University of Oulu
  • Oulu, Finland
Recent publications
Production scheduling is the central link between enterprise production and operation management and is also the key to realising efficient, high-quality and sustainable production. However, in real-world manufacturing, the frequent occurrence of abnormal disturbance leads to the deviation of scheduling, which affects the accuracy and reliability of scheduling execution. The traditional dynamic scheduling methods (TDSMs) cannot solve this problem effectively. This paper presents a real-time digital twin flexible job shop scheduling (R-DTFJSS) method with edge computing to address the issue. Firstly, an overall framework of R-DTFJSS is proposed to realise real-time scheduling (RS) through real-time interaction between physical workshop (PW) and virtual workshop (VW). Secondly, the implementation process of R-DTFJSS is designed to realise real-time operation allocation. Then, to obtain the optimal RS result, an improved Hungarian algorithm (IHA) is adopted. Finally, a case simulation from an industrial case of a cooperative enterprise is described and analysed to verify the effectiveness of the proposed R-DTFJSS method. The results show that compared with the TDSMs, the R-DTFJSS method can effectively deal with unexpected and frequent abnormal disturbances in the production process.
Background Genome-wide association studies (GWAS) have identified multiple common breast cancer susceptibility variants. Many of these variants have differential associations by estrogen receptor (ER) status, but how these variants relate with other tumor features and intrinsic molecular subtypes is unclear. Methods Among 106,571 invasive breast cancer cases and 95,762 controls of European ancestry with data on 173 breast cancer variants identified in previous GWAS, we used novel two-stage polytomous logistic regression models to evaluate variants in relation to multiple tumor features (ER, progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2) and grade) adjusting for each other, and to intrinsic-like subtypes. Results Eighty-five of 173 variants were associated with at least one tumor feature (false discovery rate < 5%), most commonly ER and grade, followed by PR and HER2. Models for intrinsic-like subtypes found nearly all of these variants (83 of 85) associated at p < 0.05 with risk for at least one luminal-like subtype, and approximately half (41 of 85) of the variants were associated with risk of at least one non-luminal subtype, including 32 variants associated with triple-negative (TN) disease. Ten variants were associated with risk of all subtypes in different magnitude. Five variants were associated with risk of luminal A-like and TN subtypes in opposite directions. Conclusion This report demonstrates a high level of complexity in the etiology heterogeneity of breast cancer susceptibility variants and can inform investigations of subtype-specific risk prediction.
Very low frequency wave intensity variations measured by the Kannuslehto station, Finland in the frequency range 0–12 kHz between 2016 and 2020 are analyzed by the principal component analysis (PCA). As the analyzed ground-based measurements are basically continuous, the length of individual basis vectors entering into PCA is fundamentally arbitrary. To better characterize both long- and short-period variations, two PCAs with different lengths of the basis vectors are eventually performed. Specifically, either daily frequency–time spectrograms or individual frequency spectra are chosen as the PCA basis vectors. Analysis of the first three principal components shows substantial variations of the wave intensity due to seasonal and local time effects. Intensity variations related to the geomagnetic activity characterized by Kp and AE indices and standard deviation of the magnetic field magnitude are less significant. Moreover, PCA allows one to distinguish between nighttime and daytime Kannuslehto variations and study them independently. Solar and geomagnetic activity effects on the daytime and nighttime measurements are discussed. Wave intensity variations related to substorm occurrence are also analyzed. Graphic Abstract
Data from three all-sky cameras in Kiruna and Tjautjas (Sweden) were used to estimate the altitude of pulsating arc-like forms using optical tomography. The event under consideration occurred during the substorm recovery phase and comprised both periodic luminosity variation of the on/off type with repetition periods of 3–6 s (main pulsations) and faster scintillation (approximately 2 Hz) during the “on” phase of the main pulsations. It is found that (1) the altitudes of the pulsating auroral arcs decrease during “on” intervals from ~ 95 km to ~ 92 km and (2) for two closely spaced arcs, internal modulation took place only in the lowest arc. The results may be interpreted in the frame of the traditional mechanism assuming electron scattering via VLF-wave/particle interaction in the equatorial magnetosphere, while the internal modulation may also be alternatively interpreted in the frame of the less-often inferred mechanism of field-aligned acceleration somewhere between the equatorial plane and ionosphere. Graphical Abstract
