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Cytogenetic evidence indicates that Zea, which comprises maize (Z. mays ssp. mays) and its wild relatives, is an allopolyploid genus. Our research group has carried out numerous cytogenetic studies on Zea species, mainly focused on native Argentinian and Bolivian maize landraces. We found a wide inter- and intraspecific genome size variation in the genus, with mean 2C-values ranging between 4.20 and 11.36 pg. For the maize landraces studied here, it varied between 4.20 and 6.75 pg. The objectives of this work are to analyze the causes of genome size variation and to discuss their adaptive value in Zea. This variation is mainly attributed to differences in the heterochromatin located in the knobs and to the amount of interspersed DNA from retrotransposons. Polymorphisms in presence or absence of B-chromosomes (Bs) and the population frequency of Bs are also a source of genome size variation, with doses ranging between one and eight in the landraces analyzed here. Correlation analysis revealed that the percentage of heterochromatin is positively correlated with genome size. In addition, populations cultivated at higher altitudes, which are known to be precocious, have smaller genome sizes than do those growing at lower altitudes. This information, together with the positive correlation observed between the length of the vegetative cycle and the percentage of heterochromatin, led us to propose that it has an adaptive role. On the other hand, the negative relationship found between Bs and heterochromatic knobs allowed us to propose the existence of an intragenomic conflict between these elements. We hypothesize that an optimal nucleotype may have resulted from such intranuclear conflict, where genome adjustments led to a suitable length of the vegetative cycle for maize landraces growing across altitudinal clines. Key words: B chromosomes, heterochromatin, intragenomic conflict, knobs, maize landraces

Funding Acknowledgements Type of funding sources: None. Background In case of persistent atrial fibrillation (AF), atrial substrate assumes a dominant role in sustaining the arrhythmia. Recent studies prove that low voltage areas (LVA, Voltage Amplitude < 0,5 mV) represent an additional target for ablation of AF patients. Purpose The purpose of this study is to analyse whether structural atrial conduction abnormalities (i.e., pivot sites and slow conduction corridors) may occur outside low voltage areas. Methods The study is based on the retrospective analysis of 31 consecutive maps of patients undergoing AF ablation (16 paroxysmal and 15 persistent cases). The clinical procedures have been performed with the support of a mapping system. Sinus rhythm activation maps and bipolar maps used for this analysis have been created with a multipolar mapping catheter. Map points were only acquired when the electrode was in contact with the endocardial tissue to avoid misleading voltage amplitude information. Slow conduction corridors and pivot sites have been analysed. At these sites, EGMs characterization included voltage amplitude (mV), signal duration (ms) and fractionation. Results The average value of EGMs amplitude reported at pivot sites and slow conduction zones, respectively, amounted to 2,08 ± 0,63 mV and 2,1 ± 0,66 mV in paroxysmal cases. In persistent cases, there were slight decreased values to 1,95 ± 0,93 mV and 1,89 ± 0,89 mV. Characterization at pivot sites documented a mean duration value of 45,4 ± 4,64 ms and 49,93 ± 5,51 ms in paroxysmal and persistent patients, respectively, while in slow conduction zones 41,53 ± 7,94 ms and 49,04 ± 6,41 ms have been reported. As for fractionation, more than five deflections per signal have been identified in all abnormal conduction areas. Conclusion Our study proves that functional electrophysiological phenomena can occur outside low voltage areas, even in persistent cases. According to this analysis, not all LVA represent the correct target for catheter ablation, encouraging the development of further methods for investigation of atrial substrate.

Funding Acknowledgements Type of funding sources: None. Background Atrial fibrillation (AF) progresses with a cascade of combined structural, functional, and systemic dysfunctions. Electro-anatomical maps are employed to investigate pro-arrhythmic areas, characterized by abnormal electrical properties. However, single rhythm maps provide only a partial reconstruction: rhythm and wavefront directionality might mask some of these areas. Purpose To demonstrate that the combined quantitative analysis of different rhythm maps (i.e., parallel sinus rhythm and paced maps) could allow consistent identification of structural and functional defects sustaining AF. Methods Thirty AF clinical procedures have been performed with mapping system support. In particular, a sinus rhythm activation map and a paced map have been created with a multipolar catheter exploiting the parallel mapping feature by setting an extra beat (pacing interval = ERP + 40 ms) every three sinus beats. Areas of abnormal conduction have been identified and a comparison of electrophysiological biomarkers (EGMs voltage and fractionation) among the two rhythms has been performed. Results This comparative analysis allowed us to identify both structural and functional electrophysiological phenomena. Specifically, we distinguished: (i) abnormal conduction zones confirmed in both maps, both characterized by signal fractionation and a lower voltage (0,56 ± 0,18 mV) with respect to healthy atrial tissue (2,40 ± 0,41 mV), and (ii) abnormal conduction zones visible in only one of the two maps. In the latter, we distinguished whether the absence of the phenomena was due to wavefront orthogonality to the diseased area (revealed in paced rhythm thanks to a change in wavefront direction) or due to the presence of a functional phenomenon induced by the pacing. In the first group signal fractionation has been detected in both rhythms and a lower voltage has been found (1,79 ± 1,1 mV) with respect to normal conduction zones (3,26 ± 0,98 mV), while in functional cases EGMs fractionation has been identified only in paced maps and no significant difference has been observed in terms of voltage. Conclusion Double rhythm mapping provides a more robust characterization of atrial abnormal conduction phenomena. In fact, it allowed the distinction of true structural dysfunctions from dynamic (functional) ones thanks to the different wavefront directionality and rhythm. Moreover, the structural defects have been confirmed by EGMs analysis, which revealed both low voltage amplitude and high fractionation, characteristics that have not been reported in functional cases.

