sustains health and illness beliefs of Mexican American men.

    Science.gov (United States)

    Sobralske, Mary

    2006-08-01

    To inform nurse practitioners (NPs) about Mexican American men's health and illness beliefs and the ways in which these are influenced by their masculine identity and how they view themselves as men in their culture. The data sources used were based on a selected review of the literature about Mexican American men's health and illness beliefs and the concept of machismo. Several studies, including the author's study on Mexican American men's healthcare-seeking beliefs and behaviors and experience in providing primary health care to men across cultures, contributed new data. The meaning of manhood in the Mexican American culture is critical in understanding how men perceive health and illness and what they do when they are ill. Machismo enhances men's awareness of their health because they have to be healthy to be good fathers, husbands, brothers, sons, workers, and community members. Pain and disability are motivating factors in finding ways to regain their health. Men's health beliefs across cultures need further investigation by nurse researchers and NPs. How culture influences healthcare delivery to men should be better understood. If NPs are aware of men's views on masculinity, they are better prepared to understand and assist men in becoming more aware of their health status and to seek health care when appropriate.

  7. Exploratory Talk, Argumentation and Reasoning in Mexican Primary School Children

    Science.gov (United States)

    Rojas-Drummond, Sylvia; Zapata, Margarita Peon

    2004-01-01

    The study analyses the effects of training primary school children in the use of a linguistic tool called "Exploratory Talk" (ET) on their capacity for argumentation. ET allows for reasoned confrontation and negotiation of points of view, making the reasoning visible in the talk. Eighty-eight Mexican children from the 5th and 6th grades…

  8. The Attitudes of Mexican Parents Toward School Discipline

    Science.gov (United States)

    Ogletree, Earl J.; Rodriquez, Margarita

    1978-01-01

    Surveys the attitudes of Mexican parents toward school discipline of primary-level children in terms of the following questions: 1) will parents accept the use of corporal punishment in schools?, 2) what form of disciplinary measure will they accept or recommend?, 3) if parents accept corporal punishment, who will be the school disciplinarian, and…

  9. Attitudes toward Suicide among Mexican American and Anglo Youth.

    Science.gov (United States)

    Domino, George

    1981-01-01

    There were statistically significant differences between answers of 76 Anglo and 76 Mexican American youth on 35 of 100 opinion questionnaire items. Items centered on religion, psychopathology, aggression-impulsivity, acceptability of suicide, the "cry for help" dimension, and emotional impact. (Author/CM)

  10. Optimal transmission planning under the Mexican new electricity market

    International Nuclear Information System (INIS)

    Zenón, Eric; Rosellón, Juan

    2017-01-01

    This paper addresses electricity transmission planning under the new industry and institutional structure of the Mexican electricity market, which has engaged in a deep reform process after decades of a state-owned-vertically-integrated-non-competitive-closed industry. Under this new structure, characterized by a nodal pricing system and an independent system operator (ISO), we analyze welfare-optimal network expansion with two modeling strategies. In a first model, we propose the use of an incentive price-cap mechanism to promote the expansion of Mexican networks. In a second model, we study centrally-planned grid expansion in Mexico by an ISO within a power-flow model. We carry out comparisons of these models which provide us with hints to evaluate the actual transmission planning process proposed by Mexican authorities (PRODESEN). We obtain that the PRODESEN plan appears to be a convergent welfare-optimal planning process. - Highlights: • We model transmission planning (PRODESEN) in the Mexican new electricity market. • We propose a first model with a price-cap mechanism to promote network expansion. • In a second power-flow model, we study centrally-planned grid expansions. • The PRODESEN appears to be a convergent welfare-optimal planning process. • Incentive regulation could further help to implement such an optimal process.

  11. Pandemics and networks : The case of the Mexican flu

    NARCIS (Netherlands)

    Omic, J.; Van Mieghem, P.

    2010-01-01

    The recent widespread of the new Mexican flu and SARS show the high dependency on contemporary traveling patterns. The air transport network is recognized as an important channel of epidemic propagation for different diseases. In order to predict epidemic spreading and the influence of protection

  12. Effects of Malathion Dust and Mexican Tea Powder ( Chenopodium ...

    African Journals Online (AJOL)

    The experiment was conducted in the laboratory at the Bako Agricultural Research Center, from January to July 2013. Combinations of different rates of Malathion and Mexican tea powder were evaluated against the maize weevil in no choice situations. The treatments were laid out in a randomized complete design with ...

  13. PROTEIN & SENSORY ANALYSIS TO CHARACTERIZE MEXICAN CHIHUAHUA CHEESES

    Science.gov (United States)

    It has been established that native microflora in raw milk cheeses, including Queso Chihuahua, a Mexican cheese variety, contributes to the development of unique flavors through degradation of milk proteins resulting in the release of free amino acids and short peptides that influence the taste and ...

  14. Neighborhood Contexts, Fathers, and Mexican American Young Adolescents' Internalizing Symptoms

    Science.gov (United States)

    White, Rebecca M. B.; Roosa, Mark W.

    2012-01-01

    The family stress model posits that contextual stressors, such as neighborhood danger, negatively influence youth adjustment, including internalizing symptoms, via disruptions in parenting and family processes. The current study examined a culturally and contextually modified family stress model in a diverse sample of Mexican-origin fathers and…

  15. Cultural and Contextual Influences on Parenting in Mexican American Families

    Science.gov (United States)

    White, Rebecca M. B.; Roosa, Mark W.; Weaver, Scott R.; Nair, Rajni L.

    2009-01-01

    Family stress theory can explain associations between contextual stressors and parenting. The theory, however, has not been tested among Mexican Americans or expanded to include cultural-contextual risks. This study examined associations between neighborhood, economic, and acculturative stressors and parenting behaviors in a sample of 570…

  16. Good Mathematics Teaching from Mexican High School Students' Perspective

    Science.gov (United States)

    Martinez-Sierra, Gustavo

    2014-01-01

    This paper reports a qualitative research that identifies the characteristics of good mathematics teaching from the perspective of Mexican high school students. For this purpose, the social representations of a good mathematics teacher and a good mathematics class were identified in a group of 67 students. In order to obtain information, a…

  17. Using Media Literacy to Explore Stereotypes of Mexican Immigrants.

    Science.gov (United States)

    Vargas, Lucila; dePyssler, Bruce

    1998-01-01

    Examines media portrayals of Mexican immigrants, and interplay between these images and portrayals of U.S.-born Latinos. Argues that examining media images is imperative because the influence of media saturation is almost overwhelming. Suggests a media-literacy framework for developing abilities for interpreting media and giving students control…

  18. Parental Agency in Educational Decision Making: A Mexican American Example

    Science.gov (United States)

    McClain, Margy

    2010-01-01

    Background/Context: This article explores the experiences of one Mexican American family as they make a key curriculum choice for their 9-year-old son. Relatively little attention has been paid to parents' beliefs, attitudes, and, in particular, experiences as they actively engage in--and sometimes affect--their children's schooling. Parents'…

  19. The Free Trade Agreement and the Mexican health sector.

    Science.gov (United States)

    Laurell, A C; Ortega, M E

    1992-01-01

    This article presents a discussion of the probable implications for the Mexican health sector of the Free Trade Agreement (FTA) between the United States, Canada, and Mexico. The authors argue that the FTA should be seen as part of neoliberal policies adopted by the Mexican government in 1983 that are based on large-scale privatization and deregulation of labor relations. In this general context the health sector, which traditionally has been dominated by public institutions, is undergoing a deep restructuring. The main trends are the decapitalization of the public sector and a selective process of privatization that tends to constitute the private health sector in a field of capital accumulation. The FTA is likely to force a change in Mexican health legislation, which includes health services in the public social security system and recognizes the right to health, and to accelerate selective privatization. The U.S. insurance industry and hospital corporations are interested in promoting these changes in order to gain access to the Mexican market, estimated at 20 to 25 million persons. This would lead to further deterioration of the public institutions, increasing inequalities in health and strengthening the private sector. The historical trend toward the integration of a National Health Service in Mexico would be interrupted in favor of formation of a dual private-public system.

  20. Evaluating the Success of Educational Policy in Mexican Higher Education

    Science.gov (United States)

    Sagarra, Marti; Mar-Molinero, Cecilio; Rodríguez-Regordosa, Herberto

    2015-01-01

    State support in higher education (HE) is often justified on the grounds that HE is important for the development of the country. However, little analysis is normally done in order to assess the impact of education quality initiatives. The Mexican government has been engaging in a policy of HE quality improvement that can be traced to 1989. In…

  1. Implicit Race/Ethnic Prejudice in Mexican Americans

    Science.gov (United States)

    Garza, Christelle Fabiola; Gasquoine, Philip Gerard

    2013-01-01

    Implicit race/ethnic prejudice was assessed using Spanish- and English-language versions of an Implicit Association Test that used Hispanic/Anglo first names and pleasant/unpleasant words as stimuli. This test was administered to a consecutive sample of Mexican American adults residing in the Rio Grande Valley region of Texas of whom about…

  2. Teaching Is Still an Art, Mexican Teachers Remind Us.

    Science.gov (United States)

    Hill, Margaret

    1997-01-01

    Describes working with 14 Mexican English teachers for 2.5 years at an elementary school in Guadalajara to help them implement an effective whole language program. Describes how these teachers used models of rich language, familiar movies, drama creations, family stories, and their own artistic talents to enhance learning in their classrooms.…

  3. Newspaper Suppression During the Mexican War, 1846-1848.

    Science.gov (United States)

    Reilly, Tom

    A number of scholars have found that wartime conditions often bring about conflict between the press and the military. This study documents the various incidents between the United States Army and various Mexican and United States newspaper editors that led to at least ten cases of newspaper suppression, the occasional use of prior censorship, and…

  4. Mexican Proverbs: The Philosophy, Wisdom and Humor of a People.

    Science.gov (United States)

    Ballesteros, Octavio A.

