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1.
Cell ; 137(5): 961-71, 2009 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-19490899

RESUMEN

It has been proposed that two amino acid substitutions in the transcription factor FOXP2 have been positively selected during human evolution due to effects on aspects of speech and language. Here, we introduce these substitutions into the endogenous Foxp2 gene of mice. Although these mice are generally healthy, they have qualitatively different ultrasonic vocalizations, decreased exploratory behavior and decreased dopamine concentrations in the brain suggesting that the humanized Foxp2 allele affects basal ganglia. In the striatum, a part of the basal ganglia affected in humans with a speech deficit due to a nonfunctional FOXP2 allele, we find that medium spiny neurons have increased dendrite lengths and increased synaptic plasticity. Since mice carrying one nonfunctional Foxp2 allele show opposite effects, this suggests that alterations in cortico-basal ganglia circuits might have been important for the evolution of speech and language in humans.


Asunto(s)
Sustitución de Aminoácidos , Ganglios Basales/metabolismo , Evolución Biológica , Factores de Transcripción Forkhead/metabolismo , Vocalización Animal , Animales , Dendritas/metabolismo , Dopamina/metabolismo , Expresión Génica , Heterocigoto , Humanos , Lenguaje , Depresión Sináptica a Largo Plazo , Ratones , Vías Nerviosas , Plasticidad Neuronal , Habla
2.
Environ Monit Assess ; 196(4): 392, 2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38520558

RESUMEN

Climate change is one of the main factors affecting biodiversity worldwide at an alarming rate. In addition to increases in global extreme weather events, melting of polar ice caps, and subsequent sea level rise, climate change might shift the geographic distribution of species. In recent years, interest in understanding the effects of climate change on species distribution has increased, including species which depend greatly on forest cover for survival, such as strictly arboreal primates. Here, we generate a series of species distribution models (SDMs) to evaluate future projections under different climate change scenarios on the distribution of the black howler monkey (Alouatta pigra), an endemic endangered primate species. Using SDMs, we assessed current and future projections of their potential distribution for three Social Economic Paths (SSPs) for the years 2030, 2050, 2070, and 2090. Specifically, we found that precipitation seasonality (BIO15, 30.8%), isothermality (BIO3, 25.4%), and mean diurnal range (BIO2, 19.7.%) are the main factors affecting A. pigra distribution. The future climate change models suggested a decrease in the potential distribution of A. pigra by projected scenarios (from - 1.23 to - 12.66%). The highly suitable area was the most affected above all in the more pessimist scenario most likely related to habitat fragmentation. Our study provides new insights into the potential future distribution and suitable habitats of Alouatta pigra. Such information could be used by local communities, governments, and non-governmental organizations for conservation planning of this primate species.


Asunto(s)
Alouatta , Árboles , Animales , Cambio Climático , Monitoreo del Ambiente , Ecosistema , Especies en Peligro de Extinción
3.
Inorg Chem ; 62(19): 7545-7556, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-37130307

RESUMEN

The control of metal-sugar complexes speciation in solution is crucial in an energy transition context. Herein, the formation of tungstate-mannose complexes is unraveled in aqueous solution using a multitechnique experimental and theoretical approach. 13C nuclear magnetic resonance (NMR), as well as 13C-1H and 1H-1H correlation spectra, analyzed in the light of coordination-induced shift method and conformation analysis, were employed to characterize the structure of the sugar involved in the complexes. X-ray absorption near edge structure spectroscopy was performed to provide relevant information about the metal electronic and coordination environment. The calculation of 13C NMR chemical shifts for a series of tungstate-mannose complexes using density functional theory (DFT) is a key to identify the appropriate structure among several candidates. Furthermore, a parametric study based on several relevant parameters, namely, pH and tungstate concentration, was carried out to look over the change of the nature and concentrations of the complexes. Two series of complexes were detected, in which the metallic core is either in a ditungstate or a monotungstate form. With respect to previous proposals, we identify two new species. Dinuclear complexes involve both α- and ß-furanose forms chelating the metallic center in a tetradentate fashion. A hydrate form chelating a ditungstate core is also revealed. One monotungstate complex appears at high pH, in which a tetrahedral tungstate center is bound to α-mannofuranose through a monodentate site at the second deprotonated hydroxyl group. This unequalled level of knowledge opens the door to structure-reactivity relationships.

