Browsing by Subject "PATTERN"

Sort by: Order: Results:

Now showing items 1-20 of 24
  • Radhakrishnan, Dhanya; Shanmukhan, Anju Pallipurath; Kareem, Abdul; Aiyaz, Mohammed; Varapparambathu, Vijina; Toms, Ashna; Kerstens, Merijn; Valsakumar, Devisree; Landge, Amit N.; Shaji, Anil; Mathew, Mathew K.; Sawchuk, Megan G.; Scarpella, Enrico; Krizek, Beth A.; Efroni, Idan; Mähönen, Ari Pekka; Willemsen, Viola; Scheres, Ben; Prasad, Kalika (2020)
    Aerial organs of plants, being highly prone to local injuries, require tissue restoration to ensure their survival. However, knowledge of the underlying mechanism is sparse. In this study, we mimicked natural injuries in growing leaves and stems to study the reunion between mechanically disconnected tissues. We show that PLETHORA (PLT) and AINTEGUMENTA (ANT) genes, which encode stem cell-promoting factors, are activated and contribute to vascular regeneration in response to these injuries. PLT proteins bind to and activate the CUC2 promoter. PLT proteins and CUC2 regulate the transcription of the local auxin biosynthesis gene YUC4 in a coherent feed-forward loop, and this process is necessary to drive vascular regeneration. In the absence of this PLT-mediated regeneration response, leaf ground tissue cells can neither acquire the early vascular identity marker ATHB8, nor properly polarise auxin transporters to specify new venation paths. The PLT-CUC2 module is required for vascular regeneration, but is dispensable for midvein formation in leaves. We reveal the mechanisms of vascular regeneration in plants and distinguish between the wound-repair ability of the tissue and its formation during normal development.
  • Raerinne, Jani (2018)
    In addition to their core explanatory and predictive assumptions, scientific models include simplifying assumptions, which function as idealizations, approximations, and abstractions. There are methods to investigate whether simplifying assumptions bias the results of models, such as robustness analyses. However, the equally important issue - the focus of this paper - has received less attention, namely, what are the methodological and epistemic strengths and limitations associated with different simplifying assumptions. I concentrate on one type of simplifying assumption, the use of mega parameters as abstractions in ecological models. First, I argue that there are two kinds of mega parameters qua abstractions, sufficient parameters and aggregative parameters, which have gone unnoticed in the literature. The two are associated with different heuristics, holism and reductionism, which many view as incompatible. Second, I will provide a different analysis of abstractions and the associated heuristics than previous authors. Reductionism and holism and the accompanying abstractions have different methodological and epistemic functions, strengths, and limitations, and the heuristics should be viewed as providing complementary research perspectives of cognitively limited beings. This is then, third, used as a premise to argue for epistemic and methodological pluralism in theoretical ecology. Finally, the presented taxonomy of abstractions is used to comment on the current debate whether mechanistic accounts of explanation are compatible with the use of abstractions. This debate has suffered from an abstract discussion of abstractions. With a better taxonomy of abstractions the debate can be resolved.
  • Price, D.; Tyler, L. K.; Henriques, R. Neto; Campbell, K. L.; Williams, N.; Treder, M. S.; Taylor, J. R.; Henson, R. N. A.; Cam-CAN (2017)
    Slowing is a common feature of ageing, yet a direct relationship between neural slowing and brain atrophy is yet to be established in healthy humans. We combine magnetoencephalo-graphic (MEG) measures of neural processing speed with magnetic resonance imaging (MRI) measures of white and grey matter in a large population-derived cohort to investigate the relationship between age-related structural differences and visual evoked field (VEF) and auditory evoked field (AEF) delay across two different tasks. Here we use a novel technique to show that VEFs exhibit a constant delay, whereas AEFs exhibit delay that accumulates over time. White-matter (WM) microstructure in the optic radiation partially mediates visual delay, suggesting increased transmission time, whereas grey matter (GM) in auditory cortex partially mediates auditory delay, suggesting less efficient local processing. Our results demonstrate that age has dissociable effects on neural processing speed, and that these effects relate to different types of brain atrophy.
  • Kikuchi, David W.; Waldron, Samuel J.; Valkonen, Janne K.; Dobler, Susanne; Mappes, Johanna (2020)
    Mullerian mimicry is a classic example of adaptation, yet Muller's original theory does not account for the diversity often observed in mimicry rings. Here, we aimed to assess how well classical Mullerian mimicry can account for the colour polymorphism found in chemically defended Oreina leaf beetles by using field data and laboratory assays of predator behaviour. We also evaluated the hypothesis that thermoregulation can explain diversity between Oreina mimicry rings. We found that frequencies of each colour morph were positively correlated among species, a critical prediction of Mullerian mimicry. Predators learned to associate colour with chemical defences. Learned avoidance of the green morph of one species protected green morphs of another species. Avoidance of blue morphs was completely generalized to green morphs, but surprisingly, avoidance of green morphs was less generalized to blue morphs. This asymmetrical generalization should favour green morphs: indeed, green morphs persist in blue communities, whereas blue morphs are entirely excluded from green communities. We did not find a correlation between elevation and coloration, rejecting thermoregulation as an explanation for diversity between mimicry rings. Biased predation could explain within-community diversity in warning coloration, providing a solution to a long-standing puzzle. We propose testable hypotheses for why asymmetric generalization occurs, and how predators maintain the predominance of blue morphs in a community, despite asymmetric generalization.
