High-Temperature Corrosion Testing of Uranium Silicide Surrogates

The corrosion resistance of cerium silicide, a surrogate of uranium silicide, is investigated to gain insight into the reaction of uranium silicide with water. As-received and proton-irradiated Ce3Si2, CeSi2, and CeSi1.x monolithic pellets are subjected to corrosion tests in water at 300°C and 9 MPa for up to 48 h. Results show that an oxide layer composed of Ce4.67 (SiO4)3O forms on the surface of all samples, and it grows thicker with extended exposure times. Irradiated samples corrode to a greater extent than their unirradiated counterparts, which is mainly a result of the existing post-irradiation cerium oxide and the presence of ion-induced defects. Most of the Ce3Si2 samples crack (as-received) or fracture (ion-irradiated) during testing, which is due to the brittleness of the samples and oxide erosion/spallation that occur during testing

Finding all maximal perfect haplotype blocks in linear time

Recent large-scale community sequencing efforts allow at an unprecedented level of detail the identification of genomic regions that show signatures of natural selection. Traditional methods for identifying such regions from individuals' haplotype data, however, require excessive computing times and therefore are not applicable to current datasets. In 2019, Cunha et al. (Advances in bioinformatics and computational biology: 11th Brazilian symposium on bioinformatics, BSB 2018, Niteroi, Brazil, October 30 - November 1, 2018, Proceedings, 2018. 10.1007/978-3-030-01722-4_3) suggested the maximal perfect haplotype block as a very simple combinatorial pattern, forming the basis of a new method to perform rapid genome-wide selection scans. The algorithm they presented for identifying these blocks, however, had a worst-case running time quadratic in the genome length. It was posed as an open problem whether an optimal, linear-time algorithm exists. In this paper we give two algorithms that achieve this time bound, one conceptually very simple one using suffix trees and a second one using the positional Burrows-Wheeler Transform, that is very efficient also in practice.Peer reviewe

Subset Wavelet Trees

Given an alphabet Σ of σ = |Σ| symbols, a degenerate (or indeterminate) string X is a sequence X = X[0],X[1]…, X[n-1] of n subsets of Σ. Since their introduction in the mid 70s, degenerate strings have been widely studied, with applications driven by their being a natural model for sequences in which there is a degree of uncertainty about the precise symbol at a given position, such as those arising in genomics and proteomics. In this paper we introduce a new data structural tool for degenerate strings, called the subset wavelet tree (SubsetWT). A SubsetWT supports two basic operations on degenerate strings: subset-rank(i,c), which returns the number of subsets up to the i-th subset in the degenerate string that contain the symbol c; and subset-select(i,c), which returns the index in the degenerate string of the i-th subset that contains symbol c. These queries are analogs of rank and select queries that have been widely studied for ordinary strings. Via experiments in a real genomics application in which degenerate strings are fundamental, we show that subset wavelet trees are practical data structures, and in particular offer an attractive space-time tradeoff. Along the way we investigate data structures for supporting (normal) rank queries on base-4 and base-3 sequences, which may be of independent interest. Our C++ implementations of the data structures are available at https://github.com/jnalanko/SubsetWT.Peer reviewe

Dynamic Micropatterning Reveals Substrate-Dependent Differences in the Geometric Control of Cell Polarization and Migration

Cells are highly dynamic and adopt variable shapes and sizes. These variations are biologically important but challenging to investigate in a spatiotemporally controlled manner. Micropatterning, confining cells on microfabricated substrates with defined geometries and molecular compositions, is a powerful tool for controlling cell shape and interactions. However, conventional binary micropatterns are static and fail to address dynamic changes in cell polarity, spreading, and migration. Here, a method for dynamic micropatterning is reported, where the non-adhesive surface surrounding adhesive micropatterns is rapidly converted to support specific cell-matrix interactions while allowing simultaneous imaging of the cells. The technique is based on ultraviolet photopatterning of biotinylated polyethylene glycol-grafted poly-L-lysine, and it is simple, inexpensive, and compatible with a wide range of streptavidin-conjugated ligands. Experiments using biotinylation-based dynamic micropatterns reveal that distinct extracellular matrix ligands and bivalent integrin-clustering antibodies support different degrees of front-rear polarity in human glioblastoma cells, which correlates to altered directionality and persistence upon release and migration on fibronectin. Unexpectedly, however, neither an asymmetric cell shape nor centrosome orientation can fully predict the future direction of migration. Taken together, biotinylation-based dynamic micropatterns allow easily accessible and highly customizable control over cell morphology and motility