4.
Biol Sport ; 40(3): 813-825, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37398956

RESUMEN

Quercetin (Q) is one of the most frequently consumed flavonoids in the human diet. The purpose of this systematic review and meta-analysis was to determine the effects of Q supplementation on muscle damage, muscle soreness and biochemical markers of inflammation, antioxidant capacity and oxidative stress after intense exercise. A literature search of SPORTDiscus, PubMed, Web of Science and Scopus was performed from inception to May 31, 2022. Forest plots were generated with fixed or random-effect models and standardized mean differences (SMD). Data extraction and quality assessment were performed independently by two authors. After application of the inclusion and exclusion criteria, 13 studies with a total of 249 sedentary to well-trained participants were included. For all studies there were some concerns about the risk of bias. All but one study used a supplementation dosage of 1000 mg/day. Q supplementation accelerated recovery of muscle function and significantly decreased muscle soreness 0/24 h after exercise (SMD: -1.33; p = 0.03), creatine kinase levels 24/48 h after exercise (SMD: -1.15; p = 0.02), and post-exercise oxidative stress (SMD: -0.92; p = 0.03). However, Q supplementation had no effect on IL-6 concentration. Q supplementation with a dose of 1000 mg/day for periods of more than seven days and a maximum of 12 weeks appears to be a safe and efficacious strategy to reduce muscle damage and muscle soreness, as well as to enhance recovery after intense exercise in sedentary to well-trained young men. Systematic review registration: PROSPERO CRD42021266801.

5.
Indoor Air ; 32(5): e13040, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35622718

RESUMEN

Post-epidemic protocols have been implemented in public buildings to keep indoor environments safe. However, indoor environmental conditions are affected by this decision, which also affect the occupants of buildings. This fact has major implications in educational buildings, where the satisfaction and learning performance of students may also be affected. This study investigates the impact of post-epidemic protocols on indoor environmental conditions in higher education buildings of one Portuguese and one Spanish university. A sensor monitoring campaign combined with a simultaneous questionnaire was conducted during the reopening of the educational buildings. Results showed that although renewal air protocols were effective and the mean CO2 concentration levels remained low (742 ppm and 519 ppm in Portugal and Spain universities, respectively), students were dissatisfied with the current indoor environmental conditions. Significant differences were also found between the responses of Portuguese and Spanish students. Indeed, Spanish students showed warmer preferences (thermal neutrality = 23.3℃) than Portuguese students (thermal neutrality = 20.7℃). In terms of involved indoor factors, the obtained data showed significant correlations (p < 0.001) between acoustic factors and overall satisfaction in the Portuguese students (ρ = 0.540) and between thermal factors and overall satisfaction in the Spanish students (ρ = 0.522). Therefore, indoor environmental conditions should be improved by keeping spaces safe while minimizing the impact of post-epidemic protocols on student learning performance.


Asunto(s)
Contaminación del Aire Interior , COVID-19 , Contaminación del Aire Interior/análisis , Humanos , Portugal , Respiración , España , Temperatura
6.
J Acoust Soc Am ; 152(3): 1515, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36182289

RESUMEN

Technical and technological advances have revolutionised the architecture, engineering, and construction industries in recent decades. Building information modelling (BIM) methodology has become essential in the process of information management and the development of building projects. This study aims to analyse the potential advantages of the implementation of BIM-based models for the acquisition of theoretical and procedural knowledge about building acoustics. This procedure was implemented as part of a problem-solving exercise in Science, Technology, Engineering, and Mathematics (STEM) university degrees. For this purpose, three-dimensional (3D) BIM models were generated to assess the contribution of their implementation in the process of visualization, comprehension, and analysis of the acoustic behaviour of buildings. The participants' experiences and satisfaction with the BIM models were measured through a questionnaire. The results showed a high level of satisfaction among the participants and good potential for the application of 3D models based on BIM methodology for the acquisition of knowledge and practical skills in building acoustics. These results highlight the potential of BIM models to provide information for understanding the procedure followed during data collection in the experimental analysis and to facilitate the understanding of system behavior.