  • Hagens, Eliza R. C.; Henegouwen, Mark I. van Berge; van Sandick, Johanna W.; Cuesta, Miguel A.; van der Peet, Donald L.; Heisterkamp, Joos; Nieuwenhuijzen, Grard A. P.; Rosman, Camiel; Scheepers, Joris J. G.; Sosef, Meindert N.; van Hillegersberg, Richard; Lagarde, Sjoerd M.; Nilsson, Magnus; Räsänen, Jari; Nafteux, Philippe; Pattyn, Piet; Hoelscher, Arnulf H.; Schroeder, Wolfgang; Schneider, Paul M.; Mariette, Christophe; Castoro, Carlo; Bonavina, Luigi; Rosati, Riccardo; de Manzoni, Giovanni; Mattioli, Sandro; Roig Garcia, Josep; Pera, Manuel; Griffin, Michael; Wilkerson, Paul; Chaudry, M. Asif; Sgromo, Bruno; Tucker, Olga; Cheong, Edward; Moorthy, Krishna; Walsh, Thomas N.; Reynolds, John; Tachimori, Yuji; Inoue, Haruhiro; Matsubara, Hisahiro; Kosugi, Shin-ichi; Chen, Haiquan; Law, Simon Y. K.; Pramesh, C. S.; Puntambekar, Shailesh P.; Murthy, Sudish; Linden, Philip; Hofstetter, Wayne L.; Kuppusamy, Madhan K.; Shen, K. Robert; Darling, Gail E.; Sabino, Flavio D.; Grimminger, Peter P.; Meijer, Sybren L.; Bergman, Jacques J. G. H. M.; Hulshof, Maarten C. C. M.; van Laarhoven, Hanneke W. M.; Mearadji, Banafsche; Bennink, Roel J.; Annema, Jouke T.; Dijkgraaf, Marcel G. W.; Gisbertz, Suzanne S. (2019)
    BackgroundAn important parameter for survival in patients with esophageal carcinoma is lymph node status. The distribution of lymph node metastases depends on tumor characteristics such as tumor location, histology, invasion depth, and on neoadjuvant treatment. The exact distribution is unknown. Neoadjuvant treatment and surgical strategy depends on the distribution pattern of nodal metastases but consensus on the extent of lymphadenectomy has not been reached. The aim of this study is to determine the distribution of lymph node metastases in patients with resectable esophageal or gastro-esophageal junction carcinoma in whom a transthoracic esophagectomy with a 2- or 3-field lymphadenectomy is performed. This can be the foundation for a uniform worldwide staging system and establishment of the optimal surgical strategy for esophageal cancer patients.MethodsThe TIGER study is an international observational cohort study with 50 participating centers. Patients with a resectable esophageal or gastro-esophageal junction carcinoma in whom a transthoracic esophagectomy with a 2- or 3-field lymphadenectomy is performed in participating centers will be included. All lymph node stations will be excised and separately individually analyzed by pathological examination. The aim is to include 5000 patients. The primary endpoint is the distribution of lymph node metastases in esophageal and esophago-gastric junction carcinoma specimens following transthoracic esophagectomy with at least 2-field lymphadenectomy in relation to tumor histology, tumor location, invasion depth, number of lymph nodes and lymph node metastases, pre-operative diagnostics, neo-adjuvant therapy and (disease free) survival.DiscussionThe TIGER study will provide a roadmap of the location of lymph node metastases in relation to tumor histology, tumor location, invasion depth, number of lymph nodes and lymph node metastases, pre-operative diagnostics, neo-adjuvant therapy and survival. Patient-tailored treatment can be developed based on these results, such as the optimal radiation field and extent of lymphadenectomy based on the primary tumor characteristics.Trial registrationNCT03222895, date of registration: July 19th, 2017.