    Careful reading of proverbs can aid an individual to develop self-awareness by providing insights into what one cultural group considers desirable human behavior. Respect for the elderly can be taught to the young through the study of proverbs. Through their proverbs, the Mexicans reveal their friendliness, love of animals, sense of humor, and…

  5. Institutions in the Mexican coffee sector : changes and responses

    NARCIS (Netherlands)

    Rodriguez Padron, B.

    2012-01-01

    Keywords: Cooperation, contract arrangements, traders´ performance, market uncertainty, diversification, coffee, Mexico.

    The main aim of this thesis is to investigate the institutional environment prevailing in the Mexican coffee sector and its effect on the producers, traders and

  6. Writer Identity Construction in Mexican Students of Applied Linguistics

    Science.gov (United States)

    Mora, Alberto

    2017-01-01

    The paper examines the connection between discursive and non-discursive features and the construction of writer identity. In particular, the paper compares and contrasts the writer identity development of two groups of undergraduate students of applied linguistics in the Mexican context, one made up of locally educated ones and the other composed…

  7. Mexican American Televison: Applied Anthropology and Public Television

    Science.gov (United States)

    Eiselein, E. B.; Marshall, Wes

    1976-01-01

    Fiesta Project provides a classic example of action anthropology in broadcasting. The project involved the research and production of a Spanish language public television series designed to attract, retain, and realistically help a Mexican American audience in southern Arizona. The project used anthropological research in initial program…

  8. Mexican American Women Pursuing Counselor Education Doctorates: A Narrative Inquiry

    Science.gov (United States)

    Hinojosa, Tamara J.; Carney, JoLynn V.

    2016-01-01

    The authors used narrative inquiry and Anzaldúa's (1999) bordlerlands theory to understand the cultural experiences of 5 Mexican American women in doctoral programs accredited by the Council for Accreditation of Counseling and Related Educational Programs. Results indicated that participants navigated multiple cultural spheres and that the…

  9. Periodontitis associated with chronic kidney disease among Mexican Americans.

    Science.gov (United States)

    Ioannidou, Effie; Hall, Yoshio; Swede, Helen; Himmelfarb, Jonathan

    2013-01-01

    In comparison to non-Hispanic whites, a number of health-care disparities, including poor oral health, have been identified among Hispanics in general and Mexican Americans in particular. We hypothesized that Mexican Americans with chronic kidney disease (CKD) would have higher prevalence of chronic periodontitis compared with Mexican Americans with normal kidney function, and that the level of kidney function would be inversely related to the prevalence of periodontal disease. We examined this hypothesis using the National Health and Nutrition Examination Survey 1988-1994 (NHANES III) data set. We followed the American Academy of Periodontology/Center for Disease Control and Prevention case definition for periodontitis. Glomerular filtration rate was estimated using the CKD-Epidemiology equation for Hispanic populations. The classification to CKD stages was based on the National Kidney Foundation Kidney Disease Outcomes Quality Initiative. Periodontitis prevalence increased across the kidney function groups showing a statistically significant dose-response association (Pperiodontitis compared with Mexican Americans with normal kidney function after adjusting for potential confounders such as smoking, diabetes, and socioeconomic status. Multivariate adjusted odds ratio for periodontitis significantly increased with 1, 5, and 10 mL/minute estimated glomerular filtration rate reduction from the mean. This is the first report, to the best our knowledge, that showed an increase of periodontitis prevalence with decreased kidney function in this population. © 2012 American Association of Public Health Dentistry.

  10. Universal Interconnection Technology Workshop Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Sheaffer, P.; Lemar, P.; Honton, E. J.; Kime, E.; Friedman, N. R.; Kroposki, B.; Galdo, J.

    2002-10-01

    The Universal Interconnection Technology (UIT) Workshop - sponsored by the U.S. Department of Energy, Distributed Energy and Electric Reliability (DEER) Program, and Distribution and Interconnection R&D - was held July 25-26, 2002, in Chicago, Ill., to: (1) Examine the need for a modular universal interconnection technology; (2) Identify UIT functional and technical requirements; (3) Assess the feasibility of and potential roadblocks to UIT; (4) Create an action plan for UIT development. These proceedings begin with an overview of the workshop. The body of the proceedings provides a series of industry representative-prepared papers on UIT functions and features, present interconnection technology, approaches to modularization and expandability, and technical issues in UIT development as well as detailed summaries of group discussions. Presentations, a list of participants, a copy of the agenda, and contact information are provided in the appendices of this document.

  11. FloCon 2006 Proceedings

    Science.gov (United States)

    2006-10-01

    sudden increases in traffic caused by a reference from another high- volume Internet service or news site . These events have to be distinguished from...SNORT: KICKASS_PORN DRAGON: PORN HARDCORE SOURCEDEST SOURCE SOURCE SOURCE DEST DEST DEST DEST Stepping stone 51.251.22.183 Username password Sept...RABINOVICH, M. Flash crowds and denial of service attacks: Characterization and implications for cdns and web sites . In In Proceedings of the International

  12. National Hydrogen Roadmap Workshop Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    None

    2002-04-01

    This document summarizes the presentations and suggestions put forth by officials, industry experts and policymakers in their efforts to come together to develop a roadmap for America''s clean energy future and outline the key barriers and needs to achieve the hydrogen vision. The National Hydrogen Roadmap Workshop was held April 2-3, 2002. These proceedings were compiled into a formal report, The National Hydrogen Energy Roadmap, which is also available online.

  13. Workshop 97. Part I. Proceedings

    International Nuclear Information System (INIS)

    1996-12-01

    The complete Proceedings, in 4 volumes, contain contributions by staff members of the Czech Technical University in Prague, the Technical University in Brno, and the Technical University (former University of Mining) in Ostrava, covering all branches of science and technology dealt with by the 3 universities. Part I includes contributions in mathematics, physics, engineering informatics and cybernetics, and computers. Out of these, 13 have been input to INIS. (P.A.)

  14. Nuclear Inter Jura'87 Proceedings

    International Nuclear Information System (INIS)

    1988-01-01

    The Proceedings of the 8. Congress of the International Nuclear Law Association (INLA) contain the papers presented at the Congress and the ensuing discussions. The following topics were dealt with: new orientations of nuclear law - its convergence and discordance with other fields of law; impact of international treaties; comparison with legal provisions of other high-technology sectors and optimization of nuclear law. Finally, the last session examined the Chernobyl accident and the legal gaps it revealed. (NEA) [fr

  15. Workshop 97. Part I. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    The complete Proceedings, in 4 volumes, contain contributions by staff members of the Czech Technical University in Prague, the Technical University in Brno, and the Technical University (former University of Mining) in Ostrava, covering all branches of science and technology dealt with by the 3 universities. Part I includes contributions in mathematics, physics, engineering informatics and cybernetics, and computers. Out of these, 13 have been input to INIS. (P.A.).

  16. Two decades of Mexican particle physics at Fermilab

    International Nuclear Information System (INIS)

    Roy Rubinstein

    2002-01-01

    This report is a view from Fermilab of Mexican particle physics at the Laboratory since about 1980; it is not intended to be a history of Mexican particle physics: that topic is outside the expertise of the writer. The period 1980 to the present coincides with the growth of Mexican experimental particle physics from essentially no activity to its current state where Mexican groups take part in experiments at several of the world's major laboratories. Soon after becoming Fermilab director in 1979, Leon Lederman initiated a program to encourage experimental physics, especially experimental particle physics, in Latin America. At the time, Mexico had significant theoretical particle physics activity, but none in experiment. Following a visit by Lederman to UNAM in 1981, a conference ''Panamerican Symposium on Particle Physics and Technology'' was held in January 1982 at Cocoyoc, Mexico, with about 50 attendees from Europe, North America, and Latin America; these included Lederman, M. Moshinsky, J. Flores, S. Glashow, J. Bjorken, and G. Charpak. Among the conference outcomes were four subsequent similar symposia over the next decade, and a formal Fermilab program to aid Latin American physics (particularly particle physics); it also influenced a decision by Mexican physicist Clicerio Avilez to switch from theoretical to experimental particle physics. The first physics collaboration between Fermilab and Mexico was in particle theory. Post-docs Rodrigo Huerta and Jose Luis Lucio spent 1-2 years at Fermilab starting in 1981, and other theorists (including Augusto Garcia, Arnulfo Zepeda, Matias Moreno and Miguel Angel Perez) also spent time at the Laboratory in the 1980s