Luokanopettaja oppilaan minäkuvan tukijana

Tiivistelmä. Minäkuva on käsitteenä tärkeä, koska se vaikuttaa ihmisen elämään moniulotteisesti. Tutkielman viitekehys käsittelee lapsen minäkuvaa, sen kehitystä ja tukemista. Minäkuvaan liittyvä käsitteistö on hyvin laaja, eikä sitä voi rajata ainoastaan minäkuvan käsitteeseen. Viitekehyksessä käsitellään myös käsitettä minä, jota minäkuva, identiteetti ja itsetunto siivittävät. Rajasimme minäkuvan kehityksen ja erityisesti sen tukemisen ikäluokkiin 0–12. Pro gradu -tutkielman aiheen valitsimme yhteisen kiinnostuksen pohjalta. Aihe on myös aina ajankohtainen. Yhdeksi perusopetuksen kasvatustavoitteeksi on Suomen perusopetuslain (628/1998, 4§) asetuksessa säädetty kehittää oppilaan myönteistä minäkuvaa. Opetussuunnitelman perusteissa (Opetushallitus 2004) on määritelty perusopetuksen yhdeksi tavoitteeksi antaa oppilaalle mahdollisuus myönteisen minäkuvan kehitykseen. Pro gradu -tutkimuksemme tarkoituksena oli selvittää, miten luokanopettajat määrittelevät minäkuvan käsitteen ja millaisia haasteita ja mahdollisuuksia he kokevat olevan oppilaan minäkuvan tukemisessa. Tärkeimpänä tavoitteena oli selvittää millaisia keinoja kahdella kajaanilaisella luokanopettajalla on tukea oppilaan minäkuvaa. Tutkimuksemme on luonteeltaan kvalitatiivinen tapaustutkimus ja tiedonhankinnan strategiana on käytetty fenomenografiaa. Aineisto on hankittu puolistrukturoidun teemahaastattelun, videoinnin sekä havainnoinnin avulla. Aineisto kerättiin tammikuun 2013 aikana ja tutkittavina oli kaksi kajaanilaista peruskoulun luokanopettajaa. Aineisto on analysoitu deduktiivista logiikkaa noudattaen. Tutkimustulokset osoittavat, että tutkittavat luokanopettajat ymmärtävät, mitä minäkuvalla tarkoitetaan ja he pitävät sitä merkittävänä oppilaan oppimisen kannalta. Tutkimus osoittaa, että kohdehenkilöt kokevat minäkuvan tukemisen olevan yksi oppimisen edellytyksistä. Tärkeimmäksi minäkuvan tukemisen tekijäksi tässä tutkimuksessa nousee positiivinen palaute ja sosiaalinen vuorovaikutus, jota ilman minäkuva ei pääse kehittymään. Minäkuva kehittyy sosiaalisessa vuorovaikutuksessa muiden ihmisten kanssa ja vaatii kehittyäkseen turvallisen ympäristön, joten opettajan rooli minäkuvan tukemisessa on keskeinen. Tutkimustulosten perusteella minäkuvan tukemisen haasteena ovat kasvaneet oppilasmäärät ja ajanpuute. Lisäksi luokanopettajat tiedostavat, etteivät voi yksinään vaikuttaa oppilaan minäkuvaan, vaan siihen vaikuttavat yksilön sosiaalinen ympäristö ja vanhemmat. Luokanopettajat kuitenkin kokevat, että minäkuvan tukemiselle on aikaa opettajan niin halutessaan. Luokanopettajat kertoivat käyttävänsä minäkuvan tukemisen yhtenä keinona oppilaan perusturvallisuuden lisäämistä, koska ilman sitä minäkuva ei pääse kehittymään. Ilman oppilaan perusturvallisuuden tunnetta minäkuvan tukeminen on myös haasteellisempaa. Molemmat haastateltavat korostavat sosiaalista vuorovaikutusta ja palautteen merkitystä minäkuvan tukemisessa, koska ilman sosiaalista vuorovaikutusta minäkuvaa ei voida tukea. Tutkimuksemme on hyödyllinen, koska se lisää tietoa minäkuvan merkittävyydestä ja sen tukemisen tärkeydestä. On välttämätöntä, että opettajat tiedostavat miten oppilaiden minäkuvaa tuetaan ja pyrkivät päivittäin toimimaan sen mukaisesti koulun arjessa. Tutkielmamme tarjoaa keinoja opettajille ja muille kasvattajille oppilaan minäkuvan tukemiseen

A scoping review of constructs measured following intervention for school refusal: are we measuring up?