Asunto(s)
Comprensión , Industria de la Construcción , Acústica , Industria de la Construcción/métodos , Ingeniería , Humanos
7.
Ecol Lett ; 24(12): 2635-2647, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34536250

RESUMEN

Canopy disturbance explains liana abundance and distribution within tropical forests and thus may also explain the widespread pattern of increasing liana abundance; however, this hypothesis remains untested. We used a 10-year study (2007-2017) of 117,100 rooted lianas in an old-growth Panamanian forest to test whether local canopy disturbance explains increasing liana abundance. We found that liana density increased 29.2% and basal area 12.5%. The vast majority of these increases were associated with clonal stem proliferation following canopy disturbance, particularly in liana-dense, low-canopy gaps, which had far greater liana increases than did undisturbed forest. Lianas may be ecological niche constructors, arresting tree regeneration in gaps and thus creating a high-light environment that favours sustained liana proliferation. Our findings demonstrate that liana abundance is increasing rapidly and their ability to proliferate via copious clonal stem production in canopy gaps explains much of their increase in this and possibly other tropical forests.


Asunto(s)
Bosques , Clima Tropical , Ecosistema , Árboles
8.
Am J Ind Med ; 64(4): 258-265, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33543496

RESUMEN

BACKGROUND: As global temperatures rise, increasing numbers of individuals will work in hot environments. Interventions to protect their health are critical, as are reliable methods to measure the physiological strain experienced from heat exposure. The physiological strain index (PSI) is a measure of heat strain that relies on heart rate and core temperature but is challenging to calculate in a real-world occupational setting. METHODS: We modified the PSI for use in field settings where resting temperature and heart rate are not available and used the modified physiological strain index (mPSI) to describe risk factors for high heat strain (mPSI ≥ 7) experienced by agricultural workers in Florida during the summers of 2015 through 2017. mPSI was calculated for 221 workers, yielding 465 days of data. RESULTS: A higher heat index (ß = 0.185; 95% CI: 0.064, 0.307) and higher levels of physical activity at work (0.033; 95% CI: 0.017, 0.050) were associated with a higher maximum mPSI. More years worked in US agriculture (-0.041; 95% CI: -0.061, -0.020) were protective against a higher maximum mPSI. Out of 23 workdays that a participant experienced a maximum mPSI ≥ 7, 22 were also classified as strained by at least one other measure of high heat strain (core temperature [Tc] >38.5°C, sustained heart rate >(180 - age), and mean heart rate > 115 bpm). CONCLUSIONS: This study provides critical information on risk factors for elevated heat strain for agricultural workers and suggests a practical approach for using PSI in field-based settings.


Asunto(s)
Agricultura , Temperatura Corporal/fisiología , Exposición Profesional/efectos adversos , Esfuerzo Físico/fisiología , Trabajo/fisiología , Actigrafía , Adolescente , Adulto , Ejercicio Físico , Agricultores/estadística & datos numéricos , Femenino , Florida/epidemiología , Frecuencia Cardíaca/fisiología , Trastornos de Estrés por Calor/epidemiología , Trastornos de Estrés por Calor/etiología , Calor/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Profesionales/epidemiología , Enfermedades Profesionales/etiología , Exposición Profesional/análisis , Factores de Riesgo , Lugar de Trabajo , Adulto Joven
9.
Sensors (Basel) ; 21(21)2021 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-34770530

RESUMEN

Since students and teachers spend much of their time in educational buildings, it is critical to provide good levels of indoor environmental quality (IEQ). The current COVID-19 pandemic has shown that maintaining a good indoor air quality level is an effective measure to control the transmission of the SARS-CoV-2 virus. This study used sensors to monitor key IEQ factors and assess several natural ventilation scenarios in a classroom of the University of Granada. Subsequently, the IEQ factors (temperature, relative humidity, CO2 concentration, acoustic environment, and air velocity) were evaluated for the selected ventilation scenarios in the occupied classroom, and the field monitoring was carried out in two different assessment periods, winter and summer. The obtained results show that the CO2 concentration levels were well below the recommended limits. However, the maintenance of the recommended thermal and acoustic IEQ factors was significantly affected by the natural ventilation strategies (temperature and relative humidity values were very close to the outside values, and the background sound pressure level was over 35 dBA during the entire assessment). The proper measurements and careful selection of the appropriate ventilation scenarios become of utmost importance to ensure that the ventilation rates required by the health authorities are achieved.


