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Este trabajo ofrece una visión panorámica del proceso de debilitamiento y pérdida de /-s/ postnuclear en español. En primer lugar, se presentan las tendencias lingüísticas generales que operan sobre este rasgo variable en las distintas comunidades de habla y que dan lugar a fenómenos similares en otras lenguas; a continuación se describen los principales continuos de variación de /-s/ en coda en el español europeo y americano y se comparan los resultados de diferentes trabajos de corte sociolingüístico realizados sobre distintas comunidades de habla. Por último, se presentan los primeros resultados de un análisis conjunto, realizado dentro del marco del proyecto Preseea, en dos variedades del español que contrastan en sus patrones de realización de este segmento: Vallecas, una variedad conservadora que presenta índices relativamente altos de aspiración favorecidos por determinados grupos sociales y Málaga, una variedad innovadora en la que la aspiración está determinada, principalmente, por factores internos.

Presentamos el caso de una paciente de 35 años con diagnóstico de síndrome de aorta media congénita corregida en la infancia con bypass aórtico con interposición de un conducto de dacrón. Durante el seguimiento fue diagnosticada de hipertensión arterial por lo que se inició tratamiento antihipertensivo y se implantó un stent en el conducto. En un TC de aorta de control se apreció una lesión costal sugestiva de osteocondroma que comprimía el conducto. Se realizó un cateterismo cardiaco que confirmó la estenosis hemodinámica por compresión extrínseca de la lesión costal a nivel del stent implantado previamente. El estudio con imagen con TC ayudó a diagnosticar una complicación a nivel de la aorta que había pasado desapercibida en otras técnicas de imagen.

When disaggregation of national estimates in several domains or areas is required, direct survey estimators, which use only the domain-specific survey data, are usually design-unbiased even under complex survey designs (at least approximately) and require no model assumptions. Nevertheless, they are appropriate only for domains or areas with sufficiently large sample size. For example, when estimating poverty in a domain with a small sample size (small area), the volatility of a direct estimator might make that area seems like very poor in one period and very rich in the next one. Small area (or indirect) estimators have been developed in order to avoid such undesired instability. Small area estimators borrow strength from the other areas so as to improve the precision and therefore obtain much more stable estimators. However, the usual model-based assumptions, which include some kind of area homogeneity, may not hold in real applications. A more flexible model based on multivariate mixtures of normal distributions that generalises the usual nested error linear regression model is proposed for estimation of general parameters in small areas. This flexibility makes the model adaptable to more general situations, where there may be areas with a different behaviour from the other ones, making the model less restrictive (hence, more close to nonparametric) and more robust to outlying areas. An expectation-maximisation (E-M) method is designed for fitting the proposed mixture model. Under the proposed mixture model, two different new predictors of general small area indicators are proposed. A parametric bootstrap method is used to estimate the mean squared errors of the proposed predictors. Small sample properties of the new predictors and of the bootstrap procedure are analysed by simulation studies and the new methodology is illustrated with an application to poverty mapping in Palestine.

El Colegio de México, a través del Centro de Estudios Demográficos, Urbanos y Ambientales (CEDUA), organizó una Celebración a la Trayectoria de Manuel Ángel Castillo. El homenaje se llevó a cabo en la Sala Alfonso Reyes de la institución, el 5 de abril de 2022. Participaron Gustavo Garza (Programa de Estudios Interdisciplinarios, Colmex), Martha Rojas (El Colegio de la Frontera Sur), Jéssica Nájera (CEDUA, Colmex), Leticia Argüelles (editora de Estudios Demográficos y Urbanos, CEDUA, Colmex), Silvia Giorguli (presidenta de El Colegio de México), María Isabel Molina (esposa del homenajeado) y, por último, Manuel Ángel Castillo, quien pronunció unas palabras de agradecimiento. El acto fue organizado y moderado por Landy Sánchez (directora del CEDUA). A continuación, incluimos las participaciones de los expositores, en el orden de su presentación.

