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To assess whether performance in attention and executive functions evaluated with the Epitrack screening tool before surgery can differentiate memory and quality of life (QOL) profiles, and detect different post-surgical change patterns in these variables in patients with epilepsy. This is a longitudinal study. Seventy-seven patients with drug-resistant epilepsy (mean age = 37.91) underwent a neuropsychological assessment before and one year after surgery. Epitrack, a screening tool that exclusively evaluates attention and executive functioning, was administered in the pre-surgical assessment, and verbal and visual memory and QOL were assessed before and after surgery. Patients with impaired Epitrack performance had poorer verbal and visual memory than those with intact Epitrack performance, regardless of the time point (for all, p < 0.0001). They also showed a post-surgical decline in immediate verbal recall (p = 0.04) and discriminability (p = 0.001). Patients with intact Epitrack performance did not exhibit this decline. Epitrack total score significantly contributed to 13 and 11% of the variance of post-surgical changes in immediate verbal recall and discriminability, respectively. Epitrack groups did not differ in QOL profiles or changes, but post-surgical immediate verbal recall improvements were related to post-surgical QOL improvements. Our findings underline the utility of Epitrack screening tool to detect different patterns of verbal and visual memory dysfunction, as well as to predict post-surgical verbal memory decline in patients with drug-resistant epilepsy. Patients with lower pre-surgical Epitrack scores appear to be at increased risk for post-surgical memory decline. [ABSTRACT FROM AUTHOR]

Objective The aim was to examine the effect of polytherapy (i.e. the number of administered anti-seizure medications (ASMs)) on memory, and whether the interaction between the number of ASMs and attentional/executive functioning affect presurgical memory functioning and postsurgical memory changes in patients with drug-resistant epilepsy. Methods Two studies were carried out. Study 1 consisted of a presurgical assessment of 125 adult patients, in which attention/executive function (EpiTrack screening tool) and memory were assessed (cross-sectional study). Of them, 72 patients underwent a second postsurgical evaluation, in which memory was assessed (Study 2). Patients were distributed into groups based on EpiTrack performance and number of ASMs. Results The interaction between the number of ASMs and the attentional/executive functioning significantly affected presurgical memory, with patients with impaired EpiTrack performance taking three-four ASMs having poorer scores than patients with intact EpiTrack performance taking three-four ASMs (for all, p  < .0001). This interaction also affected postsurgical memory changes, with patients with impaired Epitrack performance taking three-four ASMs having higher postsurgical decline than those with intact Epitrack performance taking three-four ASMs (for all, p  < .005). No differences were found in patients taking two ASMs. Furthermore, the number of ASMs was associated with presurgical memory performance and postsurgical memory changes only in patients with impaired EpiTrack performance (for all, p  < .05). Conclusions Our findings underline the utility of EpiTrack, together with the clinical information on the number of prescribed ASMs, to corroborate the impact of polytherapy on memory and to optimize the prediction of postsurgical memory changes. [ABSTRACT FROM AUTHOR]

This review aims to establish criteria for identifying an adoption process in an archaeological context. We define adoption as raising an individual who does not belong genetically to the family. Adoption appears in different moments of past societies, and when establishing a "family" nucleus burial place we must consider certain social behaviors, such as burials under the houses, collective burials, or laying bodies in specific positions. After observing these signs, we are carrying out a genetic analysis, in order to confirm a biologically related family nucleus. These traces have been traditionally linked to family nuclei because they have been found previously in burials where biological kinship was confirmed. However, there can be cases where, after carrying out the genetic analyses, it is confirmed that certain individuals are not genetically related. In such cases, an adoption case cannot be ruled out. These cases are not easy to identify due to the differences between societies and cultures, so more in-depth studies should be carried out on the type of funeral practice in which these human remains are found to be able to discriminate an adopted individual from one who was not adopted. Therefore, the study of adoption should be carried out based on an in-depth knowledge of the cultural background, before using a powerful tool such as ancient DNA technology. [ABSTRACT FROM AUTHOR]

Purpose: Memory deficits are very frequent in patients with drug-resistant epilepsy, but they predict a small proportion of variance of their quality of life (QOL) in previous studies, possibly due to the lack of consideration of mediating factors of this relationship. This study aimed to examine whether trait anxiety mediates the relationship between memory and QOL in this population, controlling the influence of demographic and seizure-related factors. Methods: In this cross-sectional study, 119 adults with drug-resistant temporal lobe epilepsy (TLE) underwent a neuropsychological evaluation, in which memory, anxiety, and QOL were assessed. Results: In the total sample, better delayed memory had an effect on better QOL indirectly through lower trait anxiety (B = 0.13, SE = 0.06, p = 0.04, abcs = 0.13; κ2 = 0.18; PMind = 0.76). Additionally, delayed memory has not a direct association with QOL (B = 0.04, SE = 0.09, p = 0.64, Cohen's f 2 = 0.005; PMdir = 0.24), and the total effect of delayed memory on QOL tended to reach statistical significance (B = 0.17, SE = 0.10, p = 0.08). The proposed mediation model yielded excellent fit (CFI = 1.00, RMSEA = 0.0001, SRMR = 0.009, and χ2 (1) = 0.50, p = 0.48) and explained 38% of the variance of QOL. Conclusion: These findings suggest that trait anxiety is an important factor in understanding the relationship between memory and QOL in patients with TLE, considering the influence of demographic and seizure-related variables, and may have relevant implications for decision-making in this population. [ABSTRACT FROM AUTHOR]

The Alberca de Tacámbaro (AT) is located at a transitional zone between tropical and temperate climates at the core of the North American Monsoon area. This location features a mosaic vegetation comprising pine-oak forests and tropical dry forests. Currently there is no information regarding the dynamics or evolution during the Holocene of these vegetation types. The palynological record of the last 9400 years BP preserved in the lacustrine sequence of the AT was used to document changes in the composition of terrestrial and aquatic communities, evenness, and rate of change. Pinus and Quercus forests dominated the terrestrial palynological record, but mesophytic forests were also recorded throughout the sequence. Four tropical dry forest taxa assemblage expansions were identified at 9200 to 8420 yr BP; 5900 to 5230 yr BP; 3100 to 2800 yr BP; and 2300 to 2000 yr BP. These phases correlated with times of reduced North American Monsoon intensity, suggesting that these communities thrived during drought periods. Variations in non-pollen palynomorphs were synchronic with the lithostratigraphic, geochemical data as well as with the terrestrial changes. During the Meghalayan, compositional shifts in the vegetation and increases in the herbaceous elements indicated human impact, while aquatic taxa, suggested eutrophic and warmer conditions in the lake. By examining the history of this vegetation mosaic, the data on temporal vegetation dynamics during the Holocene offered clues about the response to ongoing global warming and how climate change will likely shape plant communities in western-central Mexico. • The palynological record documents changes in the composition of terrestrial and aquatic communities during the Holocene. • Four phases of Tropical Dry Forest expansion correlated with periods of reduced monsoon intensity. • Compositional shifts in the terrestrial community were recorded during the Meghalayan age, likely due to human impact in the area. • The proxy data revealed synchronicity in terrestrial and lacustrine ecosystem changes during the Holocene. [ABSTRACT FROM AUTHOR]

[Display omitted] • A higher number of ASMs is related to poorer QOL in 93.3% of studies. • Patients on polytherapy experience worse QOL compared to those on monotherapy. • Higher seizure frequency and mood comorbidities are predictors of poor QOL. • Side and adverse effects of ASMs and social determinants significantly impact QOL. Drug-resistant epilepsy usually requires the use of polytherapy with antiseizure medications (ASMs) for management, which could involve side and adverse effects that may impact quality of life (QOL). This systematic review summarizes the evidence about the relationship between ASM polytherapy and QOL in epilepsy patients, considering clinical, sociodemographic, and psychological variables. This review followed the PRISMA guidelines and was registered in PROSPERO. The studies examined were collected from PubMed/MEDLINE, Scopus, Web of Science, and Embase. The data extracted were categorized into three categories: the relationship between the number of ASMs and QOL, differences in QOL between patients taking polytherapy and patients taking monotherapy, and the role of other variables on QOL. The review included 34 studies. Thirty examined the relationship between the number of ASMs and QOL, 93.3% of them identifying a significant association between a higher number of ASMs and poorer QOL. Fifteen studies analyzed differences in QOL between patients receiving polytherapy and those on monotherapy, all of them showing poorer QOL in those on polytherapy. Thirty-two studies considered other factors beyond polytherapy as determinants of QOL, including clinical, sociodemographic, and psychological variables, and higher seizure frequency and mood comorbidities (depression and anxiety) emerged as the strongest predictors of poor QOL. Polytherapy, despite being necessary for managing drug-resistant epilepsy, significantly contributes to impairing QOL. Effective seizure control remains critical, but a multifactorial approach addressing mental health and social determinants is essential for improving QOL in epilepsy patients. Future research should focus on optimizing treatment strategies that balance seizure control by minimizing the negative impact of polytherapy. [ABSTRACT FROM AUTHOR]

