26 research outputs found
Seeing infants and toddlers as heilala (high-ranking flowers): A Tongan perspective
No full textHau’ofa’s (1994) words remind us that Pacific children enter our early
childhood settings already connected and whole. Dr Jeanne Teisina
(Hofoa, Vava’u), Tongan centre leader and co-researcher on our
TLRI project exploring Pacific leadership in ECE, showed this during
our interview talanoa (open talk) by describing infants and toddlers
in her centre as heilala (a high-ranking flower in the Tongan culture),
treasured and nestled within their families, languages, cultures,
and places. What follows brings Jeanne’s insights and my (Maria)
reflections forward, organised by themes that arose during our talanoa. We provide simple English translations for the Tongan terms but acknowledge that their underlying meaning may not be fully conveyed in the English translation. This move allows us to uphold the integrity of the Tongan language while making it accessible to a broader audience
Fibriinihydrogeelit rintasyöpäsolujen kolmiulotteisen viljelyn tukirankana
No full textDespite the advances in the management of breast cancer, discovery of novel and targeted drugs remains a challenge. It has been suggested that drug failure rates in clinical trials might be diminished by improving the predictive potential of preclinical cancer models. Three-dimensional (3D) scaffold-based cell culture has emerged as an attractive platform for mimicking tissue-like microenvironment, since it is well-known that cells respond to the cues in the extracellular matrix (ECM). The aim of this thesis was to develop fibrin-based hydrogels and evaluate their performance in 3D cell culture of breast cancer cells.
The fibrin gel formulation was first optimized by testing the effect of different buffers on gel properties. Structural properties were examined with scanning electron microscopy and mechanical properties measured with oscillatory rheometry. Three different fibrin concentrations of the optimized formulation were then used as scaffolds for DU4475 breast cancer cells. After seven days of culture, the morphology, phenotype and proliferation of the resulting cell structures were assessed by using techniques such as light microscopy, immunofluorescent confocal microscopy and Western blot analysis.
The desired properties for 3D cell culture were obtained by preparing fibrin gels at high pH in the absence of calcium. The main finding of the thesis was that fibrin concentration strongly affected the phenotype of DU4475 cells, with cells cultured in the softest gel retaining their original characteristics to the greatest extent. In the future, the developed scaffold could possibly be used in drug discovery and personalized medicine by culturing tumor explants from patients. However, the methods used in the study must be further optimized and the results validated with other breast cancer cell lines and with primary tissues
Hybrid Decision Support and Justification Methods for Production System Selection
No full textThis article presents different decision support and justification method principles for production system selection and development. The focus is on analytic approaches, discrete event simulation, queue theories and linear programming. Other approaches, both strategic and economic, are simply listed but are nonetheless of major importance. The benefits of discrete event simulation are discussed, along with reasons for not using it. Analytic methods, queue theories, linear programming, i.e. optimisation, are useful and can be used before or parallel to simulation modelling. The use of different methods is compared and a combination of different methods, i.e. hybrid methods, is discussed. The author proposes the use of hybrid methods and different types of modelling and simulation in production system concept creation and selection. The article is based on the author's experience of assembly system design and on a literature study
Kansanvalistusseuran kalenteri 1912 : kolmaskymmenestoinen vuosikerta
No full textVuosi 1912 – Merkkien ja lyhennysten selityksiä
Almanakka (12 vign.) muistiinpanolehtineen. Muisto- ja merkkipäiviä y. m. – Viivan alla: Maamiehen vuosi, kirj. E. Hirvelä
Toripäivät, joita pidetään useammin vuodessa
Keisarillinen perhe (vign.) – Keisarilliset juhlapäivät
Maailman valtioitten päämiehiä (vign.)
Suomen virastoja ja virkamiehiä
Metrijärjestelmä
Eri maiden rahat, mitat ja painot
Postimaksut
Tietoja rautateistä
Sähkösanomista
Leimasuostunta (ynnä perintövero)
Viipurin lääni 1811–1911, kirj. Antti Komonen (2 vign. ja 14 kuv.)