  17. Market study on the Mexican market for electrical distribution equipment

    International Nuclear Information System (INIS)

    1991-01-01

    A brief historical survey of the development of the Mexican electric power sector is presented, along with an overview of the state of the Mexican economy since the late 1980s and the present characteristics of the Mexican electricity sector. The Mexican market for electric power generation and distribution equipment is then assessed, from the perspective of Canadian suppliers and manufacturers intending to enter this market. Projected consumption of electrical generation and distribution equipment in Mexico for 1994 is estimated at US$1,035,600,000 ($719.4 million in production, $356.9 million in imports, and $40.7 million in exports). This market increased 12.3% in 1990, and since power demand in Mexico has been growing faster than growth in capacity, it is possible that investments in the electricity sector will grow at faster rates. Items which are traditionally imported include nuclear reactors and related equipment, boilers, turbines, power breakers, valves, coal and ash handling equipment, relays, automatic controls, and chemical treatment equipment. The USA has the greatest share of the import market with 35%, followed by Japan (22%), Switzerland (18%), and Germany (13%). Canadian exports have concentrated on distribution equipment and only totalled $1.7 million in 1990. Electricity is distributed to some 16.6 million users over a national interconnected system having total installed capacity of 30,513 MW in 1991. There are plans to increase capacity by 9.7 GW by 1994 and another 37.4-47.8 GW between 1995 and 2010. Projections of electricity needs by region are listed along with the new power plants targeted for investment. Market liberalization and lowering of tariffs have made the Mexican market more accessible to exporters. 8 tabs

  18. The Dissolution of the Mexican-American Border and Redefinition of Chicano/a /Mexican Identity in Leslie Marmon Silko's Almanac of the Dead

    DEFF Research Database (Denmark)

    Harding, David

    2006-01-01

    In Leslie Marmon Silko's Almanac of the Dead, notions of Mexican identity are deconstructed. This article analyzes how Silko, through a variety of characters and sub-plotlines, brings to the surface hidden tensions in the contsruction of Mexican identity through the melding of the sangre limpia...

  19. Simplified proceeding as a civil procedure model

    Directory of Open Access Journals (Sweden)

    Олексій Юрійович Зуб

    2016-01-01

    Full Text Available Currently the directions for the development of modern civil procedural law such as optimization, facilitation, forwarding proceedings promoting the increase of the civil procedure efficiency factor are of peculiar importance. Their results are occurrence and functionality of simplified proceedings system designed to facilitate significantly hearing some categories of cases, promotion of their consideration within reasonable time and reduce legal expenses so far as it is possible. The category “simplified proceedings” in the native science of the procedural law is underexamined. A good deal of scientists-processualists were limited to studying summary (in the context of optimization as a way to improve the civil procedural form, summary proceedings and procedures functioning in terms of the mentioned proceedings, consideration of case in absentia as well as their modification. Among the Ukrainian scientist who studied some aspects of the simplified proceedings are: E. A. Belyanevych, V. I. Bobrik, S. V. Vasilyev, M. V. Verbitska, S. I. Zapara, A. A. Zgama, V. V. Komarov, D. D. Luspenuk, U. V. Navrotska, V. V. Protsenko, T. V. Stepanova, E. A. Talukin, S. Y. Fursa, M. Y. Shtefan others. The problems of the simplified proceedings were studied by the foreign scientists as well, such as: N. Andrews, Y. Y. Grubanon, N. A. Gromoshina, E. P. Kochanenko, J. Kohler, D. I. Krumskiy, E. M. Muradjan, I. V. Reshetnikova, U. Seidel, N. V. Sivak, M. Z. Shvarts, V. V. Yarkov and others. The paper objective is to develop theoretically supported, practically reasonable notion of simplified proceedings in the civil process, and also basing on the notion of simplified proceedings, international experience of the legislative regulation of simplified proceedings, native and foreign doctrine, to distinguish essential features of simplified proceedings in the civil process and to describe them. In the paper we generated the notion of simplified proceedings that

  20. THE MEXICAN CALORIE ALLOCATION AMONG THE WORKING CLASS IN THE AMERICAN WEST, 1870-1920

    Directory of Open Access Journals (Sweden)

    Scott Alan Carson

    2015-06-01

    Full Text Available When measures for material conditions are sparse or unreliable, height and weight measurements are now widely accepted proxies that reflect changing economic conditions. This study uses two biological measurements related to height and weight: the basal metabolic rate (BMR and calorie accounting. BMRs and calories of Mexicans in the American West remained constant, indicating that their diets did not vary with United States economic development, but Mexican BMRs and diets varied with occupations. Farmers and unskilled workers had greater BMRs and received more calories per day than workers in other occupations. During much of the late 19th and early 20th centuries, Mexicans born in Mexico received fewer calories in the US than Mexicans born in the West. Mexican nutrition and diets also did not vary by residence within the US, indicating that Mexican diets were similar across western states.

  1. Anxiety disorders among Mexican Americans and non-Hispanic whites in Los Angeles.

    Science.gov (United States)

    Karno, M; Golding, J M; Burnam, M A; Hough, R L; Escobar, J I; Wells, K M; Boyer, R

    1989-04-01

    This report from the Los Angeles site of the NIMH Epidemiologic Catchment Area study reveals significant ethnic and national origin differences in lifetime prevalence rates for three out of six specific, DSM-III-defined anxiety disorders. In the case of simple phobia, United States-born Mexican Americans report higher rates than native non-Hispanic whites or immigrant Mexican Americans, the latter two groups having similar rates. Mexican Americans born in the United States had higher rates of agoraphobia than immigrant Mexican Americans, and non-Hispanic whites reported higher lifetime rates of generalized anxiety disorder compared with both immigrant and native Mexican Americans. Neither ethnic nor national origin differences in lifetime prevalence rates were found for panic disorder, social phobia, and obsessive-compulsive disorder. Selective migration is postulated as a potential factor influencing prevalence differences between native and immigrant Mexican Americans.

  2. The Diffusion of Mexican Immigrants During the 1990s: Explanations and Impacts

    OpenAIRE

    David Card; Ethan G. Lewis

    2005-01-01

    Mexican immigrants were historically clustered in a few cities, mainly in California and Texas. During the past 15 years, however, arrivals from Mexico established sizeable immigrant communities in many "new" cities. We explore the causes and consequences of the widening geographic diffusion of Mexican immigrants. A combination of demand-pull and supply push factors explains most of the inter-city variation in inflows of Mexican immigrants over the 1990s, and also illuminates the most importa...

  3. Anatomy of the pectoral and forelimb muscles of wildtype and green fluorescent protein-transgenic axolotls and comparison with other tetrapods including humans: a basis for regenerative, evolutionary and developmental studies

    Science.gov (United States)

    Diogo, R; Tanaka, E M

    2012-01-01

    The axolotl Ambystoma mexicanum is one of the most used model organisms in evolutionary, developmental and regenerative studies, particularly because it can reconstitute a fully functional and complete forelimb/hindlimb. Surprisingly, there is no publication that describes all the pectoral and forelimb muscles of this species or provides a comparative framework between these muscles and those of other model organisms and of modern humans. In the present paper we describe and illustrate all these muscles in A. mexicanum and provide the first report about the myology of adults of a model organism that is based on analyses and dissections of both wildtype animals and transgenic animals that express green fluorescent protein (GFP) in muscle fibers. On the one hand, the inclusion of GFP-transgenic animals allows us to show the muscles as more commonly seen, and thus easier to understand, by current developmental and regenerative biologists. On the other hand, by including wildtype and GFP-transgenic animals and by visualizing these latter animals with and without a simultaneous transmission laser light, we were able to obtain a more complete and clearer understanding of the exact limit of the fleshy and tendinous parts of the muscles and their specific connections with the skeletal elements. This in turn allowed us to settle some controversies in previous anatomical and comparative studies. As most developmental, regenerative and evolutionary biologists are interested in comparing their observations of A. mexicanum with observations in other model organisms, and ultimately in using this information to increase the understanding of human evolution and medicine, we also provide tables showing the homologies between the pectoral and forelimb muscles of axolotls, of model organisms such as mice, frogs and chicken, and of Homo sapiens. An example illustrating the outcomes of using our methodology and of our observations is that they revealed that, contrary to what is often

  4. Anatomy of the pectoral and forelimb muscles of wildtype and green fluorescent protein-transgenic axolotls and comparison with other tetrapods including humans: a basis for regenerative, evolutionary and developmental studies.