Background: Anti‐seizure medications (ASMs) have been related to poor cognitive function, but their relationship with intracarotid amobarbital procedure (IAP) results remains unclear. Aims of the Study: To elucidate whether the number and drug load of ASMs are associated with memory scores of the IAP and the neuropsychological assessment. Methods: Fifty‐nine adult patients with drug‐resistant epilepsy (mean age = 36.1, SD = 11.6) underwent bilateral IAP (with drawings and words as memory items) and a neuropsychological assessment to assess the risk of post‐surgical memory decline. Total ASM drug load was calculated by summing the daily dose/defined daily dose ratio of every ASM of each patient. Pearson's correlations and hierarchical regressions were computed. Results: Total IAP memory score was associated with total ASM drug load (r = −0.30, p = 0.02) and seizure frequency (r = −0.25, p = 0.05). After controlling clinical variables, total ASM drug load explained 16% of the variance of total IAP memory score. This relationship was especially prominent in patients with left hemisphere focus (r = −0.33, p = 0.04). The number of current ASMs was not related to IAP memory score (r = −0.16, p = 0.24). The number or drug load of ASMs were not related to neuropsychological assessment results (for all, p > 0.07). Conclusions: Our findings suggest that total drug load can be a confounding variable in the IAP memory performance that could explain, at least in part, the reverse asymmetries reported in different studies. [ABSTRACT FROM AUTHOR]

Stress is a risk factor for cardiovascular diseases in the general population. Epilepsy has been considered a suitable model of chronic stress with a higher incidence of cardiovascular mortality than the general population. This study provides preliminary data about cardiovascular response to a cognitive stressor and a neuropsychological assessment in patients with epilepsy. It also explores the relationship between cardiovascular response and cognitive performance, depending on the side of seizure focus. Thirty-five patients with drug-resistant epilepsy, 17 with epileptogenic area (EA) in the left hemisphere (LH) and 18 with EA in the right hemisphere (RH), underwent a cognitive stressor and a neuropsychological assessment. The cardiovascular response was recorded throughout both conditions. Results showed that a long-lasting neuropsychological assessment was capable of producing a hemisphere-modulated cardiovascular response with heart rate (HR) decreases (and R-R interval increases) more pronounced in the LH patients than in the RH patients at the postassessment period (p = .05 and p = .01, respectively). The hemisphere of EA moderated the relationship between cardiovascular response and cognitive performance (for all, p < .03). Our findings may have clinical implications from a preventive perspective since the EA hemisphere may be a relevant factor for coping with stress in people with drug-resistant epilepsy. [ABSTRACT FROM AUTHOR]

Article 7 of the Convention on the Rights of the Child declares the right of every child to be registered after birth and to acquire a nationality. The "invisible children", referred in this article, are born in the course of their mothers' migratory journey -- between the country of origin and the country of destination --, without a birth certificate or registration. This circumstance subsequently prevents them from acquiring an identity and a nationality, becoming therefore statelessness. This article analyzes the instruments of the Spanish legal system to avoid childhood statelessness in these cases. [ABSTRACT FROM AUTHOR]

The purpose of this study is to analyze the level of technological competence that students of the Bachelor's Degree in Early Childhood Education have. The research is developed under a quantitative approach, a descriptive scope, with a non-experimental design. The results allowed to know the skills that students have in the face of ICT, where it is evidenced that they have a good command of the tools and that they apply them to their pedagogical practices. Furthermore, these findings show aspects in which this competence must be strengthened in order to achieve a high integration of ICT in the educational processes. [ABSTRACT FROM AUTHOR]

Seasonal dry tropical forest (STDF) is a widespread vegetation type in western Mexico. Generally, this type of forest develops in semihumid habitats where lacustrine basins are scarce, preventing documentation of the vegetation history and forest dynamics using a paleoecological approach. Here, we present a palynological record from the Santa Maria del Oro crater lake, located within the distribution area of the STDF and the adjacent dry oak forest which gives insight into the changes in diversity and human impact at this tropical site. Pollen data, in combination with geochemical analysis and microcharcoal data from a lacustrine sequence, are used to discuss vegetation change and diversity in the plant assemblages related to drought or anthropogenic activity over the last 5000 years. Our results show three distinct periods of drought in the basin, from 4200 to 3850, 3100 to 2300, 1570 to 1100 and 300 cal year BP, with changes in vegetation composition mainly related to a decrease in taxa diversity during these periods. Based on the presence of maize pollen, two periods of human activity (3790–2160 and 280 cal year BP to present) were detected with an increase in herbaceous pollen used as a surrogate for deforestation. These two disturbance periods, pre-Columbian and postcolonial, occurred during wet conditions in the basin. Our results highlight the correlation between El Niño events, drought and fire with changes in the composition and diversity of STDF. [ABSTRACT FROM AUTHOR]

The purpose of this study is to analyze the level of technological competence that students of the Bachelor's Degree in Early Childhood Education have. The research is developed under a quantitative approach, a descriptive scope, with a non-experimental design. The results allowed to know the skills that students have in the face of ICT, where it is evidenced that they have a good command of the tools and that they apply them to their pedagogical practices. Furthermore, these findings show aspects in which this competence must be strengthened in order to achieve a high integration of ICT in the educational processes. [ABSTRACT FROM AUTHOR]

AbstractObjective: Drug-resistant temporal lobe epilepsy (TLE) is a neurological disorder characterized by cognitive deficits. This study examined whether patients with TLE and different cognitive phenotypes differ in cortisol levels and affectivity while controlling for demographic and clinical variables. Methods: In this cross-sectional study, 79 adults with TLE underwent neuropsychological evaluation in which memory, language, attention/processing speed, executive function, and affectivity were assessed. Six saliva samples were collected in the afternoon to examine the ability of the hypothalamic-pituitary-adrenal (HPA) axis to descend according to the circadian rhythm (C1 to C6). The cortisol area under the curve concerning ground (AUCg) was computed to examine global cortisol secretion. Results: Three cognitive phenotypes were identified: memory impairment, generalized impairment, and no impairment. The memory-impairment phenotype showed higher cortisol levels at C4, C5, and C6 than the other groups (p = 0.03, η2 = 0.06), higher cortisol AUCg than the generalized-impairment phenotype (p = 0.004, η2 = 0.14), and a significant reduction in positive affectivity after the evaluation (p = 0.026, η2 = 0.11). Higher cortisol AUCg and reductions in positive affectivity were significant predictors of the memory-impairment phenotype (p < 0.001; Cox and Snell R2 = 0.47). Conclusions: Patients with memory impairment had a slower decline in cortisol levels in the afternoon, which could be interpreted as an inability of the HPA axis to inhibit itself. Thus, chronic stress may influence hippocampus-dependent cognitive function more than other cognitive functions in patients with TLE. [ABSTRACT FROM AUTHOR]

Three-dimensional urban cartography is needed for city changes' assessment. The variety of studies using 3D calculations of urban elements grows each year. Building and vegetation volumes are necessary to assess and understand spatio-temporal urban changeable environments. However, there are technical questions as to which method can improve 3D urban cartographic accuracy. The innovative part of this current study is the creation of a six-band hybrid obtained from LIDAR and WorldView2 synergy. Two different enhancement algorithms demonstrated the most important spectral features for the urban development and vegetation classes. Results indicated an improvement in accuracy by up to 21.3%, according to the Kappa coefficient. Both infra-red band and intensity band were the most significant, according to the principal components analysis. The synergy delimited classes and polygons, as well as the direct display of information regarding heights of elements and improving the extraction of roads, buildings and vegetation classes. [ABSTRACT FROM AUTHOR]

