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Serum levels of undercarboxylated osteocalcin are related to cardiovascular risk factors in patients with type 2 diabetes mellitus and healthy subjects 被引量:6
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作者 Sergio Sanchez-Enriquez Isabel Thalia Ballesteros-Gonzalez +8 位作者 JoséRafael Villafán-Bernal Sara Pascoe-Gonzalez Edgar Alfonso Rivera-Leon Blanca Estela Bastidas-Ramirez Jorge David Rivas-Carrillo Juan Luis Alcala-Zermeno Juan Armendariz-Borunda Iris Monserrat Llamas-Covarrubias Abraham Zepeda-Moreno 《World Journal of Diabetes》 SCIE CAS 2017年第1期11-17,共7页
AIM To determine a potential relationship between serum undercarboxylated(uc OC) concentration and cardiovascular risk factors in type 2 diabetes(T2D) patients and healthy subjects(HS).METHODS A cross-sectional study ... AIM To determine a potential relationship between serum undercarboxylated(uc OC) concentration and cardiovascular risk factors in type 2 diabetes(T2D) patients and healthy subjects(HS).METHODS A cross-sectional study was conducted on 140 subjects classified into two groups, 70 with T2D and 70 HS. Medical history and physical examination with anthropometric measurements were obtained from all subjects. Body fat percentage was determined by bioelectrical impendency analysis. Serum uc OC concentration was determined by enzyme immunoassay,while serum levels of insulin and hsC RP were obtained using high sensitivity enzyme-linked immunosorbent assay. Insulin resistance was determined using the homeostasis model assessment-IR. Lipid profile [triglycerides,total cholesterol(TC), high-density lipoproteins(HDL-c),low density lipoproteins(LDL-c), very low-density lipoproteins] was determined by spectrophotometry and standard formulas when applicable. RESULTS The T2D patient group showed significantly higher values of waist circumference, waist-to-hip ratio, systolic blood pressure(SBP), diastolic blood pressure(DBP),current smoking, and alcohol use when compared to the HS group(P < 0.05). We observed a significantly lower serum ucO C concentration in T2D than in HS(1.5 ± 1.4vs 2.3 ± 1.8, P < 0.05). In the whole study population,ucO C concentration was inversely correlated with body mass index(BMI)(r =-0.236, P < 0.05), fasting plasma glucose(r =-0.283, P < 0.01) and HDL-c(r =-0.255,P < 0.05); and positively correlated with LDL-c/HDL-c ratio(r = 0.306, P < 0.05) and TC/HDL-c ratio(r =0.284, P < 0.05). In the T2D group, serum uc OC concentration was inversely correlated with BMI(r =-0.310, P < 0.05) and body-fat percentage(r =-0.311,P < 0.05), and positively correlated with DBP(r = 0.450,P < 0.01). In HS group a positive correlation between serum levels of uc OC and SBP(r = 0.277, P < 0.05)was observed. CONCLUSION Serum uc OC is a potential marker for cardiovascular risk in Mexicans because it is related to adiposity parameters, blood pressure and lipid profile. 展开更多
关键词 骨头 OSTEOCALCIN 葡萄糖新陈代谢 糖尿病 心血管的风险
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Noisy environments:untangling the role of anthropogenic noise on bird species richness in a Neotropical city 被引量:1
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作者 Cecilia Odette Carral-Murrieta Michelle Garcia-Arroyo +2 位作者 Oscar H.Marin-Gomez J.Roberto Sosa-Lopez Ian MacGregor-Fors 《Avian Research》 CSCD 2020年第3期258-264,共7页
Background:Among urban stimuli,anthropogenic noise has been identified to be one of the behavioral drivers of species that rely on acoustic signals for communication.Studies have shown both species‑specific and assemb... Background:Among urban stimuli,anthropogenic noise has been identified to be one of the behavioral drivers of species that rely on acoustic signals for communication.Studies have shown both species‑specific and assemblage responses to urban noise,ranging from the modulation of their acoustic frequencies and spatiotemporal adjustments to declines in species richness.In this study,we assessed the citywide relationship between two anthropogenic noise variables(noise levels recorded during bird surveys and daily average noise levels)and vegetation cover with bird species richness.Methods:This study was conducted in the city of Xalapa(Mexico)through a 114 citywide point‑count survey.We recorded bird communities at each sampling site.We measured noise levels using a sound level meter while performing point‑counts.Then,we generated a map of average daily noise of the city using an array of 61 autonomous recording units distributed across the city of Xalapa and calculated daily noise levels for the 114 points.We ran a linear model(LM)to assess potential relationships between both point‑count and daily(24 h)noise values and vegetation cover with bird richness.Results:Results from the LM show:(1)a negative relationship between maximum point‑count noise and avian species richness,(2)no relationship between 24 h noise and bird species richness,and(3)a positive relationship between vegetation cover and bird species richness.Conclusions:Results provide evidence that decreases in urban bird species richness do not necessarily imply the permanent absence of species,suggesting that birds can temporarily fly away from or avoid sites when noisy,become cryptic while noisy events are occurring,or be undetected due to our inability to record them in the field during noisy events. 展开更多
