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The evaluation of diagnostic systems is pivotal for ensuring the deployment of high-quality solutions, especially given the pronounced context-sensitivity of certain systems, particularly in fields such as biomedicine. Of notable importance are predictive models where the target variable can encompass multiple values (multiclass), especially when these classes exhibit substantial frequency disparities (imbalance). In this study, we introduce the Imbalanced Multiclass Classification Performance (IMCP) curve, specifically designed for multiclass datasets (unlike the ROC curve), and characterized by its resilience to class distribution variations (in contrast to accuracy or F β -score). Moreover, the IMCP curve facilitates individual performance assessment for each class within the diagnostic system, shedding light on the confidence associated with each prediction—an aspect of particular significance in medical diagnosis. Empirical experiments conducted with real-world data in a multiclass context (involving 35 types of tumors) featuring a high level of imbalance demonstrate that both the IMCP curve and the area under the IMCP curve serve as excellent indicators of classification quality. [ABSTRACT FROM AUTHOR]

Biclustering is a two-dimensional data analysis technique that, applied to a matrix, searches for a subset of rows and columns that intersect to produce a submatrix with given, expected features. Such an approach requires different methods to those of typical classification or regression tasks. In recent years it has become possible to express biclustering goals in the form of Boolean reasoning. This paper presents a new, heuristic approach to bicluster induction in binary data. [ABSTRACT FROM AUTHOR]

Biclustering is a two-dimensional data analysis technique, where submatrices of a given data matrix are looked for. Its extension into three-dimensional data is called triclustering. In the paper, a new generalized look into n-dimensional binary data n-clustering is presented. The searching is performed in terms of the Boolean reasoning paradigm, where the original case (the data) is coded into the Boolean formula and its prime implicants are equivalent to the solutions of the original issue. The correctness (finding n-clusters containing only 0s or 1s) and maximality (the n-cluster cannot be expanded in any dimension without the correctness requirement violation) of such an approach have strong mathematical foundations. The paper also shows the application of Boolean reasoning-based n-clustering for small three- and four-dimensional artificial data as well as for some biomedical ones. [ABSTRACT FROM AUTHOR]

Key message: Embryonic axes of acorns have greater variability of mass than cotyledons or pericarp. Above/below ground seedling mass depends on oak species. Species of the genus oak are of great importance for forest ecosystems in almost all of the Holarctic. Knowledge of the diversity of the size of acorns and their parts would allow better use of the opportunity of genetic resources storage, both for the protection of endangered oak species and for forestry practices. The initial development of seedlings in reference to the size of the acorn, its parts and acorn maturation time was also investigated. The fresh and dry mass of individual acorns, embryonic axes and cotyledons of 15 species (Quercus agrifolia, Q. gambelli, Q. kelloggii, Q. alba, Q. bicolor, Q. coccinea, Q. falcata, Q. lyrata, Q. nigra, Q. prinus, Q. rubra, Q. cerris, Q. ilex, Q. petraea, and Q. robur) were determined. In the second part of the study, the mass of the ca. 3-month-old seedlings that had completed the first stage of growth, with a division on the leaves, the shoot and the root, was measured. The greatest variation in mass both between and within the species was demonstrated for the embryonic axis. The mass of seedlings depends on the size of the acorn and the cotyledons contained therein; whereas, the mass of the embryonic axis has no significant influence on the mass of seedlings. [ABSTRACT FROM AUTHOR]