Background Prehospital medical problem reporting is essential in the management of helicopter emergency medical services (HEMS) operations. The consensus-based template for reporting and documenting in physician-staffed prehospital services exists and the classification of medical problems presented in the template is widely used in research and quality improvement. However, validation of the reported prehospital medical problem is lacking. This study aimed to describe the in-hospital diagnoses, patient characteristics and medical interventions in different categories of medical problems. Methods This retrospective, observational registry study examined the 10 most common in-hospital International Statistical Classification of Disease (ICD-10) diagnoseswithin different prehospital medical problem categories, defined by the HEMS physician/paramedic immediately after the mission was completed. Data were gathered from a national HEMS quality registry and a national hospital discharge registry. Patient characteristics and medical interventions related to different medical problem categories are also described. Results A total of 33,844 patients were included in the analyses. All the medical problem categories included a broad spectrum of ICD-10 diagnoses (the number of diagnosis classes per medical problem category ranged from 73 to 403). The most frequent diagnoses were mainly consistent with the reported medical problems. Overlapping of ICD-10 diagnoses was mostly seen in two medical problem categories: stroke and acute neurology excluding stroke. Additionally, typical patient characteristics and disturbances in vital signs were related to adequate medical problem categories. Conclusions Medical problems reported by HEMS personnel have adequate correspondence to hospital discharge diagnoses. However, the classification of cerebrovascular accidents remains challenging.
It is well known that green urban commons enhance mental and physical well-being and improve local biodiversity. We aim to investigate how these outcomes are related in an urban system and which variables are associated with better outcomes. We model the outcomes of an urban common—box gardening—by applying the Social-Ecological Systems (SES) framework. We expand the SES framework by analyzing it from the perspective of social evolution theory. The system was studied empirically through field inventories and questionnaires and modeled quantitatively by Structural Equation Modeling (SEM). This method offers powerful statistical models of complex social-ecological systems. Our results show that objectively evaluated ecological outcomes and self-perceived outcomes are decoupled: gardening groups that successfully govern the natural resource ecologically do not necessarily report many social, ecological, or individual benefits, and vice versa. Social capital, box location, gardener concerns, and starting year influenced the changes in the outcomes. In addition, the positive association of frequent interactions with higher self-perceived outcomes, and lack of such association with relatedness of group members suggests that reciprocity rather than kin selection explains cooperation. Our findings exemplify the importance of understanding natural resource systems at a very low “grassroot” level.
Background Von Hippel-Lindau (VHL) disease is an autosomal dominant genetic neoplastic disorder caused by germline mutation or deletion of the VHL gene, characterized by the tendency to develop multisystem benign or malignant tumors. The mechanism of VHL mutants in pathogenicity is poorly understand. Results Here we identified heterozygous missense mutations c.193T > C and c.194C > G in VHL in several patients from two Chinese families. These mutations are predicted to cause Serine (c.193T > C) to Proline and Tryptophan (c.194C > G) substitution at residue 65 of VHL protein (p.Ser65Pro and Ser65Trp). Ser65 residue, located within the β-domain and nearby the interaction sites with hypoxia-inducing factor α (HIFα), is highly conserved among different species. We observed gain of functions in VHL mutations, thereby stabilizing HIF2α protein and reprograming HIF2α genome-wide target gene transcriptional programs. Further analysis of independent cohorts of patients with renal carcinoma revealed specific HIF2α gene expression signatures in the context of VHL Ser65Pro or Ser65Trp mutation, showing high correlations with hypoxia and epithelial-mesenchymal transition signaling activities and strong associations with poor prognosis. Conclusions Together, our findings highlight the crucial role of pVHL-HIF dysregulation in VHL disease and strengthen the clinical relevance and significance of the missense mutations of Ser65 residue in pVHL in the familial VHL disease.
