DNA use in forensic human identification

Abstract in proceedings of the Fourth International Congress of CiiEM: Health, Well-Being and Ageing in the 21st Century, held at Egas Moniz’ University Campus in Monte de Caparica, Almada, from 3–5 June 2019.This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.info:eu-repo/semantics/publishedVersio

Public High School Principals’ Perceptions of Leadership Strategies for Improved School Performance

The purpose of this study was to explore what leadership behaviors and strategies public high school principals perceived to be most effective in achieving school improvement. The qualitative constructivist grounded theory research methodology used for the study was modeled after the work of Kathy Charmaz (2014), who acknowledges that the researcher is a part of the process, as observer, data collector, analyzer, and interpreter of the data. Data were gathered through one-on-one interviews with six principals from high schools with student populations of 1,200 or more whose schools showed improvement based on state standardized test scores and whose high schools were located in the metropolitan area surrounding the university where the researcher studied. The central research questions were: (1) How do public high school principals, who have been identified by the researcher as achieving school improvement, describe their leadership? and (2) Which of their leadership behaviors and strategies do the public high school principals perceive to be most effective in achieving the desired school improvement? Through coding and analysis, five common themes were identified, based on the converging perspectives of the participants. The common themes form the foundation of the grounded theory that emerged from this study. Fiedler’s Contingency Theory (1967), the theoretical framework for this study, defined leadership effectiveness in terms of group performance and the ability of the group to achieve its goals, and that theory was supported throughout the study. The participating principals facilitated strategies that were carried out by teams of administrators and teachers who were committed to school improvement, and the school improvement was measured by group performance and the ability of the group to achieve its goals. The school improvement theory that emerged from the data presents that five leadership strategies support school improvement and improved student learning and achievement. Those behaviors and strategies include (1) hiring and developing quality teachers; (2) setting and accomplishing campus goals (3) building relationships; (4) employing communication tactics; and (5) building effective teams. Perhaps most significant to this study are the importance of the school environment and culture and the principal’s ability to influence that environment and to facilitate the strategies identified in the common themes. The researcher suggests that building and sustaining a healthy and positive school culture is a collaborative process that is essential to accomplishing and sustaining school improvement. The principal leader is in a position to facilitate the change required to build a student-focused, collaborative culture. The key is to create the vision collaboratively, to define the desired culture together, and to undertake the work required to achieve the desired results as a campus team. As the school’s leader, the principal serves as facilitator. With the theory that the environment and culture create the foundation for school improvement and sustained student achievement, a model, grounded in the data, emerged

Cold treatment breaks dormancy but jeopardizes flower quality in Camellia japonica L.

Camellia japonica L. is an evergreen shrub whose cultivars are of great ornamental value. In autumn, after flower bud differentiation, dormancy is initiated. As in many other spring flowering woody ornamentals, winter low temperatures promote dormancy release of both flower and vegetative buds. However, warm spells during late autumn and winter can lead to unfulfilled chilling requirements leading to erratic and delayed flowering. We hypothesized that storing plants at no light and low temperature could favor dormancy breaking and lead to early and synchronized flowering in response to forcing conditions in C. japonica ‘Nuccio’s Pearl’. Plants with fully developed floral primordia were stored at dark, 7∘C, and RH > 90% for up to 8 weeks. To monitor endodormancy release during the storage, we evaluated the content of abscisic acid (ABA) in flower buds and the expression profiles of five putative genes related to dormancy and cold acclimation metabolism in leaves and flower buds. In addition, the expression of four anthocyanin biosynthesis pathway genes was profiled in flower buds to assess the effect of the treatment on flower pigment biosynthesis. At 0, 4, 6, and 8 weeks of cold treatment, 10 plants were transferred to the greenhouse and forced to flower. Forced plant flower qualities and growth were observed. The ABA content and the expression profiles of two dormancy-related genes (CjARP and CjDEH) suggested that dormancy breaking occurred after 6–8 weeks of cold treatment. Overall, plants treated for 6–8 weeks showed earlier vegetative sprouting, enhanced, and homogeneous flowering with reduced forcing time. Prolonged cold treatments also reduced flower size and longevity, anthocyanin content, and pigment biosynthesis-related gene transcripts. In conclusion, the cold treatment had a promotive effect on dormancy breaking but caused severe drawbacks on flower quality