Kansallisen yliopiston perustaminen (2 vign.). Tiedustelu, johon omat vastauksia antaneet P. Ahmavaara, J. R. Danielson-Kalmari, Hannes Gebhard, A. A. Granfelt, Arvi Grotenfelt, O. Hannikainen, K. J. Jalkanen, Johannes Linnakoski, W. Malinen, Yrjö Mäkelin, Alpo Noponen, E. G. Palmén, E. N. Setälä ja Y. K. Yrjö-Koskinen
Maamme keskushallinto sata vuotta sitten, kirj. K. W. Rauhala (3 vign.)
Piirteitä Ida Aalbergin lapsuudesta, kirj. Maila Talvio (2 vign. ja 4 kuv.)
Kauppis-Heikki, Santeri Alkio ja Kalle Kajander 50-vuotiaina, kirj. W. Tarkiainen (6 vign. ja 3 kuv.)
Suomen rautateitten viisikymmenvuotinen muisto, kirj. E. G. Palmén
Piirteitä Aunuksen Karjalasta, kirj. Väinö Salminen (2 vign. ja 10 kuv.)
Talvisella tiellä. Runo, kirj. i-aa
Urheiluriennoista Suomessa, kirj. Lauri Pihkala (2 vign. ja 7 kuv.)
Elämän sisältö, kirj. Maria Jotuni (2 vign. ja 2 kuv.)
Mainen onni, kirj. Yrjö Heilala (3 vign. ja 2 kuv.)
Rehunpuutteen aikana, kirj. Alpo Noponen (2 vign. ja 3 kuv.)
Kellertävät vainiot. Runo, kirj. Lauri Kemiläinen
Rutosta, kirj. Armas Ruotsalainen (2 vign. ja 3 kuv.)
Nykyaikainen käsitys uusien lajien syntymisestä, kirj. Einar Fieandt (2 vign. ja 8 kuv.)
Italian vapaustaistelu ja sen seuraukset, kirj. Liisi Karttunen (3 vign. ja 8 kuv.)
Uudesta kirkkokäsikirjaehdotuksesta muutama sana, kirj. Yrjö Loimaranta (3 vign.)
Valtiopäivät (2 wign.)
Neljäs valtiopäiväkausi: 1910, kirj. J. A.
Viides valtiopäiväkausi: 1911, kirj. J. D. Lilius
Silmäys kuluneen vuoden vaiheisiin, kirj. V. V. (2 vign. ja 11 kuv.)
Muistosanoja vainajille, kirj. V. H. (2 vign. ja 5 kuv.)
Uusi päivä. Runo, kirj. Lauri Kemiläinen
Sodasta ja rauhanajasta, kirj. Kyösti H-la (2 vign.)
Karjalan laulu. Runo, kirj. Eero Eerola (2 kuv.).ei tietoa saavutettavuudest
Magnetic microrheometry of tumor-relevant stiffness levels and probabilistic quantification of viscoelasticity differences inside 3D cell culture matrices.
No full textThe progression of breast cancer involves cancer-cell invasions of extracellular matrices. To investigate the progression, 3D cell cultures are widely used along with different types of matrices. Currently, the matrices are often characterized using parallel-plate rheometry for matrix viscoelasticity, or liquid-like viscous and stiffness-related elastic characteristics. The characterization reveals averaged information and sample-to-sample variation, yet, it neglects internal heterogeneity within matrices, experienced by cancer cells in 3D culture. Techniques using optical tweezers and magnetic microrheometry have measured heterogeneity in viscoelasticity in 3D culture. However, there is a lack of probabilistic heterogeneity quantification and cell-size-relevant, microscale-viscoelasticity measurements at breast-tumor tissue stiffness up to ≃10 kPa in Young's modulus. Here, we have advanced methods, for the purpose, which use a magnetic microrheometer that applies forces on magnetic spheres within matrices, and detects the spheres displacements. We present probabilistic heterogeneity quantification using microscale-viscoelasticity measurements in 3D culture matrices at breast-tumor-relevant stiffness levels. Bayesian multilevel modeling was employed to distinguish heterogeneity in viscoelasticity from the effects of experimental design and measurement errors. We report about the heterogeneity of breast-tumor-relevant agarose, GrowDex, GrowDex-collagen and fibrin matrices. The degree of heterogeneity differs for stiffness, and phase angle (i.e. ratio between viscous and elastic characteristics). Concerning stiffness, agarose and GrowDex show the lowest and highest heterogeneity, respectively. Concerning phase angle, fibrin and GrowDex-collagen present the lowest and the highest heterogeneity, respectively. While this heterogeneity information involves softer matrices, probed by ≃30 μm magnetic spheres, we employ larger ≃100 μm spheres to increase magnetic forces and acquire a sufficient displacement signal-to-noise ratio in stiffer matrices. Thus, we show pointwise microscale viscoelasticity measurements within agarose matrices up to Young's moduli of 10 kPa. These results establish methods that combine magnetic microrheometry and Bayesian multilevel modeling for enhanced heterogeneity analysis within 3D culture matrices
Fibrin Stiffness Regulates Phenotypic Plasticity of Metastatic Breast Cancer Cells