We trace the evolution of research on extreme solar and solar-terrestrial events from the 1859 Carrington event to the rapid development of the last twenty years. Our focus is on the largest observed/inferred/theoretical cases of sunspot groups, flares on the Sun and Sun-like stars, coronal mass ejections, solar proton events, and geomagnetic storms. The reviewed studies are based on modern observations, historical or long-term data including the auroral and cosmogenic radionuclide record, and Kepler observations of Sun-like stars. We compile a table of 100- and 1000-year events based on occurrence frequency distributions for the space weather phenomena listed above. Questions considered include the Sun-like nature of superflare stars and the existence of impactful but unpredictable solar "black swans" and extreme "dragon king" solar phenomena that can involve different physics from that operating in events which are merely large.
Synthesis is the base of experimental chemistry. Herein, monodisperse K3PMo12O40▪nH2O polyoxometalates (POMs) with different morphologies have been reached by tuning synthetic conditions of the K/POM ratio, stirring speed and time, and reaction temperatures. Among these factors, the K/POM ratio is identified most critical in morphological controls of the K3PMo12O40▪nH2O particles, altering them from cubes to spheres. Additionally, morphological transformations were identified through a self-assembly and Ostwald ripening process, setting a generic synthetic strategy for the POM systems. Such synthetic strategies have substantial applications in catalytic or surface-demanding fields requiring POM materials with controlled morphology.
Background Parkinson’s disease (PD) is genetically associated with the H1 haplotype of the MAPT 17q.21.31 locus, although the causal gene and variants underlying this association have not been identified. Methods To better understand the genetic contribution of this region to PD and to identify novel mechanisms conferring risk for the disease, we fine-mapped the 17q21.31 locus by constructing discrete haplotype blocks from genetic data. We used digital PCR to assess copy number variation associated with PD-associated blocks, and used human brain postmortem RNA-seq data to identify candidate genes that were then further investigated using in vitro models and human brain tissue. Results We identified three novel H1 sub-haplotype blocks across the 17q21.31 locus associated with PD risk. Protective sub-haplotypes were associated with increased LRRC37A/2 copy number and expression in human brain tissue. We found that LRRC37A/2 is a membrane-associated protein that plays a role in cellular migration, chemotaxis and astroglial inflammation. In human substantia nigra, LRRC37A/2 was primarily expressed in astrocytes, interacted directly with soluble α-synuclein, and co-localized with Lewy bodies in PD brain tissue. Conclusion These data indicate that a novel candidate gene, LRRC37A/2 , contributes to the association between the 17q21.31 locus and PD via its interaction with α-synuclein and its effects on astrocytic function and inflammatory response . These data are the first to associate the genetic association at the 17q21.31 locus with PD pathology, and highlight the importance of variation at the 17q21.31 locus in the regulation of multiple genes other than MAPT and KANSL1 , as well as its relevance to non-neuronal cell types.
Context Tangled commits are changes to software that address multiple concerns at once. For researchers interested in bugs, tangled commits mean that they actually study not only bugs, but also other concerns irrelevant for the study of bugs. Objective We want to improve our understanding of the prevalence of tangling and the types of changes that are tangled within bug fixing commits. Methods We use a crowd sourcing approach for manual labeling to validate which changes contribute to bug fixes for each line in bug fixing commits. Each line is labeled by four participants. If at least three participants agree on the same label, we have consensus. Results We estimate that between 17% and 32% of all changes in bug fixing commits modify the source code to fix the underlying problem. However, when we only consider changes to the production code files this ratio increases to 66% to 87%. We find that about 11% of lines are hard to label leading to active disagreements between participants. Due to confirmed tangling and the uncertainty in our data, we estimate that 3% to 47% of data is noisy without manual untangling, depending on the use case. Conclusion Tangled commits have a high prevalence in bug fixes and can lead to a large amount of noise in the data. Prior research indicates that this noise may alter results. As researchers, we should be skeptics and assume that unvalidated data is likely very noisy, until proven otherwise.