  • Sipila, Pyry; Rose, Richard J.; Kaprio, Jaakko (2016)
    AimsTo determine if associations of alcohol consumption with all-cause mortality replicate in discordant monozygotic twin comparisons that control for familial and genetic confounds. DesignA 30-year prospective follow-up. SettingPopulation-based older Finnish twin cohort. ParticipantsSame-sex twins, aged 24-60years at the end of 1981, without overt comorbidities, completed questionnaires in 1975 and 1981 with response rates of 89 and 84%. A total of 15607 twins were available for mortality follow-up from the date of returned 1981 questionnaires to 31December 2011; 14787 twins with complete information were analysed. MeasurementsSelf-reported monthly alcohol consumption, heavy drinking occasions (HDO) and alcohol-induced blackouts. Adjustments for age, gender, marital and smoking status, physical activity, obesity, education and social class. FindingsAmong twins as individuals, high levels of monthly alcohol consumption (259g/month) associated with earlier mortality [hazard ratio (HR)=1.63, 95% confidence interval (CI)=1.47-1.81]. That association was replicated in comparisons of all informatively drinking-discordant twin pairs (HR=1.91, 95% CI=1.49-2.45) and within discordant monozygotic (MZ) twin pairs (HR=2.24, 95% CI=1.31-3.85), with comparable effect size. Smaller samples of MZ twins discordant for HDO and blackouts limited power; a significant association with mortality was found for multiple blackouts (HR=2.82, 95% CI=1.30-6.08), but not for HDO. ConclusionsThe associations of high levels of monthly alcohol consumption and alcohol-induced blackouts with increased all-cause mortality among Finnish twins cannot be explained by familial or genetic confounds; the explanation appears to be causal.
  • Paciaroni, Maurizio; Angelini, Filippo; Agnelli, Giancarlo; Tsivgoulis, Georgios; Furie, Karen L.; Tadi, Prasanna; Becattini, Cecilia; Falocci, Nicola; Zedde, Marialuisa; Abdul-Rahim, Azmil H.; Lees, Kennedy R.; Alberti, Andrea; Venti, Michele; Acciarresi, Monica; Altavilla, Riccardo; D'Amore, Cataldo; Mosconi, Maria G.; Cimini, Ludovica A.; Bovi, Paolo; Carletti, Monica; Rigatelli, Alberto; Cappellari, Manuel; Putaala, Jukka; Tomppo, Liisa; Tatlisumak, Turgut; Bandini, Fabio; Marcheselli, Simona; Pezzini, Alessandro; Poli, Loris; Padovani, Alessandro; Masotti, Luca; Vannucchi, Vieri; Sohn, Sung-Il; Lorenzini, Gianni; Tassi, Rossana; Guideri, Francesca; Acampa, Maurizio; Martini, Giuseppe; Ntaios, George; Karagkiozi, Efstathia; Athanasakis, George; Makaritsis, Kostantinos; Vadikolias, Kostantinos; Liantinioti, Chrysoula; Chondrogianni, Maria; Mumoli, Nicola; Consoli, Domenico; Galati, Franco; Sacco, Simona; Carolei, Antonio; Tiseo, Cindy; Corea, Francesco; Ageno, Walter; Bellesini, Marta; Silvestrelli, Giorgio; Ciccone, Alfonso; Scoditti, Umberto; Denti, Licia; Mancuso, Michelangelo; Maccarrone, Miriam; Orlandi, Giovanni; Giannini, Nicola; Gialdini, Gino; Tassinari, Tiziana; De Lodovici, Maria Luisa; Bono, Giorgio; Rueckert, Christina; Baldi, Antonio; Toni, Danilo; Letteri, Federica; Giuntini, Martina; Lotti, Enrico M.; Flomin, Yuriy; Pieroni, Alessio; Kargiotis, Odysseas; Karapanayiotides, Theodore; Monaco, Serena; Baronello, Mario M.; Csiba, Laszlo; Szabo, Lilla; Chiti, Alberto; Giorli, Elisa; Del Sette, Massimo; Imberti, Davide; Zabzuni, Dorjan; Doronin, Boris; Volodina, Vera; Pd-Mer, Patrik Michel; Vanacker, Peter; Barlinn, Kristian; Pallesen, Lars P.; Kepplinger, Jessica; Deleu, Dirk; Melikyan, Gayane; Ibrahim, Faisal; Akhtar, Naveed; Gourbali, Vanessa; Yaghi, Shadi; Caso, Valeria (2019)
    Background The relationship between different patterns of atrial fibrillation and early recurrence after an acute ischaemic stroke is unclear. Purpose In a prospective cohort study, we evaluated the rates of early ischaemic recurrence after an acute ischaemic stroke in patients with paroxysmal atrial fibrillation or sustained atrial fibrillation which included persistent and permanent atrial fibrillation. Methods In patients with acute ischaemic stroke, atrial fibrillation was categorised as paroxysmal atrial fibrillation or sustained atrial fibrillation. Ischaemic recurrences were the composite of ischaemic stroke, transient ischaemic attack and symptomatic systemic embolism occurring within 90 days from acute index stroke. Results A total of 2150 patients (1155 females, 53.7%) were enrolled: 930 (43.3%) had paroxysmal atrial fibrillation and 1220 (56.7%) sustained atrial fibrillation. During the 90-day follow-up, 111 ischaemic recurrences were observed in 107 patients: 31 in patients with paroxysmal atrial fibrillation (3.3%) and 76 with sustained atrial fibrillation (6.2%) (hazard ratio (HR) 1.86 (95% CI 1.24-2.81)). Patients with sustained atrial fibrillation were on average older, more likely to have diabetes mellitus, hypertension, history of stroke/ transient ischaemic attack, congestive heart failure, atrial enlargement, high baseline NIHSS-score and implanted pacemaker. After adjustment by Cox proportional hazard model, sustained atrial fibrillation was not associated with early ischaemic recurrences (adjusted HR 1.23 (95% CI 0.74-2.04)). Conclusions After acute ischaemic stroke, patients with sustained atrial fibrillation had a higher rate of early ischaemic recurrence than patients with paroxysmal atrial fibrillation. After adjustment for relevant risk factors, sustained atrial fibrillation was not associated with a significantly higher risk of recurrence, thus suggesting that the risk profile associated with atrial fibrillation, rather than its pattern, is determinant for recurrence.
