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The efficient planning and control of timber harvesting operations is crucial to growth productivity and reducing costs, and different systems or methods are applied to obtain elevated performance. In particular, cable yarding is a highly appreciated and very efficient wood extraction method in areas that are difficult to access with ground-based extraction machines. Combined logging systems are not diffuse and not often implemented. For this reason, the use and the application of innovative methods are limited. However, some combinations have recently been observed in forest operations. This study, conducted in a deciduous stand in Bulgaria, paid attention to the combination of a tractor-mounted tower yarder (Valentini V400) with a clambunk skidder (Timberjack 1010D), aiming to examine the viability and develop the operational efficiency of the two-stage extraction system and to define the time, log volume extracted per unit by the yarder and the clambunk, and the yarding and skidding costs. The researchers carried out a time-motion study and performed a regression analysis to identify those variables that are most likely to affect the duration of work elements and productivity. For cost analysis, the COST model was used. The mean productivity of the tower yarder was 10.34 m3/PMH and 8.11 m3/SMH, while for the clambunk skidder, the productivity was 6.23 m3/PMH and 4.93 m3/SMH. The net costs for the combined logging system were calculated as 120.87 €/PMH and 14.93 €/m3. This study adds new data about the correct use of both machines, supporting their application in beech forests. [ABSTRACT FROM AUTHOR]

The present study is oriented towards Leader approach and its contribution to the sustainable development of rural territories in Bulgaria. The upgraded model for decentralized and integrated development of rural regions has been implemented in Bulgaria since 2014. The goal of the study is to trace and analyze the actual contribution and the effect from the work of the local initiative groups and the implementation of the approach on a local and national level, and identify the problems and derive the solutions for optimization of the processes, aiming at achieving greater sustainability in the territorial development of rural regions. The main hypothesis is that the approach is universal and sustainable instrument for development of rural regions, but its full potential has not been completely deployed under the conditions in Bulgaria, yet. To this end, the implementation of the strategies for development of pre-selected local action groups is analysed, depending on certain criteria. Empirical data have been summarized and the opportunities for increase of the efficiency of the acquired European funds on territorial scale have been substantiated. [ABSTRACT FROM AUTHOR]

The primary trends defining the paths toward sustainable development in rural areas of Bulgaria underscore the significant influence of human resources., and the priorities are oriented towards stimulation of the vocational training and science based skills, obtained through appropriate education and specialized training, and leading to success in the development and management of the local economy. The tendency, related to the problem is highlighted as the shortage of adequately educated and skilled entrepreneurs capable of harnessing technological advantages in agricultural production and implementing innovative technologies. The goal of our study is related to investigation and summarization of basic tendencies in this aspect, within Bulgarian agricultural enterprises, the emphasis lies on the crucial connection between theoretical knowledge and hands-on experience, particularly highlighting the importance of educating and training agricultural producers. The education and practical application of scientific knowledge by those engaged in agriculture are vital components for achieving success and ensuring the sustainability of economic endeavours at the local level. By promoting education and training for individuals involved in agricultural activities in the agrarian sector, the agriculture guarantees its sustainable and efficient development, which without doubt reflects on the increase of the sustainability of the rural territories, as a whole. The results of the study formulate guidelines, conclusions and recommendations related to recognition of the need of ensuring the proper education and training of agricultural producers, especially in the realm of environmentally friendly practices and innovative technologies. In conclusion, the synthesized research findings provide insight into the tendencies in basic strategic documents supporting knowledge, as well as data for the educational status in the Bulgarian agrarian sector regarding the potential and significance of the human factor. Future guidelines for the study in the sphere of human resources are outlined in the modern agriculture and the Bulgarian rural territories. [ABSTRACT FROM AUTHOR]

