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A novel series of copolymers were obtained from the copolymerization of 1-ethynylpyrene (EP) (known as pyrenylacetylene) and ethynylbenzene (EB) (named also phenylacetylene) with WCl6 as catalyst and toluene as solvent, using different monomer molar ratios EP/EB (80:20, 60:40, 50:50; 40:60, 20:80). The optical properties of the obtained copolymers Poly(EP-co-EB) were determined by absorption and fluorescence spectroscopy. Absorption spectra of the copolymers Poly(EP-co-EB) showed that copolymers containing phenylacetylene units possess a lower degree of conjugation than the homopolymer trans-poly(1-ethynylpyrene) (trans-PEP), since they showed a twisted conformation. These results were confirmed by emission spectroscopy showing the formation of excimers for those copolymers containing high pyrene content.
To summarise the findings from this supplemental issue on the distribution of malnutrition (stunting/short stature, anaemia and overweight) by wealth, education and ethnicity within and between ten Latin American countries.
We retrieved information from each country’s article and estimated the average difference in the prevalence of malnutrition between groups. We estimated the associations between countries’ malnutrition prevalence and GDP, percentage of women with high education and percentage of non-indigenous ethnicity.
Nationally representative surveys from ten Latin American countries conducted between 2005 and 2017.
Children (<5 years), adolescent women (11–19 years) and adult women (20–49 years).
Socially disadvantaged groups (low wealth, low education and indigenous ethnicity) had on average 15–21 (range across indicators and age groups) percentage points (pp) higher prevalence of stunting/short stature and 3–11 pp higher prevalence of anaemia. For overweight or obesity, adult women with low education had a 17 pp higher prevalence; differences were small among children <5 years, and results varied by country for adolescents by education, and for adults and adolescents by wealth and ethnicity. A moderate and strong correlation (–0·58 and –0·71) was only found between stunting/short stature prevalence and countries’ GDP per capita and percentage of non-indigenous households.
Overweight was equally distributed among children; findings were mixed for ethnicity and wealth, whereas education was a protective factor among adult women. There is an urgent need to address the deep inequalities in undernutrition and prevent the emerging inequalities in excess weight from developing further.
Darwin's frogs Rhinoderma darwinii and Rhinoderma rufum are the only known species of amphibians in which males brood their offspring in their vocal sacs. We propose these frogs as flagship species for the conservation of the Austral temperate forests of Chile and Argentina. This recommendation forms part of the vision of the Binational Conservation Strategy for Darwin's Frogs, which was launched in 2018. The strategy is a conservation initiative led by the IUCN SSC Amphibian Specialist Group, which in 2017 convened 30 governmental, non-profit and private organizations from Chile, Argentina and elsewhere. Darwin's frogs are iconic examples of the global amphibian conservation crisis: R. rufum is categorized as Critically Endangered (Possibly Extinct) on the IUCN Red List, and R. darwinii as Endangered. Here we articulate the conservation planning process that led to the development of the conservation strategy for these species and present its main findings and recommendations. Using an evidence-based approach, the Binational Conservation Strategy for Darwin's Frogs contains a comprehensive status review of Rhinoderma spp., including critical threat analyses, and proposes 39 prioritized conservation actions. Its goal is that by 2028, key information gaps on Rhinoderma spp. will be filled, the main threats to these species will be reduced, and financial, legal and societal support will have been achieved. The strategy is a multi-disciplinary, transnational endeavour aimed at ensuring the long-term viability of these unique frogs and their particular habitat.
OBJECTIVES/GOALS: To assess the impact of FLTCs on CTR on S and F from health professions and basic science academic programs island wide in Puerto Rico. Cycles supported by the Title V Cooperative Project at University of Puerto Rico-Medical Sciences Campus (UPRMSC) and Universidad Central del Caribe (UCC)(Title V). METHODS/STUDY POPULATION: After offering FLTCs in CTR to S and F from UPRMSC and UCC, Title V expanded it to S and F from other institutions island wide in PR. These FLTCs were offered the 2nd semester of 2018 and consisted of 20 hours of interdisciplinary sessions in: introduction to and definition of CTR; preparation of a CTR-presentation; how to interview/share a presentation of a CT researcher and to prepare a research question in CTR. To assess the knowledge of S and F in the above-mentioned skills and their continuation in the 2nd level of CTR training, surveys were administered: pre-test, at the beginning, post-test, sometime during the FLTCs, and satisfaction at the end of the FLTCs. RESULTS/ANTICIPATED RESULTS: Fifty eight (58) S/F from UPRMSC, UCC and 7 other institutions participated. Forty two (42,72%) answered a pre-test and 31/42 (74%) completed the post-test. Results showed that S/F: who correctly defined CTR increased from 7% to 77 %; their ability to identify a CT researcher increased from 10% to 83%. Fifty five percent (55 %) (21/38) S/F that were certified in the FLTCs, answered the satisfaction survey. One hundred percent (100%) indicated that the materials offered contributed in the identification of a CT researcher and a topic in CTR; 100% answered that the FLTCs contributed higher knowledge in and provided new skills in CTR. Moreover, 31/38 (82%) S/F started the 2nd level of training. DISCUSSION/SIGNIFICANCE OF IMPACT: The FLTCs were successful in increasing S/F knowledge of CTR and to further engage in 2nd level of trainings. Title V impact extended island wide, increasing the diversity of represented health professions and science fields among participants. The interventions were deemed to be of high quality.