Asunto(s)
Contaminación del Aire Interior , COVID-19 , Contaminación del Aire Interior/análisis , Monitoreo del Ambiente , Humanos , Pandemias , SARS-CoV-2 , España , Temperatura , Ventilación
10.
Sensors (Basel) ; 21(18)2021 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-34577328

RESUMEN

Indoor environmental conditions can significantly affect occupants' health and comfort. These conditions are especially important in educational buildings, where students, teachers and staff spend long periods of the day and are vulnerable to these factors. Recently, indoor air quality has been a focus of attention to ensure that disease transmission in these spaces is minimised. In order to increase the knowledge in this field, experimental tests have been carried out to characterise the impact of natural ventilation strategies on indoor air quality and the acoustic environment. This study has evaluated three ventilation scenarios in four different classrooms in buildings of the University of Granada, considering different window and door opening configurations. Ventilation rates were estimated using the CO2 Decay Method, and background noise recordings were made in each classroom for acoustic tests. Results show that specific natural ventilation strategies have a relevant impact that is worth considering on the background noise in indoor spaces. In this sense ventilation rates provided by the different configurations varied between 3.7 and 39.8 air changes per hour (ACH) and the acoustic tests show a background noise ranging from 43 to 54 dBA in these scenarios. Consequently, managers and teachers should take into account not only the ACH, but also other collateral impacts on the indoor environmental conditions such as the thermal comfort or the acoustic environment.


Asunto(s)
Contaminación del Aire Interior , Ventilación , Acústica , Contaminación del Aire Interior/análisis , Humanos , Ruido , Estudiantes
11.
Rev Med Suisse ; 17(757): 1890-1893, 2021 Nov 03.
Artículo en Francés | MEDLINE | ID: mdl-34738764

RESUMEN

The increasing life expectancy, the earlier detection of terminal illnesses and the increasing complexity of care pathways led us to propose an innovative response within the Neuchâtel Hospital Network (RHNe), in the form of a mixed intra-hospital mobile team (GSPmob), composed of doctors and nurses from geriatrics and palliative care. Through geriatric and palliative assessment, we are able to highlight the patient's different medical problems. Our team, after two years of existence, has met our patients' needs as well as the hospital teams' needs. And yet we encountered certain challenges. Our current objective is to describe our experience by presenting our results and difficulties.


L'augmentation de l'espérance de vie, la détection plus précoce de maladies terminales et la complexification des parcours de soins nous ont amenés à proposer une réponse innovante au sein du Réseau hospitalier neuchâtelois, sous forme d'une équipe mobile mixte intrahospitalière, de médecins et infirmiers issus de la gériatrie ou des soins palliatifs (équipe mobile mixte de gériatrie et de soins palliatifs). Grâce aux évaluations gériatriques et palliatives, cette équipe permet la détection et la prise en charge de différentes problématiques spécifiques chez les patients. Depuis près de 2 ans d'existence, malgré les défis qui restent à relever, notre équipe répond à un réel besoin des patients et des équipes soignantes. L'objectif est ici de décrire notre expérience en présentant nos résultats et nos difficultés.


Asunto(s)
Geriatría , Cuidados Paliativos , Anciano , Hospitales , Humanos , Esperanza de Vida , Grupo de Atención al Paciente
12.
J Med Primatol ; 48(2): 99-105, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30520095

RESUMEN

BACKGROUND: Bifidobacterium genus are considered to be beneficial bacteria for their hosts; however, knowledge about the specific species that are part of the gut microbiome of howler monkeys is scarce. Polymerase chain reaction (PCR) is a useful technique for the identification of non-cultivable or difficult to grow bacterial species. With the goal of detecting species of the genus Bifidobacterium in black howler monkeys, we used PCR on DNA derived from faecal samples. METHODS: We collected and extracted DNA from 40 faecal samples. Using specific primers, we performed PCR and nested PCR to detect members of the Bifidobacterium genus and a subset of species: Bifidobacterium adolescentis, Bifidobacterium bifidum, Bifidobacterium infantis, Bifidobacterium longum and Bifidobacterium animalis subsp. animalis. RESULTS: 97.5% (39/40) of the samples were positive for Bifidobacterium spp. We found B longum in 100% of the analysed samples. CONCLUSIONS: This is the first report of B longum in black howler monkey faeces.