The article explores the transformative effect of the digital innovations in the agrarian sector (in particular ruminant breeding) by tracking both the opportunities, and the challenges, which they represent for the sustainable development of the modern agriculture. Integration of digital technologies in cattle-breeding becomes more and more common, offering potential solutions for increasing of the efficiency, productivity and ecological sustainability. The change towards digitalization brings different challenges, varying from problems related to accessibility to concerns, related to data security and ethical consequences. Based on the existing literature and empirical evidence, this research provides complete analysis of the current conjuncture of the digital innovations in livestock industry, assesses the potential benefits from them and explores the barriers preventing their broad acceptance. The conclusions contribute to nuanced understanding of the role, which the digital technologies play in shaping the future of the sustainable agriculture and the rural areas in Bulgaria. The implemented retrospective analysis shows that the problematic agricultural holdings can be encompassed by digitalization only if serious financial investments are made. [ABSTRACT FROM AUTHOR]

Modern agriculture poses new challenges related to the increase of the need of sustainable development of the agrarian sector, and rural territories, respectively. The use of large amounts of chemical preparations in agriculture inevitably hides a number of possibilities for dangers, both for all mankind and for the natural environment. The main goal of this article is to analyze and evaluate the current state of use of pesticides and fertilizers in Bulgaria, as part of the agro-ecological indicators affecting the climate and natural ecosystems. As a result from the research carried out we found that the levels of pesticide use in Bulgaria are below the average, but the last years are marked by a tendency for gradual increase of the areas of the used quantities of nitrogen fertilizers, manure and organic fertilizer, and a deficit in the Phosphorous balance in soil was noted. We need lowering of the degree of ecological risks related to use of pesticides and fertilizers in Bulgaria. This way the results will be multiplied for achieving higher level of economic, social and ecological sustainability in the development of individual rural territories. [ABSTRACT FROM AUTHOR]

Examination of the technical and economic dimensions of skidding operations is imperative for sustainable forest management, offering invaluable insights crucial for the formulation of sustainable forestry strategies. In many countries, the shift from modified agricultural machinery to purpose-built forest machinery has become apparent in forest operations. However, this transition often accompanies a reduction in logging crew size, raising new questions about productivity, costs, and ergonomics of the introduced harvesting systems. This study investigates two skidding systems utilizing the cable-grapple skidder Welte 115/5L, differing in work team size: one with one skidder operator and two chainsaw operators (WT3) and the other with one skidder operator and one chainsaw operator (WT2). Conducted in natural European beech forests in southern Bulgaria, the research focused on the group shelterwood system within the Natura 2000 network. Both WT3 and WT2 exhibited net skidding productivity of 9.96 m3 PMH−1 over a mean skidding distance of 300 m and a mean winching distance of 20 m, outperforming conventional systems in the area. Despite this, there were notable differences in gross skidding productivity (8.64 m3 SMH−1 for WT3 vs. 7.30 m3 SMH−1 for WT2), affecting skidding cost (EUR 5.41 m−3 for WT3 vs. EUR 6.62 m−3 for WT2) and unit production cost (EUR 9.33 m−3 vs. EUR 11.53 m−3). This study highlights that the cable-grapple skidder can be effectively employed by smaller teams, providing higher productivity, lower unit cost, and increased flexibility during piling, primarily due to the presence of the knuckle-boom loader. While WT2 experienced more delays and production pressure, the findings suggest that WT3 represents a balanced option for small logging crews, ensuring sustainable forest operations in the face of workforce challenges. [ABSTRACT FROM AUTHOR]

Cable-based yarding technology has had a long tradition on steep slopes in Europe, and the new implementation of yarding functions in recent decades favored operational efficiency and lower extraction costs. The main goal of this study was to evaluate the performance of the Syncrofalke 3t truck-mounted Processor Tower Yarder (PTY) on steep terrain, in coniferous forests managed with the shelterwood system. In particular, the aim was to determine PTY productivity and costs, with attention to parameters that could increase PTY effectiveness. The study was carried out in the Sredna Gora Mountains, Central Bulgaria, in pure Scots pine stand, with trees of average DBH = 34 cm and height = 22 m. The study was carried out in six corridors with 120 work cycles of tree extraction up the hill, 28° (53%). The mean productivity of PTY was 15.20 m3 per productive machine hour (PMH) and 12.29 m3 per scheduled machine hour (SMH) and was mainly influenced by the productivity of the yarder unit. Under the given conditions, the performance of PTY significantly increased if more than one tree (at least two trees) were attached and extracted per yarder cycle, since the productivity of the processor was approximately twice that of the yarder. The gross costs of the studied PTY were calculated at 297.48 EUR PMH−1 and 16.17 EUR m−3. The variable costs (75%) predominate in the net costs distribution, followed by the fixed costs (15%) and the labor costs (10%). The time, productivity and cost results obtained showed the high efficiency and level of integration of PTY operations in order to achieve economic efficiency of logging in montane pine forest managed in a shelterwood system. [ABSTRACT FROM AUTHOR]