The aim of the current study was to examine the associations of dispositional optimism and pessimism with cognitive abilities in adulthood. We performed two studies with data sets from the prospective Northern Finland Birth Cohort Studies: 26-year-olds (N = 383) and 46-year-olds (N = 5042). In both samples, dispositional optimism and pessimism were measured with Carver and Scheier's Life Orientation Test -Revised. In the data of 26-year-olds, the cognitive abilities assessed were reasoning, vocabulary, verbal fluency, fine-motor skills, selective attention, impulse control, and memory, while in 46-year-olds, memory was assessed. The analyses were carried out using multiple linear regression, and the associations were adjusted for gender, educational level, mother's educational level, and depression. Our results indicated that (I.) higher dispositional optimism and lower pessimism were associated with higher reasoning skills in young adults, and (II.) higher pessimism was related to lower scores on memory test in middle-aged adults. The findings provide a closer look on how dispositional optimism and pessimism are associated with the core cognitive abilities in adults.
The process through which social impact occurs in business relationships has largely remained unexamined. In this paper, we draw on relational contracting theory to examine relationship norms and the social impact of their legitimation. Our data consist of 27 years of historical secondary data about the business relationship between Nokia and its subcontracting partner Elcoteq (1984–2011). We reveal how the legitimation of the role integrity and contractual solidarity norms causes social impact within this relationship and how harmonization with the social matrix norm leads to social impact both within and outside of the relationship. As a result, we introduce a concept network view of social impact. This concept thus contributes to the business relationship literature by conceptualizing the ripple effect of one business relationship on a connected network.
Proper management and storage of mine waste, e.g., tailings and waste rock, is one of the main issues that mining industries face. Additionally, there is already an uncountable amount of existent historical mine waste, which may, even centuries after the closure of the mine, still be leaching contaminants into the environment. One solution to minimize the risks associated with the mine waste, with also potential economic benefits, is through the valorization of the waste. This can be done by first recovering valuable metals and removing hazardous contaminants. Then, the remaining residue can be valorized into green construction materials, such as geopolymers, ceramics or cement. For some mine waste materials, such as those with only trace levels of metals that are not economically viable to extract, the “waste” can be reused directly without this additional cleaning step. In the present study, mine waste originating from three different sites was characterized and compared with the cleaned mine waste (i.e., cleaned by bioleaching or flotation methods) and with different types of green construction materials containing 13–80 wt% (cleaned and uncleaned) mine waste. Particular emphasis was given to the mobilization of metal(loid)s from the mine waste and construction materials (i.e., ceramics, alkali-activated materials and cement) under different conditions, through a series of leaching tests (i.e., EN 12457–2, US EPA's Toxicity Characteristic Leaching Procedure, and a pH-dependent leaching test). The leaching tests were applied to either mimic current ‘natural’ conditions at the mining site, conditions in a landfill (end of life) or extreme conditions (i.e., extremely acidic or alkaline pH). Most of the original mine waste samples contain high levels of Pb (18–3160 mg/kg), Zn (66–10500 mg/kg), and As (10–4620 mg/kg). . The cleaning methods were not always efficient in removing the metal(loid)s and sulfur. In some cases, the cleaned mine waste samples even contained higher total metal(loid) and sulfur concentrations than the original mine waste samples. Based on the leaching studies, some alkali-activated materials, ceramics, and cement effectively immobilized certain metals (e.g., <0.5 mg/kg of Pb and <4 mg/kg of Zn). Also, longer curing times of the alkali-activated materials, in most cases, improved the immobilization of metal(loid)s. Additionally, for ceramics, the temperature at which the test pieces were fired (up to 1060 °C), also played a major role in decreasing the mobility of some metal(loid)s, while increasing others (e.g., As, potentially via the structural rearrangement of As and Fe). Overall, through this detailed characterization, the environmental impact from the mine waste to the downstream products was evaluated, determining which valorization methods are the most viable to close the circular economy loop.