Funding Acknowledgements Type of funding sources: None. Background The ongoing challenge is to generate meaningful data during electrophysiological (EP) studies, integrating the knowledge on atrial fibrillation (AF) progression gained by the EP community in the latest years. At the present time there is a lack of EP protocols: most of the centers perform electroanatomical (EA) ablation to isolate pulmonary veins or, in persistent AF forms, some centers propose the performance of additional lines for atrial compartmentalization. However, none of these approaches take in consideration neither the wavefront propagation nor the analysis of functional phenomena. Purpose To investigate whether zones of delayed conduction (slow conduction, SC) or functional propagation (pivot sites, PS) may play a role in terms of maintenance of paroxysmal (PAF) and persistent (PsAF) AF. Methods Twenty-seven consecutive patients with PAF (14 patients) and PsAF (13 patients) have been enrolled in this study. For each patient, a sinus rhythm activation map and a paced map have been created with a multipolar catheter exploiting the parallel mapping feature. According to these activation maps, we analyzed the wavefront propagation. Abnormal conduction was defined as a delimited zone in which the propagation became suddenly slower (90°, pivot sites). At each of these sites, EGMs were collected and analysed in terms of amplitude (mV), location and fractionation. Results In sinus rhythm maps, a total number of 65 pivot sites and slow conduction corridors was identified. In the PAF group 22 PS and SC were found (1,6/pt), whereas those included in the PsAF one showed a significantly higher number: 43 (3,3/pt). The bipolar voltage value reported at abnormal conduction areas amounted to 1,95 ± 0,93 mV and 1,78 ± 0,54 mV for PAF and PsAF patients, respectively, showing a lower value with respect to healthy tissue areas (2,94 ± 4,81 mV). More than four deflections per signal were identified in 57/65 PS and SC zones. In PsAF cases, these areas were mainly found on the posterior wall. A concordance with esophagus location occurred in the 89%. In paced maps, instead, we documented an average value of 38 PS and SC zones (1,5/pt), of which 27 in persistent patients. As for bipolar values, a lower voltage value was reported in PS and SC zones (1,91 ± 0,69 mV for PAF and 1,52 ± 0,36 mV for PsAF) with respect to normal conductive tissue. Fractionation of EGMs was confirmed in almost all cases. Conclusion The main findings of this analysis are: (i) in PsAF patients the number of pivot sites is higher with respect to PAF cases; (ii) In PsAF patients, abnormal conduction phenomena are predominantly localized on the posterior wall, with a strong correlation with esophagus location; (iii) slow conduction zones and pivot sites are characterized by lower voltage amplitude and higher fractionation with respect to normal conduction areas.

Background Pulmonary veins isolation (PVI) represents the main strategy for paroxysmal atrial fibrillation (AF) treatment. Due to the poor clinical outcomes of PVI in case of non–paroxysmal AF, significant efforts have been made to develop new ablative strategies to modify the atrial substrate. Up to now, in order to characterise atrial substrate, only bipolar voltage maps have been used and impedance mapping has never been evaluated. Purpose Our aim is to demonstrate the potential correspondence among atrial wall thickness, bipolar voltage and impedance. Atrial impedance mapping could represent an additional tool for atrial substrate characterization, providing further information on tissue conductive properties and confirming bipolar substrate analysis. Methods The study includes the retrospective analysis of 60 electro–anatomical (EA) maps of patients with paroxysmal (40 patients) and persistent (20 patients) AF admitted to our institution for treatment. The clinical procedures have been performed with the support of CARTO3 mapping system. Map points have been collected with Navistar RMT Thermocool ablation catheter in order to enable the evaluation of atrial impedance values. To perform the correspondence analysis between the voltage map and impedance map, the atrial endocardial surface has been divided in six sections. Before ablation, for all patients a computed tomography has been performed in order to evaluate atrial endocardial thickness. Parameters of interest that have been evaluated in this study are EGMs voltage amplitude (mV) and fractionation (> five deflections per signal) and the corresponding impedance value (Ohm) at the considered acquisition point. Results In all PAF cases no voltages lower than 0.5 mV have been reported. The corresponding impedance values ranged from 140.6 to 169.9 Ohm, with an average value of 151.5 ± 5.4 Ohm. In PsAF cases, instead, voltage values inferior to 0.05 mV have been reported in the posterior wall, anterior wall and roof in 19/20 patients. In these low voltage areas, long duration fractionated signals have been reported and the average impedance value dropped to 129.1 ± 3.8 Ohm, ranging from 110.2 Ohm to 139.6 Ohm. Conclusion Our study supports the association between left atrial thickness, voltage amplitude and impedance values. This allows the correct substrate evaluation in case of uncertain bipolar values thanks to additional information provided by impedance mapping.

Background Several clinical data in humans demonstrate that atrial fibrillation (AF) dominant frequencies and rotors are mostly localized on the posterior wall (PW), but the correlation among these phenomena and abnormal conduction properties during sinus (SR) and paced rhythm (PR) has never been analyzed. Aims. To provide a characterization of the left atrial PW in patients affected by persistent AF. In particular, the purpose is to describe the electrophysiological properties in terms of rotational and focal activities during AF, propagation uniformity during SR and functional sites definition during PR. Methods Six patients from two EP centers have been selected for this analysis. The clinical procedures have been performed with CARTO3 mapping system. All EGMs have been collected with Pentaray and Octaray catheters. For each patient, the module CARTOFINDER has been used during AF to identify areas with shorter and longer cycle length (site of conduction jump), rotational and focal activities; at least 15 areas have been collected in the PW. SR and PR map were performed after electrical cardioversion to exploit the functional phenomena. The paced map has been created by setting an extra beat from the coronary sinus every three sinus beats (pacing interval=local effective refractory period +40ms). Rotational and focal activities during AF have been identified and associated with signals collected during SR and PR. EGMs have been characterized in terms of voltage amplitude (mV), signal duration (ms) and fractionation. Results Abnormal areas of conduction recorded during AF were 33; at least one site of conduction jump was found in every patient, in most of the cases (77%, 10 out of 13) it was localized on the PW. 10 areas of focal activities have been found of which 7 (70%) were localized on the PW. Rotational activity has been found in 2 patients (in one on the PW). During SR and paced rhythm, at sites of interest, we found lower voltages (SR 1.9 ± 1,3mV, PR 1,7 ± 1,15mV), signal fragmentation and longer signal duration (SR 52,7 ± 8,85ms, PR 51,3 ± 11,04ms) compared to healthy tissue. Conclusion There is a strong correlation between sites of interest during AF and signal abnormalities recorded during SR and PR. This research work may pave the way to the study of abnormal conduction sites during SR which represent a relevant element for AF maintenance, providing a further step towards substrate characterization in patients affected by AF.