This article focuses on the dynamics of slope processes and the characteristics of their deposits in the Viskyar Mountain, SW Bulgaria. For the purpose of the study, 4 key sites with а different lithology, exposition, slope and altitude were observed. The results are gathered from 2-months period of monitoring. [ABSTRACT FROM AUTHOR]

The paper investigates the accuracy of the model predictive control (MPC) method for finding on-line approximate optimal feedback control for Bolza-type problems on a fixed finite horizon. The predictions for the dynamics, the state measurements, and the solution of the auxiliary open-loop control problems that appear at every step of the MPC method may be inaccurate. The main result provides an error estimate of the MPC-generated solution compared with the optimal open-loop solution of the "ideal" problem, where all predictions and measurements are exact. The technique of proving the estimate involves an extension of the notion of strong metric subregularity of set-valued maps and utilization of a specific new metric in the control space, which makes the proof nonstandard. The result is specialized for two problem classes: coercive problems and affine problems. [ABSTRACT FROM AUTHOR]

The aim of this experimental work was to investigate the dependence of the flux of UF10-PAN membrane with 10 kDa molecular weight cut-off on the working pressure of 0.2 MPa, 0.3 MPa, 0.4 MPa and 0.5 MPa at feed flow rates of 190, 260 and 330 dm3.h-1 at different volume reduction ratios (VRR = 2 and VRR = 4) during ultrafiltration of goat's milk. The data showed that an increase in the working pressure from 0.2 MPa to 0.5 MPa increases the flux of the used membrane at all feed flow rates and volume reduction ratios investigated. The highest values of the flux were obtained at a pressure of 0.5 MPa, at a feed flow rate of 330 dm3.h-1 and VRR = 2, and the lowest - at a pressure of 0.2 MPa, at a feed flow rate of 190 dm3.h-1 and VRR = 4. Single-factor regression models were obtained for the flux of the membrane studied depending on the working pressure at all feed flow rates and volume reduction ratios investigated. [ABSTRACT FROM AUTHOR]

The species Festuca valesiaca, F. rupicola, F. galiciensis, F. macutrensis (F. valesiaca agg.), and F. pallens (F. glauca agg.) were analyzed by polyacrylamide gel electrophoresis (PAGE), in order to evaluate their systematic relationships. Affinities among them were assessed by coefficient of divergence D. Averaged for four enzyme markers, the mean values of coefficient D for comparison of F. pallens with the species of F. valesiaca group were the highest (0.34–0.45) and indicated the remote position of the former species within the studied group. Mean values of D for comparison within F. valesiaca agg. were lower and suggested close mutual affinities. The results are generally in concordance with the recent systematics of the narrow-leaved fescues, on the basis of morphological and anatomical features. [ABSTRACT FROM AUTHOR]

Thin-layer chromatography (TLC) was employed to analyze the phenolic compounds' patterns of six Ukrainian taxa of the Festuca valesiaca group in an attempt to reveal the systematic relationships among them. The results showed that the species F. pseudodalmatica was among the most distantly positioned taxa within the studied species. The species F. valesiaca, F. rupicola, F. arietina, F. macutrensis, and F. galiciensis demonstrated higher mutual affinities. Generally, all studied species form a closely related group as judged by their phenolic compounds' composition. [ABSTRACT FROM AUTHOR]