To compare the prevalence of malnutrition (undernutrition and excess weight) by wealth, education level, ethnicity and urban/rural areas in Mexican children and women of reproductive age.
We compared the prevalence of overweight, obesity, wasting/underweight, stunting/short stature and anaemia by socioeconomic and ethnic indicators. For each indicator, we estimated prevalence ratios (PR) adjusted by all other socioeconomic and ethnic indicators. We analysed if results differed by urban/rural areas.
Mexican National Health and Nutrition Survey 2012.
Children <5 years, non-pregnant women 11–19 years and non-pregnant women 20–49 years (n 33 244).
In most age groups, belonging to non-indigenous households, with high wealth, high education and in urban areas were inversely associated with stunting or short stature (PR ranging from 0·40 to 0·83), and wealth and education were inversely associated with anaemia (PR ranging from 0·53 to 0·78). The prevalence of overweight was similar across subgroups among children <5 years; however, among women 11–19 years, wealth, non-indigenous household and urban areas were positively associated (PR ranging from 1·16 to 1·33); and among women 20–49 years, education was inversely associated (PR 0·83).
Socially disadvantaged populations have a higher prevalence of undernutrition, whereas the prevalence of excess weight is either equal (children <5 years), slightly lower (women 11–19 years) or even higher (women 20–49 years) with lower education. These results highlight the need for specific actions to address social inequalities in malnutrition in the Mexican population.
The promotion of water consumption has been identified by the government of Mexico as one of the main strategies to reduce the diet energy density in order to prevent the problems of overweight, obesity and other diseases. The aim of the present study was to determine the correlation of the water consumption with nutritional status, metabolic risk and percentage of body fat in adults of Mexico City. A sample of 12733 adults residing in Mexico City was obtained, of which 75.6% (n = 9 623) belongs to the female gender and 24.4% (n = 3110) belongs to the male gender. In the study those adults who were between 21 and 60 years old, with an average age of 39.59 ± 10.97 years, were included. The population was constituted in several health fairs celebrated in Mexico City from 2015–2018, in which nutritional consultation was provided. By correlating water consumption with nutritional status, metabolic risk and percentage of body fat, it was found that adults who consume a glass of water of 250 mL per day, have higher incidence of obesity, metabolic risk and percentage of body fat high (70.0%, 83.6% and 96.2, respectively), compared to adults who consume seven glasses of 250 mL of water per day equivalent to 1750 mL of water per day (40.4%, 63.8% and 92.9, respectively), finding a highly significant difference (p < 0.01). In the present study it can be observed that adults who have optimal water intake have a lower incidence of obesity, metabolic risk and high percentage of body fat, data that agree with the literature. However, despite the fact that the multiple benefits of water intake have been documented, its consumption among the population in general is very low, so it is suggested to continue adding efforts to raise awareness among the population regarding the importance and benefits on health by staying well hydrated. Likewise, it is important to consider that the promotion of water consumption is an important component in strategies to promote healthy habits and lifestyles.
TwinsMX is a national twin registry in Mexico recently created with institutional support from the Universidad Nacional Autónoma de México. It aims to serve as a platform to advance epidemiological and genetic research in the country and to disentangle the genetic and environmental contributions to health and disease in the admixed Mexican population. Here, we describe our recruitment and data collection strategies and discuss both the progress to date and future directions. More information about the registry is available on our website: https://twinsmxofficial.unam.mx/ (content in Spanish).
To determine the prevalence of low scores for two neuropsychological tests with five total scores that evaluate learning and memory functions.