    Science.gov (United States)

    Diogo, R; Tanaka, E M

    2012-12-01

    The axolotl Ambystoma mexicanum is one of the most used model organisms in evolutionary, developmental and regenerative studies, particularly because it can reconstitute a fully functional and complete forelimb/hindlimb. Surprisingly, there is no publication that describes all the pectoral and forelimb muscles of this species or provides a comparative framework between these muscles and those of other model organisms and of modern humans. In the present paper we describe and illustrate all these muscles in A. mexicanum and provide the first report about the myology of adults of a model organism that is based on analyses and dissections of both wildtype animals and transgenic animals that express green fluorescent protein (GFP) in muscle fibers. On the one hand, the inclusion of GFP-transgenic animals allows us to show the muscles as more commonly seen, and thus easier to understand, by current developmental and regenerative biologists. On the other hand, by including wildtype and GFP-transgenic animals and by visualizing these latter animals with and without a simultaneous transmission laser light, we were able to obtain a more complete and clearer understanding of the exact limit of the fleshy and tendinous parts of the muscles and their specific connections with the skeletal elements. This in turn allowed us to settle some controversies in previous anatomical and comparative studies. As most developmental, regenerative and evolutionary biologists are interested in comparing their observations of A. mexicanum with observations in other model organisms, and ultimately in using this information to increase the understanding of human evolution and medicine, we also provide tables showing the homologies between the pectoral and forelimb muscles of axolotls, of model organisms such as mice, frogs and chicken, and of Homo sapiens. An example illustrating the outcomes of using our methodology and of our observations is that they revealed that, contrary to what is often

  5. Hadron collider physics 2005. Proceedings

    International Nuclear Information System (INIS)

    Campanelli, M.; Clark, A.; Wu, X.

    2006-01-01

    The Hadron Collider Physics Symposia (HCP) are a new series of conferences that follow the merger of the Hadron Collider Conferences with the LHC Symposia series, with the goal of maximizing the shared experience of the Tevatron and LHC communities. This book gathers the proceedings of the first symposium, HCP2005, and reviews the state of the art in the key physics directions of experimental hadron collider research: - QCD physics - precision electroweak physics - c-, b-, and t-quark physics - physics beyond the Standard Model - heavy ion physics The present volume will serve as a reference for everyone working in the field of accelerator-based high-energy physics. (orig.)

  6. National Hydrogen Vision Meeting Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    None

    2001-11-01

    This document provides presentations and summaries of the notes from the National Hydrogen Vision Meeting''s facilitated breakout sessions. The Vision Meeting, which took place November 15-16, 2001, kicked off the public-private partnership that will pave the way to a more secure and cleaner energy future for America. These proceedings were compiled into a formal report, A National Vision of America''s Transition to a Hydrogen Economy - To 2030 and Beyond, which is also available online.

  7. The role of familism in weight loss treatment for Mexican American women.

    Science.gov (United States)

    McLaughlin, Elizabeth A; Campos-Melady, Marita; Smith, Jane Ellen; Serier, Kelsey N; Belon, Katherine E; Simmons, Jeremiah D; Kelton, Katherine

    2017-10-01

    Mexican American women are disproportionately affected by overweight/obesity and the health complications accompanying them, but weight loss treatments are less successful in this ethnic group. High levels of familism, a value reflecting obligation to family that supersedes attention to oneself, interfere with weight loss for Mexican American women. This mixed methods study investigated overweight Mexican American women's beliefs about how familism, and Mexican American culture, might hinder weight loss success, and how treatments might be culturally adapted. Results suggest a need to support women in their commitment to family while also helping them make changes. Recommendations for culturally adapted treatments are made.

  8. Ganando Confianza: Research Focus Groups with Immigrant Mexican Mothers.

    Science.gov (United States)

    Hausmann-Stabile, Carolina; Zayas, Luis H; Runes, Sandra; Abenis-Cintron, Anna; Calzada, Esther

    2011-03-01

    Immigrant families with children with developmental disabilities must be served using culturally sensitive approaches to service and research to maximize treatment benefits. In an effort to better understand cultural issues relevant to the provision of parenting programs for immigrant Mexican mothers of children with developmental disabilities, we conducted sustained focus groups through which we could learn more about our participants and thereby improve services. This paper reports on the challenges and lessons learned from these groups. We characterize the key lessons as (a) recruitment and retention is more than agreement to participate; (b) confidentiality is not just a word but an activity; (c) the complicated nature of language; (d) cultural norms shape the group process; (e) appreciating the value of taking time; and (f) gender issues and group interaction. Service providers and researchers who work with Mexican families may benefit from our experiences as they promote and develop programs and projects in the developmental disabilities field.

  9. New records of Mexican Tardigrada Nuevos registros de Tardigrada mexicanos

    Directory of Open Access Journals (Sweden)

    Łukasz Kaczmarek

    2011-12-01

    Full Text Available In 9 moss samples collected from Mexico, 6 tardigrade species, including 4 new records for the country, were found. The new records raise the number of known Mexican water bear species to forty-one. We provide a full list of the known Mexican tardigrade species and discuss some biogeographical and taxonomic issues.En 9 muestras de musgo recolectadas en México, se encontraron 6 especies de tardígrados, incluyendo 4 nuevos registros para el país. Los nuevos registros incrementaron a 41 el número de especies de tardígrados mexicanos conocidos. Se proporciona una lista completa de tardígrados mexicanos conocidos y se discuten algunas cuestiones biogeográficas y taxonómicas.

  10. Mexican journalists: an investigation of their emotional health.

    Science.gov (United States)

    Feinstein, Anthony

    2012-08-01

    Mexican journalists are frequently the victims of violence, often drug related. The purpose of the study was to assess their mental well-being. Of 104 journalists recruited from 3 news organizations, those who had stopped working on drug-related stories because of intimidation from the criminal drug cartels (n = 26) had significantly greater social dysfunction (p = .024); and more depressive (p = .001) and higher intrusive (p = .027), avoidance (p = .005), and arousal (p = .033) symptoms than journalists living and working under threat in regions of drug violence (n = 61). They also had more arousal (p = .05) and depressive (p = .027) symptoms than journalists (n = 17) never threatened before and living in regions without a drug problem. These findings provide preliminary data on the deleterious effects of drug-related violence on the Mexican media, amplifying the concerns expressed by journalist watchdog organizations monitoring the state of the press in the country. Copyright © 2012 International Society for Traumatic Stress Studies.

  11. CEOs´ monetary incentives and performance of Mexican firms

    Directory of Open Access Journals (Sweden)

    Karen Watkins-Fassler

    2017-02-01

    Full Text Available This paper analyzes if changes in CEO remuneration and the execution of CEO stock options impact firm performance, under an emerging market context. Data is obtained from 88 non-financial companies listed in the Mexican Stock Exchange (2001-2012. A dynamic panel specification is employed, and regressions are run through the Generalized Method of Moments. Some evidence is found on the negative relationship between flat monetary incentives and Mexican firm performance, specifically for normal times. In addition, financial incentives based on results (particularly CEO stock options do not imply higher firm performance. Results suggest that companies in particular contexts should move towards the development of CEOs, more than promoting mostly monetary incentives for boosting firm performance. Companies operating in Mexico will gain from hiring intrinsically motivated CEOs, together with testing different extrinsic rewards (neither flat nor stock options in order to attain additive effects on intrinsic motivation.

  12. Floating Marine Debris in waters of the Mexican Central Pacific.

    Science.gov (United States)

    Díaz-Torres, Evelyn R; Ortega-Ortiz, Christian D; Silva-Iñiguez, Lidia; Nene-Preciado, Alejandro; Orozco, Ernesto Torres

    2017-02-15

    The presence of marine debris has been reported recently in several oceans basins; there is very little information available for Mexican Pacific coasts, however. This research examined the composition, possible sources, distribution, and density of Floating Marine Debris (FMD) during nine research surveys conducted during 2010-2012 in the Mexican Central Pacific (MCP). Of 1820 floating objects recorded, 80% were plastic items. Sources of FMD were determined using key objects, which indicated that the most were related to the presence of the industrial harbor and of a growing fishing industry in the study area. Densities were relatively high, ranging from 40 to 2440objects/km 2 ; the highest densities were recorded in autumn. FMD were distributed near coastal regions, mainly in Jalisco, influenced by river outflow and surface currents. Our results seem to follow worldwide trends and highlight the need for further studies on potential ecological impacts within coastal waters of the MCP. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Foreign firms to get equal opportunity in Mexican selloff plans

    International Nuclear Information System (INIS)

    Wood, A.; Alvarez, C.

    1993-01-01

    Petroleos Mexicanos (Pemex) has not finalized details of its long-awaited petrochemical privatization program. However, the state oil group has made it clear the selloff schedule, due to begin during the next two months, will give equal investment opportunity to foreign firms, dashing the hopes of Mexican groups that they would be given first right of refusal in the privatization program. Meanwhile, Pemex has agreed with Shell Oil on a previously announced refining joint venture involving Shell's 225,000-bbl/day refinery at Deer Park, TX. Under the plan, Pemex will purchase a 50% stake in the refinery and join Shell in a $1-billion upgrade with would enable it to handle more Mexican crude. Sources believe that Shell and other US oil groups are interested in acquiring assets from Pemex Petroquimica

  14. Forecasting the electricity consumption of the Mexican border states maquiladoras

    Energy Technology Data Exchange (ETDEWEB)

    Flores, C.E.; Phelan, P.E. [Arizona State Univ., Dept. of Mechanical and Aerospace Engineering, Tempe, AZ (United States); Mou, J.-I. [Taiwan Semiconductor Manufacturing Co., Operation Planning Div., Hsin-Chu (Taiwan); Bryan, H. [Arizona State Univ., School of Architecture, Tempe, AZ (United States)

    2004-07-01

    The consumption of electricity by maquiladora industries in the Mexican border states is an important driver for determining future powerplant needs in that area. An industrial electricity forecasting model is developed for the border states' maquiladoras, and the outputs are compared with a reference forecasting model developed for the US industrial sector, for which considerably more data are available. This model enables the prediction of the effect of implementing various energy efficiency measures in the industrial sector. As an illustration, here the impact of implementing energy-efficient lighting and motors in the Mexican border states' maquiladoras was determined to be substantial. Without such energy efficiency measures, electricity consumption for these industries is predicted to rise by 64% from 2001 to 2010, but if these measures are implemented on a gradual basis over the same time period, electricity consumption is forecast to rise by only 36%. (Author)

  15. Mexican journals of educational research towards mainstream dissemination of science

    Directory of Open Access Journals (Sweden)

    Cabrera-Flores, Mayer

    2014-08-01

    Full Text Available The purpose of this study is to analyze the Electronic Journal of Educational Research (REDIE on its path towards the common manner of scientific dissemination. This research presents the evolution of Mexican policy with regards to the journals, the situation of the Educational Research Mexican journals, and its profundity relating to REDIE. In its evolution, there were three moments that stood out the most: the standardization of quality criteria, the digitalization and open access of the scientific journals, those that came together with REDIE like REDALYC and LATINDEX , and the individual initiatives of those journals that motivated the development of the scientific dissemination in Mexico. The investigation concludes with the realization of the necessity of achieving agreement on the efforts of various principal actors: governmental bodies, institutions, and academic communities.