Identification and substrate prediction of new Fragaria x ananassa aquaporins and expression in different tissues and during strawberry fruit development

The newly identified aquaporin coding sequences presented here pave the way for further insights into the plant-water relations in the commercial strawberry (Fragaria x ananassa). Aquaporins are water channel proteins that allow water to cross (intra) cellular membranes. In Fragaria x ananassa, few of them have been identified hitherto, hampering the exploration of the water transport regulation at cellular level. Here, we present new aquaporin coding sequences belonging to different subclasses: plasma membrane intrinsic proteins subtype 1 and subtype 2 (PIP1 and PIP2) and tonoplast intrinsic proteins (TIP). The classification is based on phylogenetic analysis and is confirmed by the presence of conserved residues. Substrate-specific signature sequences (SSSSs) and specificity-determining positions (SDPs) predict the substrate specificity of each new aquaporin. Expression profiling in leaves, petioles and developing fruits reveals distinct patterns, even within the same (sub) class. Expression profiles range from leaf-specific expression over constitutive expression to fruit-specific expression. Both upregulation and downregulation during fruit ripening occur. Substrate specificity and expression profiles suggest that functional specialization exists among aquaporins belonging to a different but also to the same (sub)class

Application of the iPLEXTM Gold SNP genotyping method for the analysis of Amerindian ancient DNA samples: Benefits for ancient population studies

Important developments in the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) technique have generated new perspectives regarding SNP genotyping, which are particularly promising for ancient population-based studies. The main aim of the present study was to investigate the application of a MALDI-TOF MS-based SNP genotyping technique, called iPLEX® Gold, to analyze Amerindian ancient DNA samples. The first objective was to test the sensitivity of the method, which is recommended for DNA quantities between 10 and 5ng, for ancient biological samples containing DNA molecules that were degraded and present in minute quantities. The second objective was to detail the advantages of this technique for studies on ancient populations. Two multiplexes were designed, allowing the major Amerindian mitochondrial and Y haplogroups to be determined simultaneously. This analysis has never been described before. Results demonstrated the reliability and accuracy of the method; data were obtained for both mitochondrial and nuclear DNA using picogram (pg) quantities of nucleic acid. This technique has the advantages of both MS and minisequencing techniques; thus, it should be included in the protocols for future ancient DNA studies.Fil: Mendisco, Fanny. Centre National de la Recherche Scientifique; Francia. Université de Strasbourg; FranciaFil: Keyser, Christine. Centre National de la Recherche Scientifique; Francia. Université de Strasbourg; FranciaFil: Hollard, Clémence. Université de Strasbourg; FranciaFil: Seldes, Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Secretaría de Cultura de la Nación. Dirección Nacional de Cultura y Museos. Instituto Nacional de Antropología y Pensamiento Latinoamericano; ArgentinaFil: Nielsen, Axel Emil. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Secretaría de Cultura de la Nación. Dirección Nacional de Cultura y Museos. Instituto Nacional de Antropología y Pensamiento Latinoamericano; ArgentinaFil: Crubézy, Eric. Centre National de la Recherche Scientifique; FranciaFil: Ludes, Bertrand. Centre National de la Recherche Scientifique; Francia. Université de Strasbourg; Franci

Schémas d’incisions et de fracture des différents morphotypes de dents adaptés au recueil de pulpes dentaires et à l’analyse d’ADN

Les facteurs de risques de contaminations croisées des échantillons de tissus destinés à l’étude de l’ADN ancien sont nombreux. La pulpe dentaire étant mieux protégée mais en faible quantité, nous avons mis au point une technique de fracture des différents morphotypes de dents qui nous permet de recueillir la totalité de la pulpe dans des conditions aseptiques.There are numerous risk factors for cross-contamination of tissue samples for DNA. As dental pulp is better protected but small in amount, we have developed a fracture technique for the different dental morphotypes which allows the total recovery of the pulp in aseptic conditions

Introgression of rol genes from rhizogenic Agrobacterium strains into Escallonia spp.