Background Atrial fibrillation (AF) progresses with a cascade of combined structural, functional, and systemic dysfunctions. Electro–anatomical maps are employed to investigate pro–arrhythmic areas. However, single rhythm maps provide only a partial reconstruction: rhythm and wavefront directionality might mask some of these areas. Purpose. To demonstrate that the combined quantitative analysis of different rhythm maps (i.e., parallel sinus rhythm and paced maps) could allow consistent identification of structural and functional defects sustaining AF. Methods Thirty AF clinical procedures have been performed with mapping system support. In particular, a sinus rhythm activation map and a paced map have been created with a multipolar catheter by setting an extra beat every three sinus beats. Areas of abnormal conduction have been identified and a comparison of electrophysiological biomarkers (EGMs voltage and fractionation) among the two rhythms has been performed. Results This comparative analysis allowed us to identify both structural and functional electrophysiological phenomena. Specifically, we distinguished: (i) abnormal conduction zones confirmed in both maps, both characterized by signal fractionation and a lower voltage (0,56 ± 0,18 mV) with respect to healthy atrial tissue (2,40 ± 0,41 mV), and (ii) abnormal conduction zones visible in only one of the two maps. In the latter, we distinguished whether the absence of the phenomena was due to wavefront orthogonality to the diseased area (revealed thanks to a change in wavefront direction) or due to the presence of a functional phenomenon induced by the pacing. In the first group signal fractionation has been detected in both rhythms and a lower voltage has been found (1,79 ± 1,1 mV) with respect to normal conduction zones (3,26 ± 0,98 mV), while in functional cases EGMs fractionation has been identified only in paced maps and no significant difference has been observed in terms of voltage. Conclusion Double rhythm mapping provides a more robust characterization of atrial abnormal conduction phenomena which better represent AF electrical substrate. It allows the distinction of true structural dysfunctions from dynamic ones thanks to the different wavefront directionality and paced rhythm. Moreover, the structural defects have been confirmed by EGMs analysis, which revealed both low voltage amplitude and high fractionation, characteristics that have not been reported in functional cases.

Background In case of persistent atrial fibrillation (AF), atrial substrate assumes a dominant role in sustaining the arrhythmia. Recent studies prove that low voltage areas (LVA, Voltage Amplitude < 0,5 mV) represent an additional target for ablation of AF patients. Purpose. The purpose of this study is to analyse whether structural atrial conduction abnormalities (i.e., pivot sites and slow conduction corridors) may occur outside low voltage areas. Methods The study is based on the retrospective analysis of 31 consecutive maps of patients undergoing AF ablation (16 paroxysmal and 15 persistent cases). The clinical procedures have been performed with the support of a mapping system. Sinus rhythm activation maps and bipolar maps used for this analysis have been created with a multipolar mapping catheter. Map points were only acquired when the electrode was in contact with the endocardial tissue to avoid misleading voltage amplitude information. Slow conduction corridors and pivot sites have been analysed. At these sites, EGMs characterization included voltage amplitude (mV), signal duration (ms) and fractionation. Results The average value of EGMs amplitude reported at pivot sites and slow conduction zones, respectively, amounted to 2,08 ± 0,63 mV and 2,1 ± 0,66 mV in paroxysmal cases. In persistent cases, there were slight decreased values to 1,95 ± 0,93 mV and 1,89 ± 0,89 mV. Characterization at pivot sites documented a mean duration value of 45,4 ± 4,64 ms and 49,93 ± 5,51 ms in paroxysmal and persistent patients, respectively, while in slow conduction zones 41,53 ± 7,94 ms and 49,04 ± 6,41 ms have been reported. As for fractionation, more than five deflections per signal have been identified in all abnormal conduction areas. Conclusion Our study proves that functional electrophysiological phenomena can occur outside low voltage areas, even in persistent cases. According to this analysis, not all LVA represent the correct target for catheter ablation, encouraging the development of further methods for investigation of atrial substrate.

espanolEn el marco del enfoque cognitivo prototipico, que parte del presupuesto de que la sintaxis esta motivada por la semantica y la pragmatica, el presente trabajo sostiene la hipotesis de que en la oposicion entre preterito perfecto simple (pps) y preterito imperfecto (pi), cada tiempo verbal tiene un conjunto de atributos semanticos que lo definen, dependiendo del contexto de uso y del objetivo comunicativo de los hablantes. Estos atributos no solo se relacionan con el aspecto verbal, sino tambien con la funcion discursiva. Para comprobar la hipotesis, analizamos cuantitativa y cualitativamente los usos de pps y pi en un corpus de textos narrativos. EnglishIn accordance with the prototypical-cognitive approach, which postulates that semantics and pragmatics are motivated by syntax, the present study formulates the hypothesis that in the opposition between the Spanish preterit and the imperfect, each verb tense has a cluster of semantic attributes which define them, depending on the context in which they occur and on the speaker’s communicative purpose. These attributes are related not only to the grammatical aspect of the verb but to the discursive function. In order to confirm this hypothesis, the uses of Spanish preterit and imperfect have been analysed qualitatively and quantitatively in a corpus of narrative texts.