  16. Implementation of Haccp in the Mexican Poultry Processing Industry

    Science.gov (United States)

    Maldonado-Siman, Ema; Martínez-Hernández, Pedro Arturo; Ruíz-Flores, Agustín; García-Muñiz, José G.; Cadena-Meneses, José A.

    Hazard Analysis and Critical Control Point (HACCP) is a safety and quality management tool used as major issue in international and domestic trade in food industry. However, detailed information on costs and benefits of HACCP implementation is needed to provide appropriate advice to food processing plants. This paper reports on the perceptions of costs and benefits by the Mexican poultry processing plants and sale destinations. The results suggest that the major costs of implementing and operating HACCP within poultry processing plants are record keeping and external technical advice. The main benefit indicated by the majority of processing plants is a reduction in microbial counts. Over 39% of poultry production is sent to nation-wide chains of supermarkets, and less than 13% is sent to international markets. It was concluded that the adoption of HACCP by the Mexican poultry processing sector is based on the concern to increase and keep the domestic market, rather than to compete in the international market.

  17. Determinants of Adherence to Living on Dialysis for Mexican Americans

    Directory of Open Access Journals (Sweden)

    Shirley A. Wells

    2015-03-01

    Full Text Available This study explores perceptions that affect adherence behaviors among Mexican Americans living with dialysis. In-depth narrative interviews were conducted with 15 Mexican Americans with end-stage renal disease (ESRD living on dialysis, 15 family members, and 6 health care personnel who provided care to them. Four themes emerged: (a positive influences to adherence, (b obstacles to adherence, (c daily activity losses, and (d fears about living with dialysis. From the findings, the perceptions given for non-adherence with the dialysis regimen ranged from denial of the condition, lack of pre-education, to cultural factors. Those given for adherence included prolonged life, family, and hope of getting a transplant. Health care providers were the reminder to adhere. Several cultural factors influenced their adherence perceptions. Strategies to enhance adherence behaviors should focus on knowledge about dialysis, use of the collective efficacy of the family, and the inclusion of cultural values.

  18. Mexican Public Opinion in the aftermath of the 2006 Elections

    Directory of Open Access Journals (Sweden)

    Alejandro Moreno

    2008-01-01

    Full Text Available In this article, I analyze public opinion about the 2006 Mexican presidential election in the context of the post–election conflict. My goal is to determine which individual–level variables influenced opinions about the post–election conflict. The analysis focuses on individual positions about the election fairness, confidence in the electoral Tribunal, claims for a full recount, and the public's stands on street protests and mobilization, among others. I use the Mexican component of the Comparative National Election Project (CNEP, conducted for the first time in Mexico in 2006 as a two–wave, preelection and postelection, panel design. The results highlight the importance of political predispositions in the analysis of public opinion in Mexico.

  19. MEXICAN ADMINISTRATIVE LAW AGAINST CORRUPTION: SCOPE AND FUTURE

    OpenAIRE

    Márquez, Daniel

    2016-01-01

    This work gives a synopsis of the evolution of public administration control mechanisms in Mexico. It highlights the instrumental nature of oversight, as well as regulatory and assessment aspects, and discusses issues like the historical design of the control instruments used in Mexican public administration. Certain social and political aspects from a legal perspective of administrative anti-corruption regulations are then underscored. The article concludes by drawing attention to the fact t...

  20. Rethinking State emerging as a Sinaloa mexican migration

    OpenAIRE

    Pintor Sandoval, Renato; Sánchez Sánchez, Ernesto

    2013-01-01

    Objective: this paper aims at analyzing the different studies that examined theinternational migration of people from Sinaloa to the United States. This research contextualizes the importance of Sinaloa within the current Mexican migration map to the American Union.Methodology: a documentary methodology based on national surveys was used. These surveys involved the region mentioned. Several case studieswere also carried out. Results: the results show that Sinaloa has been directly involved in...

  1. Factors associated with learning management in Mexican micro-entrepreneurs

    Directory of Open Access Journals (Sweden)

    Alejandro Mungaray Lagarda

    2016-10-01

    Full Text Available The learning capacity of social based Mexican micro-entrepreneurs to generate new knowledge and incorporate it to its products and services is evaluated. The above is done through a confirmatory factor analysis and structural linear equation system, and the presence of static and dynamic dimensions in learning capacity, which are represented by individual stocks and flows of knowledge. The positive relationship between them demonstrates the presence of learning processes that impact positively their economic performance.

  2. Have the Mexican Drug Cartels Evolved into a Terrorist Insurgency?

    Science.gov (United States)

    2013-06-14

    individual police officers and journalists.55 Originally, the Gulf Cartel recruited them from Mexico’s Special Operations Forces, known as Grupo Aeromóvil de ...fluid situation surrounding the Mexican drug war has led to much speculation about how to classify the powerful drug cartels conducting it. There is... conducting it. There is literature debating whether the cartels are merely a criminal enterprise or whether the cartels represent a new terrorist

  3. Synonyms for some species of Mexican anoles (Squamata: Dactyloidae).

    Science.gov (United States)

    De Oca, Adrián Nieto Montes; Poe, Steven; Scarpetta, Simon; Gray, Levi; Lieb, Carl S

    2013-01-01

    We studied type material and freshly collected topotypical specimens to assess the taxonomic status of five names associated with species of Mexican Anolis. We find A. schmidti to be a junior synonym of A. nebulosus, A. breedlovei to be a junior synonym of A. cuprinus, A. polyrhachis to be a junior synonym of A. rubiginosus, A. simmonsi to be a junior synonym of A. nebuloides, and A. adleri to be a junior synonym of A. liogaster.

  4. Going Global: Key Insights from Two Mexican Companies

    OpenAIRE

    Martha RIVERA; Silvia CACHO-ELIZONDO

    2015-01-01

    This paper explores how Mexican companies in different industries have achieved international expansion, while at the same time preserving local elements in executing their strategies. For this initial stage of research, the analysis focuses on two companies: a) Grupo Bimbo, the number one company in the bakery industry worldwide and b) KidZania, one of the world’s top indoor family entertainment centers. The research methodology is based on in-depth interviews with CEOs and key executives fr...

  5. Crowd behaves as excitable media during Mexican wave

    OpenAIRE

    Farkas, Illes; Helbing, Dirk; Vicsek, Tamas

    2002-01-01

    Mexican wave, or La Ola, first widely broadcasted during the 1986 World Cup held in Mexico, is a human wave moving along the stands of stadiums as one section of spectators stands up, arms lifting, then sits down as the next section does the same. Here we use variants of models originally developed for the description of excitable media to demonstrate that this collective human behaviour can be quantitatively interpreted by methods of statistical physics. Adequate modelling of reactions to tr...

  6. Social support, stressors, and frailty among older Mexican American adults.

    Science.gov (United States)

    Peek, M Kristen; Howrey, Bret T; Ternent, Rafael Samper; Ray, Laura A; Ottenbacher, Kenneth J

    2012-11-01

    There is little research on the effects of stressors and social support on frailty. Older Mexican Americans, in particular, are at higher risk of medical conditions, such as diabetes, that could contribute to frailty. Given that the Mexican American population is rapidly growing in the United States, it is important to determine whether there are modifiable social factors related to frailty in this older group. To address the influence of social support and stressors on frailty among older Mexican Americans, we utilized five waves of the Hispanic Established Populations for the Epidemiologic Study of the Elderly (Hispanic EPESE) to examine the impact of stressors and social support on frailty over a 12-year period. Using a modified version of the Fried and Walston Frailty Index, we estimated the effects of social support and stressors on frailty over time using trajectory modeling (SAS 9.2, PROC TRAJ). We first grouped respondents according to one of three trajectories: low, progressive moderate, and progressive high frailty. Second, we found that the effects of stressors and social support on frailty varied by trajectory and by type of stressor. Health-related stressors and financial strain were related to increases in frailty over time, whereas social support was related to less-steep increases in frailty. Frailty has been hypothesized to reflect age-related physiological vulnerability to stressors, and the analyses presented indicate partial support for this hypothesis in an older sample of Mexican Americans. Future research needs to incorporate measures of stressors and social support in examining those who become frail, especially in minority populations.