N = 5402 healthy adults from 11 countries in Latin America and the commonwealth of Puerto Rico were administered the Rey–Osterrieth Complex Figure (ROCF) and the Hopkins Verbal Learning Test (HVLT-R). Two-thirds of the participants were women, and the average age was 53.5 ± 20.0 years. Z-scores were calculated for ROCF Copy and Memory scores and HVLT-R Total Recall, Delayed Recall, and Recognition scores, adjusting for age, age2, sex, education, and interaction variables if significant for the given country. Each Z-score was converted to a percentile for each of the five subtest scores. Each participant was categorized based on his/her number of low scoring tests in specific percentile cutoff groups (25th, 16th, 10th, 5th, and 2nd).
Between 57.3% (El Salvador) and 64.6% (Bolivia) of the sample scored below the 25th percentile on at least one of the five scores. Between 27.1% (El Salvador) and 33.9% (Puerto Rico) scored below the 10th percentile on at least one of the five subtests. Between 5.9% (Chile, El Salvador, Peru) and 10.3% (Argentina) scored below the 2nd percentile on at least one of the five scores.
Results are consistent with other studies that found that low scores are common when multiple neuropsychological outcomes are evaluated in healthy individuals. Clinicians should consider the higher probability of low scores when evaluating learning and memory using various sets of scores to reduce false-positive diagnoses of cognitive deficits.
OBJECTIVES/SPECIFIC AIMS: The Title V Cooperative Project of the UPR-MSC and UCC has demonstrated that educational interventions in CTR are very effective in fulfilling the objective of promoting awareness, stimulate interest and increase the knowledge, skills and opportunities, to US, GS and F (participants) in CTR. METHODS/STUDY POPULATION: The training sessions (TS) offered through the Title V initiative have become an engine for the involvement in CTR for participants from higher education institutions island-wide. TS consisted of cycles –level 1 and 2–: Research Education Towards Opportunities (RETO,I,II) and Mentorship Offering Training Opportunities for Research (MOTOR,I,II), ending in the formation of the Clinical and Translational Mentoring Teams (CTMT)s, in which participants, paired by their research interests, were mentored by a well-established CT researchers in their research project, to be developed in the Intensive Development and Experiences in Advancement of Research and Increased Opportunities (IDEARIO). RESULTS/ANTICIPATED RESULTS: Up to date, 4 TS-level 1 and 2 TS-level 2 were offered. Eighty (80) participants completed level 1, distributed: 42 (52.5%) US in RETO, 21 (26.25%) GS and 17 (21.25%) F in MOTOR and 17 participants completed level 2, distributed: 4 (23.52%) US in RETO, 6 (25.29%) GS and 7 (41.17%) F in MOTOR. From which, 15, with 8 CT researchers, formed 5 CTMTs in different research areas – cardio, neuro, liver, renal, Zika–. DISCUSSION/SIGNIFICANCE OF IMPACT: US, GS and F were integrated in the active process throughout educational levels for their development in CTR.
Cryptococcal Meningitis is a fungal infectious disease of worldwide distribution, primarily associated with underlying immunosuppression conditions such as HIV infection, glucocorticoid treatment, status post organ transplantation and oncological treatments. Prevalence is particularly high in third-world countries where it constitutes one of the primary causes of central nervous system infections and may carry fatal outcomes. We present two cases of Cryptococcal Meningitis that portray the vast spectrum of clinical presentations associated with Cryptococcal Meningitis as well as relevant diagnostic and therapeutic implications.
Case study - These adult otherwise healthy patients presented at a public urban university hospital in southern Colombia. Both had an unusual clinical course and suffered fatal outcomes despite being seemingly immunocompetent at baseline. A diagnosis of hepatic cirrhosis could have been considered a cause of immunosuppression in one of the patients and the diagnostic work-up for the other patient revealed no evidence of immunological deficiency.
Cryptococcal Meningitis affecting immunocompetent individuals has been increasingly reported in recent years. Furthermore, outcomes in this population are particularly worse than those generally affected by the disease. A review of the literature related to the possible immunological mechanisms’ underlying the presented clinical course is included. We emphasize the importance of considering Cryptococcus spp. as a possible etiologic agent among differential diagnoses upon encountering suggestive meningeal conditions in immunocompetent patients.
To estimate changes in taxed and untaxed beverages by volume of beverage purchased after a sugar-sweetened beverage (SSB) tax was introduced in 2014 in Mexico.