Asunto(s)
Alouatta/microbiología , Bifidobacterium/aislamiento & purificación , Animales , Heces/microbiología , Femenino , Masculino , México , Reacción en Cadena de la Polimerasa/veterinaria
13.
J Hered ; 110(2): 229-246, 2019 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-30496534

RESUMEN

The host dependence of mistletoes suggests that they track the distributions of their hosts. However, the factors that determine the geographic distribution of mistletoes are not well understood. In this study, the phylogeography of Psittacanthus sonorae was reconstructed by sequencing one nuclear (ITS) and two plastid (trnL-F and atpB-rbcL) regions of 148 plants from populations separated by the Sea of Cortez. Divergence time and gene flow were estimated to gain insight into the historical demography and geographic structuring of genetic variation. We also described and mapped the spatial distribution of suitable habitat occupied by P. sonorae and its most common host Bursera microphylla in the Sonoran Desert, along with their responses to Quaternary climate fluctuations using environmental data and ecological niche modeling (ENM). We detected environmental and genetic differentiation between the peninsular and continental P. sonorae populations. Population divergence occurred during the Pleistocene, around the time of the Last Glacial Maximum. No signals of population growth were detected, with net gene flow moving from the continent to the peninsula. ENM models indicate decoupled responses by the mistletoe and its main host to past climate changes. For the Last Interglacial to the present, most models produce only partial areas of overlap on both the peninsula and the continent. Our results support a scenario of Late-Pleistocene isolation and divergence with asymmetrical gene flow between peninsular and continental P. sonorae populations. Continental populations migrated to the peninsula and the spatial isolation probably produced genetic differentiation under different environmental conditions.


Asunto(s)
Loranthaceae/clasificación , Loranthaceae/genética , Filogenia , Filogeografía , Evolución Biológica , Clima Desértico , Ambiente , Variación Genética , Genética de Población , Geografía , Haplotipos , Modelos Teóricos
14.
Am J Ind Med ; 62(12): 1058-1067, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31418883

RESUMEN

BACKGROUND: Laboring in hot and humid conditions is a risk factor for heat-related illnesses. Little is known about the amount of physical activity performed in the field setting by agricultural workers, a population that is among those at highest risk for heat-related mortality in the United States. METHODS: We measured accelerometer-based physical activity and work activities performed in 244 Florida agricultural workers, 18 to 54 years of age, employed in the fernery, nursery, and crop operations during the summer work seasons of 2015-2017. Environmental temperature data during the participant's workdays were collected from the Florida Automated Weather Network and used to calculate wet bulb globe temperature (WBGT). Generalized linear mixed model regression was used to examine the association between WBGT on physical activity, stratified by the agricultural sector. RESULTS: Fernery workers had the highest overall volume of physical activity, spending nearly 4 hours in moderate to vigorous activity per workday. Activity over the course of the workday also differed by the agricultural sector. A reduction on average physical activity with increasing environmental temperature was observed only among crop workers. CONCLUSIONS: The quantity and patterns of physical activity varied by the agricultural sector, sex, and age, indicating that interventions that aim to reduce heat-related morbidity and mortality should be tailored to specific subpopulations. Some workers did not reduce overall physical activity under dangerously hot environmental conditions, which has implications for policies protecting worker health. Future research is needed to determine how physical activity and climatic conditions impact the development of heat-related disorders in this population.