Chlamydia trachomatis is an obligate intracellular pathogen and the leading bacterial cause of sexually transmitted infections worldwide. Chlamydia trachomatis genovars L1–L3 are responsible for lymphogranuloma venereum (LGV), an invasive sexually transmitted disease endemic in tropical and subtropical regions of Africa, South America, the Caribbean, India and South East Asia. The typical signs and symptoms of C. trachomatis LGV urogenital infections in men include herpetiform ulcers, inguinal buboes, and/or lymphadenopathies. Since 2003, endemic cases of proctitis and proctocolitis caused by C. trachomatis LGV emerged in Europe, mainly in HIV-positive men who have sex with men (MSM). Scarce data have been reported about unusual clinical presentations of C. trachomatis LGV urogenital infections. Herein, we report a case of a 36-year-old heterosexual, HIV-negative male declaring he did not have sex with men or trans women, who presented to the Urology and Andrology outpatient clinic of a healthcare center from Cordoba, Argentina, with intermittent testicular pain over the preceding 6 months. Doppler ultrasound indicated right epididymitis and funiculitis. Out of 17 sexually transmitted infections (STIs) investigated, a positive result was obtained only for C. trachomatis. Also, semen analysis revealed oligoasthenozoospermia, reduced sperm viability as well as increased sperm DNA fragmentation and necrosis, together with augmented reactive oxygen species (ROS) levels and the presence of anti-sperm IgG autoantibodies. In this context, doxycycline 100 mg/12 h for 45 days was prescribed. A post-treatment control documented microbiological cure along with resolution of clinical signs and symptoms and improved semen quality. Strikingly, sequencing of the ompA gene revealed C. trachomatis LGV L2 as the causative uropathogen. Remarkably, the patient did not present the typical signs and symptoms of LGV. Instead, the infection associated with chronic testicular pain, semen inflammation and markedly reduced sperm quality. To our knowledge, this is the first reported evidence of chronic epididymitis due to C. trachomatis LGV L2 infection in an HIV-negative heterosexual man. These findings constitute important and valuable information for researchers and practitioners and highlight that C. trachomatis LGV-L2 should be considered as putative etiologic agent of chronic epididymitis, even in the absence of the typical LGV signs and symptoms.

Melanoma cells express the chemokine receptor CXCR4, which confers invasive signals on binding to its ligand CXCL12. We show here that knocking down membrane-type matrix metalloproteinase (MT1-MMP) expression translates into a blockade of invasion across reconstituted basement membranes and type I collagen gels in response to CXCL12, which is the result of lack of MMP-2 activation. Interference with MMP-2 expression further confirms its important role during this invasion. Vav proteins are guanine-nucleotide exchange factors for Rho GTPases that regulate actin dynamics and gene expression. We show that melanoma cells express Vav1 and Vav2, which are activated by CXCL12 involving Jak activity. Blocking Vav expression by RNA interference results in impaired activation of Rac and Rho by CXCL12 and in a remarkable inhibition of CXCL12-promoted invasion. Importantly, up-regulation of MT1-MMP expression by CXCL12, a mechanism contributing to melanoma cell invasion, is blocked by knocking down Vav expression or by inhibiting Jak. Together, these data indicate that activation of Jak/Vav/Rho GTPase pathway by CXCL12 is a key signaling event for MT1-MMP/MMP-2–dependent melanoma cell invasion. (Cancer Res 2006; 66(1): 248-58)

Supplementary Figure 6A-C from Activated Gα13 Impairs Cell Invasiveness through p190RhoGAP-Mediated Inhibition of RhoA Activity

Supplementary Figure Legends 1-2 from Activation of Vav/Rho GTPase Signaling by CXCL12 Controls Membrane-Type Matrix Metalloproteinase–Dependent Melanoma Cell Invasion

Supplementary Table 1 from Activated Gα13 Impairs Cell Invasiveness through p190RhoGAP-Mediated Inhibition of RhoA Activity

Supplementary Figures 1-2 from Activation of Vav/Rho GTPase Signaling by CXCL12 Controls Membrane-Type Matrix Metalloproteinase–Dependent Melanoma Cell Invasion