We used household purchase data from January 2012 to December 2015. We first classified the sample into four groups based on pre-tax purchases of beverages: (i) higher purchases of taxed beverages and lower purchases of untaxed beverages (HTLU-unhealthier); (ii) higher purchases of both types of beverages (HTHU); (iii) lower purchases of taxed and untaxed beverages (LTLU); and (iv) lower purchases of taxed beverages and higher purchases of untaxed beverages (LTHU-healthier). Next, we estimated differences in purchases after the tax was implemented for each group compared with a counterfactual based on pre-tax trends using a fixed-effects model.
Areas with more than 50 000 residents in Mexico.
Households (n 6089).
The HTLU-unhealthier and HTHU groups had the largest absolute and relative reductions in taxed beverages and increased their purchases of untaxed beverages. Households with lower purchases of untaxed beverages (HTLU-unhealthier and LTLU) had the largest absolute and relative increases in untaxed beverages. We also found that among households with higher purchases of taxed beverages, the group with lowest socio-economic status had the greatest reduction in purchases of taxed beverages.
Evidence associating the SSB tax with larger reductions among high purchasers of taxed beverages prior to the tax is relevant, as higher SSB purchasers have a greater risk of obesity, diabetes and other cardiometabolic outcomes.
Childhood obesity has increased rapidly in Mexico, along with changes in the food environment. However, little is known about the dietary patterns (DP) of Mexican children. We aimed to characterize the DP of schoolchildren and to analyse their associations with sociodemographic factors.
Cross-sectional analysis. Dietary and sociodemographic information was obtained, including a single 24 h recall, socio-economic status (SES), geographic region, area of residence and ethnicity. DP were defined with cluster analysis (using k-means). Multinomial logistic regression models, adjusted for the survey design, were used to assess associations between DP and sociodemographic variables.
2012 Mexican National Health and Nutrition Survey (ENSANUT-2012).
Schoolchildren (n 2751) aged 5–11 years who participated in ENSANUT-2012.
Four DP were identified: ‘Traditional’, ‘Industrialized’, ‘Varied’ and ‘Modern’. Reported energy intake (mean (sd)) was lowest in the ‘Traditional’ and highest in the ‘Industrialized’ DP (7037 (3707) kJ/d (1682 (886) kcal/d) v. 8427 (3753) kJ/d (2014 (897) kcal/d), respectively, P<0·05). Significant differences in fat and fibre intakes were seen across DP. Non-indigenous v. indigenous children were 22·0 times (95 % CI 5·1, 93·6) more likely to have a ‘Modern’ rather than ‘Traditional’ DP. Relative likelihood of having an ‘Industrialized’ rather than ‘Traditional’ DP was 6·2 (95 % CI 3·9, 9·9) among schoolchildren from high SES v. low SES.
Among Mexican schoolchildren, DP were associated with sociodemographic variables. Non-indigenous children were significantly more likely to consume a ‘Modern’ than a ‘Traditional’ DP. Children with higher SES were more likely to have an ‘Industrialized’ pattern. It is necessary to consider dietary characteristics in the different sociodemographic strata when dietary interventions are designed.
We study ultrametric germs in one variable having an irrationally indifferent fixed point at the origin with a prescribed multiplier. We show that for many values of the multiplier, the cycles in the unit disk of the corresponding monic quadratic polynomial are ‘optimal’ in the following sense: they minimize the distance to the origin among cycles of the same minimal period of normalized germs having an irrationally indifferent fixed point at the origin with the same multiplier. We also give examples of multipliers for which the corresponding quadratic polynomial does not have optimal cycles. In those cases we exhibit a higher-degree polynomial such that all of its cycles are optimal. The proof of these results reveals a connection between the geometric location of periodic points of ultrametric power series and the lower ramification numbers of wildly ramified field automorphisms. We also give an extension of Sen’s theorem on wildly ramified field automorphisms, and a characterization of minimally ramified power series in terms of the iterative residue.
A two-dimensional global stability analysis is numerically conducted for the basic fully developed steady flow inside symmetric wavy channels. The relative amplitude of channel modulation, defined as ratio of wall modulation amplitude to mean hydraulic diameter, is fixed via the analysis at a large value of 0.15. The relative channel wavelength, defined as the ratio of wall modulation wavelength to mean hydraulic diameter, is varied between 1 and 5. An important feature of the present approach is the detailed consideration of the streamwise conditions imposed on the flow, which allows a tailored restriction of the possible disturbances by modifying the number of channel sections that set the periodicity. Stability of the base flow is determined on the basis of the spectral structure analysis conducted, possible after calculation of the complete eigenvalue spectrum and facilitated by the spectral method employed. Two different destabilization mechanisms have been identified for the geometry studied. For small relative channel wavelengths, with values below approximately 2.7, the flow is destabilized via a Hopf bifurcation produced by a Tollmien–Schlichting wave at Reynolds numbers in the approximated range from 265 to 324. For large relative channel wavelengths, with values above approximately 2.5, a pitchfork bifurcation (or a Hopf bifurcation with very small oscillation frequency), not previously reported in the literature and produced by a symmetric stationary disturbance, is found at Reynolds numbers in the approximated range from 146 to 230.