Abstract Diatom-based transfer functions for salinity, precipitation and temperature were developed using a training set that included data from 40 sites along central Mexico. These transfer functions showed good performance parameters and were subsequently applied to the previously published diatom record from lake Chalco, southern Basin of Mexico. Heinrich stadials (HS-3 to HS-0) were reconstructed as cold and dry events, with HS-2 representing the coldest and driest conditions, while HS-1 shows a complex bimodal cooling pattern. Orbital scale variability is also recorded. High and variable lake salinities from ∼34 to 29 ka BP (marine isotope stage 3, MIS-3) corresponded with times of maximum summer insolation and evidences of frequent fires. MIS-2 was identified as a cold period, with low lake salinity associated with low evaporation, with two cold intervals during the minima in spring (∼25.5 ka BP) and summer (∼20 ka BP) insolation. The ∼20 ka BP cold event together with HS-2 (24-23 ka BP), defined a bimodal maximum cooling during the last glacial maximum (LGM: 24.5–19.5 ka BP) within the range of pollen-based estimates, further supporting a maximum tropical cooling of 4–5 °C for the LGM. The deglacial (19.5–11.5 ka BP) showed the highest precipitation anomalies with three peaks that closely correlated with glacier advances in the nearby mountains (Iztaccihuatl). The early Holocene marked a change towards high lake salinities and the highest positive temperature anomalies (+3.5 °C) during a peak in summer insolation. Even though at orbital scale Chalco showed a nearly opposite trend to the record from the more southerly lake Peten-Itza (Guatemala), at millennial scale it showed a common pattern of cold and dry conditions during HSs, comparable to other tropical latitude sites in the northern hemisphere and further supporting the idea that there is a strong coupling between tropical and higher latitudes climates, in particular with the North Atlantic. Highlights • Diatom-based transfer functions produced a ∼40 ka BP paleoclimatic reconstruction for central Mexico. • Orbital and millennial scale events were identified in the salinity, precipitation and temperature reconstructions. • Maximum last glacial cooling of ∼5°C is reconstructed, a relatively wet deglacial and a warmer (+3.5°C) early Holocene. • Heinrich stadials (3 to 0) are cold and dry; HS2 was the coldest while HS-1 showed a bimodal cooling. [ABSTRACT FROM AUTHOR]

The current gold standard assessment of human inspiratory muscle function involves using invasive measures of transdiaphragmatic pressure (Pdi) or crural diaphragm electromyography (oesEMGdi). Mechanomyography is a non-invasive measure of muscle vibration associated with muscle contraction. Surface electromyogram and mechanomyogram, recorded transcutaneously using sensors placed over the lower intercostal spaces (sEMGlic and sMMGlic respectively), have been proposed to provide non-invasive indices of inspiratory muscle activation, but have not been directly compared to gold standard Pdi and oesEMGdi measures during voluntary respiratory manoeuvres. To validate the non-invasive techniques, the relationships between Pdi and sMMGlic, and between oesEMGdi and sEMGlic were measured simultaneously in 12 healthy subjects during an incremental inspiratory threshold loading protocol. Myographic signals were analysed using fixed sample entropy (fSampEn), which is less influenced by cardiac artefacts than conventional root mean square. Strong correlations were observed between: mean Pdi and mean fSampEn |sMMGlic| (left, 0.76; right, 0.81), the time-integrals of the Pdi and fSampEn |sMMGlic| (left, 0.78; right, 0.83), and mean fSampEn oesEMGdi and mean fSampEn sEMGlic (left, 0.84; right, 0.83). These findings suggest that sMMGlic and sEMGlic could provide useful non-invasive alternatives to Pdi and oesEMGdi for the assessment of inspiratory muscle function in health and disease. [ABSTRACT FROM AUTHOR]

Introduction The sign of the cross (SC) is a catholic ritual that has been described as an automatism during the ictal phase in patients with right temporal lobe epilepsy. Objective The study aimed to describe the prevalence of the SC and analyze the characteristics of patients who presented this phenomenon during the video-electroencephalography (VEEG) admission in our Epilepsy department. Methods This is a retrospective analysis of 1308 recorded seizures; 14 patients presented the SC during the admission. Seizure semiology, electroencephalography (EEG), etiology, neuroimaging, and surgical findings were analyzed. Results A prevalence of 1.1% was found, and the sign was not only an ictal finding (21% was postictal) but also exclusive of patients with temporal lobe epilepsy (15% were extratemporal) in contrast to what has been reported so far. The localizing and lateralizing value of the ictal SC was low (sensitivity 75%, specificity 33.3%, positive predictive value 60%, negative predictive value 50% for a right temporal epileptogenic zone (EZ)) compared with other previously described signs. Regardless of the lateralization of the EZ, the sign was always performed with the right hand supporting the hypothesis of a possible learned behavioral automatism. Conclusion The SC is a rare ictal or postictal manifestation that occurs in patients with temporal and extratemporal epilepsies without clear localizing and lateralizing value compared with previously described signs. [ABSTRACT FROM AUTHOR]

The recognition of past climatic fluctuations in sedimentary sequences in central Mexico is relevant for understanding the forcing mechanisms and responses of climatic system in the northern American tropic. Moreover, in this active volcanic setting the sedimentary record preserves the history of past volcanic activity. Climatic and environmental variability has been documented for the last tenths of thousands of years from the upper lacustrine sediments in Chalco basin. A series of cores drilled down to 122 m depth in this basin offer a long, continuous and high resolution record of past climatic changes of the last ca. 150 kyr in this region. Here we present the detailed lithostratigraphy and some physical properties (magnetic susceptibility and density) of the master sequence. Sedimentary components and their abundance were identified and quantified in smear slides and direct core observations. Age model is based on 13 14 C and one 230 Th/U dates. Based on their facies association seven lithostratigraphic units were defined, which reflect the main stages of lake Chalco evolution. These phases closely match the marine isotopic stages. The data reveal that at the end of MIS6 Chalco was a relatively deep and stratified freshwater lake. During MIS5 the depositional environment fluctuated between low lake stands to marshy and marginal playa settings with sporadic flooding events, and severe arid periods resulted in aerial exposure of lake sediments. Low lake stands persisted during MIS4 and MIS3, with minor fluctuations towards slightly deeper phases. The Last Glacial Maximum (LGM) and the deglacial period (21-13 kyr) are characterized by intense volcanism. The early and mid-Holocene high calcareous content and alkaline-subsaline lake suggest dry conditions. The fluctuations of lake levels inferred provide the basis for future paleoclimatic works. [ABSTRACT FROM AUTHOR]

Question When did vegetation assemblages that occupy modern central Mexico appear within the context of the late Quaternary? Location Central Mexico. Methods We used modern and fossil pollen data sets from central Mexico to explore the evolution of regional vegetation through the late Quaternary. A total of 1397 samples (1357 fossil samples distributed in 17 records and 40 modern samples) were analysed through detrended correspondence analysis to evaluate the degree of analogy between modern and past vegetation assemblages, and regional vegetation compositional turnover through time. Results There was a high degree of analogy between modern and glacial vegetation, whereas the early and mid-Holocene were characterized by a high frequency of no-modern-analogue pollen assemblages. Vegetation turnover during the glacial time was characterized by both pulses of abrupt change and episodes of stability. In contrast, vegetation turnover was high through most of the Holocene. Both vegetation turnover and past vegetation analogy to modern were not synchronous in altitudinal zones, except for the past 2000 yrs, when pollen assemblages suggest a high vegetation analogy to modern-day throughout the region. Conclusions Human impacts on central Mexico regional vegetation were consistently evident during the last 2000 yrs, suggesting that biodiversity expressed in the modern vegetation assemblages incorporates a high anthropogenic imprint. High resemblance of glacial and modern landscapes suggests that the effect of human occupation on the landscape is similar to that exerted by glacial time environmental stress. However, loss of ecosystem connectivity under the modern pattern of landscape homogenization represents an unprecedented threat for regional biodiversity. [ABSTRACT FROM AUTHOR]