关键词 Avian ecology Bird communication Noise pollution Species richness Urban ecology
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Assessing above-ground biomass-functional diversity relationships in temperate forests in northern Mexico
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作者 Benedicto Vargas-Larreta Jorge Omar López-Martínez +2 位作者 Edgar J.González JoséJavier Corral-Rivas Francisco Javier Hernández 《Forest Ecosystems》 SCIE CSCD 2021年第1期95-108,共14页
Background:Studies on the relationship between biodiversity and ecosystem productivity have suggested that species richness and functional diversity are the main drivers of ecosystem processes.Several patterns on this... Background:Studies on the relationship between biodiversity and ecosystem productivity have suggested that species richness and functional diversity are the main drivers of ecosystem processes.Several patterns on this relationship have been found,including positive,unimodal,negative,and neutral trends,keeping the issue controversial.In this study,taxonomic diversity and functional diversity as drivers of above-ground biomass(AGB)were compared,and the mechanisms that influence biomass production were investigated by testing the complementarity and the mass-ratio hypotheses.Methods:Using data from 414 permanent sample plots,covering 23%of temperate forest in the Sierra Madre Oriental(México),we estimated the above-gound biomass(AGB),taxonomic and functional diversity indices,as well as community weighted mean values(CWM)for three functional traits(maximum height,leaf size and wood density)for trees≥7.5 cm DBH,in managed and unmanaged stands.To compare taxonomic diversity differences between managed and unmanaged stands we carried out a rarefaction analysis.Furthermore,we evaluated the relationship between AGB and taxonomic and functional diversity metrics,as well as CWM traits throught spatial autoregressive models.Results:We found a hump-shaped relationship between AGB and species richness in managed and unmanaged forests.CMW of maximum height was the most important predictor of AGB in both stands,which suggested that the mechanism underlaying the AGB-diversity relationship is the dominance of some highly productive species,supporting the mass-ratio hypothesis.Above-ground biomass was significantly correlated with three of the five functional diversity metrics,CWM maximum height and species richness.Our results show the importance of taking into account spatial autocorrelation in the construction of predictive models to avoid spurious patterns in the AGBdiversity relationship.Conclusion:Species richness,maximum height,functional richness,functional dispersion and RaoQ indices relate with above-ground biomass production in temperate mixed-species and uneven-aged forests of northern Mexico.These forests show a hump-shaped AGB-species richness relationship.Functional diversity explains better AGB production than classical taxonomic diversity.Community weighted mean traits provide key information to explain stand biomass in these forests,where maximum tree height seems to be a more suitable trait for understanding the biomass accumulation process in these ecosystems.Although the impact of forest management on biodiversity is still debated,it has not changed the AGB-diversity relationships in the forests of the Sierra Madre Occidental,Mexico. 展开更多
关键词 Taxonomic diversity Functional diversity Complementarity hypothesis Mass-ratio hypothesis
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Numerical Study of Highly Nonlinear Photonic Crystal Fiber with Tunable Zero Dispersion Wavelengths
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作者 Alejandro Barrientos García Igor A. Sukhoivanov +4 位作者 José Amparo Andrade Lucio Oscar Gerardo Ibarra Manzano Igor Guryev Juan Carlos Hernández García Gabriel Ramos Ortiz 《Journal of Electromagnetic Analysis and Applications》 2015年第5期141-151,共11页