Supplementary Figures 1-4 from Activated Gα13 Impairs Cell Invasiveness through p190RhoGAP-Mediated Inhibition of RhoA Activity

Supplementary Figure 5 from Activated Gα13 Impairs Cell Invasiveness through p190RhoGAP-Mediated Inhibition of RhoA Activity

Supplementary Figure Legends 1-7, references from Activated Gα13 Impairs Cell Invasiveness through p190RhoGAP-Mediated Inhibition of RhoA Activity

Supplementary Figure 7 from Activated Gα13 Impairs Cell Invasiveness through p190RhoGAP-Mediated Inhibition of RhoA Activity

Supplementary Figure 6D-E from Activated Gα13 Impairs Cell Invasiveness through p190RhoGAP-Mediated Inhibition of RhoA Activity

La cardiorresonancia magnética-4DFlow es una técnica relativamente novedosa que permite la evaluación de flujos en las tres dimensiones del espacio más una cuarta representada por el tiempo a lo largo del ciclo cardíaco. La comunicación interauricular (CIA) tipo ostium secundum (OS) es el defecto interauricular de origen congénito más frecuente. Se presentan los estudios de cuatro pacientes con diagnóstico de CIA-OS valorados con cardiorresonancia-4DFlow en nuestro centro, poniendo de manifiesto la enorme utilidad cuali-cuantitativa de la técnica en esta patología congénita

This study aims to examine the relationship between working memory, inhibitory control, and cognitive flexibility with the referential skills of using appropriate ways to introduce, reintroduce, and maintain references to characters in a story, after controlling for the role of age and vocabulary. To examine the relationship between working memory, inhibitory control, and cognitive flexibility with the referential skills of using appropriate ways to introduce, reintroduce, and maintain references to characters in a story, after controlling for the role of age and vocabulary. For this purpose, a secondary use of data will be made with which several mixed models will be performed with the referential skills variables as predictor variables and those of executive functions, vocabulary and age in months as predictor variables. The sample is composed of 88 preschool boys and girls from urban areas of Costa Rica.

Cutin and suberin are lipid polyesters deposited in specific apoplastic compartments. Their fundamental roles in plant biology include controlling the movement of gases, water and solutes, and conferring pathogen resistance. Both cutin and suberin have been shown to be present in the Arabidopsis seed coat where they regulate seed dormancy and longevity. In this study, we use accelerated and natural ageing seed assays, glutathione redox potential measures, optical and transmission electron microscopy and gas chromatography-mass spectrometry to demonstrate that increasing the accumulation of lipid polyesters in the seed coat is the mechanism by which the AtHB25 transcription factor regulates seed permeability and longevity. Chromatin immunoprecipitation during seed maturation revealed that the lipid polyester biosynthetic gene long-chain acyl-CoA synthetase 2 (LACS2) is a direct AtHB25 binding target. Gene transfer of this transcription factor to wheat and tomato demonstrated the importance of apoplastic lipid polyesters for the maintenance of seed viability. Our work establishes AtHB25 as a trans-species regulator of seed longevity and has identified the deposition of apoplastic lipid barriers as a key parameter to improve seed longevity in multiple plant species.

This paper presents a methodological update to the World Bank's toolkit for small area estimation. The paper reviews the computational procedures of the current methods used by the institution: the traditional ELL approach and the Empirical Best (EB) addition introduced to imitate the original EB procedure of Molina and Rao [Small area estimation of poverty indicators. Canadian J Stat. 2010;38(3):369–385], including heteroskedasticity and survey weights, but using a different bootstrap approach, here referred to as clustered bootstrap. Simulation experiments provide empirical evidence of the shortcomings of the clustered bootstrap approach, which yields biased and noisier point estimates. The document presents an update to the World Bank’s EB implementation by considering the original EB procedures for point and noise estimation, extended for complex designs and heteroscedasticity. Simulation experiments illustrate that the revised methods yield considerably less biased and more efficient estimators than those obtained from the clustered bootstrap approach.