This paper presents a short description of the coring operations undertaken to recover the full lacustrine sedimentary sequence from Chalco. Geophysical techniques were used to determine the distribution and thickness of the sediments in order to select the drilling site. Resonance frequencies determined from H/V spectral ratios were used to determine an area where lake sediments reached 300 m thickness. Electromagnetic survey showed two changes in electric resistivity which were related to changes in sediment composition, the first from 100 to 120 m, related to an increase in volcanoclastic sediments and the second from 330 to 400 m related to the presence of a basaltic flows. Three wells were drilled with continuous recovery, reaching depths of 420 m in well A, 310 in B and 520 in C. Samples for geomicrobiological and metagenomics studies were collected during drilling operations. A total of 1152 m of core sediments were recovered reaching a maximum depth of 520 m. Recovery percentages were between 88 and 92 % in the three wells. Magnetic susceptibility analyses in the three sequences show that the first 260 m are mostly lake sediments, between 260 and 300 m sediments are coarser and below 300 m they are mostly volcaniclastic. Analysis of the sedimentary sequence of Lake Chalco that covers the last ~300000 years will allow documenting and extending the knowledge of climate variability in area, the paleoenvironmental history, basin closure history, lacustrian system development and volcanic activity recurrence. Studies of the physical properties of this sequence will be important for seismic propagation and basin structure modeling, and also will improve modeling of the subsidence process that this region experiences. [ABSTRACT FROM AUTHOR]

Paleolimnological studies require a broad understanding of the geometry and depth of the sedimentary fill of lake basins prior to coring campaigns. Seismic methods are routinely employed for the indirect characterization of lake-bottom sediments. However, the use of seismic methods might occasionally be limited due to surface conditions or poor seismic contrasts between the stratigraphic units, which lead to data quality that is too poor to provide sufficient information for the selection of drill sites. Sources of cultural noise are one of the main reasons why seismic methods fail in study areas near or within large cities, such as Mexico City. Under certain conditions, electrical and electromagnetic methods might be a suitable substitute or complement to seismic exploration, as they respond to different physical properties of the subsurface. To evaluate the applicability of such methods, here we present two recent case studies from the desiccated lakes Chalco and Xochimilco both located in urban areas within the Basin of Mexico where electrical resistivity tomography (ERT), transient electromagnetic (TEM) and magnetotelluric (MT) soundings were conducted for the characterization of lake basement and lacustrine sediments. In both examples, the results of the geophysical exploration contributed valuable stratigraphic information for the following drilling and core recovery, which highlights the potential of electrical and electromagnetic methods in paleolimnological studies. [ABSTRACT FROM AUTHOR]

Background: A thorough analysis of continuous adventitious sounds (CAS) can provide distinct and complementary information about bronchodilator response (BDR), beyond that provided by spirometry. Nevertheless, previous approaches to CAS analysis were limited by certain methodology issues. The aim of this study is to propose a new integrated approach to CAS analysis that contributes to improving the assessment of BDR in clinical practice for asthma patients. Methods: Respiratory sounds and flow were recorded in 25 subjects, including 7 asthma patients with positive BDR (BDR+), assessed by spirometry, 13 asthma patients with negative BDR (BDR-), and 5 controls. A total of 5149 acoustic components were characterized using the Hilbert spectrum, and used to train and validate a support vector machine classifier, which distinguished acoustic components corresponding to CAS from those corresponding to other sounds. Once the method was validated, BDR was assessed in all participants by CAS analysis, and compared to BDR assessed by spirometry. Results: BDR+ patients had a homogenous high change in the number of CAS after bronchodilation, which agreed with the positive BDR by spirometry, indicating high reversibility of airway obstruction. Nevertheless, we also found an appreciable change in the number of CAS in many BDR- patients, revealing alterations in airway obstruction that were not detected by spirometry. We propose a categorization for the change in the number of CAS, which allowed us to stratify BDR- patients into three consistent groups. From the 13 BDR- patients, 6 had a high response, similar to BDR+ patients, 4 had a noteworthy medium response, and 1 had a low response. Conclusions: In this study, a new non-invasive and integrated approach to CAS analysis is proposed as a high-sensitive tool for assessing BDR in terms of acoustic parameters which, together with spirometry parameters, contribute to improving the stratification of BDR levels in patients with obstructive pulmonary diseases. [ABSTRACT FROM AUTHOR]

A thorough knowledge of the effects of climate and land use changes on the soil carbon pool is critical to planning effective strategies for adaptation and mitigation in future scenarios of global climate and land use change. In this study, we used CarboSOIL model to predict changes in soil organic carbon stocks in a semi-natural area of Southern Spain in three different time horizons (2040, 2070, 2100), considering two general circulation models (BCM2 and ECHAM5) and three IPCC scenarios (A1b, A2, B2). The effects of potential land use changes from natural vegetation (Mediterranean evergreen oak woodland) to agricultural land (olive grove and cereal) on soil organic carbon stocks were also evaluated. Predicted values of SOC contents correlated well those measured (R2 ranging from 0.71 at 0–25 cm to 0.97 at 50–75 cm) showing the efficiency of the model. Results showed substantial differences among time horizons, climate and land use scenarios and soil depth with larger decreases of soil organic carbon stocks in the long term (2100 time horizon) and particularly in olive groves. The combination of climate and land use scenarios (in particular conversion from current ‘dehesa’ to olive groves) resulted in yet higher losses of soil organic carbon stocks, e.g. − 30, − 15 and − 33% in the 0–25, 25–50 and 50–75 cm sections respectively. This study shows the importance of soil organic carbon stocks assessment under both climate and land use scenarios at different soil sections and point towards possible directions for appropriate land use management in Mediterranean semi natural areas. [ABSTRACT FROM AUTHOR]

Soil management has important effects on soil properties, runoff, soil losses and soil quality. Traditional olive grove (OG) management is based on reduced tree density, canopy size shaped by pruning and weed control by ploughing. In addition, over the last several decades, herbicide use has been introduced into conventional OG management. These management strategies cause the soil surface to be almost bare and subsequently high erosion rates take place. To avoid these high erosion rates several soil management strategies can be applied. In this study, three strategies were assessed in OG with conventional tillage in three plots of 1 ha each. Soil properties were measured and soil erosion rates were estimated by means of the RUSLE model. One plot was managed with no amendments (control), and the other two were treated with olive leaves mulch and oil mill pomace applied yearly from 2003 until 2013. The control plot experienced the greatest soil loss while the use of olive leaves as mulch and olive mill pomace as an amendment resulted in a soil loss reduction of 89.4% and 65.4% respectively (assuming a 5% slope). In addition, the chemical and physical soil properties were improved with the amendments. This combined effect will created a higher quality soil over the long term that it is more resilient to erosion and can provide better ecosystem services, as its functions are improved. [ABSTRACT FROM AUTHOR]

Land use change from natural vegetation to agricultural land often affects the properties and quality of soils. A field study was conducted to determine the effects of land use change [Mediterranean evergreen oak woodland (MEOW-dehesa) to olive grove and cereal] on soil organic carbon (SOC) and nitrogen (N) concentrations and stocks, and on the soil quality in Cambisols in The Cardeña-Montoro Nature Reserve (South Spain). The land use change from MEOW-dehesa to olive groves increased the SOC concentration (MEOW-dehesa: 19.4 g kg −1 ; 7.2 g kg −1 ; olive grove: 41.8 g kg −1 ; 15.4 g kg −1 in the surface and subsurface layers respectively) and stock (22.3% higher in olive grove than in MEOW-dehesa and 17% higher in olive grove than in cereal), but did not affect the N concentration and decreased N stock in the surface layer. The conversion from MEOW-dehesa to cereal did not affect SOC stock and concentration; it only decreased the N concentration and stock in the surface layer (N: 1.6 g kg −1 and 1.1 g kg −1 in MEOW-dehesa and cereal respectively; N stock 4.2 Mg ha −1 and 2.9 Mg ha −1 in MEOW-dehesa and cereal respectively). After the land use change to olive grove stratification ratios increased, however in cereal they decreased. Comparing the different types of MEOW-dehesa, significant differences were found. It is important to point out that all the stratification ratios calculated were >2. [ABSTRACT FROM AUTHOR]