  7. Fluid intake in Mexican adults: a cross-sectional study

    OpenAIRE

    Martinez, Homero

    2014-01-01

    Introduction: An adequate hydration is critical for a series of body functions, including proper regulation of core body temperature, elimination of waste metabolites by the kidney and maintenance of normal physical and cognitive functions. Some institutions have set recommendations for adequate intake of water, but these recommendations vary widely. Objective: To estimate the usual daily consumption of fluids (water and all other beverages) by a selective sample of Mexican population. Method...

  8. On the Security of Mexican Digital Fiscal Documents

    OpenAIRE

    González García, Vladimir; Rodríguez Henríquez, Francisco; Cruz Cortés, Nareli

    2008-01-01

    In January 2005, the Mexican Tributary Administration System (SAT) introduced an official norm that stipulates how to generate electronic invoices that were termed by SAT, Comprobante Fiscal Digital (CFD). Supporting the CFD service implies the exchange of confidential information over Internet and other communication channels that are intrinsically highly vulnerable. Therefore, it becomes indispensable to incorporate to this service reliable and sound information security mechanisms. In the ...

  9. The Role of Religion in the Mexican Drug War

    Science.gov (United States)

    2011-10-28

    operations. His interest is in the “…role religion plays in motivating and justifying actions…” in the operational environment.1 His article and the...emptied of supernatural meaning and one in which ‘mystery’ no longer played a part.”18 In this form of secularization mystery, superstition, and... article /Mexico-catches-reputed-leader-of-La-Familia-cartel- 2078363.php 23 Grayson, La Familia Drug Cartel: Implications for U.S.-Mexican Security, 5

  10. 4 CFR 28.132 - Disciplinary proceedings.

    Science.gov (United States)

    2010-01-01

    ... Corrective Action, Disciplinary and Stay Proceedings § 28.132 Disciplinary proceedings. (a) If the General Counsel determines after any investigation under 31 U.S.C. 752(b) that disciplinary action should be... ordering disciplinary action. (d) A final order of the Board may order disciplinary action consisting of...

  11. 36 CFR 218.14 - Judicial proceedings.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Judicial proceedings. 218.14... ADMINISTRATIVE REVIEW PROCESSES Predecisional Administrative Review Process for Hazardous Fuel Reduction Projects Authorized by the Healthy Forests Restoration Act of 2003 § 218.14 Judicial proceedings. The objection...

  12. Digital sustainable publication of legacy parliamentary proceedings

    NARCIS (Netherlands)

    Marx, M.; Aders, N.; Schuth, A.

    2010-01-01

    We address the problem of publishing parliamentary proceedings in a digital sustainable manner. We give an extensive requirements analysis, and based on that propose a uniform XML format. We evaluated our approach by collecting and automatically processing proceedings from six parliaments spanning

  13. 19 CFR 212.03 - Proceedings covered.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 3 2010-04-01 2010-04-01 false Proceedings covered. 212.03 Section 212.03 Customs Duties UNITED STATES INTERNATIONAL TRADE COMMISSION INVESTIGATIONS OF UNFAIR PRACTICES IN IMPORT TRADE IMPLEMENTATION OF THE EQUAL ACCESS TO JUSTICE ACT General Provisions § 212.03 Proceedings covered. (a) The Act...

  14. Proceedings of Asia congress on radiation protection

    International Nuclear Information System (INIS)

    1993-01-01

    203 articles were collected in the proceedings. The contents of the proceedings included the principle and practices of radiation protection, biological effects of radiation, radiation monitoring, protection in medical and other fields, radiation dosimetry, nuclear energy and the environment, natural radiation, radioactive waste management, and other radiation protection issues

  15. 29 CFR 16.104 - Proceedings covered.

    Science.gov (United States)

    2010-07-01

    ... future rate or is primarily rule-making is not covered. Proceedings to grant or renew licenses are also... Administration: (i) Proceedings under the Workforce Investment Act at 29 U.S.C. 2936, where the Department... implementing regulations. (ii) Conformity and compliance under the Federal Unemployment Tax Act at 26 U.S.C...

  16. Proceedings 19th Central Hardwood Forest Conference

    Science.gov (United States)

    John W. Groninger; Eric J. Holzmueller; Clayton K. Nielsen; Daniel C., eds. Dey

    2014-01-01

    Proceedings from the 2014 Central Hardwood Forest Conference in Carbondale, IL. The published proceedings include 27 papers and 47 abstracts pertaining to research conducted on biofuels and bioenergy, forest biometrics, forest ecology and physiology, forest economics, forest health including invasive species, forest soils and hydrology, geographic information systems,...

  17. XXVII. Days of Radiation Protection. Conference Proceedings

    International Nuclear Information System (INIS)

    2005-11-01

    The publication has been set up as a proceedings of the conference dealing with health protection during work with ionizing radiation for different activities which involve the handling of ionizing radiation sources. The main conference topics are focused on current problems in radiation protection and radioecology. In this proceedings totally 83 papers are published

  18. 29 CFR 2204.104 - Proceedings covered.

    Science.gov (United States)

    2010-07-01

    ... Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH REVIEW COMMISSION IMPLEMENTATION OF THE EQUAL ACCESS TO JUSTICE ACT IN PROCEEDINGS BEFORE THE OCCUPATIONAL SAFETY AND HEALTH REVIEW... covered are the following proceedings under section 10(c), 29 U.S.C. 659(c), of the OSH Act: (a) Contests...

  19. Mexican-origin parents' work conditions and adolescents' adjustment.

    Science.gov (United States)

    Wheeler, Lorey A; Updegraff, Kimberly A; Crouter, Ann

    2015-06-01

    Mexican-origin parents' work experiences are a distal extrafamilial context for adolescents' adjustment. This 2-wave multiinformant study examined the prospective mechanisms linking parents' work conditions (i.e., self-direction, work pressure, workplace discrimination) to adolescents' adjustment (i.e., educational expectations, depressive symptoms, risky behavior) across the transition to high school drawing on work socialization and spillover models. We examined the indirect effects of parental work conditions on adolescent adjustment through parents' psychological functioning (i.e., depressive symptoms, role overload) and aspects of the parent-adolescent relationship (i.e., parental solicitation, parent-adolescent conflict), as well as moderation by adolescent gender. Participants were 246 predominantly immigrant, Mexican-origin, 2-parent families who participated in home interviews when adolescents were approximately 13 and 15 years of age. Results supported the positive impact of fathers' occupational self-direction on all 3 aspects of adolescents' adjustment through decreased father-adolescent conflict, after controlling for family socioeconomic status and earner status, and underemployment. Parental work pressure and discrimination were indirectly linked to adolescents' adjustment, with different mechanisms emerging for mothers and fathers. Adolescents' gender moderated the associations between fathers' self-direction and girls' depressive symptoms, and fathers' experiences of discrimination and boys' risk behavior. Results suggest that Mexican-origin mothers' and fathers' perceptions of work conditions have important implications for multiple domains of adolescents' adjustment across the transition to high school. (c) 2015 APA, all rights reserved).

  20. Metabolic Syndrome Prevalence among Northern Mexican Adult Population

    Science.gov (United States)

    Salas, Rogelio; Bibiloni, Maria del Mar; Ramos, Esteban; Villarreal, Jesús Z.; Pons, Antoni; Tur, Josep A.; Sureda, Antoni

    2014-01-01

    Background and Aims Dietary habits in the Mexican population have changed dramatically over the last few years, which are reflected in increased overweight and obesity prevalence. The aim was to examine the prevalence of metabolic syndrome (MetS) and associated risk factors in Northern Mexican adults aged ≥16 years. Methods and Results The study was a population-based cross-sectional nutritional survey carried out in the State of Nuevo León, Mexico. The study included a sub-sample of 1,200 subjects aged 16 and over who took part in the State Survey of Nutrition and Health–Nuevo León 2011/2012. Anthropometric measurements, physical activity, blood pressure and fasting blood tests for biochemical analysis were obtained from all subjects. The prevalence of MetS in Mexican adults aged ≥16 years was 54.8%, reaching 73.8% in obese subjects. This prevalence was higher in women (60.4%) than in men (48.9%) and increased with age in both genders. Multivariate analyses showed no evident relation between MetS components and the level of physical activity. Conclusions Obese adults, mainly women, are particularly at risk of developing MetS, with the associated implications for their health. The increasing prevalence of MetS highlights the need for developing strategies for its early detection and prevention. PMID:25141255

  1. Metabolic syndrome prevalence among Northern Mexican adult population.

    Science.gov (United States)

    Salas, Rogelio; Bibiloni, Maria del Mar; Ramos, Esteban; Villarreal, Jesús Z; Pons, Antoni; Tur, Josep A; Sureda, Antoni

    2014-01-01

    Dietary habits in the Mexican population have changed dramatically over the last few years, which are reflected in increased overweight and obesity prevalence. The aim was to examine the prevalence of metabolic syndrome (MetS) and associated risk factors in Northern Mexican adults aged ≥ 16 years. The study was a population-based cross-sectional nutritional survey carried out in the State of Nuevo León, Mexico. The study included a sub-sample of 1,200 subjects aged 16 and over who took part in the State Survey of Nutrition and Health-Nuevo León 2011/2012. Anthropometric measurements, physical activity, blood pressure and fasting blood tests for biochemical analysis were obtained from all subjects. The prevalence of MetS in Mexican adults aged ≥ 16 years was 54.8%, reaching 73.8% in obese subjects. This prevalence was higher in women (60.4%) than in men (48.9%) and increased with age in both genders. Multivariate analyses showed no evident relation between MetS components and the level of physical activity. Obese adults, mainly women, are particularly at risk of developing MetS, with the associated implications for their health. The increasing prevalence of MetS highlights the need for developing strategies for its early detection and prevention.