The introgression of rol-genes of rhizogenic Agrobacterium into the plant genome induces changes in plant phenotype and physiology. However, only limited experience with this technique is available for woody ornamentals. To induce new variation within the Escallonia genus, several species were co-cultivated with rhizogenic Agrobacterium strains. Co-cultivation of three rhizogenic Agrobacterium strains (Arqua1, LMG 63 and MAFF210266) with four Escallonia species (E. illinita, E. myrtoidea, E. rosea, and E. rubra), resulted in hairy roots production with a varying efficiency. Co-cultivation of E. rubra with MAFF210266, and E. myrtoidea with LMG63 did not yield hairy roots, while co-cultivation of E. rubra leaves with LMG63 was most successful for hairy root production (up to 80.6%). In addition, the efficiency of hairy root induction depended on the explant type (leaves or nodal sections). The presence of inserted rol-genes and aux-genes in hairy roots was molecularly confirmed using qPCR. Few shoots regenerated from hairy roots, but regeneration needs to be optimized for efficient implementation of rol-genes introgression in Escallonia breeding. Key Message: This research provides a protocol for the production of hairy roots with rol-genes inserted after co-cultivation of several species of Escallonia with rhizogenic Agrobacterium strains

Human evolution in Siberia: from frozen bodies to ancient DNA

<p>Abstract</p> <p>Background</p> <p>The Yakuts contrast strikingly with other populations from Siberia due to their cattle- and horse-breeding economy as well as their Turkic language. On the basis of ethnological and linguistic criteria as well as population genetic studies, it has been assumed that they originated from South Siberian populations. However, many questions regarding the origins of this intriguing population still need to be clarified (e.g. the precise origin of paternal lineages and the admixture rate with indigenous populations). This study attempts to better understand the origins of the Yakuts by performing genetic analyses on 58 mummified frozen bodies dated from the 15^thto the 19^thcentury, excavated from Yakutia (Eastern Siberia).</p> <p>Results</p> <p>High quality data were obtained for the autosomal STRs, Y-chromosomal STRs and SNPs and mtDNA due to exceptional sample preservation. A comparison with the same markers on seven museum specimens excavated 3 to 15 years ago showed significant differences in DNA quantity and quality. Direct access to ancient genetic data from these molecular markers combined with the archaeological evidence, demographical studies and comparisons with 166 contemporary individuals from the same location as the frozen bodies helped us to clarify the microevolution of this intriguing population.</p> <p>Conclusion</p> <p>We were able to trace the origins of the male lineages to a small group of horse-riders from the Cis-Baïkal area. Furthermore, mtDNA data showed that intermarriages between the first settlers with Evenks women led to the establishment of genetic characteristics during the 15^thcentury that are still observed today.</p

Viscoelastic properties of differentiating blood cells are fate- and function-dependent.

Although cellular mechanical properties are known to alter during stem cell differentiation, understanding of the functional relevance of such alterations is incomplete. Here, we show that during the course of differentiation of human myeloid precursor cells into three different lineages, the cells alter their viscoelastic properties, measured using an optical stretcher, to suit their ultimate fate and function. Myeloid cells circulating in blood have to be advected through constrictions in blood vessels, engendering the need for compliance at short time-scales (minutes), compared to undifferentiated cells. These findings suggest that reduction in steady-state viscosity is a physiological adaptation for enhanced migration through tissues. Our results indicate that the material properties of cells define their function, can be used as a cell differentiation marker and could serve as target for novel therapies

Variola virus in a 300-year-old Siberian mummy.

International audienceNo abstract available