Polyacrylamide gel electrophoresis (PAGE) was used to study the isoenzyme composition of five taxa of genus Festuca in an attempt to reveal their genetic and systematic relationships. The species F. valesiaca, F. rupicola, F. galiciensis, and F. macutrensis were closely related but different entities within genus Festuca. The species F. pallens occupied a more remote position in regard to species belonging to F. valesiaca agg. Thus, the division of thin-leaved fescues into aggregates based on taxonomy (morphology and anatomy) was supported by an independent biosystematic approach relying on molecular markers. Thus, the results generally support the recent systematic and taxonomic treatment of narrow-leaved fescues. [ABSTRACT FROM AUTHOR]

This article presents the FPGA vision and robotic system on Altera's De2 board. The object detection algorithm implemented in FPGA was based on feature detection and image filtering. A software-based algorithm was independently developed and examined in MATLAB to evaluate its performance and verify its effectiveness. Furthermore, to detect the identities of the objects in the current frame beginning from the identities of the objects in the previous frame, a graph matching algorithm is performed. The experimental data are processed with recurrent Kalman filter. Difficult to obtain reliably eliminate global movement as error correlation is present in the image frame and the inadequacy of the subject and the background helps to produce errors. Although the system can be furthered improved to obtain better results, overall the project was a success as it enabled any inputted face to be accurately detected and tracked. [ABSTRACT FROM AUTHOR]

Polyacrylamide gel electrophoresis (PAGE) was employed to analyze seed protein composition in natural populations of eight Ukrainian taxa of the genus Festuca in an attempt to reveal systematic relationships among them. The results of the study have shown that the species F. polesica is the most distantly positioned taxon within the studied group of genus Festuca. The species F. pallens, F. psammophila and F. ovina are well defined entities, with specific patterns of their seed proteins. These taxa are differentiated from each other and clearly distinct from the taxa of F. valesiaca group. The species of F. valesiaca agg., namely, F. rupicola, F. arietina, F. macutrensis, and F. galiciensis are closely related taxa demonstrating a high level of similarity, as judged by their seed proteins. Other biochemical markers are needed to clarify the systematic relationships among the species of F. valesiaca agg. [ABSTRACT FROM AUTHOR]

Polyacrylamide gel electrophoresis (PAGE) was employed to examine the variation of six isoenzymes, in an attempt to clarify the systematic relationships among Melica transsilvanica, M. ciliata, M. nutans, and M. uniflora. Their affinities were assessed by calculating the coefficient of divergence D. Averaged over the six surveyed enzymes, the mean values of coefficient D demonstrated that the species M. uniflora was equidistantly and far positioned from the species pairs M. ciliata (D = 0.56) and M. transsilvanica (D = 0.57), while the last two species were much close to each other (D = 0.33), as compared to M. uniflora. On the other hand, due to the number of species-specific isoforms, the species M. transsilvanica seems to be a different genetic entity, as compared to M. ciliata. It was concluded that M. transilvanica and M. ciliata were closely related but genetically different entities within genus Melica. These two species were almost equidistantly and far positioned from both M. uniflora and M. nutans. Results of the present study are in concordance with the main morphological features of the examined taxa of genus Melica. [ABSTRACT FROM AUTHOR]

Polyacrylamide gel electrophoresis (PAGE) was employed to examine the variation of ten isoenzyme markers in an attempt to assess the systematic and genetic relationships between Elymus repens, E. hispidus and their hybrid E. ×mucronatus. It was found that the hybrid shared most isoenzyme profiles and isoforms of its parents and high genetic affinity among the studied taxa was revealed. The isoenzyme structure of the hybrid resembled rather the structure of E. repens. Two alternative interpretations of systematic and genetic relationships among the hybrid E. ×mucronatus and its parents are discussed. [ABSTRACT FROM AUTHOR]