Solid-core silica photonic crystal fiber is proposed borrowing the concept of golden ratio (1.618) and keeping it between pitch and air hole diameter Λ/d in a subset of six rings of air-holes with hexagonal arrangeme... Solid-core silica photonic crystal fiber is proposed borrowing the concept of golden ratio (1.618) and keeping it between pitch and air hole diameter Λ/d in a subset of six rings of air-holes with hexagonal arrangement. In the case when we have a pitch equal to one micron (Λ = 1 μm), we need air-holes diameters d = 0.618 μm in order to achieve two zero dispersion wavelength (ZDW) points at 725 nm and 1055 nm;this gives us the possibility to use the fiber for supercontinuum generation, by pumping close to that points, pulse compression or reshaping. We analyzed a series of fibers using this relation and showed the possibilities of tunable ZDW in a wide range of wavelengths from 725 nm to 2000 nm, with low losses and small effective area. In agreement with the ZDW point needed, the geometry of the structure can be modified to the point of having only three rings of air holes that surround the solid core with low losses and good confinement mode. The design proposed here is analyzed using the finite element method with perfectly matched layers, including the material dispersion directly into the model applying the Sellmeier’s equation. 展开更多
关键词 Photonic Crystal Fibers SUPERCONTINUUM Generation ZERO DISPERSION WAVELENGTH
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The Role of Health Inequality in the Maternal Health Services Provided by Public Institutions in Mexico
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作者 Graciela Freyermuth-Enciso Mónica Carrasco-Gómez Martín Romero-Martínez 《Health》 CAS 2016年第3期206-218,共13页
This work aims to determine the role of inequality in the provision of maternal health services among five regions in Mexico (northwest, northeast, central, the Mexico City-State of Mexico region and the south). We co... This work aims to determine the role of inequality in the provision of maternal health services among five regions in Mexico (northwest, northeast, central, the Mexico City-State of Mexico region and the south). We consider the most important service providers corresponding to the main health institutions in Mexico (IMSS, ISSSTE, SESAS, IMSS-Oportunidades). Therefore, a cross-sectional prospective study was conducted to analyze eight intervention packages (Prenatal Care, Syphilis, Influenza, Obstetric Urgent Care, HIV in pregnancy, delivery care, neonatal care and accessibility) offered by the Maternal and Perinatal Health (MPH) program. A quantitative analysis demonstrates low to marginal performance of the MPH program in three regions (South, Mexico City-State of Mexico and the Northwest) and marginal in two other regions (Central and Northeast). Furthermore, four of the intervention packages presented the lowest performance in the South (Prenatal Care, Syphilis, Influenza and Obstetric Urgent Care), as did the average of the total of the MPH packages. The performance of HIV in Pregnancy package was marginal in the Southern and Mexico City-State of Mexico regions and Neonatal Care was low in the Northwest. The assessment of the MPH intervention packages allows us to identify their strengths and weaknesses. This information allows us to identify similarities and differences among the geographical regions in order to describe and analyze the strengths, weaknesses, opportunities and threats in the current system and hence to improve the decision making regarding the Maternal and Perinatal Health Programs in Mexico. The results suggest that a homogenization has taken place in terms of the low quality of the services. 展开更多
关键词 Health Inequality Evaluation of Health Services Maternal and Perinatal Health Quality of Care
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Lead-Free Piezoelectric Ceramics as Candidates on the Development of Morphing Winglets in Aircrafts
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作者 Kevin Jiménez Guillermo Herrera 《材料科学与工程(中英文A版)》 2018年第1期32-42,共11页
In this paper we discussed the development of a morphing wingtip device or winglet for aircraft.The aim of this research is enhancing the aerodynamic of aircrafts,by optimizing the winglet shape,angle and torsion,to r... In this paper we discussed the development of a morphing wingtip device or winglet for aircraft.The aim of this research is enhancing the aerodynamic of aircrafts,by optimizing the winglet shape,angle and torsion,to reduce wingtip vortices at each flight stage,reduce drag,fuel consumption and increase its endurance.The development of a working physical wingtip device with morphing functionality,is possible by using piezoelectric MFCs(Macro Fiber Composites)as actuators in wing structures.Due to their excellent properties like flexibility,light weight,tolerant to damage and long term stability MFC fit most of the requirements and specifications of morphing structures.Unfortunately,they are based on the toxic compound of PbZrxTi1-xO3(PZT).Lead-free materials can replace lead based compounds.Also,other aim of this inquiry is the development of piezoelectric lead-free compounds based on the solid solution Ba1-xCaxTi0.9Zr0.1O3(BCZT)with x=0.1,0.125,0.15.The reason for choosing these compositions is because BZCT compounds could reach a piezoelectricity coefficient d33~400 pC/N.This value is comparable with commercial PZT,therefore it is a great candidate to replace it. 展开更多
关键词 PIEZOELECTRIC MORPHING PLANE MFCs VORTICES winglet.