Testate amoebae are common single-celled eukaryotic organisms in aquatic ecosystems. Despite their important role in these ecosystems, and their potential as bioindicators and paleoindicators, they remain poorly studied in Mexico. The major objectives of this study were to: 1) increase knowledge of testate amoebae in Mexico's tropical lakes, and 2) create a catalog of high-quality scanning electron micrographs that can be used for future ecological and paleoenvironmental studies. We collected surface-sediment samples from 29 lakes, located in the Transmexican Volcanic Belt, one at each lake during June and October 2011, and March 2013. Sediments were collected with an Ekman grab and preserved in anhydrous ethanol. Sub-samples were observed under a stereomicroscope and morphometric data for each species were recorded. Total diameter and aperture diameter were measured on circular tests. Irregularly shaped tests were measured for length and width of the aperture and for the size of the whole test. If a specimen possessed spines, the length of one randomly selected spine was measured. The best-preserved specimen of each taxon was photographed with an optical microscope and a scanning electron microscope (SEM). We found 41 taxa of testate amoebae belonging to the genera: Arcella, Argynnia, Centropyxis, Cucurbitella, Cyclopyxis, Cyphoderia, Difflugia, Euglypha, Lesquereusia, Pentagonia, Pseudodifflugia and Scutiglypha. Twelve species not previously reported for Mexico were recorded, along with 13 varieties. The average number of taxa recorded in each lake was eight, and the highest taxonomic richness was 18. The taxon found in the greatest number of lakes was Centropyxis aculeata var. aculeata. Taxonomic richness varied among lakes in the same region. This could reflect lake-specific differences in environmental conditions, underscoring the need for more detailed studies that include collection of data on physical and chemical variables in the lakes. Our results highlighted the need of further studies for the distribution patterns and ecology of lacustrine testate amoebae. [ABSTRACT FROM AUTHOR]

Soil organic carbon (SOC) plays a critical role in the global carbon (C) cycle, and C sequestration in forest soils can represent a C sink. A relevant question is how does SOC changes in space and time; consequently, the study of the influence of topographic aspect on SOC stocks (SOCS) is very important to build a complete understanding of the soil system. In this line, four topographic aspects, north (N), south (S), east (E) and west (W) were studied under two different plant communities; native forests (NF) and reforested areas (RF) in the Despeñaperros Natural Park (S Spain). Five soil profiles were sampled at each of six different sites, 2 sites for NF (N and E) and 4 sites for RF (N, S, E and W). Soil properties were studied at different depths using soil control sections (S1: 0–25 cm; S2: 25–50 cm; S3: 50–75 cm). The results indicate that RF (N: 147.1 Mg ha − 1 ; E: 137.3 Mg ha − 1 ; W: 124.9 Mg ha − 1 and S: 87.0 Mg ha − 1 ) had increased total SOCS compared to NF (N: 110.4 Mg ha − 1 and E: 80.9 Mg ha − 1 ), and that SOCS in the N position were higher than in the other topographic aspects. Therefore, the results suggest that topographic aspect should be included in SOCS models and estimations at local and regional scales. [ABSTRACT FROM AUTHOR]

A new detailed pollen record of the penultimate glacial–interglacial–glacial cycle corresponding to the late marine isotopic stages (MISs) 6–3 (146–35 ka ago) has been obtained from Lake Chalco, in the Basin of Mexico. This record provides an insight into vegetation dynamics and climate variability at the northern limit of the American tropics. The pollen record displays a high temporal resolution with a mean sampling interval of ∼230 years. The changes in plant composition were reconstructed by pollen analysis and differences in plant composition between distinct periods were established. The wettest cold stage, indicated by a combination of diverse open vegetation and mesophytic taxa correlates with the penultimate late glacial MIS 6 (146–130 ka), when Lake Chalco was a deep freshwater lake. The penultimate interglacial MIS 5e (126.5–123.6 ka) shows a dominance of Pinus forests, with tropical taxa suggesting warmer than present conditions; environmental proxies indicate drier conditions and that the lake transitioned into a saline water body. Open communities and Pinus and Quercus forests with mesophytic taxa and, during the stadial periods, MIS 5 d, 5c, and 5 b (125–90 ka), with tropical taxa, characterize the record of interstadials. Pinus -dominated forests characterize the landscape during MIS 5a. MIS 5c to MIS 3 showed lower and variable evenness and palynological richness, along with an increase in fire activity. During MIS 4 and 3, a trend towards drier conditions was also recorded with enhanced carbonate precipitation and proxies indicating saline conditions. Tree-line changes in response to climate change and taxa migration were documented. A comparison with long records from the Greenland ice cores, the marine Cariaco Basin and insolation parameters revealed that the pollen data and the Pinus pollen accumulation rates evidence the response of the vegetation to glacial and interglacial changes and to millennial-scale variability. Wetter conditions were inferred to exist during the Greenland interstadials, while drier conditions persisted during Heinrich events. • Changes in plant composition and diversity in the Basin of Mexico encompassing late MIS 6 to MIS 3. • High taxonomic diversity and cold conditions characterize the late MIS 6 landscape. • Pinus forests with variable evenness and drier environments from the end of MIS 5 to MIS 3. • Pollen data highlight the influence of millennial-scale climate variability on plant communities. [ABSTRACT FROM AUTHOR]

We present a palaeohydrological reconstruction of Lake Chalco from 70 to 11.5 ka BP based on ostracod records consisting of three species: Limnocytherina axalapasco, Candona patzcuaro , and Cypridopsis vidua. Overall, the presence of these species helped investigate Lake Chalco water level fluctuations, and thus water salinity variations. Moreover, this work helped improve our knowledge of L. axalapasco and Candona alchichica , two endemic species of Central Mexico, the latter of which was replaced by C. patzcuaro after the cold and dry MIS4. Five ostracod zones reflect the main environmental changes that occurred during the Late Pleistocene. During 70–62 ka BP (Zone 5), shallow and very variable salinity conditions were inferred with a possible occupancy of submerged macrophytes. The Lake Chalco water level increased from 62 to 49 ka BP (Zone 4) and relatively less saline conditions were inferred. The warmer period from of 49–39 ka BP (Zone 3) was characterised by lower lake levels and a gradually increasing salinity. The evaporation rates continued to increase during 39–27 ka BP (Zone 2). However, a higher runoff input helped maintain a relatively high lake level. Later on, cold and dry conditions from 27 to 11.5 ka BP (Zone 1) inhibited the ostracod occupancy in Lake Chalco. • Paleoenvironmental reconstruction of Lake Chalco based on ostracod record from 70 to 11.5 ka BP. • Lake water salinity changes correlate with ostracod relative abundances changes. • Replacement of Candona alchichica by Candona patzcuaro after the cold and dry MIS4. [ABSTRACT FROM AUTHOR]

We inferred millennial-scale climate variations and paleohydrological conditions in the northern sector of the American tropics for 30.3–5.5 cal ka BP using geochemical characteristics of sediments from Lake Chalco in central Mexico. The sediment sequence is chronologically constrained with three tephra and nine radiocarbon dates. Temporal variations in titanium, total inorganic carbon, total organic carbon/titanium ratio, carbon/nitrogen ratio, and silica/titanium ratio indicate changes in runoff, salinity, productivity, and sources. Higher concentrations of Ti indicate more runoff during latest Marine Isotope Stage (MIS) 3 (30.3–28.6 cal ka BP). Runoff was lower during the last glacial maximum (LGM; 23–19 cal ka BP) than during the Heinrich 2 event (26–24 cal ka BP). The interval of reduced runoff continued up to 17.5 cal ka BP but increased during the Bølling/Allerød. Trends of decreasing runoff and increasing salinity are observed throughout MIS 1. Lake Chalco received less runoff during the LGM compared to deglaciation, opposite the trend of other North American tropical records. Different amounts of rainfall at different sites are possibly due to shifts in the position of the Intertropical Convergence Zone, changes in the size of the Altlantic warm pool, and varying sea-surface temperatures of the Atlantic and Pacific oceans. [ABSTRACT FROM AUTHOR]

The ostracode fauna of the neartic-neotropical transitional zone has remained poorly known until this study. Ten ostracode species inhabit ten highland lakes (five maar lakes (phreatic/phreato-magmatic explosion origin), one volcanic-tectonic lake, three natural dams and one man-made dam) in East-central Mexico. Surface sediments from the deepest part and the littoral zone from all studied lakes were collected. Environmental variables (pH, temperature, dissolved oxygen, conductivity, TDS) were measured in situ and parallel water samples for chemical analysis were collected for habitat description. Widely distributed species in the study area (=5 lakes) include Cypridopsis vidua, Darwinula stevensoni and Eucandona cf. patzcuaro. Limnocytherina axalapasco is an endemic species and was collected in three maar lakes and in one man-made dam. Rare species included: Chlamydotheca arcuata?, Fabaeformiscandona acuminata?, Ilyocypris gibba?, Limnocythere friabilis?, Potamocypris smaragdina? and Potamocypris unicaudata?. Highest species richness (6 spp.) was found in the large and shallow Lake Metztitlán (2.6km2, 5.5m deep), with the lake water type HCO3 ->>SO4 ²->Cl- -- Ca2+>Na+>Mg2+. The rest of studied lakes (<63m, <27km²) had not more than three species. For instance, only two ostracode species were collected in Lake Alchichica, which is the largest, deepest and most saline studied maar lake. [ABSTRACT FROM AUTHOR]