Liquidity is of great significance for the stability of credit institutions and the banking system as a whole. In normal circumstances, the capital adequacy of banks is determined as a key factor for stability. But, during economic crisis, the susceptibility of credit institutions to a shortage of available cash resources in order to cover depositors' withdrawals is intensified. This directs our attention toward effective liquidity management. Financial cataclysms on a global scale caused by the crisis in the USA during 2007, and the speedy "infection" of the economies of the developed countries showed that gaps in the management of financial institutions can lead to considerable losses on a world-wide scale. The aim of this study is to assess the liquidity situation of the Bulgarian banking system based on generally accessible (public) information by applying ratio analysis tools. Through the use of key indicators of liquidity assessment, the trends in its development for 2007-2013 are presented. A general assessment of the liquidity situation for banks in Bulgaria is outlined. [ABSTRACT FROM AUTHOR]

Although NK cells use invariant receptors to identify diseased cells, they nevertheless adapt to their environment, including the presence of certain MHC class I (MHC-I) molecules. This NK cell education, which is mediated by inhibitory receptors specific for MHC-I molecules, changes the responsiveness of activating NK cell receptors (licensing) and modifies the repertoire of MHC-I receptors used by NK cells. The fact that certain MHC-I receptors have the unusual capacity to recognize MHC-I molecules expressed by other cells (trans) and by the NK cell itself (cis) has raised the question regarding possible contributions of the two types of interactions to NK cell education. Although the analysis of an MHC-I receptor variant suggested a role for cis interaction for NK cell licensing, adoptive NK cell transfer experiments supported a key role for trans recognition. To reconcile some of these findings, we have analyzed the impact of cell type-specific deletion of an MHC-I molecule and of a novel MHC-I receptor variant on the education of murine NK cells when these mature under steady-state conditions in vivo. We find that MHC-I expression by NK cells (cis) and by T cells (trans), and MHC-I recognition in cis and in trans, are both needed for NK cell licensing. Unexpectedly, modifications of the MHC-I receptor repertoire are chiefly dependent on cis binding, which provides additional support for an essential role for this unconventional type of interaction for NK cell education. These data suggest that two separate functions of MHC-I receptors are needed to adapt NK cells to self-MHC-I. [ABSTRACT FROM AUTHOR]

Clonal deletion of autoreactive thymocytes is important for self-tolerance, but the intrathymic signals that induce clonal deletion have not been clearly identified. We now report that clonal deletion during negative selection required CD28-mediated costimulation of autoreactive thymocytes at the CD4+CD8lo intermediate stage of differentiation. Autoreactive thymocytes were prevented from undergoing clonal deletion by either a lack of CD28 costimulation or transgenic overexpression of the antiapoptotic factors Bcl-2 or Mcl-1, with surviving thymocytes differentiating into anergic CD4?CD8? double-negative thymocytes positive for the T cell antigen receptor ?? subtype (TCR??) that 'preferentially' migrated to the intestine, where they re-expressed CD8? and were sequestered as CD8??+ intraepithelial lymphocytes (IELs). Our study identifies costimulation by CD28 as the intrathymic signal required for clonal deletion and identifies CD8??+ IELs as the developmental fate of autoreactive thymocytes that survive negative selection. [ABSTRACT FROM AUTHOR]

Background concentrations of the heavy metals Mn, Ni, Cd, Co, Zn, Cu, and Pb in the soils and plant monitors of the Boatin Reserve were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Surface soil layers of the Boatin Reserve were polluted with Cu, as its concentration exceeded both the national legal standards and the content of Cu in nonpolluted areas. Analysis of heavy metals accumulation in all studied plant monitors indicated that the content of Cu, Pb, and Zn exceeded their concentration in non-polluted areas. It may be concluded that the heavy metals Cu, Pb, and Zn are the main pollutants in the Boatin Reserve. [ABSTRACT FROM AUTHOR]