  • Hognert, Helena; Skjeldestad, Finn Egil; Gemzell-Danielsson, Kristina; Heikinheimo, Oskari; Milsom, Ian; Lidegaard, Ojvind; Lindh, Ingela (2018)
    Objectives Compare hormonal contraceptive use, birth and abortion rates among teenagers in the Nordic countries. A secondary aim was to explore plausible explanations for possible differences between countries. Design Ecological study using national registry data concerning births and abortions among all women aged 15-19 years residing in Denmark, Finland, Iceland, Norway and Sweden 2008-2015. Age-specific data on prescriptions for hormonal contraceptives for the period 2008-2015 were obtained from national databases in Denmark, Norway and Sweden. Setting Denmark, Finland, Iceland, Norway and Sweden. Participants Women 15-19 years old in all Nordic countries (749 709) and 13-19 years old in Denmark, Norway and Sweden (815 044). Results Both annual birth rates and abortion rates fell in all the Nordic countries during the study period. The highest user rate of hormonal contraceptives among 15-19-year-olds was observed in Denmark (from 51% to 47%) followed by Sweden (from 39% to 42%) and Norway (from 37% to 41%). Combined oral contraceptives were the most commonly used methods in all countries. The use of long-acting reversible contraceptives (LARC), implants and the levonorgestrel-releasing intrauterine systems, were increasing, especially in Sweden and Norway. In the subgroup of 18-19-year-old teenagers, the user rates of hormonal contraceptives varied between 63% and 61% in Denmark, 56% and 61% in Norway and 54% and 56% in Sweden. In the same subgroup, the steepest increase of LARC was seen, from 2% to 6% in Denmark, 2% to 9% in Norway and 7% to 17% in Sweden. Conclusions Birth and abortion rates continuously declined in the Nordic countries among teenagers. There was a high user rate of hormonal contraceptives, with an increase in the use of LARC especially among the oldest teenagers.
  • Khannoon, Eraqi R.; Ollonen, Joni; Di-Poi, Nicolas (2020)
    Ontogenetic studies are crucial for understanding functional morphology, origin and adaptation of skulls in vertebrates. However, very few studies have so far released complete embryonic series focusing on skull embryonic development in species showing diverse and extreme cranial morphologies such as snakes. The wide distribution and unique reproductive and ecological behaviors of venomous vipers, including the heterogeneity in breeding and egg incubation periods in oviparous species, make this group an excellent new model for studying the diversity of skull developmental processes in snakes. Here we present the first complete description of osteocranium development in a viperine snake, Cerastes cerastes, using detailed analysis of the ossification pattern of individual bones across different embryonic stages based on high-resolution micro-computed tomography data. Particularly, we describe in detail the development of the laterosphenoid from its dorsal and ventral components, dividing the trigeminal foramen into maxillary and mandibular foramina. Furthermore, our data help clarify some controversy concerning the presence and/or origin of structures related to the snake basicranium and braincase roof. For example, our detailed description of supraoccipital development suggests that this bone derived, at least in part, from the tectum posterius, although the involvement of the tectum synoticum cannot be totally excluded. Similarly, the epiotic centers of supraoccipital ossification are confirmed during braincase development, and the ancestral lacrimal bone primordium is observed as a ventral element at the early stages of prefrontal development. Finally, our embryonic C. cerastes data highlight a plausible asymmetry in snake skull development, mostly occurring in the basicranium region, but further investigations of embryonic samples and viper species would be required to confirm such phenomenon.