Let G(d,n) be the Grassmannian manifold of n-dimensional subspaces of Rd, and let πV:Rd→V be the orthogonal projection. We prove that if μ is a compactly supported Radon measure on Rd satisfying the s-dimensional Frostman condition μ(B(x,r))⩽Crs for all x∈Rd and r>0, then∫G(d,n)‖πVμ‖Lp(V)pdγd,n(V)<∞,1⩽p<2d−n−sd−s. The upper bound for p is sharp, at least, for d−1⩽s⩽d, and every 0<n<d. Our motivation for this question comes from finding improved lower bounds on the Hausdorff dimension of (s,t)-Furstenberg sets. For 0⩽s⩽1 and 0⩽t⩽2, a set K⊂R2 is called an (s,t)-Furstenberg set if there exists a t-dimensional family L of affine lines in R2 such that dimH⁡(K∩ℓ)⩾s for all ℓ∈L. As a consequence of our projection theorem in R2, we show that every (s,t)-Furstenberg set K⊂R2 with 1<t⩽2 satisfiesdimH⁡K⩾2s+(1−s)(t−1). This improves on previous bounds for pairs (s,t) with s>12 and t⩾1+ϵ for a small absolute constant ϵ>0. We also prove a higher dimensional analogue of this estimate for codimension-1 Furstenberg sets in Rd. As another corollary of our method, we obtain a δ-discretised sum-product estimate for (δ,s)-sets. Our bound improves on a previous estimate of Chen for every 12<s<1, and also of Guth-Katz-Zahl for s⩾0.5151.
Characterizing and understanding the mechanisms underlying geopolymerization are critical in achieving the use of sustainable construction material, geopolymer, for widespread commercial production. Non-destructive ¹H NMR relaxometry can provide novel information about geopolymerization as it allows simultaneous detection of where the water goes and how the pore structure changes. Coupled with the development of single-sided NMR devices, NMR measurements are not limited by the specimen size and are therefore able to observe in-situ conditions of geopolymer synthesis. Here, the curing process of metakaolin-based geopolymers was monitored by ¹H relaxometry on a single-sided NMR device. The silica-to-alumina ratio (Si/Al) was found to affect reaction stages of the geopolymerization. After the dissolution of aluminosilicate precursor, the low Si/Al of 1 was found to generate three gelation/polymerization stages as well as a water-binding stage, and two gel phases appeared. When Si/Al varied in 1.5–2.5, two gelation/polymerization stages and only one gel phase was observed.
Sedimentation has a prominent impact on the functionality and lifetime of reservoirs and is a growing concern for stakeholders. Various parameters influence sedimentation caused by soil erosion. Here we have examined fifty Italian reservoirs to determine sedimentation rates and storage capacity loss. The reservoirs studied have an average age of 78 years as of 2021, with the highest loss of capacity observed, equal to 100%, for Ceppo Morelli. For the fifty Italian catchments covering north, south, central and islands of Italy, we found the mean annual sediment yield varying between 17–4000 m³/km². year. Six of fifty reservoirs studied (Quarto, Colombara, Ceppo Morelli, Fusino, Vodo and Valle di Cadore) are already in a very critical situation in terms of storage capacity loss. Out of the fifty reservoirs, half of them will reach their half-life year by 2050. For example, for the Fusino reservoir located in northern Italy, we observed a loss of 90% of the storage volume as of 2020 with respect to its operation year 1974, compared to 6% in 2015 as available in literature. Modelling the sediment delivery ratio (SDR) is an open question, due to the lack of adequate data and uncertainties about the variability in hydrological, geomorphological, climate and landcover parameters. Here, we addressed the issue with a simplified multiple regression approach based on sediment delivery ratio values retrieved by the RUSLE model. We found different multi regressions for reservoirs belonging to the Alpine and Apennine regions. This analysis offers a starting point for the management and prioritization of adaptation and remediation policies necessary to address reservoir sedimentation.
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Leila Risteli
  • Institute of Diagnostics
Ibrahim Mahjneh
  • Department of Neurology
Shivaprakash Jagalur Mutt
  • Department of Physiology
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