Reviews of the effectiveness of interventions for school refusal (SR) rely upon well-conducted primary studies. Currently there are no guidelines for those conducting primary studies about the measurement of outcome following intervention for SR. Most people would agree that it is important to measure school attendance as an outcome but there has been little discussion about other constructs that warrant measurement. To facilitate this discussion and support the development of guidelines, we conducted a scoping review of constructs measured in studies evaluating intervention for SR. We screened the title and abstract of 3,213 publications found in peer-reviewed journals between 1980 and 2019. After full text review of 271 publications, 50 publications describing 51 studies were included. Results address the frequency with which constructs were measured, along with instruments used, informants, and time-points for measurement. Based on the results, we offer guidelines for choosing constructs to measure following intervention for SR and considerations for how to measure the constructs. Guidelines can increase consistency across primary studies, with benefits for future meta-analyses and international comparisons. They also provide support for practitioners contemplating routine evaluation of their interventions for SR. Ultimately, a core outcome set for SR can be developed.Pathways through Adolescenc

Follow-Up of Cancer Patients Receiving Anti-PD-(L)1 Therapy Using an Electronic Patient-Reported Outcomes Tool (KISS): Prospective Feasibility Cohort Study

Background: Immune checkpoint inhibitors (ICIs) have become a standard of care for various tumor types. Their unique spectrum of side effects demands continuous and long-lasting assessment of symptoms. Electronic patient-reported outcome (ePRO) follow-up has been shown to improve survival and quality of life of cancer patients treated with chemotherapy.Objective: This study aimed to investigate whether ePRO follow-up of cancer patients treated with ICIs is feasible. The study analyzed (1) the variety of patient reported symptoms, (2) etiology of alerts, (3) symptom correlations, and (4) patient compliance.Methods: In this prospective, one-arm, multi-institutional study, we recruited adult cancer patients whose advanced cancer was treated with anti-programmed cell death protein 1 (PD)-ligand (L)1 agents in outpatient settings. The ePRO tool consisted of a weekly questionnaire evaluating the presence of typical side effects, with an algorithm assessing the severity of the symptom according to National Cancer Institute Common Terminology Criteria for Adverse Events and an urgency algorithm sending alerts to the care team. A patient experience survey was conducted monthly. The patients were followed up to 6 months or until disease progression.Results: A total of 889 symptom questionnaires was completed by 37 patients (lung cancer, n=15; melanoma, n=9; genitourinary cancer, n=9; head and neck cancer, n=4). Patients showed good adherence to ePRO follow-up. The most common grade 1 symptoms were fatigue (28%) and itching (13%), grade 2 symptoms were loss of appetite (12%) and nausea (12%), and grade 3-4 symptoms were cough (6%) and loss of appetite (4%). The most common reasons for alerts were loss of appetite and shortness of breath. In the treatment benefit analysis, positive correlations were seen between clinical benefit and itching as well as progressive disease and chest pain.Conclusions: According to the results, ePRO follow-up of cancer patients receiving ICIs is feasible. ePROs capture a wide range of symptoms. Some symptoms correlate to treatment benefit, suggesting that individual prediction models could be generated

Integrin endosomal signalling suppresses anoikis

Integrin-containing focal adhesions transmit extracellular signals across the plasma membrane to modulate cell adhesion, signalling and survival. Although integrins are known to undergo continuous endo/exocytic traffic, the potential impact of endocytic traffic on integrin-induced signals is unknown. Here, we demonstrate that integrin signalling is not restricted to cell-ECM adhesions and identify an endosomal signalling platform that supports integrin signalling away from the plasma membrane. We show that active focal adhesion kinase (FAK), an established marker of integrin-ECM downstream signalling, localizes with active integrins on endosomes. Integrin endocytosis positively regulates adhesion-induced FAK activation, which is early endosome antigen-1 and small GTPase Rab21 dependent. FAK binds directly to purified endosomes and becomes activated on them, suggesting a role for endocytosis in enhancing distinct integrin downstream signalling events. Finally, endosomal integrin signalling contributes to cancer-related processes such as anoikis resistance, anchorage independence and metastasis.</p