Soil organic carbon (SOC) is an important part of the global carbon (C) cycle. In addition, SOC is a soil property subject to changes and highly variable in space and time. Over time, some researches have analyzed entire soil profile (ESP) by pedogenetic horizons and other researches have analyzed soil control sections (SCS) to different thickness. However, very few studies compare both methods (ESP versus SCS). This research sought to analyze the SOC stock (SOCS) variability using both methods (ESP and SCS) in The Despeñaperros Natural Park, a nature reserve that consists of a 76.8 km 2 forested area in southern Spain. Thirty-four sampling points were selected in the study zone. Each sampling point was analyzed in two different ways, as ESP (by horizons) and as SCS with different depth increments (0–25, 25–50, 50–75 and 75–100 cm). The major goal of this research was to study the SOCS variability at regional scale. The soils investigated in this study included Phaeozems, Cambisols, Regosols and Leptosols. Total SOCS in the Despeñaperros Natural Park was over 28.2% greater when SCS were used compared to ESP, ranging from 0.8144 Tg C (10,604.2 Mg km −2 ) to 0.6353 Tg C (8272.1 Mg km −2 ) respectively (1 Tg = 10 12 g). However, when the topsoil (surface horizon and superficial section control) was analyzed, this difference increased to 59.8% in SCS compared to ESP. The comparison between ESP and SCS showed the effect of mixing pedogenetic horizons when depth increments were analyzed. This indicates an overestimate of T-SOCS when sampling by SCS. [ABSTRACT FROM AUTHOR]

Soil organic carbon (SOC) is extremely important in the global carbon (C) cycle as C sequestration in non-disturbed soil ecosystems can be a C sink and mitigate greenhouse-gas-driven climate change. Soil organic carbon changes in space and time are relevant to understand the soil system and its role in the C cycle. This is why the influence of topographic position on SOC should be studied. Seven topographic positions from a toposequence between 607 and 1168 m were analyzed in the Despeñaperros Natural Park (Jaén, SW Spain). Depending on soil depth, one to three control sections (0-25, 25-50 and 75 cm) were sampled at each site. The SOC content in studied soils was below 30 g kg-1 and strongly decreases with depth. These results were related to the gravel content and to the bulk density. The SOC content from the topsoil (0-25 cm) varied largely through the altitudinal gradient ranging between 27.3 and 39.9 g kg-1. The SOC stock (SOCS) varied between 53.8 and 158.0 Mg ha-1 in the studied area, which had been clearly conditioned by the topographic position. Therefore, results suggest that elevation should be included in SOCS models and estimations at local and regional scales. [ABSTRACT FROM AUTHOR]

The aim of this investigation is to analyse the traditional use that inhabitants of the National Park El Tepozteco give to wild mammals in the area. Several ethnozoological techniques were used, such as participant observation, structured questionnaires, thorough interviews and guided tours. The results indicate that the wild mammal hunting takes place all year long in the morning or at night, individually or collectively. Were identified 34 species distributed in seven orders, from them 17 species fall into a 'usage category' fulfilling needs such as meat, skin, claws, paws and fat. The families presenting the most species within a usage category are: Procyonidae, Mephitidae, Felidae y Sciuridae. Were recognized seven usage categories: food supply (58.8%), crafts (58.8%), medicine (23.5%), ornament (17.6%), pets (17.6%), mystical-religious (11.7%) and manure (5.8%). The mammals with a major value rate are: white-tailed deer (0.037), wild rabbit (0.022), badger (0.022), and racoon (0.022). The National Park El Tepozteco has social-environmental issues which stem from the impacts of economic policies on the natural resources and the development of indigenous and rural communities. However, the original inhabitants of the area still possess certain knowledge that translates into the traditional use of wild mammals, whose handling is determined by the already assigned usage categories. It is advisable to set up breeding farms or hatcheries for these multi-use mammal species in the National Park El Tepozteco, action that will also regulate and promote a better and integral handling [ABSTRACT FROM AUTHOR]

In Mediterranean areas, through the years, natural forest (NF) areas have suffered land use change (LUC) mainly for economic reasons. This is the case of olive groves (OG) in Andalusia (south Spain), the main olive oil production area in the world. This LUC from NF to OG has caused soil erosion and the loss of soil quality. Also, this effect has been aggravated by climatic conditions and poor soil management practices. A field study was conducted to examine the effects of LUC from NF to OG in a toposequence (summit-SM, backslope-BS and toeslope-TS) and to determine soil organic carbon (SOC), nitrogen (N) and the stratification ratio (SR) of SOC in the Torredelcampo–Jaen–Spain (Mediterranean area) in a Calcisols–Regosols–Vertisols sequence. Total SOC (T-SOC) was low for both NF and OG soils. In the case of NF, there was a pattern of decrease from the highest (SM) to the lowest topographical position (TS); whereas for OG, the highest T-SOC was found in TS (50.2 ± 1.1 g kg −1 ). T-SOC was more than 40% higher in NF than in OG in SM and BS. The total SOC stock (T-SOCS) in NF soils remained evenly distributed in the three topographical positions. However, the trend for the OG soils was an increase of T-SOCS along the hillside (SM: 68.9 ± 4.8 Mg ha −1 ; BS: 82.3 ± 12.3 Mg ha −1 and TS: 158.7 ± 15.4 Mg ha −1 ). N followed a pattern of decrease with depth in the OG soils, but not in NF soils. As for N stock, it was higher in NF than in OG, with the exception of NF-TS and OG-TS. SR values in NF had a general trend of increasing from higher to lower topographical positions, despite the fact that T-SOC decreased from higher to lower topographical positions. This indicates that soil quality is higher in lower topographical positions even though there is less T-SOC. SR values in OG soils had a similar trend as in NF soils (but with lower values). However, T-SOC increased as well in the same way, which was opposite to the NF soils case. Therefore, soil quality was higher in lower topographical positions for both land uses. [ABSTRACT FROM AUTHOR]

Understanding of tillage effects on soil chemical properties and cations in soil solution dynamics is essential for making appropriate land-management decisions. Measurements were made after more than 25 years of different tillage treatments: conventional tillage (CT) and conservation tillage, which includes no-till (NT) and minimum tillage (MT). pH and bulk density did not show important changes but exchangeable cations and cations in soil solution were affected by depth and different tillage. The highest concentration of exchangeable Ca2+and Mg2+was found in NT, decreased in MT and the lowest concentration was found in CT (mean values were 26.0, 24.4 and 23.3 cmolckg−1for exchangeable Ca2+and 4.2, 3.7 and 3.3 cmolckg−1for exchangeable Mg2+in NT, MT and CT, respectively). In addition, the highest concentration of exchangeable Na+was found in NT, decreased in CT and the lowest concentration was found in MT. However, the highest concentration of exchangeable K+was found in MT. A significant depth effect was observed for cations in soil solution: Na+increased with depth whereas K+and Ca2+decreased with depth. This study aims to demonstrate the effect of tillage on the distribution and concentration of certain chemical soil properties. [ABSTRACT FROM PUBLISHER]