Soil classification is based on both the properties of the soil material and the pedogenetic pathways responsible for those properties. Because soil properties are linked to soil function and potential, information on soil classification has formed the basis for empirical interpretations of mapping units in terms of limitations or suitabilities for a wide range of land uses. In this way, a soil type acts as an accessible "carrier of information" presenting "the story of.". Though valuable for broad land-use assessments, these empirical interpretations of soil functionality are inadequate to answer modern interdisciplinary questions focused on sustainable development. Four case studies are presented showing various quantitative approaches focusing on soil functions contributing to ecosystem services in line with the United Nations Sustainable Development Goals (SDGs) and the European Green Deal, demonstrating that: (i) the use of soil surveys and associated databases feeding soil-water-atmosphere-plant simulation models can contribute to defining soil functions and ecosystem services; (ii) hydropedological characterization of soil types can allow a strong reduction in the number of landscape units to be considered, improving practical applicability; (iii) pedotransfer functions can successfully link soil data to modeling parameters; (iv) functionality requires expression of soil management effects on properties of a given soil type, to be expressed by phenoforms; (v) only models can be applied to explore important future effects of climate change by running IPCC scenarios; and (vi) the most effective level of soil classification--acting as carriers of information when defining soil functionality--will differ depending on the spatial scale being considered, whether local, regional or higher.

La Commissione Europea (CE) ha inserito ad oggi 36 taxa esotici vegetali nella lista delle specie esotiche invasive di rilevanza unionale ai sensi del Regolamento (UE) n. 1143/2014 del Parlamento Europeo e del Consiglio, recante disposizioni volte a prevenire e gestire l’introduzione e la diffusione delle specie esotiche invasive. La lista delle specie di rilevanza unionale viene periodicamente aggiornata e include quelle specie che rappresentano una grave minaccia per la biodiversità, ma anche per la salute dei cittadini e le attività economiche nei territori dell’Unione Europea e che necessitano di una gestione concertata a livello comunitario. La CE vigila sullo stato di ogni taxon grazie anche a periodiche rendicontazioni da parte dei paesi dell'Unione. In vista di tali report, tra il 2020 e il 2021 è stata definita e integrata la distribuzione di queste specie in Italia.

While the disparities for minority patients with cancer have been well established, few studies have illustrated disparities in cancer outcomes while controlling for potential confounding factors. The current study was designed to address these confounding variables and how they influence the treatment and survival time for patients with rectal cancer.Using the Surveillance, Epidemiology, and End Results database, black and Hispanic patients were compared with white patients with rectal cancer for the rates of chemotherapy, radiation, and surgery in addition to survival time after diagnosis. Following this analysis, confounding variables were controlled for and analysis was repeated with groups of comparable demographic variables.Before controlling for confounding variables, there were significant differences in treatment and survival for both Hispanic and black patients compared with white. Following matching, black patients continued to have lower rates of treatment and shorter survival times.These differences in treatment methods and survival outcomes for minorities, particularly black patients, highlight the need for more advocacy and focus on these underrepresented populations with rectal cancer.

The concept of health has been widely used to refer to soils, crops or agroecosystems. It resembles the idea of wholeness or general well-being, which is interesting to integrate different discipli...

This article belongs to the Special Issue The Application of Models for Weed Management in Cropping Systems., In weed science and management, models are important and can be used to better understand what has occurred in management scenarios, to predict what will happen and to evaluate the outcomes of control methods. To-date, perspectives on and the understanding of weed models have been disjointed, especially in terms of how they have been applied to advance weed science and management. This paper presents a general overview of the nature and application of a full range of simulation models on the ecology, biology, and management of arable weeds, and how they have been used to provide insights and directions for decision making when long-term weed population trajectories are impractical to be determined using field experimentation. While research on weed biology and ecology has gained momentum over the past four decades, especially for species with high risk for herbicide resistance evolution, knowledge gaps still exist for several life cycle parameters for many agriculturally important weed species. More research efforts should be invested in filling these knowledge gaps, which will lead to better models and ultimately better inform weed management decision making., Muthukumar V. Bagavathiannan’s research program is supported by state and federal funds appropriated to Texas A&M AgriLife Research. Gayle J. Somerville was supported by the UKRI project of evaluating people-environment trade-offs through low-tech intensification of livestock management in communal grazing systems in South Africa (BB/S014683/1) whilst working at Rothamsted. Brian J. Schutte is supported by state and federal funds appropriated to the New Mexico Agricultural Experiment Station. JLG-A was funded by FEDER (European Regional Development Funds) and the Spanish Ministry of Economy and Competitiveness grants (projects AGL2015-64130-R). Guillermo R. Chantre received funding from Agencia Nacional de Promoción Científica y Tecnológica MINCyT (PICT-2016-1575) and Universidad Nacional del Sur of Argentina (PGI 24/A225).

Mitochondria have emerged as important determinants in cancer progression and malignancy. However, the role of mitochondrial membranes in cancer onset and progression has not been thoroughly investigated. This study compares the structural and functional properties of mitochondrial membranes in prostate and colon cancer cells in comparison to normal mitochondria, and possible therapeutic implications of these membrane changes. Specifically, isolation of cell mitochondria and preparation of inverted sub-mitochondrial particles (SMPs) illuminated significant cancer-induced modulations of membrane lipid compositions, fluidity, and activity of cytochrome c oxidase, one of the key mitochondrial enzymes. The experimental data further show that cancer-associated membrane transformations may account for mitochondria targeting by betulinic acid and resveratrol, known anti-cancer molecules. Overall, this study probes the relationship between cancer and mitochondrial membrane transformations, underlying a potential therapeutic significance for mitochondrial membrane targeting in cancer.