Physical dormancy in seeds exists widely in seed plants and plays a vital role in maintaining natural seed banks. The outermost cuticle of the seed coat forms a water-impermeable layer, which is critical for establishing seed physical dormancy. We previously set up the legume plant Medicago truncatula as an excellent model for studying seed physical dormancy, and our studies revealed that a class II KNOTTED-like homeobox, KNOX4, is a transcription factor critical for controlling hardseededness. Here we report the function of a seed coat β-ketoacyl-CoA synthase, KCS12. The expression level of KCS12 is significantly downregulated in the knox4 mutant. The KCS12 gene is predominantly expressed in the seed coat, and seed development in the M. truncatula kcs12 mutant is altered. Further investigation demonstrated that kcs12 mutant seeds lost physical dormancy and were able to absorb water without scarification treatment. Chemical analysis revealed that concentrations of C24:0 lipid polyester monomers are significantly decreased in mutant seeds, indicating that KCS12 is an enzyme that controls the production of very long chain lipid species in the seed coat. A chromatin immunoprecipitation assay demonstrated that the expression of KCS12 in the seed coat is directly regulated by the KNOX4 transcription factor. These findings define a molecular mechanism by which KNOX4 and KCS12 control formation of the seed coat and seed physical dormancy.

This study determined productive performance, ruminal fermentation kinetics and rumen ciliate protozoa in hair sheep lambs fed different levels of olive oil. Twenty-four growing lambs were used, with an initial live weight of 10.5 ± 2.9 kg, and randomly assigned into four treatments (six animals per treatment) containing increasing levels of extra virgin olive oil (0, 2, 4 and 6% of dry matter). Animals were fed for 80 days, and sampling was carried out weekly. Intake of dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and metabolizable energy (ME) differed between treatments (p < 0.05), with a linear and cubic tendency to decrease when oil concentrations were increased. Digestibility coefficients of OM, CP and NDF were not affected; however, the relationship between total intake and nutrient digestibility (DM, OM, NDF, ADF) increased with 2% DM olive oil. Compared with all treatments, the concentration of propionic acid increased by 16% with 4% olive oil. The intake of olive oil did not affect the protozoa population and live weight gain. Overall, the inclusion of olive oil in low concentrations (2% of DM) positively influences feed intake and nutrient digestibility in hair sheep lambs.

Pulmonary vein (PV) isolation is a well-established rhythm control therapy in atrial fibrillation (AF). Currently, there is no consensus on which ablation technique to use for the first procedure, cryoballoon (CB) or radiofrequency (RF). A retrospective cohort study was conducted on 1055 patients who underwent a first ablation, to assess both techniques based on the need for reablation. Patients with CB (n = 557) and RF (n = 498) ablations were clinically characterized and the need for reablation during a 30-month follow-up was used as the primary endpoint. Independent variables were analyzed to identify potential predictors. The need for reablation was significantly lower in the CB group than in the RF group (hazard ratio = 0.45 and 95% confident interval = 0.32–0.61; p < 0.001); in both paroxysmal and persistent AF, using a full-adjusted regression Cox model by age, sex, smoking, hypertension, diabetes mellitus, dyslipidemia, severe obstructive sleep apnea, dilated left atrium, persistent AF and early recurrence. RF ablation, dilated left atrium, persistent AF and early recurrence were identified as independent predictors of reablation. In addition, the CB-redo subgroup had a lower PV reconnection than the RF-redo subgroup. In conclusion, CB ablation suggests a reduction in the need for reablation and lower PV reconnection during the follow-up than RF ablation.