Abstract: Background: Existing air quality monitoring programs are, on occasion, not updated according to local, varying conditions and as such the monitoring programs become non-informative over time, under-detecting new sources of pollutants or duplicating information. Furthermore, inadequate maintenance may cause the monitoring equipment to be utterly deficient in providing information. To deal with these issues, a combination of formal statistical methods is used to optimize resources for monitoring and to characterize the monitoring networks, introducing new criteria for their refinement. Methods: Monitoring data were obtained on key pollutants such as carbon monoxide (CO), nitrogen dioxide (NO2), ozone (O3), particulate matter (PM10) and sulfur dioxide (SO2) from 12 air quality monitoring sites in Seville (Spain) during 2012. A total of 49 data sets were fit to mixture models of Gaussian distribution using the expectation–maximization (EM) algorithm. To summarize these 49 models, the mean and coefficient of variation were calculated for each mixture and carried out a hierarchical clustering analysis (HCA) to study the grouping of the sites according to these statistics. To handle the lack of observational data from the sites with unmonitored pollutants, the missing statistical values were imputed by applying the random forests technique and then later, a principal component analysis (PCA) was carried out to better understand the relationship between the level of pollution and the classification of monitoring sites. All of the techniques were applied using free, open-source, statistical software. Results and conclusion: One example of source attribution and contribution is analyzed using mixture models and the potential for mixture models is posed in characterizing pollution trends. The mixture statistics have proven to be a fingerprint for every model and this work presents a novel use of them and represents a promising approach to characterizing mixture models in the air quality management discipline. The imputation technique used is allowed for estimating the missing information from key unmonitored pollutants to gather information about unknown pollution levels and to suggest new possible monitoring configurations for this network. Posterior PCA confirmed the misclassification of one site detected with HCA. The authors consider the stepwise approach used in this work to be promising and able to be applied to other air monitoring network studies. [Copyright &y& Elsevier]

The representation of pollen and spores in the fossil record of late Quaternary sedimentary sequences depends on several factors, including the production and dispersion of pollen grains. Thus, the analysis of modern pollen rain contributes to the understanding of these factors and to the knowledge of how vegetation is represented in the fossil pollen spectra. Modern pollen rain from eight vegetation types along an altitudinal gradient from 2300 to 4329 masl in the basin of Mexico are analyzed by using different statistical methods. Pollen spectra from high elevation plant communities > 3800 masl were divided from low altitudes by applying cluster analysis. Based on pollen composition, this study uses DCA to distribute the plant communities in an altitudinal gradient, and probability density functions (PDF) are used to describe the distribution of pollen along the altitudinal gradient. Pollen taxa with low percentages characterize the low altitude sites, with PDFs similar to the parental taxa. Pinus, Poaceae and Asteraceae show wide altitudinal ranges and their PDFs reflect a pattern comparable to the parental taxa, while Quercus, Alnus, Salvia and Salix with narrow altitudinal ranges have PDFs that indicate pollen transport to higher altitude sites. The presence of Mimosa, which present a well defined PDF, can be used as an indicator of paleoenvironmental conditions in the fossil pollen sequences in the basin of Mexico. [ABSTRACT FROM AUTHOR]

Soil organic carbon (SOC) concentration is a soil variable subject to changes. In agricultural soils, the management system is a key factor that influence to these changes. For determine the management system effects on SOC stocks (SOC-S) in olive groves, 114 soil profiles were studied in the Los Pedroches Valley (Mediterranean rangelands - southern Spain) for long-term (20 yr). The management practices were conventional tillage (CT) and organic farming (OF) in four soil types: Cambisols (CM), Regosols (RG), Luvisols (LV) and Leptosols (LP). Soil properties were statistically analyzed by management techniques, soil types and horizons. The principal components analyses identified four factors that explained 65% of the variance. Also, significant differences (p < 0.05) were found between soil types and management techniques. Equally was observed that the management system affected to SOC-S. In addition, the total SOC-S for 20 yr increased in OF with respect to CT by 72% and 66% in CM and LV respectively. The SOC showed significant differences for horizons (p < 0.05) in relation to the management types. The stratification ratio index of SOC was > 2 in all studied soils. These results indicate high soils quality, and that management practices affect to SOC store in the Los Pedroches Valley. [ABSTRACT FROM AUTHOR]

Highlights: [•] SOC and TN are compared for Mediterranean Cambisols under dehesas and olive groves. [•] Land use change to olive groves increased SOC and total N under organic management. [•] SOC and total N decreased in depth for both land uses and management options. [•] The stratification ratios for SOC were generally greater than 2. [Copyright &y& Elsevier]

Abstract: Central Mexico is a complex area with late Quaternary volcanic activity, climatic diversity and a long history of human occupation. Pollen, microcharcoal and magnetic susceptibility analyses of two sedimentary sequences from Lake Zirahuen in western central Mexico spanning the last 17,000years provide evidence of a highly dynamic environment. During the late glacial Pinus forest developed around the lake, indicating cold and dry conditions. During the last deglaciation climatic amelioration was recorded at 13.5ka, driving a strong and rapid change in vegetation composition and increase in lake levels. From the latest Pleistocene to early Holocene a hiatus, probably related to an erosive event, is recognized in the northern sequence. The central sequence spans the entire Holocene and reveals three periods of important ecological changes during the early Holocene. A first episode between 9.5 and 9.0ka with a decrease in pine forest seems to have been associated with summer insolation increases. A second peak of forest change at 8.2ka and was probably associated with the cold oscillation documented in the North Atlantic. A third abrupt change was evident from 7.5 to 7.1ka with an anomalous plant community related to wetter Holocene climates and possible to a volcanic event. An episode of dry conditions was recorded from 4.5 to 4.2ka, which was related to an increase in ENSO activity. Human influence over the landscape was evident from 3.5ka to the present. The Zirahuen records offer a complex history of a landscape characterized by short and long term vegetation changes associated with factors ranging from global climate to local disturbances. [Copyright &y& Elsevier]

Abstract: Olive grove soils in semi-arid Mediterranean areas are very poor in organic matter and are exposed to progressive degradation processes. Therefore, additions of the olive mill by-products as organic amendments can improve soil quality and hence mitigate the negative environmental and agronomic limitations of these soils. A field study was conducted to assess the short-term effects of two oil mill by-products [olive leaves and alperujo (a two-phase olive mill waste)] and determine soil organic carbon (SOC), total nitrogen (TN), the C:N ratio, and their stratification across the soil profile, in an area under Mediterranean conditions. The experimental design consisted on three large plots each spanning a 100m×100m area covered with unirrigated olive trees of the Picual variety less than 30 years old under conventional tillage (CT) in the province of Jaen (southern Spain). One of the plots (CT) was used as control plot and the other two were treated with alperujo (CTa) and olive leaves (CTol), respectively. Soil properties were assessed three years after the by-products were applied. Supplying the soil with the by-products increased C and N stocks. Thus, the SOC stock was 75.4Mgha−1 in CT, 91.5Mgha−1 in CTa and 136.3Mgha−1 in CTol; and the TN stock 12.1, 13.9 and 16.1Mgha−1 in CT, CTa and CTol, respectively. SOC, TN and the C:N ratio in the surface horizon were higher in the treated plots (viz. 18.5gCkg−1, 1.4gNkg−1 and 13.2:1 in CTa, and 84.1gCkg−1, 5.7gNkg−1 and 14.7:1 in CTol) than in the control plot (8.9gCkg−1, 0.9gNkg−1 and 9.8:1, respectively). In addition, application of the by-products improved soil quality (the stratification ratio, SR, for SOC was greater than 2). Oil mill by-products such as olive leaves and alperujo are thus potentially useful as soil amendments since they are effective sources of organic matter and nitrogen, improve soil quality and alleviate the environmental and agronomic limitations of Mediterranean agricultural soils, even those under using CT. In addition, the by-products can be recycled on site. [Copyright &y& Elsevier]

Abstract: The purpose of this paper is to outline a procedure for soil block extraction, which is highly appropriate for clay soils. The method described here is rapid and cheap and has been used successfully by us in clay soils in southern Spain for the last six years. A wooden box is used to shape the soil block in situ and protect it during its transport from the field to the laboratory. Polyurethane foam was selected as the bonding agent, between the wooden framework and the soil block in order to avoid any possible alterations of the soil. This type of foam is used because it is strong, durable and non-toxic. The polyurethane foam is applied to the soil block as a permanent coating. This technique allows us to extract the clay soil solution in the laboratory. [Copyright &y& Elsevier]

Abstract: In Spain, agriculture triggers soil degradation and erosion processes. New strategies have to be developed to reduce soil losses and recover or maintain soil functionality in order to achieve a sustainable agriculture. This experiment was designed to evaluate the effect of two olive mill wastes (olive leaves and “alperujo”) on soil properties and soil erosion in a rain fed olive grove in SE Spain. After three years experiment, oil mill wastes application significantly improved physical and chemical properties of the studied soil with respect to control. The organic matter content, bulk density and porosity were increased, which confirmed the interactions of these properties. Available water capacity increased with olive leaves but decreased when applied “alperujo”. With respect to erosion, after simulated rainfall experiments it was found that the oil mill wastes contributed to increase the roughness and the interception of raindrops, delaying runoff generation and enhancing the infiltration of rainwater. Treatment with oil mill wastes contributed to a reduction in runoff generation and soil losses compared to bare soil, especially when applied olive leaves. [Copyright &y& Elsevier]