Women living with HIV (WLHIV) are at increased risk for human papillomavirus (HPV)-associated anal cancer. Given the “field effect” of HPV pathogenesis, some recommend that anal cancer screening should be limited to WLHIV with prior genital disease. This study aimed to characterize the relationship between anal and genital disease in WLHIV in order to better inform anal cancer screening guidelines. We retrospectively studied 153 WLHIV with biopsy-proven anal high-grade squamous intraepithelial lesions (AHSIL) and long-term evaluable cervical/vaginal/vulvar histopathology. Based on the absence or presence of genital HSIL, subjects were categorized as having isolated AHSIL or multicentric HSIL. Demographics, HIV parameters and cervical/anal HPV status were recorded. Chi-square test was used for bivariate analyses. Of 153 WLHIV with AHSIL, 110 (72%) had isolated AHSIL, while 43 (28%) had multicentric HSIL (28 cervical, 16 vulvar, and 8 vaginal HSIL). The median genital surveillance was 8 years (range 1–27). Cervical HPV16/18 infection was associated with multicentric disease (P = 0.001). Overall, 53% of multicentric cases presented genital HSIL preceding AHSIL with median interval 13 years (range 2–23). Paired anal and cervical high-risk HPV results were available for 60 women within 12 months of AHSIL diagnosis: 30 (50%) had anal infection alone, while 30 (50%) had anal/cervical coinfection by 16/18 (15%), non-16/18 (13%), or different types (22%). In conclusion, WLHIV frequently develop AHSILs without pre-existing genital disease or after long latency following a genital HSIL diagnosis. Our findings support anal cancer screening for WLHIV irrespective of prior genital disease.

espanolEn el presente trabajo, se exponen los resultados de la aplicacion de una secuencia didactica en cursos de primer ano de secundaria de adultos y adultas, pertenecientes a diferentes escuelas de la ciudad de Buenos Aires. Las actividades fueron confeccionadas desde la perspectiva del Enfoque Cognitivo Prototipico (ECP) (Langacker, 1987, 1991; Lakoff, 1987), que sostiene que la gramatica es un sistema de tendencias que refleja la concepcion del mundo de una sociedad. Partimos de la hipotesis de que el enfoque discursivo que plantea el ECP supera las limitaciones que implica operar en un nivel oracional, y, por lo tanto, permite a los y las estudiantes una mejor comprension de las categorias gramaticales que en los casos en los que se utilizan formas descontextualizadas. En el analisis de las secuencias, concluimos que las actividades planteadas desde un enfoque discursivo contribuyeron a mejorar la comprension del tema gramatical y la interpretacion del texto. euskaraLan honetan, Buenos Aireseko hainbat eskolatako helduen bigarren hezkun-tzako lehen urteko ikastaroetan sekuentzia di-daktiko bat aplikatzearen emaitzak azaltzen dira. Jarduerak Ikuspegi Kognitibo Prototipikoaren (ECP) ikuspegitik egin ziren (Langacker, 1987, 1991; Lakoff, 1987); horren arabera, Gramatika gizarte baten mundu-ikuskera islatzen duen joera-sistema da. Abiapuntuko hipotesia da ECPk planteatzen duen diskurtso-ikuspegiak perpaus-mailan jarduteak dakartzan mugak gainditzen dituela, eta, beraz, ikasleei aukera ematen die gramatika-kategoriak hobeto uler-tzeko, testuingurutik kanpoko formak erabiltzen diren kasuetan baino. Sekuentziak aztertzean, ondorioztatu genuen diskurtsoaren ikuspegitik planteatutako jarduerek gramatika-gaia ulertzen eta testua interpretatzen lagundu zutela. EnglishThis paper shows the results of ap-plying a didactic sequence in the first year of adults’ secondary schools in Buenos Aires city. The activities involved were crafted using the perspective of Cognitive-Prototypical Approach (CPA) (Langacker, 1987, 1991; Lakoff, 1987), which states Grammar is a system of tenden-cies that reflects a certain society’s worldview. We start from the hypothesis that the discur-sive approach offered by the CPA overcomes the limitations of operating at sentence level, and therefore allows students a better un-derstanding of grammar categories than the one reached through out-of-context methods. Through the sequence analysis, we conclude that activities set from a discursive approach contributed to enhance the understanding of the grammar topic and the text interpretation

Invasive alien plants are a major threat to biodiversity and they contribute to the unfavourable conservation status of habitats of interest to the European Community. In order to favour implementation of European Union Regulation no. 1143/2014 on invasive alien species, the Italian Society of Vegetation Science carried out a large survey led by a task force of 49 contributors with expertise in vegetation across all the Italian administrative regions. The survey summed up the knowledge on impact mechanisms of invasive alien plants in Italy and their outcomes on plant communities and the EU habitats of Community Interest, in accordance with Directive no. 92/43/EEC. The survey covered 241 alien plant species reported as having deleterious ecological impacts. The data collected illustrate the current state of the art, highlight the main gaps in knowledge, and suggest topics to be further investigated. In particular, the survey underlined competition as being the main mechanism of ecological impact on plant communities and Natura 2000 habitats. Of the 241 species, only Ailanthus altissima was found to exert an ecological impact on plant communities and Natura 2000 habitats in all Italian regions; while a further 20 species impact up to ten out of the 20 Italian administrative regions. Our data indicate that 84 out of 132 Natura 2000 Habitats (64%) are subjected to some degree of impact by invasive alien plants. Freshwater habitats and natural and semi-natural grassland formations were impacted by the highest number of alien species, followed by coastal sand dunes and inland dunes, and forests. Although not exhaustive, this research is the first example of nationwide evaluation of the ecological impacts of invasive alien plants on plant communities and Natura 2000 Habitats.