  • Santos, Susana; Eekhout, Iris; Voerman, Ellis; Gaillard, Romy; Barros, Henrique; Charles, Marie-Aline; Chatzi, Leda; Chevrier, Cecile; Chrousos, George P.; Corpeleijn, Eva; Costet, Nathalie; Crozier, Sarah; Doyon, Myriam; Eggesbo, Merete; Fantini, Maria Pia; Farchi, Sara; Forastiere, Francesco; Gagliardi, Luigi; Georgiu, Vagelis; Godfrey, Keith M.; Gori, Davide; Grote, Veit; Hanke, Wojciech; Hertz-Picciotto, Irva; Heude, Barbara; Hivert, Marie-France; Hryhorczuk, Daniel; Huang, Rae-Chi; Inskip, Hazel; Jusko, Todd A.; Karvonen, Anne M.; Koletzko, Berthold; Kupers, Leanne K.; Lagstrom, Hanna; Lawlor, Debbie A.; Lehmann, Irina; Lopez-Espinosa, Maria-Jose; Magnus, Per; Majewska, Renata; Mäkelä, Johanna; Manios, Yannis; McDonald, Sheila W.; Mommers, Monique; Morgen, Camilla S.; Moschonis, George; Murinova, Lubica; Newnham, John; Nohr, Ellen A.; Andersen, Anne-Marie Nybo; Oken, Emily; Oostvogels, Adriette J. J. M.; Pac, Agnieszka; Papadopoulou, Eleni; Pekkanen, Juha; Pizzi, Costanza; Polanska, Kinga; Porta, Daniela; Richiardi, Lorenzo; Rifas-Shiman, Sheryl L.; Roeleveld, Nel; Santa-Marina, Loreto; Santos, Ana C.; Smit, Henriette A.; Sorensen, Thorkild I. A.; Standl, Marie; Stanislawski, Maggie; Stoltenberg, Camilla; Thiering, Elisabeth; Thijs, Carel; Torrent, Maties; Tough, Suzanne C.; Trnovec, Tomas; van Gelder, Marleen M. H. J.; van Rossem, Lenie; von Berg, Andrea; Vrijheid, Martine; Vrijkotte, Tanja G. M.; Zvinchuk, Oleksandr; van Buuren, Stef; Jaddoe, Vincent W. V. (2018)
    BackgroundGestational weight gain differs according to pre-pregnancy body mass index and is related to the risks of adverse maternal and child health outcomes. Gestational weight gain charts for women in different pre-pregnancy body mass index groups enable identification of women and offspring at risk for adverse health outcomes. We aimed to construct gestational weight gain reference charts for underweight, normal weight, overweight, and grades 1, 2 and 3 obese women and to compare these charts with those obtained in women with uncomplicated term pregnancies.MethodsWe used individual participant data from 218,216 pregnant women participating in 33 cohorts from Europe, North America, and Oceania. Of these women, 9065 (4.2%), 148,697 (68.1%), 42,678 (19.6%), 13,084 (6.0%), 3597 (1.6%), and 1095 (0.5%) were underweight, normal weight, overweight, and grades 1, 2, and 3 obese women, respectively. A total of 138, 517 women from 26 cohorts had pregnancies with no hypertensive or diabetic disorders and with term deliveries of appropriate for gestational age at birth infants. Gestational weight gain charts for underweight, normal weight, overweight, and grade 1, 2, and 3 obese women were derived by the Box-Cox t method using the generalized additive model for location, scale, and shape.ResultsWe observed that gestational weight gain strongly differed per maternal pre-pregnancy body mass index group. The median (interquartile range) gestational weight gain at 40weeks was 14.2kg (11.4-17.4) for underweight women, 14.5kg (11.5-17.7) for normal weight women, 13.9kg (10.1-17.9) for overweight women, and 11.2kg (7.0-15.7), 8.7kg (4.3-13.4) and 6.3kg (1.9-11.1) for grades 1, 2, and 3 obese women, respectively. The rate of weight gain was lower in the first half than in the second half of pregnancy. No differences in the patterns of weight gain were observed between cohorts or countries. Similar weight gain patterns were observed in mothers without pregnancy complications.ConclusionsGestational weight gain patterns are strongly related to pre-pregnancy body mass index. The derived charts can be used to assess gestational weight gain in etiological research and as a monitoring tool for weight gain during pregnancy in clinical practice.