Asunto(s)
Ejercicio Físico/fisiología , Agricultores/estadística & datos numéricos , Exposición Profesional/análisis , Carga de Trabajo/estadística & datos numéricos , Acelerometría , Adulto , Agricultura/métodos , Femenino , Florida , Humanos , Masculino , Persona de Mediana Edad , Trabajo , Adulto Joven
15.
J Nurs Scholarsh ; 50(1): 74-82, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29024370

RESUMEN

BACKGROUND: Farmworkers working in hot and humid environments have an increased risk for heat-related illness (HRI) if their thermoregulatory capabilities are overwhelmed. The manifestation of heat-related symptoms can escalate into life-threatening events. Increasing ambient air temperatures resulting from climate change will only exacerbate HRI in vulnerable populations. We characterize HRI symptoms experienced by farmworkers in three Florida communities. METHODS: A total of 198 farmworkers enrolled in 2015-2016 were asked to recall if they experienced seven HRI symptoms during the previous work week. Multivariable logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the association between selected sociodemographic characteristics and reporting three or more symptoms. Latent class analysis was used to identify classes of symptoms representing the HRI severity range. We examined sociodemographic characteristics of the farmworkers across the latent classes. RESULTS: The mean age (±SD) of farmworkers was 38.0 (±8) years; the majority were female (60%) and Hispanic (86%). Most frequently reported symptoms were heavy sweating (66%), headache (58%), dizziness (32%), and muscle cramps (30%). Females had three times the odds of experiencing three or more symptoms (OR = 2.86, 95% CI 1.18-6.89). Symptoms fell into three latent classes, which included mild (heavy sweating; class probability = 54%), moderate (heavy sweating, headache, nausea, and dizziness; class probability = 24%), and severe (heavy sweating, headache, nausea, dizziness, muscle cramps; class probability = 22%). CONCLUSIONS: Farmworkers reported a high burden of HRI symptoms that appear to cluster in physiologic patterns. Unrecognized accumulation of symptoms can escalate into life-threatening situations if untreated. Our research can inform interventions to promote early recognition of HRI, on-site care, and appropriate occupational health policy. Administrative or engineering workplace controls may also reduce the manifestation of HRI. CLINICAL RELEVANCE: This study advances the current knowledge of HRI symptoms in farmworkers and moves beyond reporting individual symptoms by utilizing latent class analysis to identify how symptoms tend to co-occur together in this population. It acknowledges multiple symptoms occurring as a result of occupational heat exposure and highlights the importance of symptom recognition.


Asunto(s)
Enfermedades de los Trabajadores Agrícolas/clasificación , Agricultores , Trastornos de Estrés por Calor/clasificación , Calor/efectos adversos , Adulto , Enfermedades de los Trabajadores Agrícolas/epidemiología , Agricultores/estadística & datos numéricos , Femenino , Florida/epidemiología , Trastornos de Estrés por Calor/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
16.
Phys Chem Chem Phys ; 19(25): 16765-16774, 2017 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-28627564

RESUMEN

The present paper focuses on the characterization of the properties of methanol and water molecules in gas and liquid environments. A force field for methanol-methanol and methanol-water interactions, useful to be applied in Molecular Dynamics (MD) simulations, is proposed. The electrostatic interaction contributions, arising from permanent charge and/or from anisotropic charge distributions originating from permanent electric multipoles (Vel), different in gas and in liquid phases, are combined with the non electrostatic ones (Vnel), defined by means of Improved Lennard-Jones (ILJ) functions [F. Pirani et al., Phys. Chem. Chem. Phys., 2008, 10, 5489-5503]. Interestingly, the relevant parameters of the ILJ functions are not fitted to reproduce the selected properties of the systems but calculated from the molecular polarizability, which is considered the key property to define size (or Pauli) repulsion and dispersion and induction attractions. The constructed force field predicts binding energies and geometries of the methanol-methanol and methanol-water dimers, in good agreement with available data. On the other hand, several bulk and structural properties of liquid methanol, such as densities, vaporization enthalpies, diffusion coefficients, coefficients of cubic thermal expansion, heat capacities at constant pressure and some relevant radial distribution functions, calculated considering 2744 molecules and different conditions of pressure and temperature, have also been found to be in good agreement with experimental data. The study has been completed by calculating the density values at 298 K and 1 bar of some methanol-water mixtures, which have also been found to be in good agreement with experimental data.