Black poplar ( Populus nigra L.) is a widely distributed species that plays a crucial role in riparian forest ecosystems. Due to a reduction in its natural habitats and hybridization with introduced poplar species clones, its genetic pool is decreasing and efforts are required to preserve this species. Seeds of black poplar are short-lived and quickly lose viability during conventional storage in gene banks. Therefore, in order to preserve ex situ the genetic diversity of this species, the feasibility of seed cryopreservation in liquid nitrogen (at −196 °C, LN) for periods of 24 h and 2 years was investigated. Seeds were harvested from three individual trees (two provenances) and desiccated to different levels of water content (WC) in the range of 0.02-0.35 g g (g HO/g dry mass, g g) prior to immersion in LN. Seed germination was assessed after each treatment. P. nigra seeds tolerated desiccation to WC 0.07 g g but after severe desiccation to WC <0.05 g g exhibited a significant reduction in germination. Results indicated that all black poplar seeds, regardless of origin, year of harvesting and seed quality, could be cryopreserved for 24 h when their WC was in the range of 0.11-0.17 g g. Physiology of P. nigra seeds showed in this paper is consistent with attributes of intermediate seed storage behavior. This study provides a foundation for using cryopreservation for the ex situ conservation of P. nigra seeds. [ABSTRACT FROM AUTHOR]

Pedunculate oak ( Quercus robur) is an ecologically and economically important forest tree species which produces seeds that are classified as recalcitrant. Thus, cryopreservation of seed meristems is a method for long-term preservation of this germplasm in gene banks. During cryopreservation, many factors, such as desiccation, cryoprotection and cooling/rewarming, can induce stress in the frozen meristems. In this study, in vitro survival and the global DNA methylation level of plumules after cryoprotection, desiccation and cryostorage was evaluated. Results indicated that both desiccation and storage in liquid nitrogen have negligible influence on DNA methylation status of Q. robur plumules. These findings support the cryopreservation of plumules as an appropriate method for conservation of Q. robur germplasm. [ABSTRACT FROM AUTHOR]

Bleeding negatively affects prognosis and adherence to antiplatelet therapy after acute coronary syndromes (ACSs). The potential association of on-aspirin platelet reactivity and bleeding is not established. We sought to determine whether low on-aspirin platelet reactivity (LAPR) is associated with bleeding events and antiplatelet therapy compliance in patients with ACSs receiving coronary stenting. On-aspirin platelet reactivity was measured by the VerifyNow™ Aspirin assay (Accumetrics Inc., San Diego, CA, USA) in 531 patients with ACS. Cut-offs for LAPR were calculated by receiver-operating characteristic curve (ROC) analysis. Bleeding was reported according to Bleeding Academic Research Consortium (BARC) definition. The endpoints were minor bleeding (BARC types 1 or 2), major bleeding (BARC types 3 or 5) and antiplatelet therapy cessation during 6-months follow-up. By ROC analysis the VerifyNow™ Aspirin assay was able to distinguish between patients with and without minor bleeding (area under the curve [AUC] 0.66, 95 % confidence interval [CI] 0.62-0.70, P < 0.0001) whereas major bleeding could not be predicted by the assay (AUC 0.54, 95 % CI 0.49-0.58, P = 0.473). By logistic regression, LAPR was associated with increased risk of minor bleeding (odds ratio [OR] 4.32, 95 % CI 2.78-6.71, P < 0.0001) but not major bleeding (OR 2.05, 95 % CI 0.83-5.06, P = 0.117). Antiplatelet therapy discontinuation was more frequent in patients with LAPR as compared to those with no LAPR (21.6 vs. 9.1 %, P = 0.0008). In conclusion, early point-of-care on-aspirin platelet reactivity testing in ACS may identify patients with increased risk of minor bleeding events and subsequent discontinuation of antiplatelet therapy. The possible impact of LAPR on major bleeding needs to be determined in larger trials. [ABSTRACT FROM AUTHOR]