  2. Genetic Epidemiology of Type 2 Diabetes in Mexican Mestizos

    Directory of Open Access Journals (Sweden)

    Eiralí Guadalupe García-Chapa

    2017-01-01

    Full Text Available There are currently about 415 million people with diabetes worldwide, a figure likely to increase to 642 million by 2040. In 2015, Mexico was the second Latin American country and sixth in the world in prevalence of this disorder with nearly 11.5 million of patients. Type 2 diabetes (T2D is the main kind of diabetes and its etiology is complex with environmental and genetic factors involved. Indeed, polymorphisms in several genes have been associated with this disease worldwide. To estimate the genetic epidemiology of T2D in Mexican mestizos a systematic bibliographic search of published articles through PubMed, Scopus, Google Scholar, and Web of Science was conducted. Just case-control studies of candidate genes about T2D in Mexican mestizo inhabitants were included. Nineteen studies that met the inclusion criteria were found. In total, 68 polymorphisms of 41 genes were assessed; 26 of them were associated with T2D risk, which were located in ABCA1, ADRB3, CAPN10, CDC123/CAMK1D, CDKAL1, CDKN2A/2B, CRP, ELMO1, FTO, HHEX, IGF2BP2, IRS1, JAZF1, KCNQ1, LOC387761, LTA, NXPH1, SIRT1, SLC30A8, TCF7L2, and TNF-α genes. Overall, 21 of the 41 analyzed genes were associated with T2D in Mexican mestizos. Such a genetic heterogeneity compares with findings in other ethnic groups.

  3. Metabolic syndrome prevalence among Northern Mexican adult population.

    Directory of Open Access Journals (Sweden)

    Rogelio Salas

    Full Text Available Dietary habits in the Mexican population have changed dramatically over the last few years, which are reflected in increased overweight and obesity prevalence. The aim was to examine the prevalence of metabolic syndrome (MetS and associated risk factors in Northern Mexican adults aged ≥ 16 years.The study was a population-based cross-sectional nutritional survey carried out in the State of Nuevo León, Mexico. The study included a sub-sample of 1,200 subjects aged 16 and over who took part in the State Survey of Nutrition and Health-Nuevo León 2011/2012. Anthropometric measurements, physical activity, blood pressure and fasting blood tests for biochemical analysis were obtained from all subjects. The prevalence of MetS in Mexican adults aged ≥ 16 years was 54.8%, reaching 73.8% in obese subjects. This prevalence was higher in women (60.4% than in men (48.9% and increased with age in both genders. Multivariate analyses showed no evident relation between MetS components and the level of physical activity.Obese adults, mainly women, are particularly at risk of developing MetS, with the associated implications for their health. The increasing prevalence of MetS highlights the need for developing strategies for its early detection and prevention.

  4. Reproductive rights violations reported by Mexican women with HIV.

    Science.gov (United States)

    Kendall, Tamil

    2009-01-01

    Demand for reproductive health services by people with HIV is increasing, as is the urgency of protecting and promoting their reproductive rights. The reproductive rights of Mexicans with HIV are formally protected by the constitution and by health and anti-discrimination legislation, as well as by international conventions. However, the reproductive rights of women with HIV continue to be violated in public clinics and hospitals. This paper discusses three violations identified as priority problems by Mexican women with HIV, illustrating these problems with cases identified during a participatory skills building workshop. The violations cover the following rights: the right to non-discrimination, the right to adequate information and informed consent to medical procedures, and the right to choose the number and spacing of children. Physicians can either violate or promote reproductive rights. Unfortunately, in many instances Mexican physicians continue to perpetrate reproductive rights abuses against women with HIV. Collaborations between women with HIV, civil society, government, and international organizations are needed to educate and sanction health care providers and to support women with HIV in their pursuit of reproductive rights. Demanding accountability from health care practitioners and the State to guarantee reproductive rights in countries where these rights are formally protected will improve the quality of life of people with HIV and can demonstrate that rights-based approaches are compatible with and indeed, crucial for public health.

  5. Proceedings

    International Nuclear Information System (INIS)

    Jury, J.W. ed.

    1990-01-01

    These fifteen papers were presented by students in nuclear engineering from the Universities of Toronto and Manitoba, the Royal Military College, Ecole Polytechnique, McMaster University, and Trent University. They cover the areas of CANDU, SLOWPOKE and MAPLE reactor systems and fuel, applied nucleonics, and simulation theory and thermalhydraulics. (L.L.)

  6. Proceedings

    International Nuclear Information System (INIS)

    1997-01-01

    The 14. annual meeting of BIOMINET (Mineral and Energy Applied Biotechnology Network) and NCUT (National Centre for Upgrading Technology) took place on June 9, 1997 in Calgary, as part of the CIM Petroleum Society's 48. annual technical meeting. Papers presented at the meeting focused on the application of biotechnology to the fossil fuel industry. There were two sessions, one devoted to application of biotechnology to environmental concerns of the fossil fuel industry, the other emphasizing bioupgrading of petroleum feedstocks

  7. Proceedings

    International Nuclear Information System (INIS)

    1989-01-01

    This course reviewed the adverse effects of ionizing radiation on man, the development of radiation protection criteria and standards, the administrative structure required for radiation protection and the consequences of some major radiation accidents. Overviews were given of the technical requirements for occupational radiation protection and for controlling the impacts from uses of radionuclides. Presentations were made on regulations for the transport of radioactive materials and on international resources and agreements for radiation protection. Examples of the development of codes and guidelines for specific purposes were also given. Refs., figs., tabs

  8. Proceedings

    International Nuclear Information System (INIS)

    Lee, H.C.; Saharia, A.N.; Thomas, A.W.

    1979-12-01

    Invited talks presented at a two-week workshop on pion-nucleon interactions are briefly presented and a summary of the discussions that took place is added. Topics covered include quantum chromodynamics and the weak NNπ vertex, pionic effects in the weak decays of nuclei, the isobar-doorway approach to the pion-nucleus interaction, multiple scattering approaches, the phenomenology of non-elastic reactions within the isobar-doorway picture, a field theory of pion-nucleus interaction, and the quark structure of the nucleon in nuclei. (LL)

  9. Obesity and central adiposity in Mexican adults: results from the Mexican National Health and Nutrition Survey 2006 Obesidad y adiposidad central en adultos mexicanos: resultados de la Encuesta Nacional de Salud y Nutrición 2006

    OpenAIRE

    Simón Barquera; Ismael Campos-Nonato; Lucía Hernández-Barrera; Mario Flores; Ramón Durazo-Arvizu; Rebecca Kanter; Juan A Rivera

    2009-01-01

    OBJECTIVE: To estimate the prevalence of overweight, obesity and central adiposity in Mexico, and to explore trends compared to the previous Mexican National Health Survey (ENSA 2000) and to Mexican-Americans. MATERIAL AND METHODS: The Mexican National Health and Nutrition Survey 2006 (ENSANUT 2006) was used to describe overweight, obesity and central adiposity. Trends over time were assessed using the ENSA 2000 and by comparing the ENSANUT 2006 results to those of Mexican-Americans using the...

  10. Proceedings of the Second APEC Coal Flow Seminar Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-05

    This proceedings includes papers presented at the Second APEC Coal Flow Seminar held at Shanghai in December, 1995. Three keynote speeches were presented, and two panel discussions were held. `Medium-term outlook for coal trade,` `Energy and the environment,` and `Progress with environmental control technology and technical exchanges between economies` were presented as keynote speeches. In the panel discussions, `Achieving low environmental impact from coal production and utilization` and `How to tackle environmental issues related to coal` were discussed. The Panel 1 was divided into Part 1 and Part 2. In the Part 1, overview of current environmental protection policy measures was discussed in relation to coal production and use in economies where coal consumption has been increasing significantly. In the Part 2, overview of current environmental protection policy measures was discussed in relation to coal production and use in major coal producing and consuming economies. 38 refs., 64 figs., 31 tabs.

  11. Mexican and Mexican-American children's funds of knowledge as interventions into deficit thinking: opportunities for praxis in science education

    Science.gov (United States)

    Licona, Miguel M.