No full textThe extracellular matrix (ECM)-regulated phenotypic plasticity is crucial for metastatic progression of triple negative breast cancer (TNBC). While ECM faithful cell-based models are available for in situ and invasive tumors, such as cell aggregate cultures in reconstituted basement membrane and in collagenous gels, there are no ECM faithful models for metastatic circulating tumor cells (CTCs). Such models are essential to represent the stage of metastasis where clinical relevance and therapeutic opportunities are significant. Here, CTC-like DU4475 TNBC cells are cultured in mechanically tunable 3D fibrin hydrogels. This is motivated, as in circulation fibrin aids CTC survival by forming a protective coating reducing shear stress and immune cell-mediated cytotoxicity and promotes several stages of late metastatic processes at the interface between circulation and tissue. This work shows that fibrin hydrogels support DU4475 cell growth, resulting in spheroid formation. Furthermore, increasing fibrin stiffness from 57 to 175 Pa leads to highly motile, actin and tubulin containing cellular protrusions, which are associated with specific cell morphology and gene expression patterns that markedly differ from basement membrane or suspension cultures. Thus, mechanically tunable fibrin gels reveal specific matrix-based regulation of TNBC cell phenotype and offer scaffolds for CTC-like cells with better mechano-biological properties than liquid.3D fibrin gels are used to model the phenotypic plasticity of circulating tumor cells (CTCs) -like breast cancer cells. Compared with standard 3D culture conditions, cells in fibrin gels show unique gene expression signatures. The cell phenotype is subject to regulation by matrix mechanical properties, with stiff fibrin inducing dynamic cell protrusions that resemble prometastatic structures.imagePeer reviewe
Supporting information contains all the supporting tables, figures and calculations.
No full textSupporting information contains all the supporting tables, figures and calculations.</p
Microrheometry for the viscoelasticity of the matrix types.
No full textMicrorheometry for the viscoelasticity of the matrix types.</p
Heterogeneity model definition for quantifying spatial variation of viscoelastic parameters in 3D culture matrices.
No full textThe mean value of each magnetic sphere is estimated as a sum of multiple level effects. There are m different matrix materials, h holders, s samples, h magnetic beads, and r repeats. Different 3D matrix material types are independent of each other, apart from sharing a common mean noise term. Partial pooling is used for each level of hierarchy to improve robustness. Specific level effects are denoted by a parameter vector μ, where the superscript is the level, and the subscript is the parameter corresponding the given observation (m, h, s, or t). The scale of the effect is provided by α with analogous super/subscripts. Non-centered parametrization is used for the level effects that are denoted using dotted lines (Eq 14). This model is run separately for estimating the absolute shear modulus (|G|) and the phase angle (ϕ) (denoted by y with subscripts). The gray color indicates observations (i.e. either |G|, or ϕ). The used data has been z-score normalized.</p
Work demands and work resources : Testing a model of factors predicting turnover intentions in early childhood education
No full textWe studied the working conditions in Early Childhood Education and Care (ECEC). The aim was to explore how ECEC staff experience work demands and resources and how these relate to turnover intentions. The research was based on a modified Job Demands-Resources model (Bakker and Demerouti in J Manage Psychol 22(3):309-328, 2007) according to which job strain is influenced by both job demands and resources. The sample was identified through trade union registers and the data were collected via a survey (N = 538). The findings show a rather high proportion of turnover intentions. Both general workload and emotional workload were related to turnover intentions, and they were mediated by participation. However, leadership satisfaction did not mediate the relationship between workload and turnover intentions. This study contributes to the knowledge on risk factors related to intentions to leave the ECEC profession in the Finnish as well as the international context. It is urgent to know more about factors related to turnover because a high rate undermines trust in the ECEC sector and negatively impacts staff and children.Peer reviewe