17.
BMC Evol Biol ; 16: 78, 2016 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-27071983

RESUMEN

BACKGROUND: Ecological adaptation to host taxa is thought to result in mistletoe speciation via race formation. However, historical and ecological factors could also contribute to explain genetic structuring particularly when mistletoe host races are distributed allopatrically. Using sequence data from nuclear (ITS) and chloroplast (trnL-F) DNA, we investigate the genetic differentiation of 31 Psittacanthus schiedeanus (Loranthaceae) populations across the Mesoamerican species range. We conducted phylogenetic, population and spatial genetic analyses on 274 individuals of P. schiedeanus to gain insight of the evolutionary history of these populations. Species distribution modeling, isolation with migration and Bayesian inference methods were used to infer the evolutionary transition of mistletoe invasion, in which evolutionary scenarios were compared through posterior probabilities. RESULTS: Our analyses revealed shallow levels of population structure with three genetic groups present across the sample area. Nine haplotypes were identified after sequencing the trnL-F intergenic spacer. These haplotypes showed phylogeographic structure, with three groups with restricted gene flow corresponding to the distribution of individuals/populations separated by habitat (cloud forest localities from San Luis Potosí to northwestern Oaxaca and Chiapas, localities with xeric vegetation in central Oaxaca, and localities with tropical deciduous forests in Chiapas), with post-glacial population expansions and potentially corresponding to post-glacial invasion types. Similarly, 44 ITS ribotypes suggest phylogeographic structure, despite the fact that most frequent ribotypes are widespread indicating effective nuclear gene flow via pollen. Gene flow estimates, a significant genetic signal of demographic expansion, and range shifts under past climatic conditions predicted by species distribution modeling suggest post-glacial invasion of P. schiedeanus mistletoes to cloud forests. However, Approximate Bayesian Computation (ABC) analyses strongly supported a scenario of simultaneous divergence among the three groups isolated recently. CONCLUSIONS: Our results provide support for the predominant role of isolation and environmental factors in driving genetic differentiation of Mesoamerican parrot-flower mistletoes. The ABC results are consistent with a scenario of post-glacial mistletoe invasion, independent of host identity, and that habitat types recently isolated P. schiedeanus populations, accumulating slight phenotypic differences among genetic groups due to recent migration across habitats. Under this scenario, climatic fluctuations throughout the Pleistocene would have altered the distribution of suitable habitat for mistletoes throughout Mesoamerica leading to variation in population continuity and isolation. Our findings add to an understanding of the role of recent isolation and colonization in shaping cloud forest communities in the region.


Asunto(s)
Bosques , Loranthaceae/genética , Teorema de Bayes , Evolución Biológica , Cambio Climático , Ecosistema , Flujo Génico , Variación Genética , Haplotipos , Humanos , Loranthaceae/clasificación , Modelos Biológicos , Filogenia , Filogeografía
18.
Gac Med Mex ; 151(3): 323-8, 2015.
Artículo en Español | MEDLINE | ID: mdl-26089268

RESUMEN

OBJECTIVE: To describe the early complications of esophageal replacement with colon in children. METHODS: Descriptive cross-sectional study from 2005 to 2011 in pediatric patients diagnosed with alkali intake, esophageal atresia or esophageal injury traumatic esophageal replacement handled via retrosternal colon. Descriptive statistical analysis using SPSS 20.0. RESULTS: We included 19 esophageal replacements, age seven (4-15), 13 (68%) male and six (31%) female. Initial diagnosis of ingestion of caustic 13 patients (68%) and type III esophageal atresia six cases (32%). Of the six esophageal atresia, four(66%) had dehiscence plasty, one (17%) long-gap atresia and type 1 (17%) esophageal perforation by dilatation. The segment of transverse colon was used in eight (42%), transverse/descending seven (36%), ascending/transverse three (15%), and descending colon one (5%). Early complications were pneumothorax one patient (5%), pneumonia three (15%), sepsis three (15%), intestinal obstruction due to adhesions two (10%), intussusception one (5%), cervical fistula three (15%). One death from sepsis (5%) at four days after surgery. DISCUSSION: Esophageal replacement with colon is a good alternative for esophageal replacement; the most frequent early complications were cervical fistula, pneumonia, and sepsis.