    2013-12-01

    In this case study, I use an ethnographic-style approach to understand the funds of knowledge of immigrant families living in colonias on both sides of the US/Mexico border. I focus on how these "knowledges" and concomitant experiences impact the ways we perceive and treat immigrant students who have all too often been viewed through deficit lenses that relegate them to the lowest expectations and outcomes in the classroom. I find that Mexican and Mexican-American families hold unusually sophisticated and relevant "knowledges" to mitigate their everyday lives. In this paper, I will refer to citizens of Mexico, whether they reside in Mexico or have crossed to the United States legally or without documentation for purposes of work, as Mexican. People who have crossed the border and are living in the US as legal residents or have gained citizenship are referred to as Mexican-Americans. They live a hybrid identity that is varied and dynamic, an issue that adds to the complexity of the content and contexts of this study. These families know and use these "knowledges" on a daily basis, yet they are not recognized by teachers in the US as a starting point to affirm and support immigrant children. Instead, immigrant children are relegated to the non-gifted and lower track classes where science is taught from an abstract and non-contextual and therefore less engaged basis. The approach I outline here, based on insights from my case study, can greatly improve teachers' abilities to prepare their curricula for diversity in science education and science literacy as well as for broad expectations for student success.

  12. Description of Mexican Cleft Surgeons' Experience With Foreign Surgical Volunteer Missions in Mexico.

    Science.gov (United States)

    Schoenbrunner, Anna R; Kelley, Kristen D; Buckstaff, Taylor; McIntyre, Joyce K; Sigler, Alicia; Gosman, Amanda A

    2018-05-01

    Mexican cleft surgeons provide multidisciplinary comprehensive cleft lip and palate care to children in Mexico. Many Mexican cleft surgeons have extensive experience with foreign, visiting surgeons. The purpose of this study was to characterize Mexican cleft surgeons' domestic and volunteer practice and to learn more about Mexican cleft surgeons' experience with visiting surgeons. A cross-sectional validated e-mail survey tool was sent to Mexican cleft surgeons through 2 Mexican plastic surgery societies and the Asociación Mexicana de Labio y Paladar Hendido y Anomalías Craneofaciales, the national cleft palate society that includes plastic and maxillofacial surgeons who specialize in cleft surgery. We utilized validated survey methodology, including neutral fact-based questions and repeated e-mails to survey nonresponders to maximize validity of statistical data; response rate was 30.6% (n = 81). Mexican cleft surgeons performed, on average, 37.7 primary palate repairs per year with an overall complication rate of 2.5%; 34.6% (n = 28) of respondents had direct experience with patients operated on by visiting surgeons; 53.6% of these respondents performed corrective surgery because of complications from visiting surgeons. Respondents rated 48% of the functional outcomes of visiting surgeons as "acceptable," whereas 43% rated aesthetic outcomes of visiting surgeons as "poor"; 73.3% of respondents were never paid for the corrective surgeries they performed. Thirty-three percent of Mexican cleft surgeons believe that there is a role for educational collaboration with visiting surgeons. Mexican cleft surgeons have a high volume of primary cleft palate repairs in their domestic practice with good outcomes. Visiting surgeons may play an important role in Mexican cleft care through educational collaborations that complement the strengths of Mexican cleft surgeons.

  13. Conference Proceedings: Profit through technology

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-31

    Advances in, and experiences with, horizontal well technology as one of the principal means of enhancing oil recovery were the themes that animated this international conference in Calgary, organized jointly by the Society of Petroleum Engineers (USA) and the Canadian Institute of Mining, Metallurgy and Petroleum. A total of 47 papers were selected for presentation by the Program Committee of the SPE on the basis of abstracts submitted by authors and these are included in this proceedings volume. Topics range from hydrajet fracturing through field implementation of geological steering techniques, sand control in open hole horizontal wells and improving water flooding efficiency, to steam assisted gravity drainage and chemical flooding through horizontal wells. A number of case histories are presented to illustrate technological advances. The case histories cover a wide range of applications and cover experiences from a number of countries. refs., tabs., figs.

  14. PCaPAC 2006 Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Pavel Chevtsov; Matthew Bickley (Eds.)

    2007-03-30

    The 6-th international PCaPAC (Personal Computers and Particle Accelerator Controls) workshop was held at Jefferson Lab, Newport News, Virginia, from October 24-27, 2006. The main objectives of the conference were to discuss the most important issues of the use of PCs and modern IT technologies for controls of accelerators and to give scientists, engineers, and technicians a forum to exchange the ideas on control problems and their solutions. The workshop consisted of plenary sessions and poster sessions. No parallel sessions were held.Totally, more than seventy oral and poster presentations as well as tutorials were made during the conference, on the basis of which about fifty papers were submitted by the authors and included in this publication. This printed version of the PCaPAC 2006 Proceedings is published at Jefferson Lab according to the decision of the PCaPAC International Program Committee of October 26, 2006.

  15. Procedural Justice in Dutch Administrative Court Proceedings

    Directory of Open Access Journals (Sweden)

    André Verburg

    2014-11-01

    Full Text Available In this paper we discuss recent developments in administrative court proceedings in the Netherlands, called the New Approach. Along with developments leading to the New Approach, it became clear that the insights from research on procedural justice deserve particular attention. The goals of the judge's actions in this respect are both that the proceedings are fair and just and that parties perceive the way they are being treated during proceedings as fair and just.Within the New Approach we discern five procedural justice elements: (1 respect, (2 voice and due consideration, (3 some influence on how proceedings will continue, (4 an explanation of how the proceedings will continue and (5 direct interpersonal contact.The introduction of the New Approach shows two important bottlenecks in Dutch administrative court proceedings, which are (i the possible or supposed collision between legally right outcomes and  procedural justice and (ii the lack of uniformity and predictability.Although what we describe and discuss in this paper focuses on the Dutch situation, many of these considerations apply to administrative court proceedings in other countries. The themes and difficulties that face the administrative law judge seem to be common to many countries.

  16. The Role of la Familia for Women of Mexican Descent Who Are Leaders in Higher Education

    Science.gov (United States)

    Elizondo, Sandra Gray

    2012-01-01

    The purpose of this qualitative case study was to describe the role of "la familia" for women of Mexican descent as it relates to their development as leaders and their leadership in academia. Purposeful sampling was utilized to reach the goal of 18 participants who were female academic leaders of Mexican descent teaching full time in…

  17. Effect of acculturation and mutuality on family loyalty among Mexican American caregivers of elders.

    Science.gov (United States)

    Kao, Hsueh-Fen S; An, Kyungeh

    2012-06-01

    Informal family care for elders is conventional in Mexican American communities despite increasing intergenerational gaps in filial values. In our study, we explored whether acculturation and dyadic mutuality, as perceived by Mexican American family caregivers, explain the caregivers' expectations of family loyalty toward elderly relatives. A nonexperimental, correlational design with convenience sampling was used in El Paso, Texas, from October 2007 to January 2008. Three bilingual promotoras collected data from 193 Mexican American adult caregivers of community-dwelling elders using three scales designed for Mexican Americans: the Acculturation Rating Scale for Mexican Americans II-Short Form, the Mutuality Scale, and the Expectations of Family Loyalty of Children Toward Elderly Relatives Scale. Confirmatory factor analysis was used to analyze the data. Acculturation had a marginal effect (r = .21, p loyalty toward elderly relatives. There was no significant correlation between acculturation and mutuality (r = .05). Although Mexican American caregivers with strong Mexican orientation may have high expectations of family loyalty toward elderly relatives, mutuality exhibits more significant effects on expectations. Among Mexican Americans, mutuality between the caregiving dyad, as perceived by caregivers, may be a better predictor of filial values than caregivers' acculturation alone. It may be useful to incorporate the dual paradigm of acculturation and mutuality into immigrant family care for elderly relatives. © 2012 Sigma Theta Tau International.

  18. The Relation between Maternal and Child Depression in Mexican American Families

    Science.gov (United States)

    Corona, Marissa; McCarty, Carolyn; Cauce, Ana Mari; Robins, Richard W.; Widaman, Keith F.; Conger, Rand D.

    2012-01-01

    In an effort to better understand possible pathways that lead to a relatively high incidence of depressive symptoms among Mexican American youth, an interpersonal stress model of depression was tested using a community sample of 674 Mexican American mothers and their 5th grade children. Structural equation analyses revealed that maternal…

  19. An Anthropology of "Familismo": On Narratives and Description of Mexican/Immigrants

    Science.gov (United States)

    Smith-Morris, Carolyn; Morales-Campos, Daisy; Alvarez, Edith Alejandra Castaneda; Turner, Matthew

    2013-01-01

    Research on core cultural values has been central to behavioral and clinical research in ethnic groups. "Familismo" is one such construct, theorized as the strong identification and attachment of Hispanic persons with their nuclear and extended families. Our anthropological research on this concept among Mexicans and Mexican immigrants in the…

  20. Conflict Resolution in Mexican-Origin Couples: Culture, Gender, and Marital Quality

    Science.gov (United States)

    Wheeler, Lorey A.; Updegraff, Kimberly A.; Thayer, Shawna M.

    2010-01-01

    This study examined associations between Mexican-origin spouses' conflict resolution strategies (i.e., nonconfrontation, solution orientation, and control) and (a) gender-typed qualities and attitudes, (b) cultural orientations, and (c) marital quality in a sample of 227 couples. Results of multilevel modeling revealed that Mexican cultural…