A vitrification method enabled efficient cryopreservation of embryogenic tissue (ETs) of Norway spruce ( Picea abies L.) at −196 °C in liquid nitrogen (LN). Correctly formed, normal somatic embryos were generated from ETs that had been thawed after removal from LN. The pregrowth-dehydration method involved preculture of ETs with sucrose (0.25-1.00 M) in the presence or absence of 10 μM abscisic acid (ABA), followed by air-drying for 2 h and rapid freezing in LN. Pretreatment of ETs with both sucrose and ABA promoted ET growth after preculture and thawing more effectively than treatment with sucrose alone. Survival of ETs after thawing from LN using both sucrose and ABA was 54.4 % compared to pretreatment with sucrose alone which was 20 %. Addition of ABA in the preculture medium also improved the ability of ETs to form cotyledonary stage somatic embryos. The somatic embryos, which had normal shoot and root apices and the correct number of cotyledons, were indistinguishable from regenerants obtained from control cultures. Genetic analysis of control and cryopreserved ETs, as well as somatic embryos derived from cryopreserved ETs, indicated that the cryopreservation method had no effect on any of the five microsatellite loci (SpAGC1, SpAGC2, SpAGG3, SpAC1H8, and SpAC1F7) tested. The cryopreservation protocol outlined should enable the long-term storage of valuable clones of Norway spruce in LN, potentially for hundreds of years. [ABSTRACT FROM AUTHOR]

Successful cryopreservation of Q. robur germplasm as plumules (i.e. shoot apical meristems of embryos) is described in this paper. After excision from the recalcitrant seeds and preliminary storage in 0.5 M sucrose solution (18 h), the plumules were subjected to cryoprotection (in 0.75 M sucrose, followed by 1.0 M sucrose and 1.5 M glycerol solutions), and next to desiccation (over silica gel or in nitrogen gas) and cooling (in slush at -210°C or in vials filled with liquid nitrogen, LN, −196°C), and were then cryostored for 24 h. High percentage of survival was obtained after cryostorage (21-67%, depending on pretreatment, assessed in vitro by greening plumules that increased in size). Desiccation of plumules over silica gel resulted in significantly higher survival after cryopreservation (58%) in comparison with desiccation in nitrogen gas (29%), with regrowth (shoots with leaves) 5-18%. The extent of plumule desiccation was comparable in both methods, in which drying of plumules for 20 min decreased the water content to 0.5-0.6 g HO g dry weight before LN exposure. The type of LN exposure did not significantly influence plumule survival and regrowth after cryostorage. Plumules isolated from acorns of four provenances survived cryostorage after cryoprotection followed by desiccation over silica gel and direct cooling in vials with LN (survival 51-76%, regrowth 8-20%). Normal plants developed from the recovered shoots after rooting. The presented protocol for Q. robur plumule cryopreservation may offer a potential approach for establishing germplasm conservation in gene banks for Quercus species. [ABSTRACT FROM AUTHOR]

This short article describes two kernel algorithms of the regression function estimation. One of them is called HASKE and has its own heuristic of the h parameter evaluation. The second is a hybrid algorithm that connects the SVM and HASKE in such a way that the definition of the local neighborhood is based on the definition of the h-neighborhood from HASKE. Both of them are used as predictors for time series. [ABSTRACT FROM AUTHOR]

Two-year-old embryogenic tissues (ET) of Picea omorika (Pančić) Purk. were successfully cryopreserved after preculture with sucrose, air-drying for 2 h, and freezing in liquid nitrogen (LN). The preculture protocol consisted of passaging the ET onto standard Litvay medium containing increasing concentrations of sucrose (0.25 M sucrose for 24 h, 0.5 M for 24 h, 0.75 M for 2 days, and 1.0 M for 3 days) for 7 days, at 25°C, and in the dark. The clumps were subsequently air-dried over silica gel, down to a 20% water content (based on fresh weight), placed in cryovials, and immersed in liquid nitrogen (LN) for 24 h. These were thawed at 42°C and progressively rehydrated in phytagel-solidified LM media containing decreasing concentrations of sucrose. After 3 weeks of in vitro culture, surviving clumps were friable and white in color, similar to their morphology prior to cryostorage. The frequency of bacterial and fungal contamination was higher if ET was frozen in LN-containing vials than in LN-free vials. This efficient cryopreservation protocol would be useful for the ex-situ conservation of P. omorika germplasm in gene banks at very low temperatures. [ABSTRACT FROM AUTHOR]

People whom the editor would like to thank for their contribution to review manuscripts for the periodical are listed which includes Ahmad Omar; Christian Schopke and Elena Popova.