  • Smetana, Ondrej; Mäkilä, Riikka; Lyu, Munan; Amiryousefi, Ali; Rodriguez, Filomeno Sanchez; Wu, Miin-Feng; Sole-Gil, Anna; Gavarron, Marina Leal; Siligato, Riccardo; Miyashima, Shunsuke; Roszak, Pawel; Blomster, Tiina; Reed, Jason W.; Broholm, Suvi; Mähönen, Ari Pekka (2019)
    Wood, a type of xylem tissue, originates from cell proliferation of the vascular cambium. Xylem is produced inside, and phloem outside, of the cambium(1). Morphogenesis in plants is typically coordinated by organizer cells that direct the adjacent stem cells to undergo programmed cell division and differentiation. The location of the vascular cambium stem cells and whether the organizer concept applies to the cambium are currently unknown(2). Here, using lineage-tracing and molecular genetic studies in the roots of Arabidopsis thaliana, we show that cells with a xylem identity direct adjacent vascular cambial cells to divide and function as stem cells. Thus, these xylem-identity cells constitute an organizer. A local maximum of the phytohormone auxin, and consequent expression of CLASS III HOMEODOMAIN-LEUCINE ZIPPER (HD-ZIP III) transcription factors, promotes xylem identity and cellular quiescence of the organizer cells. Additionally, the organizer maintains phloem identity in a non-cell-autonomous fashion. Consistent with this dual function of the organizer cells, xylem and phloem originate from a single, bifacial stem cell in each radial cell file, which confirms the classical theory of a uniseriate vascular cambium(3). Clones that display high levels of ectopically activated auxin signalling differentiate as xylem vessels; these clones induce cell divisions and the expression of cambial and phloem markers in the adjacent cells, which suggests that a local auxin-signalling maximum is sufficient to specify a stem-cell organizer. Although vascular cambium has a unique function among plant meristems, the stem-cell organizer of this tissue shares features with the organizers of root and shoot meristems.
  • Caves, Eleanor M.; Dixit, Tanmay; Colebrook-Robjent, John F. R.; Hamusikili, Lazaro; Stevens, Martin; Thorogood, Rose; Spottiswoode, Claire N. (2021)
    In host-parasite arms races, hosts can evolve signatures of identity to enhance the detection of parasite mimics. In theory, signatures are most effective when within-individual variation is low ('consistency'), and between-individual variation is high ('distinctiveness'). However, empirical support for positive covariation in signature consistency and distinctiveness across species is mixed. Here, we attempt to resolve this puzzle by partitioning distinctiveness according to how it is achieved: (i) greater variation within each trait, contributing to elevated 'absolute distinctiveness' or (ii) combining phenotypic traits in unpredictable combinations ('combinatorial distinctiveness'). We tested how consistency covaries with each type of distinctiveness by measuring variation in egg colour and pattern in two African bird families (Cisticolidae and Ploceidae) that experience mimetic brood parasitism. Contrary to predictions, parasitized species, but not unparasitized species, exhibited a negative relationship between consistency and combinatorial distinctiveness. Moreover, regardless of parasitism status, consistency was negatively correlated with absolute distinctiveness across species. Together, these results suggest that (i) selection from parasites acts on how traits combine rather than absolute variation in traits, (ii) consistency and distinctiveness are alternative rather than complementary elements of signatures and (iii) mechanistic constraints may explain the negative relationship between consistency and absolute distinctiveness across species.
  • Wang, Zhao; Pawar, Prashant Mohan-Anupama; Derba-Maceluch, Marta; Hedenström, Mattias; Chong, Sun-Li; Tenkanen, Maija; Jönsson, Leif J.; Mellerowicz, Ewa (2020)
    Fast-growing broad-leaf tree species can serve as feedstocks for production of bio-based chemicals and fuels through biochemical conversion of wood to monosaccharides. This conversion is hampered by the xylan acetylation pattern. To reduce xylan acetylation in the wood, the Hypocrea jecorina acetyl xylan esterase (HjAXE) from carbohydrate esterase (CE) family 5 was expressed in hybrid aspen under the control of the wood-specific PtGT43B promoter and targeted to the secretory pathway. The enzyme was predicted to deacetylate polymeric xylan in the vicinity of cellulose due to the presence of a cellulose-binding module. Cell-wall-bound protein fractions from developing wood of transgenic plants were capable of releasing acetyl from finely ground wood powder, indicative of active AXE present in cell walls of these plants, whereas no such activity was detected in wild-type plants. The transgenic lines grew in height and diameter as well as wild-type trees, whereas their internodes were slightly shorter, indicating higher leaf production. The average acetyl content in the wood of these lines was reduced by 13%, mainly due to reductions in di-acetylated xylose units, and in C-2 and C-3 mono-acetylated xylose units. Analysis of soluble cell wall polysaccharides revealed a 4% reduction in the fraction of xylose units and an 18% increase in the fraction of glucose units, whereas the contents of cellulose and lignin were not affected. Enzymatic saccharification of wood from transgenic plants resulted in 27% higher glucose yield than for wild-type plants. Brunauer-Emmett-Teller (BET) analysis and Simons' staining pointed toward larger surface area and improved cellulose accessibility for wood from transgenic plants compared to wood from wild-type plants, which could be achieved by HjAXE deacetylating xylan bound to cellulose. The results show that CE5 family can serve as a source of enzymes for in planta reduction of recalcitrance to saccharification.