Asunto(s)
Colon/trasplante , Atresia Esofágica/cirugía , Enfermedades del Esófago/cirugía , Complicaciones Posoperatorias/epidemiología , Estudios Transversales , Enfermedades del Esófago/patología , Esófago/lesiones , Esófago/patología , Esófago/cirugía , Femenino , Humanos , Lactante , Masculino , Complicaciones Posoperatorias/fisiopatología
19.
Spine Deform ; 12(4): 1115-1126, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38589595

RESUMEN

INTRODUCTION: Poor restoration of pelvic version after adult spinal deformity (ASD) surgery is associated with an increased risk of mechanical complications and worse quality of life. We studied the factors linked to the improvement of postoperative pelvic version. MATERIALS AND METHODS: This is a retrospective analysis of a prospective multicenter ASD database. Selection criteria were: operated patients having preoperative severe pelvic retroversion as per GAP score (Relative Pelvic Version-RPV < - 15°); panlumbar fusions to the pelvis; 2-year follow-up. Group A comprised patients with any postoperative improvement of RPV score, and group B had no improvement. Groups were compared regarding baseline characteristics, surgical factors, and postoperative sagittal parameters. Parametric and non-parametric analyses were employed. RESULTS: 177 patients were studied, median age 67 years (61; 72.5), 83.6% female. Groups were homogeneous in baseline demographics, comorbidities, and preoperative sagittal parameters (p > 0.05). The difference in RPV improvement was 11.56º. Group A (137 patients) underwent a higher percentage of ALIF procedures (OR = 6.66; p = 0.049), and posterior osteotomies (OR = 4.96; p < 0.001) especially tricolumnar (OR = 2.31; p = 0.041). It also showed a lower percentage of TLIF procedures (OR = 0.45; p = 0.028), and posterior decompression (OR = 0.44; p = 0.024). Group A displayed better postoperative L4-S1 angle and relative lumbar lordosis (RLL), leading to improved sacral slope (and RPV), and global alignment (RSA). Group A patients had longer instrumentations (11.45 vs 10; p = 0.047) and hospitalization time (13 vs 11; p = 0.045). All postoperative sagittal parameters remained significantly better in group A through follow-up. However, differences between the groups narrowed over time. CONCLUSIONS: ALIF procedures and posterior column osteotomies improved pelvic version postoperatively, and associated better L4-S1 and lumbar lordosis restoration, indirectly improving all other sagittal parameters. However, these improvements seemed to fade during the 2-year follow-up.


Asunto(s)
Fusión Vertebral , Humanos , Femenino , Masculino , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Fusión Vertebral/métodos , Fusión Vertebral/efectos adversos , Resultado del Tratamiento , Pelvis/cirugía , Osteotomía/métodos , Calidad de Vida , Curvaturas de la Columna Vertebral/cirugía , Lordosis/cirugía
20.
Nutr Res ; 123: 80-87, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38281320

RESUMEN

Fat mass percentage (%FM) is frequently determined by nutritionists and personal trainers with bioelectrical impedance analysis (BIA) devices. The aims of the present study were: (1) to develop new regression equations using dual-energy X-ray absorptiometry (DXA) as the reference method for estimating %FM in a heterogeneous Caucasian population with a foot-to-hand device (BIA-101) and a hand-to-hand device (BIA-TELELAB) and (2) to compare the new equations with the manufacturers' equations. We hypothesized that the new equations would lead to more accurate estimations compared with DXA. A total of 218 healthy Caucasian participants aged 18 to 65 years were divided into a development group and a validation group. The accuracy of the different equations was assessed by mean differences, coefficient of determination, standard error of the estimate (SEE), intraclass correlation coefficients (ICC), and Bland-Altman plots. The proposed equation for BIA-101 explained 90.0% of the variance in the DXA-derived %FM, with a low random error (SEE = 2.98%), excellent agreement (ICC = 0.94), no fixed bias, and relatively low individual variability (5.86%). For BIA-TELELAB, the proposed equation explained 88.0% of the variance in the DXA-derived %FM, with a low random error (SEE = 3.27%), excellent agreement (ICC = 0.93), no fixed bias, and relatively low individual variability (6.37%). The results obtained for the manufacturers' equations confirm that these equations are not a good option for %FM assessment. As hypothesized, the new regression equations for BIA-101 and BIA-TELELAB devices can accurately estimate %FM in a heterogeneous Caucasian population with a broad age range.


Asunto(s)
Composición Corporal , Impedancia Eléctrica , Humanos , Absorciometría de Fotón/métodos , Índice de Masa Corporal , Reproducibilidad de los Resultados , Población Blanca , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano
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