The cuticle, a hydrophobic layer of cutin and waxes synthesized by plant epidermal cells, is the major barrier to water loss when stomata are closed. Dissecting the genetic architecture of natural variation for maize (Zea mays L.) leaf cuticular conductance (gc) is important for identifying genes relevant to improving crop productivity in drought-prone environments. To this end, we performed an integrated genome- and transcriptome-wide association studies (GWAS and TWAS) to identify candidate genes putatively regulating variation in leaf gc. Of the 22 plausible candidate genes identified, 4 were predicted to be involved in cuticle precursor biosynthesis and export, 2 in cell wall modification, 9 in intracellular membrane trafficking, and 7 in the regulation of cuticle development. A gene encoding an INCREASED SALT TOLERANCE1-LIKE1 (ISTL1) protein putatively involved in intracellular protein and membrane trafficking was identified in GWAS and TWAS as the strongest candidate causal gene. A set of maize nested near-isogenic lines that harbor the ISTL1 genomic region from eight donor parents were evaluated for gc, confirming the association between gc and ISTL1 in a haplotype-based association analysis. The findings of this study provide insights into the role of regulatory variation in the development of the maize leaf cuticle and will ultimately assist breeders to develop drought-tolerant maize for target environments.

Caracterizar física y químicamente las arcillas utilizadas en la preparación de pastas cerámicas para la producción de los lotes de ladrillo tipo H-10 en la empresa Ladrillera Valledupar S.A.S. Para el cumplimiento de los objetivos de la investigación se llevó a cabo una fase de revisión documental en las diferentes bases de datos científicas; posteriormente una etapa de campo, donde se realizaron seis (6) apiques, se recolectaron cinco (5) muestras. A tres (3) de las muestras (A2-C1 Arcilla (N) Negra, A4-C1 Arcilla (T) Tierra y A1-C3 Arcilla (P) Parda) se les aplicaron ensayos de fluorescencia de rayos X (FRX–XRF). Las propiedades físicas fueron evaluadas con el índice de plasticidad de Attenberg, mediante cazuela Casagrande, kit para determinar el limite líquido y ensayos de resistencia a la compresión y absorción de agua (NTC 4205-2 / 2009, NTC 4017 / 2018). Se determinó que las arcillas negras y pardas comparten composiciones químicas (Si, Al y Fe), los cuales son predominantes el K, Mg, Ca, Na y Ti, además presentan promedio % absorción de agua de 9.882 a 12.23 y promedio de resistencia a la compresión de 1.748 a 2.334. La composición química de la arcilla tierra A4-C1 por sí sola no es la más apropiada para la fabricación de productos cerámicos, dada sus altas concentraciones de silicio y bajas concentraciones de alúmina que sobrepasan el 70% y recaen en 16% respectivamente.

El Ecuador, cuenta con una amplia dinámica geológica, variedad climática y diversidad natural, lo que la constituye como un atractivo para el mundo, conformada por playas, planicies, alta humedad de las selvas orientales, así como la majestuosidad de la cordillera andina, sitio en la que se puede apreciar 27 volcanes, siendo el volcán Tungurahua uno de los más atractivos de toda la región. El Proyecto Geoparque Volcán Tungurahua PGVT nace con la intención de aprovechar los geositios para el desarrollo de actividades de turismo científico lo que ha orientado esta investigación que inicia con una caracterización del PGVT, posteriormente se realiza un análisis de los geoparques más representativos de América Latina y finalmente una comparación de bondades entre los geoparques identificados y PGVT, por medio del análisis descriptivo cuantitativo simple se procedió a la caracterización, con la ayuda de los componentes propuestos por Pereira 2007 consistentes en valor intrínseco, uso potencial y necesidad de protección, para posteriormente analizar los geoparques más representativos y finalmente un análisis comparativo para establecer en que rango se encuentra el PGVT; llegando a determinar en el PGVT 16 geositios de importancia y 3 no geológicos, 8 geoparques representativos de América Latina y se establece al PGVT como dentro del rango de los otros geositios con un valor sumado de 24, puntaje que se encuentra en la media aritmética de los 8 geoparques evaluados, determinando así que Baños de Agua Santa cuenta con las condiciones para generar geoturismo.