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Nightlife in the city: drivers of the occurrence and vocal activity of a tropical owl
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作者 Oscar Humberto Marín‑Gómez Michelle García‑Arroyo +3 位作者 Camilo ESánchez‑Sarria JRoberto Sosa‑López Diego Santiago‑Alarcon Ian MacGregor‑Fors 《Avian Research》 CSCD 2020年第2期92-105,共14页
Background:Cities differ from non-urban environments by the intensity,scale,and extent of anthropogenic pres-sures,which can drive the occurrence,physiology,and behavior of the organisms thriving in these settings.Tra... Background:Cities differ from non-urban environments by the intensity,scale,and extent of anthropogenic pres-sures,which can drive the occurrence,physiology,and behavior of the organisms thriving in these settings.Traits as green cover often predict the occurrence patterns of bird species in urban areas.Yet,anthropogenic noise and artificial light at night(ALAN)could also limit the presence and disrupt the behavior of birds.However,there is still a dearth of knowledge about the influence of urbanization through noise and light pollution on nocturnal bird species ecology.In this study,we assessed the role of green cover,noise,and light pollution on the occurrence and vocal activity of the Mottled Owl(Ciccaba virgata)in the city of Xalapa(Mexico).Methods:We obtained soundscape recordings in 61 independent sites scattered across the city of Xalapa using autonomous recording units.We performed a semi-automated acoustic analysis of the recordings,corroborating all Mottled Owl vocalizations.We calculated two measures of anthropogenic noise at each study site:daily noise(during 24 h)and masking noise(mean noise amplitude at night per site that could mask the owl’s vocalizations).We further performed generalized linear models to relate green cover,ALAN,daily noise,and masking noise in relation to the owl’s occurrence(i.e.,detected,undetected).We also ran linear models to assess relationships among the beginning and ending of vocal activity with ALAN,and with the anthropogenic and masking noise levels at the moment of which vocalizations were emitted.Finally,we explored variations of the vocal activity of the Mottled Owl measured as vocalization rate across time.Results:The presence of Mottled Owls increased with the size of green cover and decreased with increases in both artificial light at night and noise levels.At the temporal scale,green cover was positively related with the ending of the owl’s vocal activity,while daily noise and ALAN levels were not related to the timing and vocal output(i.e.,number of vocalizations).Furthermore,the Mottled Owl showed a marked peak of vocal activity before dawn than after dusk.Although anthropogenic noise levels varied significantly across the assessed time,we did not find an association between high vocal output during time periods with lower noise levels.Conclusions:Spatially,green cover area was positively related with the presence of the Mottled Owl in Xalapa,while high noise and light pollution were related to its absence.At a temporal scale,daily noise and ALAN levels were not related with the timing and vocal output.This suggests that instead of environmental factors,behavioral contexts such as territoriality and mate interactions could drive the vocal activity of the Mottled Owl.Further studies need to incorporate a wider seasonal scale in order to explore the variation of different vocalizations of this species in relation to environmental and biological factors. 展开更多
关键词 Anthropogenic noise Acoustic monitoring Nighttime ecology Urban ecology URBANIZATION Vocal activity
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Erratum to:Aqueous extracts from Tenebrio molitor larval and pupal stages inhibit early hepatocarcinogenesis in vivo
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作者 Dulce María Moreno-García Armando Zepeda-Bastida +7 位作者 Juan Ocampo-López Brisa Rodope Alarcón-Sánchez Osiris Germán Idelfonso-García Sandra Rosas-Madrigal Diana Ivette Aparicio-Bautista Julio Isael Pérez-Carreón Saúl Villa-Treviño Jaime Arellanes-Robledo 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2023年第4期371-372,共2页
Following an Assessment by the Autonomous University of Hidalgo State and the National Institute of Genomic Medicine,this erratum corrects the authorship of this article by adding Dulce Maria MORENO-GARCiA as the firs... Following an Assessment by the Autonomous University of Hidalgo State and the National Institute of Genomic Medicine,this erratum corrects the authorship of this article by adding Dulce Maria MORENO-GARCiA as the first author.The published article(Zepeda-Bastida et al.,2021)has now been updated with the corrected authorship,author contributions,and acknowledgments,which may be seen in this erratum. 展开更多
关键词 LARVAL adding corrected
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