  • Jalkanen, Joel; Toivonen, Tuuli; Moilanen, Atte (2020)
    Context Spatial conservation prioritization (SCP) has most often been applied to the design of reserve network expansion. In addition to occurrences of species and habitats inside protected area candidate sites, one may also be interested about network-level connectivity considerations. Objectives We applied SCP to the identification of ecological networks to inform the development of a new regional plan for the region of Uusimaa (South-Finland, including the Finnish capital district). Methods Input data were 59 high-quality layers of biotope and species distribution data. We identified ecological networks based on a combination of a Zonation balanced priority ranking map and a weighted range size rarity map, to account for both relative and absolute conservation values in the process. We also identified ecological corridors between protected areas and other ecologically high-priority areas using the corridor retention method of Zonation. Furthermore, we identified candidate sites for habitat restoration. Results We found seven large ecological networks (132-1201 km(2)) which stand out from their surrounding landscape in terms of ecological value and have clear connectivity bottlenecks between them. Highest restoration needs were found between large high-priority sites that are connected via remnant habitat fragments in comparatively highly modified areas. Conclusions Land conversion should be avoided in areas of highest ecological priorities and network-level connectivity. Restoration should be considered for connectivity bottlenecks. Methods described here can be applied in any location where relevant spatial data are available. The present results are actively used by the regional council and municipalities in the region of Uusimaa.
  • Holkeri, Arttu; Eranti, Antti; Haukilahti, M. Anette E.; Kerola, Tuomas; Kenttä, Tuomas V.; Tikkanen, Jani T.; Rissanen, Harri; Heliövaara, Markku; Knekt, Paul; Junttila, M. Juhani; Aro, Aapo L.; Huikuri, Heikki V. (2020)
    BACKGROUND Early repolarization (ER) has been linked to the risk of sudden cardiac death (SCD) in the general population, although controversy remains regarding risks across various subgroups. OBJECTIVE The purpose of this study was to investigate whether age and sex influence the prognostic significance of ER. METHODS We evaluated the 12-lead electrocardiograms of 6631 Finnish general population subjects age >= 30 years (mean age 50.1 +/- 13.9 years; 44.5% men) for the presence of ER (J-point elevation >= 0.1 mV in >= 2 inferior/lateral leads) and followed them for 24.4 +/- 10.3 years. We analyzed the association between ER and the risk of SCD, cardiac death, and ad-cause mortality in subgroups according to age (= 50 years) and sex. RESULTS ER was present in 367 of the 3305 subjects age = 50 years. ER was not associated with any of the endpoints in the entire study population. After adjusting for clinical factors, ER was associated with SCD (hazard ratio [HR] 1.88; 95% confidence interval [CI] 1.16-3.07) in subjects CONCLUSION ER is associated with SCD in subjects younger than 50 years, particularly in women, but not in subjects 50 years and older.
  • Marchaudon, A.; Blelly, P. -L.; Grandin, M.; Aikio, A.; Kozlovsky, A.; Virtanen, I. (2018)
    Our aim is to understand the effect of high-speed stream events on the high-latitude ionosphere and more specifically the decrease of the f(o)F(2) frequency during the entire day following the impact. First, we have selected one summertime event, for which a large data set was available: Super Dual Auroral Radar Network (SuperDARN) and European Incoherent SCATter (EISCAT) radars, Tromso and Sodankyla ionosondes, and the CHAllenging Minisatellite Payload (CHAMP) satellite. We modeled with the IPIM model (IRAP Plasmasphere Ionosphere Model) the dynamics of the ionosphere at Tromso and Sodankyla using inputs derived from the data. The simulations nicely match the measurements made by the EISCAT radar and the ionosondes, and we showed that the decrease of f(o)F(2) is associated with a transition from F-2 to F-1 layer resulting from a decrease of neutral atomic oxygen concentration. Modeling showed that electrodynamics can explain short-term behavior on the scale of a few hours, but long-term behavior on the scale of a few days results from the perturbation induced in the atmosphere. Enhancement of convection is responsible for a sharp increase of the ion temperature by Joule heating, leading through chemistry to an immediate reduction of the F-2 layer. Then, ion drag on neutrals is responsible for a rapid heating and expansion of the thermosphere. This expansion affects atomic oxygen through nonthermal upward flow, which results in a decrease of its concentration and amplifies the decrease of [O]/[N-2] ratio. This thermospheric change explains long-term extinction of the F-2 layer.
  • Björklund, Heidi; Parkkinen, Anssi; Hakkari, Tomi; Heikkinen, Risto K; Virkkala, Raimo; Lensu, Anssi (2020)
    Intensive management of boreal forests impairs forest biodiversity and species of old-growth forest. Effective measures to support biodiversity require detection of locations valuable for conservation. We applied species distribution models (SDMs) to a species of mature forest, the northern goshawk (Accipiter gentilis, goshawk), that is often associated with hotspots of forest biodiversity. We located optimal sites for the goshawk on a landscape scale, assessed their state under intensified logging operations and identified characteristics of goshawks' nesting sites in boreal forests. Optimal sites for the goshawk covered only 3.4% of the boreal landscape and were mostly located outside protected areas, which highlights the importance of conservation actions in privately-owned forests. Furthermore, optimal sites for the goshawk and associated biodiversity were under threat. Half of them were logged to some extent and 10% were already lost or notably deteriorated due to logging shortly after 2015 for which our models were calibrated. Habitat suitability for the goshawk increased with increasing volume of Norway spruce (Picea abies) peaking at 220 m(3) ha(-1), and with small quantities of birches (Betula spp.) and other broad-leaved trees. Threats to biodiversity of mature spruce forests are likely to accelerate in the future with increasing logging pressures and shorter rotation periods. Logging should be directed less to forests with high biodiversity. Continuous supply of mature spruce forests in the landscape should be secured with a denser network of protected areas and measures that aid in sparing large entities of mature forest on privately-owned land.