Two Estonian populations of Dactylis glomerata and two of Puccinellia maritima were surveyed electrophoretically for eight enzymes to assess their diversity and affinity. Analysis of electrophoretic data indicated a significant amount of variability in the studied populations of D. glomerata and P. maritima as judged by the number of isoenzyme phenotypes and isoforms detected. Phenotypic affinity between D. glomerata and P. maritima was evaluated by calculating four coefficients of similarity/distance: SI, DCD, Ih, and DE. Phenetic analysis demonstrated that D. glomerata and P. maritima are more distantly positioned in comparison to other closely related grass species that share common genomes. Systematic position and affinity between Dactylis and Puccinellia within Poaceae are briefly discussed. [ABSTRACT FROM AUTHOR]

Polyacrylamide gel electrophoresis was employed to study the isoenzyme variation of esterase and acid phosphatase in natural populations of Dasypyrum villosum (L.) P.Candargy, Elytrigia repens (L.) Nevski and Elymus caninus (L.) L. Four similarity indices (SI, S, D, I[sub h]) were calculated in an attempt to evaluate quantitatively genetic affinities among the species examined. Considering index D, the species D. villosum proved to be equally distant (D = 0.17 in both cases) from the species pair Et. repens and El. caninus. The nearly twice lower value of D for the comparison between Et. repens and El. caninus is an indication of their stronger genetic relationship. Mean values of indices I[sub h], SI and S also indicated that D. villosum is the most distinct species within the group studied. The results were discussed in the light of chloroplast DNA sequence data, suggesting a close affinity among the genera Dasypyrum (Coss. & L. Durieu) T. Durand, Elytrigia Desv. and Elymus L. The results of the present isoenzyme study are not in congruence with cpDNA analysis. Both isoenzyme and DNA data suggest that the phylogenetic position of the genus Dasypyrum within the tribe Triticeae remains unresolved. [ABSTRACT FROM AUTHOR]

Steep terrain harvesting can only be implemented by a limited set of operational alternatives; therefore, it is important to be efficient in such conditions, in order to avoid incurring high costs. Harvesting abiotically-disturbed forests (salvage harvests caused by wet snow), which is becoming common these days, can significantly impact the operational efficiency of extraction operations. This study was implemented in order to evaluate the performance of truck-mounted uphill cable yarding operations in salvage logging deployed in coniferous stands. A time study was used to estimate the productivity and yarding costs, and predictive models were developed in order to relate the time consumption and productivity to the relevant operational factors, including the degree of wood damage. The average operational conditions were characterized by an extraction distance of 101 m and a lateral yarding distance of 18 m, resulting in a productivity rate of 20.1 m3 h−1. In response to different kind of delays, the productivity rate decreased to 12.8 m3 h−1. Under the prevailing conditions, lateral yarding accounted for 32% of the gross work cycle time, and for 50% of the delay-free work cycle time of the machine. Decreasing the lateral yarding distance and increasing the payload volume to the maximum capacity of the machine would eventually lead to a yarding productivity of close to 30 m3 per SMH (scheduled machine hour). The calculation of the gross costs of uphill yarding showed that the labor costs (35.7%) were slightly higher than the fixed costs (32.9%), and twice as high compared to the variable costs (17.7%). The remote control of the carriage, mechanical slack-pulling mechanisms, and radio-controlled chokers are just some of the improvements that would have led to increments in operational efficiency. [ABSTRACT FROM AUTHOR]

Activation of interleukin-1 (IL-1) receptor (IL-1R), Toll-like receptor 2 (TLR2), and TLR4 triggers NF-κB and mitogen-activated protein kinase (MAPK)-dependent signaling, thereby initiating immune responses. Tollip has been implicated as a negative regulator of NF-κB signaling triggered by these receptors in in vitro studies. Here, deficient mice were used to determine the physiological contribution of Tollip to immunity. NF-κB, as well as MAPK, signaling appeared normal in Tollip-deficient cells stimulated with IL-1β or the TLR4 ligand lipopolysaccharide (LPS). Similarly, IL-1β- and TLR-driven activation of dendritic cells and lymphocytes was indistinguishable from wild-type cells. In contrast, the production of the proinflammatory cytokines, IL-6 and tumor necrosis factor alpha was significantly reduced after IL-1β and LPS treatment at low doses but not at lethal doses of LPS. Tollip therefore controls the magnitude of inflammatory cytokine production in response to IL-1β and LPS. [ABSTRACT FROM AUTHOR]