The endocannabinoids anandamide and 2-arachidonyl glycerol (2-AG) are modulators of glutamate and γ-aminobutyric acid (GABA), two transmitters involved in cocaine addiction. However, little is known on the effects of cocaine on the enzymes that produce and degrade endocannabinoids. The present work addresses the effects of cocaine self-administration on the immunohistochemical expression of endocannabinoid signalling (ECS)-related proteins in the hippocampus. The study has been performed on two different strains of rats, Lewis (Lew) and Fischer 344 (F344), which are characterized for displaying a differential sensitivity to cocaine, thus making them suitable in the study of vulnerability to drug addiction. Both strains showed differences in the expression of ECS-related proteins in the hippocampus, i.e. Lew rats exhibited lower CB1 expression but higher CB2 expression than F344 rats. After setting similar cocaine self-administration, both strains showed clear differences in the expression of ECS-related proteins, which were differentially restricted to either the 2-AG or anandamide signalling pathways in a self-administration training/drug-dependent manner. The decreases observed in CB1 expression and N-acyl phosphatidylethanolamine phospholipase D:fatty acid amino hydrolase ratio after saline self-administration were enhanced only in cocaine self-administered Lew rats. CB2 expression increase and diacylglycerol lipase α:monoacylglycerol lipase ratio decrease detected after saline self-administration were blocked only in cocaine self-administered F344 rats. These findings indicate that cocaine may regulate hippocampal GABA/glutamate synapses by directly modulating endocannabinoid production/degradation enzymes and that these actions are strain-dependent. This differential response suggests that the endogenous cannabinoid system might contribute to genotype/strain differences on the sensitivity to self-administration training and cocaine addiction.
Among the many challenges to deal with, when a robot is interacting with its environment, friction at the contact surface and/or at the joints is one of the most important to be considered. In this paper we propose a control algorithm for the tracking of position and force (unconstrained orientation case only) of a manipulator end-effector that does not require the robot model for implementation. This characteristic has the advantage of making it capable to compensate friction effects without any previous estimation. Furthermore, no velocity measurements are needed, and the unit quaternion is employed for orientation control. Experimental and simulation results are provided.
To investigate the relationship between dietary patterns and self-perceived body shape silhouette and BMI in a sample of Mexican women.
A cross-sectional analysis of dietary habits from baseline data of a large cohort study (EsMaestra) conducted in 2006–2008.
The state of Veracruz, Mexico.
Mexican teachers (n 20 330) provided information on body shape silhouette at baseline, changes in body shape silhouette and BMI, as well as information on sociodemographic variables and lifestyle.
The median BMI was 26·8 kg/m2; 43 % of women were overweight and 24 % were obese. The carbohydrates, sweet drinks and refined foods pattern was associated with a greater risk of having a large silhouette and a large BMI (BMI ≥ 30·0 kg/m2v. BMI < 25·0 kg/m2; ORT1−3 = 1·86, 95 % CI 1·56, 2·22 and 1·47, 95 % CI 1·28, 1·69, respectively) with a significant trend when comparing the first and third tertiles of intake. The fruit and vegetable pattern was associated with a lower risk of having a large silhouette and a large BMI (ORT1−3 = 0·68, 95 % CI 0·57, 0·82 and ORT1−3 = 0·77, 95 % CI 0·67, 0·88, respectively) with a significant decreasing trend. Similar results were observed when change in silhouette (from 18 years of age to current silhouette) was considered.
High intakes of carbohydrates, sweet drinks and refined foods are related to larger silhouettes. Public health intervention improving access to healthy dietary guidelines, healthy food choice in the work place, promotion of physical activity and regulation of beverages with a high sugar content and of refined foods should be considered.
We show some level-2 large deviation principles for rational maps satisfying a strong form of non-uniform hyperbolicity, called ‘Topological Collet–Eckmann’. More precisely, we prove a large deviation principle for the distribution of iterated preimages, periodic points, and Birkhoff averages. For this purpose we show that each Hölder continuous potential admits a unique equilibrium state, and that the pressure function can be characterized in terms of iterated preimages, periodic points, and Birkhoff averages. Then we use a variant of a general result of Kifer.