  • Lehtinen, Laura; Vesterkvist, Pia; Roering, Pia; Korpela, Taina; Hattara, Liisa; Kaipio, Katja; Mpindi, John-Patrick; Hynninen, Johanna; Auranen, Annika; Davidson, Ben; Haglund, Caj; Iljin, Kristiina; Grenman, Seija; Siitari, Harri; Carpen, Olli (2016)
    Preoperative diagnostics of ovarian neoplasms rely on ultrasound imaging and the serum biomarkers CA125 and HE4. However, these markers may be elevated in non-neoplastic conditions and may fail to identify most non-serous epithelial cancer subtypes. The objective of this study was to identify histotype-specific serum biomarkers for mucinous ovarian cancer. The candidate genes with mucinous histotype specific expression profile were identified from publicly available gene-expression databases and further in silico data mining was performed utilizing the MediSapiens database. Candidate biomarker validation was done using qRT-PCR, western blotting and immunohistochemical staining of tumor tissue microarrays. The expression level of the candidate gene in serum was compared to the serum CA125 and HE4 levels in a patient cohort of prospectively collected advanced ovarian cancer. Database searches identified REG4 as a potential biomarker with specificity for the mucinous ovarian cancer subtype. The specific expression within epithelial ovarian tumors was further confirmed by mRNA analysis. Immunohistochemical staining of ovarian tumor tissue arrays showed distinctive cytoplasmic expression pattern only in mucinous carcinomas and suggested differential expression between benign and malignant mucinous neoplasms. Finally, an ELISA based serum biomarker assay demonstrated increased expression only in patients with mucinous ovarian cancer. This study identifies REG4 as a potential serum biomarker for histotype-specific detection of mucinous ovarian cancer and suggests serum REG4 measurement as a non-invasive diagnostic tool for postoperative follow-up of patients with mucinous ovarian cancer.
  • RAXO Study Grp; Osterlund, Pia; Salminen, Tapio; Soveri, Leena-Maija; Kallio, Raija; Kellokumpu, Ilmo; Lamminmäki, Annamarja; Halonen, Päivi; Ristamäki, Raija; Lantto, Eila; Uutela, Aki; Osterlund, Emerik; Ovissi, Ali; Nordin, Arno; Heervä, Eetu; Lehtomäki, Kaisa; Räsänen, Jari; Murashev, Maija; Aroviita, Laura; Jekunen, Antti; Lindvall-Andersson, Renee; Nyandoto, Paul; Kononen, Juha; Lepistö, Anna; Poussa, Tuija; Muhonen, Timo; Algars, Annika; Isoniemi, Helena (2021)
    Background: Resection of colorectal cancer (CRC) metastases provides good survival but is probably underused in real-world practice. Methods: A prospective Finnish nationwide study enrolled treatable metastatic CRC patients. The intervention was the assessment of resectability upfront and twice during first-line therapy by the multidisciplinary team (MDT) at Helsinki tertiary referral centre. The primary outcome was resection rates and survival. Findings: In 2012-2018, 1086 patients were included. Median follow-up was 58 months. Multiple metastatic sites were present in 500 (46%) patients at baseline and in 820 (76%) during disease trajectory. In MDT assessments, 447 (41%) were classified as resectable, 310 (29%) upfront and 137 (18%) after conversion therapy. Sixhundred and ninety curative intent resections or local ablative therapies (LAT) were performed in 399 patients (89% of 447 resectable). Multiple metastasectomies for multisite or later developing metastases were performed in 148 (37%) patients. Overall, 414 liver, 112 lung, 57 peritoneal, and 107 other metastasectomies were performed. Median OS was 80.4 months in R0/1-resected (HR 0.15; CI95% 0.12-0.19), 39.1 months in R2-resected/LAT (0.39; 0.29-0.53) patients, and 20.8 months in patients treated with "systemic therapy alone" (reference), with 5-year OS rates of 66%, 40%, and 6%, respectively. Interpretation: Repeated centralized MDT assessment in real-world metastatic CRC patients generates high resectability (41%) and resection rates (37%) with impressive survival, even when multisite metastases are present or develop later. (C) 2021 The Author(s). Published by Elsevier Ltd.