The effector response of natural killer (NK) cells is determined by opposing signals received through activating and inhibitory receptors. A process termed NK cell education, which is guided by the recognition of Major Histocompatibility Complex class I (MHC-I) molecules, determines how efficiently activating receptors respond to stimulation. This ensures NK cell tolerance to healthy tissues while allowing robust responses to diseased host cells. It was thought that NK cells are educated during their development in the bone marrow and that education fixes the NK cells’ functional properties. However, recent findings suggest that the function of mature peripheral NK cells can adapt to changes in their environment and that the persistent exposure to normal-self is essential to maintain NK cell reactivity. Notwithstanding, NK cell stimulation in the context of inflammation can stably improve the functional properties of NK cells. [ABSTRACT FROM AUTHOR]

Protection against reinfection is mediated by Ag-specific memory CD8 T cells, which display stem cell-like function. Because canonical Wnt (Wingless/Int1) signals critically regulate renewal versus differentiation of adult stem cells, we evaluated Wnt signal transduction in CD8 T cells during an immune response to acute infection with lymphocytic choriomeningitis virus. Whereas naive CD8 T cells efficiently transduced Wnt signals, at the peak of the primary response to infection only a fraction of effector T cells retained signal transduction and the majority displayed strongly reduced Wnt activity. Reduced Wnt signaling was in part due to the downregulation of Tcf-1, one of the nuclear effectors of the pathway, and coincided with progress toward terminal differentiation. However, the correlation between low and high Wnt levels with short-lived and memory precursor effector cells, respectively, was incomplete. Adoptive transfer studies showed that low and high Wnt signaling did not influence cell survival but that Wnt high effectors yielded memory cells with enhanced proliferative potential and stronger protective capacity. Likewise, following adoptive transfer and rechallenge, memory cells with high Wnt levels displayed increased recall expansion, compared with memory cells with low Wnt signaling, which were preferentially effector-like memory cells, including tissue-resident memory cells. Thus, canonical Wnt signaling identifies CD8 T cells with enhanced proliferative potential in part independent of commonly used cell surface markers to discriminate effector and memory T cell subpopulations. Interventions that maintain Wnt signaling may thus improve the formation of functional CD8 T cell memory during vaccination. [ABSTRACT FROM AUTHOR]

The BCR-ABL1 fusion protein is the cause of chronic myeloid leukemia (CML) and of a significant fraction of adult-onset B cell acute lymphoblastic leukemia (B-ALL) cases. Using mouse models and patient-derived samples, we identified an essential role for γ-catenin in the initiation and maintenance of BCR-ABL1+ B-ALL but not CML. The selectivity was explained by a partial γ-catenin dependence of MYC expression together with the susceptibility of B-ALL, but not CML, to reduced MYC levels. MYC and γ-catenin enabled B-ALL maintenance by augmenting BIRC5 and enforced BIRC5 expression overcame γ-catenin loss. Since γ-catenin was dispensable for normal hematopoiesis, these lineage- and disease-specific features of canonical Wnt signaling identified a potential therapeutic target for the treatment of BCR-ABL1+ B-ALL. • Maintenance of BCR-ABL1+ B-ALL depends on γ-catenin (Junction plakoglobin) • γ-Catenin and β-catenin play selective roles in BCR-ABL1+ B-ALL and CML, respectively • MYC and BIRC5 (Survivin) are essential targets of γ-catenin in BCR-ABL1+ B-ALL • ABL kinase inhibitor-resistant B-ALL cells are susceptible to γ-catenin suppression Luong-Gardiol et al. show that Wnt pathway activity mediated by γ-catenin is critical for BCR-ABL1+ B-ALL, in contrast to β-catenin being important in CML. B-ALL is more sensitive to partial reduction of MYC expression level than CML, and γ-catenin regulates the expression of MYC and Survivin in B-ALL. [ABSTRACT FROM AUTHOR]