This paper offers a sociolinguistic analysis of the consonants (s) and (d) in the coda position in the city of Madrid, within the framework of the Project for the Sociolinguistic Study of Spanish from Spain and America (PRESEEA). The purpose is to illustrate how varieties of southern Castilian Spanish and those from the central and northern Peninsula converge and diverge, taking into consideration the social, political, and economic parameters that affect said processes. The diversity of patterns that coexist in the Madrid speech community reflects the city’s historic social complexity, the varied geographical origins of its migrant population, the interests that motivate each community of practice, as well as other circumstances that influence the direction of change. The analysis of (s) and (d) in coda illustrates the way in which the dynamics of variation and change in Madrid fluctuate between two poles: standardization and regionalization, the same two axes around which the community’s sociolinguistic patterns revolve.

Summary All aerial epidermal cells in land plants are covered by the cuticle, an extracellular hydrophobic layer that provides protection against abiotic and biotic stresses and prevents organ fusion during development.Genetic and morphological analysis of the classic maize adherent1 (ad1) mutant was combined with genome‐wide binding analysis of the maize MYB transcription factor FUSED LEAVES1 (FDL1), coupled with transcriptional profiling of fdl1 mutants.We show that AD1 encodes an epidermally‐expressed 3‐KETOACYL‐CoA SYNTHASE (KCS) belonging to a functionally uncharacterized clade of KCS enzymes involved in cuticular wax biosynthesis. Wax analysis in ad1 mutants indicates that AD1 functions in the formation of very‐long‐chain wax components. We demonstrate that FDL1 directly binds to CCAACC core motifs present in AD1 regulatory regions to activate its expression. Over 2000 additional target genes of FDL1, including many involved in cuticle formation, drought response and cell wall organization, were also identified.Our results identify a regulatory module of cuticle biosynthesis in maize that is conserved across monocots and eudicots, and highlight previously undescribed factors in lipid metabolism, transport and signaling that coordinate organ development and cuticle formation.

[EN] Thousands of deaths associated with air pollution each year could be prevented by forecasting the behavior of factors that pose risks to people's health and their geographical distribution. Proximity to pollution sources, degree of urbanization, and population density are some of the factors whose spatial distribution enables the identification of possible influence on the presence of respiratory diseases (RD). Currently, Bogota is among the cities with the poorest air quality in Latin America. Specifically, the locality of Kennedy is one of the zones in the city with the highest recorded concentration levels of local pollutants over the last 10 years. From 2009 to 2016, there were 8619 deaths associated with respiratory and cardiovascular diseases in the locality. Given these characteristics, this study set out to identify and analyze the areas in which the primary socioeconomic and environmental conditions contribute to the presence of symptoms associated with RD. To this end, information collected in field by performing georeferenced surveys was analyzed through geostatistical and machine learning tools which carried out cluster and pattern analyses. Random forests and AdaBoost were applied to establish hot spots where RD could occur, given the conjugation of predictor variables in the micro-territory. It was found that random forests outperformed AdaBoost with 0.63 AUC. In particular, this study's approach applies to densely populated municipalities with high levels of air pollution. In using these tools, municipalities can anticipate environmental health situations and reduce the cost of respiratory disease treatments., Many thanks to the members of the Intelligence and Territorial Analysis Group of the Universidad Santo Tomás for their collaboration in conducting the fieldwork.

Significance Plant cuticles provide barriers to water loss and arose as aquatic plants adapted to the dry terrestrial environment. The cuticle components, waxes and the fatty acid-based polymer cutin, are synthesized in the plant epidermis, exported across the cell wall, and deposited on the plant surface. This study suggests a role for PHYTOCHROME light receptors during cuticle development in leaves of maize and moss, diverse species that are separated by more than 400 million y of land plant evolution. We hypothesize that phytochrome-mediated light signaling contributed to the evolution of cuticles in land plants., Plant cuticles are composed of wax and cutin and evolved in the land plants as a hydrophobic boundary that reduces water loss from the plant epidermis. The expanding maize adult leaf displays a dynamic, proximodistal gradient of cuticle development, from the leaf base to the tip. Laser microdissection RNA Sequencing (LM-RNAseq) was performed along this proximodistal gradient, and complementary network analyses identified potential regulators of cuticle biosynthesis and deposition. A weighted gene coexpression network (WGCN) analysis suggested a previously undescribed function for PHYTOCHROME-mediated light signaling during the regulation of cuticular wax deposition. Genetic analyses reveal that phyB1 phyB2 double mutants of maize exhibit abnormal cuticle composition, supporting the predictions of our coexpression analysis. Reverse genetic analyses also show that phy mutants of the moss Physcomitrella patens exhibit abnormal cuticle composition, suggesting an ancestral role for PHYTOCHROME-mediated, light-stimulated regulation of cuticle development during plant evolution.