The concept of functional groups (set of species having similar physiological, ecological or life-history traits) has been largely used for plants, microorganisms, nematodes or insects in agroecosystems. However, this concept has been rarely applied to describe assemblages of plant pathogens. Yet, classification systems in plant pathology resemble this functional approach, as they address different disease processes or life history traits. In this review, we discuss advantages and drawbacks of current classification systems in relation to their application to the ecological management of crop diseases. Then, we propose to reorganize one of the classical plant-pathogen systems in a dichotomous key of functional groups obtained by combining two life-history traits: dispersal and survival strategies. The six functional groups proposed here are soil inhabitants; soil survivors; debris-seed-borne; air-borne; seed-borne, and vector-borne pathogens. We applied these groups to characterize pathogens of two major crops, wheat and tomato, grown in temperate climate regions. Our contribution intends to provide a comprehensive conceptual framework for the design of crop disease management strategies based on ecological principles, as well as to facilitate the interpretation of the occurrence of epidemics in response to the agricultural practices applied in real-world agroecosystems.

Diverticular colitis, also known as segmental colitis associated with diverticulosis, is a colonic inflammatory disorder on the spectrum of inflammatory bowel disease (IBD). The disease consists of macroscopic and microscopic inflammation affecting inter-diverticular mucosa, sparing peri-diverticular mucosa, with inflammation confined to the descending and sigmoid colon. The disease likely arises from the altered immune response of an individual, genetically susceptible to the IBD spectrum of diseases. Patients with segmental colitis associated with diverticulosis (SCAD) are typically older, and likely represent a subgroup of IBD—susceptible patients who lacked an environmental trigger until that point in their life. Most patients remain in remission with initial treatments of mesalamine or topical steroids, and maintenance mesalamine afterwards. Only the most severe form of the disease necessitates immunomodulatory therapy and the consideration of surgery.

IntroductionGynecologic oncology patients represent a distinct patient population with a variety of surgical risks. The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database provides an opportunity to analyze large cohorts of patients over extended periods with high accuracy. Our goal was to develop a postoperative risk assessment calculator capable of providing a standardized, objective means of preoperatively identifying high-risk patients in the gynecologic oncology population.MethodsWe queried the ACS NSQIP database for gynecologic oncology patients from 2005 to 2013. Multivariate logistic regression was performed to generate predictive models specific for 30-day postoperative mortality and major morbidity.ResultsThere were 12,831 patients with a primary gynecologic malignancy identified: 7847 uterine, 3366 adnexal, 1051 cervical, and 567 perineum cancers. In this cohort, 125 (0.97%) patients died, and 784 (6.11%) major morbidity events were recorded within 30 days of their surgery. For 30-day mortality, the mean calculated predictive probability was 0.128 (SD, 0.219) compared with 0.009 (SD, 0.027) in patients alive 30 days postoperatively (P< 0.0001). The mean predictive probability of major morbidity was 0.097 (SD, 0.095) compared with 0.059 (SD, 0.043) in patients who did not experience major morbidity 30 days postoperatively (P< 0.0001).ConclusionsUsing NSQIP data, these predictive models will help to determine patients at risk for 30-day mortality and major morbidity. Further clinical validation of these models is required.

The semiarid Espinal in central Argentina, being recently transformed from natural semiarid grasslands into agriculture, represents an interesting scenario to understand the early stages of weed community assembly and its relationship with crop identity and management. Our aim was to characterize the weed communities in corn (Zea mays L.) and soybean [Glycine max (L.) Merr.], the main crops of the Espinal region, under the dominant rainfed conditions. Weed surveys were carried out in 53 fields, and farmers were interviewed to collect information about crop management. Floristic composition was compared within and between crops by calculating the additive partition of the abundance-based Bray-Curtis dissimilarity. We compared the frequency and mean cover of functional groups between crops through generalized linear models. Finally, canonical correspondence analysis was carried out to analyze the associations between floristic composition and agronomic variables. Mean alpha and gamma diversity was greater in corn (10.0 and 80 species, respectively) than in soybean (7.6 and 46 species, respectively). Furthermore, species composition of weed communities was more similar among soybean fields than among either cornfields or fields of both crops. Hence, floristic differences between crops are potentially the result of different microenvironmental heterogeneity above- and belowground, with corn likely to be more permissive to weed establishment compared with soybean. The higher frequency of annual, dicotyledonous, and native species, and the high proportion of rare species, mostly native, suggest a strong legacy of the original vegetation that thrived in these recently cultivated systems. The functional composition was also affected by agronomic management, with sulfur, nitrogen, and grass herbicide application being the most important factors related to the floristic composition of weed communities. This early description can be used as a starting point for studies concerning trajectories, mechanisms, and processes of weed communities related to environment and management. Fil: Rauber, Ruth Bibiana. Instituto Nacional de Tecnología Agropecuaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Demaría, Manuel R.. Instituto Nacional de Tecnología Agropecuaria; Argentina Fil: Jobbagy Gampel, Esteban Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina Fil: Arroyo, Daniel N.. Instituto Nacional de Tecnología Agropecuaria; Argentina Fil: Poggio, Santiago Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina

Agricultural intensification, besides increasing land productivity, also affects weed communities. We studied weed shifts in cropping sequences differing in the identity and number of crops grown. We also evaluated whether dissimilar weed communities in different cropping systems converge towards more similar communities, when the same sequence is cropped during 2 years. In three locations in the Rolling Pampa, Argentina, field experiments were conducted including five cropping systems in the first year (winter cereal/soyabean, field pea/soyabean, and field pea/maize double crops, and maize and soyabean as single crops), while the same sequence was grown in the following 2 years (wheat/soyabean double crop and maize). Changes in weed community composition and structure were analysed through multivariate analyses and frequency–species ranking plots. Weed communities differed first among sites, while weed shifts within each site were mainly associated with growing season and crop type. Differences among crop sequences were higher in the first year, mostly related to specific crop grown, rather than to the number of crops in the sequences. Differences were reduced when the same sequence was grown during two consecutive seasons. Frequency of highly common weeds was negatively associated with the number of days with high crop cover. Our findings contribute to understand weed shifts in consecutive growing seasons, which may help readapting crop sequences to reduce the occurrence of abundant weed species. Fil: Andrade, José Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía; Argentina Fil: Satorre, Emilio Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía; Argentina. Asociación Argentina de Consorcios Regionales de Experimentación Agrícola; Argentina Fil: Ermácora, C. M.. Asociación Argentina de Consorcios Regionales de Experimentación Agrícola; Argentina Fil: Poggio, Santiago Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía; Argentina

Background Timing of surgery has been shown to affect outcomes in many forms of cancer, but definitive national data do not exist to determine the effect of time to surgery on survival in colon cancer. Objective This study aimed to determine whether a delay in definitive surgery in colon cancer significantly affects survival. Data sources A retrospective cohort study using 2 independent population-based databases, The Surveillance, Epidemiology, and End Results Medicare-linked database and the National Cancer Database, was performed. Study selection All patients had American Joint Committee on Cancer stage 1 through 3 colon cancer. Patients were more than 18 years of age in the National Cancer Database cohort and older than 66 years of age in the Medicare cohort. Patients had a minimum of 3 years of follow-up. Main outcome measures The main outcome was overall survival as a function of time between diagnosis and surgery in 4 intervals (1-2, 3-4, 5-6, >6 weeks). Results The Medicare cohort demonstrated an adjusted 5-year survival of 8% to 14% higher in patients with a surgical delay between 3 and 6 weeks, with significantly lower hazard ratios in that interval. The National Cancer Database cohort demonstrated an adjusted 5-year survival of 9% to 16% higher in patients with surgery 3 to 6 weeks after diagnosis, with comparatively similar improvements in survival hazard. Limitations Because this was a retrospective study of administrative databases, with Medicare data limited to billing data, the causality of outcomes must be interpreted with caution. Conclusions The ideal timing of definitive resection in colon cancer is between 3 and 6 weeks after initial diagnosis. All efforts should be made for patients to obtain definitive surgery within this interval to achieve a modest but significant improvement in overall survival. See Video Abstract at http://links.lww.com/DCR/B76. ?CUANDO DEBEN SOMETERSE LOS PACIENTES CON CANCER DE COLON A UNA RESECCION DEFINITIVA?: Se ha demostrado que el momento de la cirugia afecta los resultados en muchas formas de cancer, pero no existen datos nacionales definitivos para determinar el efecto del tiempo hasta la cirugia en la supervivencia en el cancer de colon.Determinar si un retraso en la cirugia definitiva en el cancer de colon afecta significativamente la supervivencia.Un estudio de cohorte retrospectivo que utiliza dos bases de datos independientes basadas en la poblacion; Se realizo la base de datos vinculada a la vigilancia, la epidemiologia y los resultados finales y la base de datos nacional del cancer.Pacientes con cancer de colon en estadios 1 a 3 del Comite Estadounidense Conjunto sobre el Cancer. Los pacientes tenian mas de 18 anos en la cohorte de la National Cancer Database y mas de 66 anos en la cohorte de Medicare. Los pacientes tuvieron un minimo de 3 anos de seguimiento.El resultado principal fue la supervivencia general en funcion del tiempo entre el diagnostico y la cirugia en 4 intervalos (1-2, 3-4, 5-6, y mas de 6 semanas).La cohorte de Medicare demostro una supervivencia ajustada de 5 anos de 8 a 14% mas en pacientes con un retraso quirurgico entre 3 a 6 semanas, con razones de riesgo significativamente mas bajas en ese intervalo. La cohorte de la National Cancer Database demostro una supervivencia ajustada a 5 anos de 9 a 16% mas en pacientes con cirugia de 3 a 6 semanas despues del diagnostico, con mejoras comparativamente similares en el riesgo de supervivencia.Dado que este fue un estudio retrospectivo de bases de datos administrativas, con datos de Medicare limitados a datos de facturacion, la causalidad de los resultados debe interpretarse con precaucion.El momento ideal para la reseccion definitiva en el cancer de colon es entre tres y seis semanas despues del diagnostico inicial. Se deben hacer todos los esfuerzos para que los pacientes obtengan una cirugia definitiva dentro de este intervalo para lograr una mejora modesta pero significativa en la supervivencia general. Consulte Video Resumen en http://links.lww.com/DCR/B76.

Metabolism in cancer cells is rewired to generate sufficient energy equivalents and anabolic precursors to support high proliferative activity. Within the context of these competing drives aerobic glycolysis is inefficient for the cancer cellular energy economy. Therefore, many cancer types, including colon cancer, reprogram mitochondria-dependent processes to fulfill their elevated energy demands. Elevated glycolysis underlying the Warburg effect is an established signature of cancer metabolism. However, there are a growing number of studies that show that mitochondria remain highly oxidative under glycolytic conditions. We hypothesized that activities of glycolysis and oxidative phosphorylation are coordinated to maintain redox compartmentalization. We investigated the role of mitochondria-associated malate-aspartate and lactate shuttles in colon cancer cells as potential regulators that couple aerobic glycolysis and oxidative phosphorylation. We demonstrated that the malate-aspartate shuttle exerts control over NAD+ /NADH homeostasis to maintain activity of mitochondrial lactate dehydrogenase and to enable aerobic oxidation of glycolytic l-lactate in mitochondria. The elevated glycolysis in cancer cells is proposed to be one of the mechanisms acquired to accelerate oxidative phosphorylation.