Abstract: Potassium is an essential macronutrient for plants; it is characterized by increased photosynthetic activity by ensuring a better utilization of light energy, also acts as a regulator of cell osmotic pressure, decreasing transpiration and helping to maintain cell turgidity. However, the sodium is not an essential element for plants, although it is beneficial to certain crops, in some instances can replace the potassium and osmotic regulation making and turgidity of the cells, this effect is greatest when the supply of potassium is deficient (). Both elements, in periods of aridity, delayed the wilting of plants to maintain cellular osmotic potential and in cold periods, they lower the freezing point of sap (). This is an experiment to study the influence of soil management techniques on the monovalent cations in soil solutions at different depths. The cropping systems studied are conventional tillage, minimum tillage and direct drilling. Conventional tillage releases more Na+ and K+ to the soil solution than the conservative techniques. In the case of Na+, the conventional tillage soil solution has an average concentration of 0.563meq/L compared to 0.303meq/L of minimum tillage and 0.340meq/L of direct drilling. As for the K+, the soil solution concentration of conventional tillage is 0.097meq/L, compared to 0.079meq/L of the solution of minimum tillage and 0.056meq/L of direct drilling. The behavior for the two cations studied is distinct at different depths. The Na+ is more abundant in water samples of soil taken in depth. Therefore, the salinization risk may take place in the subsoil, especially in conventional tillage where the Bw1 horizon values are three times higher than in the Ap horizon, while the K+ is more abundant in the surface horizon. Conventional tillage and minimum tillage techniques, in the Ap horizon have a similar pattern with a K+ concentration average of 0.15meq/L and 0.14meq/L, respectively, resulting in lower values for direct drilling. Studies on clay soils have not been performed previously because of the difficulty presented by these soils when soil solution extracted for analysis. We analyzed the monovalent cations (sodium and potassium) from soil solution; because the soil solution is the immediate source of sodium and potassium for plants. [Copyright &y& Elsevier]

Abstract: Building up a scenario of Late Pleistocene–Holocene environmental change and human–landscape interactions in Central Mexico – one of the key areas for the natural and cultural history of America – requires development of local paleoenvironmental reconstructions. We studied the Tepexpan section at the edge of Texcoco a paleolake, near the mouth of Teotihuacan Valley as a multiproxy record of the environmental dynamics at the shore in the Basin of Mexico throughout the period of human occupation. The section is located in an ecotone affected by intensive and variable geomorphic processes and includes lacustrine, fluvial and volcanic sediments as well as paleosols. Our chronological scale is based on 6 AMS 14C dates from pollen concentrates and paleosol organic matter. The lower segment of the section dominated by the lacustrine sediments yielded pollen spectra; in the upper segment the record is based on the pedogenetic characteristics of paleosols. Different proxies agree in demonstrating the general trend (although some reversals are apparent) of decreasing effective moisture since MIS3: it is reflected first in the increase of herbaceous pollen after 27ka BP, the decrease of lake level, the cessation of lacustrine sedimentation and beginning of marsh soil development at 10ka BP and finally, the shift from hydromorphic to dryland semiarid pedogenesis in the Late Holocene. We assume that this trend was climatically controlled, whereas the deposition of sedimentary layers enriched with tephra are related to the pulses of volcanic activity; the pedosedimentary features associated with the upper soil are human-induced. Comparing the proposed scheme of environmental change with the archaeological record we propose that the initial settlers, Late Paleolithic hunters, could have utilized the wet swampy meadows which expanded on the Basin bottom as the lake level lowered and provided the niche for large herbivores during the Pleistocene–Holocene transition. Development of agriculture and the network of permanent settlements are believed to be linked to the formation of well drained soils. In the methodological perspective the study shows the potential of ecotones as highly dynamic and sensitive systems that may archive valuable paleoecological records. [Copyright &y& Elsevier]

Multiproxy analysis (pollen, diatom, charcoal) on a 6 m core from Lago Verde (Sierra de Los Tuxtlas), shows evidences of environmental changes and human impact on the evergreen rainforest on the tropical lowlands of eastern Mexico during the last ca. 2,800 years. Prehistoric human occupation is recorded since the late Formative throughout the middle Classic (250 b.c.–ca. a.d. 800) by the presence of maize pollen, a low abundance of tropical arboreal taxa and a high abundance of herbaceous pollen and charcoal particles. This occurred under a scenario of very low lake levels from which dry conditions are inferred based on the dominance of aerophilous and periphytic diatom taxa. After ca. a.d. 800 the site was abandoned and forest regeneration started, at the same time higher lake levels, an indication of more humid conditions, were established. In the absence of human disturbance, tropical forest regeneration was rapid (ca. 200 years). Fluctuations in pollen composition during times of low human population at the site are related to climate variability, with the highest tropical forest diversity and lake levels recorded during the Little Ice Age. Modern human impact is also recorded and compared with the prehistoric deforestation event. Comparison with palaeoecological records from Yucatan and the highlands of central Mexico offers a Mesoamerican perspective of climatic variability giving evidence that the late Formative and early to middle Classic demographic expansion occurred under a scenario of climates dryer than present, with the Postclassic characterized by moister conditions. The end of the Classic (ca. a.d. 800–1000) is identified as a period of rapid climate change which marks one of the most important cultural transitions in Mesoamerica. [ABSTRACT FROM AUTHOR]

The article offers information on a study related to the incorporation of sustainable development at the Tecnológico de Monterrey in Mexico. It reports that the study aimed at providing information regarding the activities implemented by the institution in order to infuse sustainable development (SD) into the academic components. It discusses the experience of institution regarding SD implementation in the academic area. It informs that the inclusion of SD concepts into courses and curricula requires a support by several stakeholders within the institution.

Purpose - This paper sets out to discuss the commonalities that can be found in learning outcomes (LOs) for education for sustainable development in the context of the Tbilisi and Barcelona declarations. The commonalities include systemic or holistic thinking, the integration of different perspectives, skills such as critical thinking, change agent abilities and communication, and finally different attitudes and values. Design/methodology/approach - An analysis of LOs that are proposed in the Tbilisi and Barcelona declarations is conducted, showing specific issues for the commonalities presented. Examples of LOs from Instituto Tecnológico y de Estudios Superiores de Monterrey (ITESM) in Mexico, as well as various associations from the USA is shown. A brief discussion is done on the means to achieve these LOs and learning evaluation. Findings - In the example sets of LOs shown, the commonalities presented in the paper's first section appear in the LOs proposed by the institutions. Based on current knowledge and perception, sustainability is properly addressed in the examples. Practical implications - The paper can be used to foster a wider discussion and analysis of LOs for sustainability education, also further work on teachers' capacity building for sustainability, as well as the assessment needed for future professionals in higher education institutions. Originality/value - The paper presents the onset of discussing and comparing commonalities among higher education institutions regarding sustainability LOs. [ABSTRACT FROM AUTHOR]

Purpose - The purpose of this paper is to present information about a team-teaching course on sustainable development (SD) for educators in an institution of higher education, Monterrey Campus of ITESM in México. Design/methodology/approach - Four faculty members were invited to work together with the Sustainable Campus Programme coordinator in the process of developing the "Educate-the-Educator's" SD course. The course was structured using lectures, readings, class role play activities, homework, and general discussion. Additionally, a workshop-format was woven throughout the course; its function was to help the educators incorporate SD issues within their own courses. Findings - It was found that a multi-disciplinarily developed and delivered course is an effective vehicle for educating educators on SD. Documentation of some facets of the learning process further helped the "students" and the course leaders to better understand the whole learning process. Originality/value - The paper's value rests on the interconnected structure, showing resonance with the triple bottom line, as well as many other dimensions linked with sustainable development. This structure increased the course participants' comprehension of sustainability. Furthermore, the use of concept maps and digraph theory to evaluate "faculty participants'" comprehension of the interconnections and dimensions of SD proved to be a successful innovation. [ABSTRACT FROM AUTHOR]