The cuticle, a hydrophobic layer of cutin and waxes synthesized by plant epidermal cells, is the major barrier to water loss when stomata are closed at night and under water-limited conditions. Elucidating the genetic architecture of natural variation for leaf cuticular conductance (gc) is important for identifying genes relevant to improving crop productivity in drought-prone environments. To this end, we conducted a genome-wide association study ofgcof adult leaves in a maize inbred association panel that was evaluated in four environments (Maricopa, AZ, and San Diego, CA in 2016 and 2017). Five genomic regions significantly associated withgcwere resolved to seven plausible candidate genes (ISTL1, two SEC14 homologs, cyclase-associated protein, a CER7 homolog, GDSL lipase, and β-D-XYLOSIDASE 4). These candidates are potentially involved in cuticle biosynthesis, trafficking and deposition of cuticle lipids, cutin polymerization, and cell wall modification. Laser microdissection RNA sequencing revealed that all these candidate genes, with the exception of the CER7 homolog, were expressed in the zone of the expanding adult maize leaf where cuticle maturation occurs. With direct application to genetic improvement, moderately high average predictive abilities were observed for whole-genome prediction ofgcin locations (0.46 and 0.45) and across all environments (0.52). The findings of this study provide novel insights into the genetic control ofgcand have the potential to help breeders more effectively develop drought-tolerant maize for target environments.Article summaryThe cuticle serves as the major barrier to water loss when stomata are closed at night and under water-limited conditions and potentially relevant to drought tolerance in crops. We performed a genome-wide association study to elucidate the genetic architecture of natural variation for maize leaf cuticular conductance. We identified epidermally expressed candidate genes that are potentially involved in cuticle biosynthesis, trafficking and deposition, cutin polymerization, and cell wall modification. Finally, we observed moderately high predictive abilities for whole-genome prediction of leaf cuticular conductance. Collectively, these findings may help breeders more effectively develop drought-tolerant maize.

Upon mechanical damage, plants produce wound responses to protect internal tissues from infections and desiccation. Suberin, a heteropolymer found on the inner face of primary cell walls, is deposited in specific tissues under normal development, enhanced under abiotic stress conditions and synthesized by any tissue upon mechanical damage. Wound-healing suberization of tree bark has been investigated at the anatomical level but very little is known about the molecular mechanisms underlying this important stress response. Here, we investigated a time course of wound-induced suberization in poplar bark. Microscopic changes showed that polyphenolics accumulate 3 days post wounding, with aliphatic suberin deposition observed 5 days post wounding. A wound periderm was formed 9 days post wounding. Chemical analyses of the suberin polyester accumulated during the wound-healing response indicated that suberin monomers increased from 0.25 to 7.98 mg/g DW for days 0 to 28, respectively. Monomer proportions varied across the wound-healing process, with an overall ratio of 2:1 (monomers:glycerol) found across the first 14 days post wounding, with this ratio increasing to 7:2 by day 28. The expression of selected candidate genes of poplar suberin metabolism was investigated using qRT-PCR. Genes queried belonging to lipid polyester and phenylpropanoid metabolism appeared to have redundant functions in native and wound-induced suberization. Our data show that, anatomically, the wounding response in poplar bark is similar to that described in periderms of other species. It also provides novel insight into this process at the chemical and molecular levels, which have not been previously studied in trees.