Many complex, natural landscapes have been transformed into simpler agroecosystems by continuous cropping and the application of glyphosate and fertilizers. The current mosaic with different land cover types can harbor different soil microbial communities. Here, we investigated how the microbial community and ryegrass plants responded to glyphosate and nitrogen application to soils from four different cover types (soybean monocropping; wheat/soybean-field pea rotation, herbaceous- and woody- uncropped margins). We predict that soils from different land cover types will display different responses of their detritivore microbial communities and plant growth to herbicide and fertilizer application. All the studied variables differed among land cover types. Woody margins tripled the soil carbon content and the microbial respiration of herbaceous margins, although the later had more diverse soil microbial communities. Soils from soybean monoculture had higher respiration rates (37%) than those from crop rotation, where ryegrass accumulated lower biomass (12% lower). Despite these differences between land cover types, neither glyphosate nor nitrogen fertilization significantly influenced these properties. Only ryegrass plants growing on glyphosate-treated soils accumulated more biomass than the rest whereas they did not respond to nitrogen. These results suggest that glyphosate and nitrogen at recommended doses did not have a significant impact on the soil performance of the different types of cover.

Background Nursing home residents undergoing surgery have a higher rate of postoperative adverse outcomes than nonnursing home patients. This study seeks to determine what contribution nursing home status makes to theses occurrences, independent of comorbid conditions. Methods Using the American College of Surgeons-National Surgical Quality Improvement Program (ACS-NSQIP) database, the 30-day postoperative outcomes of the 5 commonest nonemergent inpatient procedures performed on nursing home residents were compared with those in nonnursing home residents using logistic regression analysis. Results Nursing home status was found to be an independent risk factor for septic complications in all procedures, for blood transfusion requirement after lower leg amputation, for pneumonia and stroke/cerebrovascular accident after thromboendarterectomy, and for mortality after partial colectomy with primary anastomosis. Conclusions These data suggest that, in addition to serving as a surrogate indicator of health status and current morbidity, residence in a nursing home makes an independent contribution to adverse postoperative outcomes.

The decline of bees is a major concern due to their vital role inpollinating many crops and wild plants. Some regions in SouthAmerica, and especially the Pampas, are amongst those parts ofthe world where stressors of bee populations have been littlestudied. The Pampas has been intensively transformed for agriculture,being presently one of the most productive areas of agriculturalcommodities in the world. Here, we aim to provide firstinsights on the taxonomic and functional composition of beeassemblages in the Rolling Pampa, the most intensively managedpart of the Pampas. Soybean (herbicide-tolerant genetically modifiedvarieties) is the predominant crop in this region. Bees weresampled with coloured pan traps. Sampling points were locatedon field margins in either the cropped or the semi-natural grasslandarea of a farmland site devoted to annual cropping. A total of2384 individuals were caught, representing 33 taxa [mainly (morpho)species]. The subgenus Lasioglossum (Dialictus) largely dominatedcaptures (78% of the total abundance) and was relativelyabundant in the entire study area, suggesting that some speciesare likely to reach their ecological requirements in cropped areas.No-till fields and field margins may provide large areas for thesebelow-ground nesting species, while their polylectic food preferencesallow them to collect pollen on a wide range of plantspecies, among them possibly soybean. On the contrary, the richnessand the abundance of other taxa were higher in the seminaturalarea than in the cropped area. Among them, abovegroundnesting or oil-collecting species, which have more specialisednesting and floral requirements, were highly associated withthe semi-natural area. Our findings highlight the large dominanceof L. (Dialictus) species in this highly intensively managed landscape,and the urgent need of preserving semi-natural habitats tomaintain species-rich and functionally diverse bee communities inthe Pampas. Fil: Le Féon, Violette. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina. Institut National de la Recherche Agronomique; Francia Fil: Poggio, Santiago Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina Fil: Torretta, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario; Argentina. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Recursos Naturales y Ambiente. Cátedra de Botánica Agrícola; Argentina Fil: Bertrand, Colette. Institut National de la Recherche Agronomique; Francia Fil: Molina, Gonzalo Alberto Roman. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina Fil: Burel, Françoise. Universite de Rennes I; Francia. Centre National de la Recherche Scientifique; Francia Fil: Baudry, Jacques. Institut National de la Recherche Agronomique; Francia Fil: Ghersa, Claudio Marco. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina

Landscape fragmentation and farming can affect the diversity of plants and pollinators harbored by linear landscape elements (LLE) in agroecosystems. To assess the role of these habitats in sustaining plant-pollinator communities, twenty portions of LLE (road verges) were studied during two consecutive field seasons in the Argentine Pampas. A hierarchical approach was taken, describing three features of road verges in different scales of observation: width of the road verge (local scale), the land use of the neighboring fields (adjacent land use scale), and landscape heterogeneity (landscape scale). The influence of these features on the composition and abundance of entomophilous flowering plants and their visitors were examined with GLMMs. Plant and flower visitor communities in road verges were dominated by alien species. The local scale feature was the most influential, as the widest road verges had higher plant richness and higher flower visitor abundance. Contrary to our expectations, richness and abundance of both plants and flower visitors were not related to adjacent land use or landscape heterogeneity. These results suggest that the conservation and management of wider road verges should be a priority to sustain high species diversity in intensely managed agroecosystems.

Review. Research and teaching at the intersection: Navigating the territory of grammar and writing in the context of metalinguistic activity, edited by Anna Camps and Xavier Fontich, 2020