Search Results (2,494)

This study evaluates the role of groundwater in the dynamics of the Slano blato landslide using hydrogeochemical and stable isotope data. Results show that deep groundwater inflow significantly affected the landslide behavior, as demonstrated by pronounced hydrogeochemical and isotopic differences among springs. Springs within the landslide differ markedly from those in similar geological settings of the Vipava Valley, indicating a distinct local groundwater system. Groundwater is present within the landslide body even during dry periods. Waters originate mainly from a higher karstic recharge area and flow through deep flysch strata, particularly fractured sandstones, where they become enriched in dissolved ions, especially K⁺ and SO₄²⁻, and show increased mineralization in the lower parts of the landslide. Saturation indices indicate slight oversaturation with calcite and dolomite and equilibrium with quartz for most samples, reflecting interaction with carbonates and flysch sandstones. Elevated sulphate concentrations and near-equilibrium conditions for mirabilite and thenardite suggest salt-related deterioration of landslide material, enhanced by evaporation. Stable isotope data (δ¹³C_DIC, δ¹⁸O, δ²H) indicate dominant carbonate recharge, meteoric origin, evaporation effects, and long-term water–rock interaction. This study highlights the need for additional isotope tracers, groundwater age indicators, seasonal monitoring, and on-site meteorological measurements to improve interpretation. Full article

Recent discoveries of fluorite–barite deposits in the Donghai–Linshu area in northern Jiangsu Province, China, underscore the region’s mineral potential, yet detailed geological investigations remain limited. In this study, we examined monzonite and quartz monzonite from drill cores in the Jiashan mining area using petrography, U–Pb zircon dating, zircon trace element geochemistry, whole-rock geochemistry, and zircon Lu–Hf isotopes. Laser ablation inductively coupled plasma mass spectrometry (LA–ICP–MS) zircon U–Pb analyses were conducted to constrain the crystallization ages of the monzonite (127.06 ± 0.54 Ma and 126.83 ± 0.75 Ma) and quartz monzonite (127.2 ± 0.5 Ma and 128.59 ± 0.62 Ma) to the Early Cretaceous, marking a significant magmatic event. Many of the zircons contain inherited Neoproterozoic cores (718–760 Ma and 800–860 Ma), indicating the assimilation of deep crustal materials of this age. The monzonite is metaluminous, with moderate SiO₂ (61.61–62.41 wt.%), high alkalis (Na₂O + K₂O = 7.48–7.92 wt.%), and A/CNK = 0.72–0.91. The quartz monzonite has higher SiO₂ (66.26–68.18 wt.%) and alkalis (8.32–9.33 wt.%). Both rock types exhibit similar trace and rare earth element patterns: enrichment in large-ion lithophile and light rare earth elements, depletions in Nb, Ta, and Ti, no significant Zr-Hf depletion, and weak negative Eu anomalies (δEu ≈ 0.84–1.00). Their low Zr + Nb + Ce + Y contents, Ga/Al ratios, and TFeO/MgO ratios indicate that they have an I-type granite affinity. The Early Cretaceous zircons have highly negative ε_Hf(t) values (−33.7 to −23.5) and ancient two-stage model ages (2622–3247 Ma), which are consistent with derivation from Archean crust. The inherited Neoproterozoic zircons have younger Paleo–Mesoproterozoic T_DM2 ages. The evidence suggests that both intrusions were mainly generated by partial melting of ancient Archean basement, with minor mantle input. The magma generation was likely triggered by crustal anatexis induced by the underplating of mantle-derived magmas in an extensional tectonic regime, coeval with Early Cretaceous magmatism in the Sulu orogen. Full article

In this study, we investigated the bioaccumulation of 17 heavy metals—titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, arsenic, selenium, molybdenum, antimony, cadmium, tin, mercury, and lead—in the liver and kidney tissues of the least weasel, based on samples (n = 129) collected from adjacent intensive agricultural environments in Hungary and Austria. To explore the structure of the bioaccumulation data, principal component analysis (PCA) was performed. The PCA score plot based on national-level elemental profiles revealed no differentiation between Austria and Hungary. In contrast, a clear and unambiguous distinction was observed between the two examined tissues within individuals for Ti, Mn, Fe, Co, Zn, Se, Mo, Cd, and Hg (p < 0.001), as well as for Pb (p < 0.05). The biological relevance of the accumulation results was adjusted using the MCID approach. As heavy metal accumulation in the least weasel has not yet been investigated, our results could only be compared with concentrations reported for predatory mammals occurring in similar habitats. Based on the relevant literature, we highlight predominantly anthropogenic exposure pathways affecting agroecosystems—organic and mineral fertilizers, plant protection products, wastewater, and fossil fuels—which underscore the necessity of regular biomonitoring studies in agricultural landscapes. Full article

Reactive transport in porous media exists ubiquitously in natural and industrial systems—reformation of geological energy repository, carbon dioxide (CO${}_2$) sequestration, CO${}_2$ storage via mineralization, and soil remediation are just some examples where geo-/bio-chemical reactions play a key role. Reactive transport models are expected to provide assessments of (1) the effective property variation and (2) the reaction capability. However, the synergy among flow, solute transport, and reaction undermines the predictability of the existing model. In recent decades, the Micro-Continuum Approach (MCA) has demonstrated advantages for modeling pore-scale reactive transport and high accuracy compared with experiments. In this study, we present an MCA-based numerical framework that simulates dissolution/erosion or precipitation in digital rocks. The framework imports two- or three-dimensional digital rock samples, conducts reactive transport simulations, and evaluates dynamic changes in porosity, surface area, permeability tensor, tortuosity, mass change, and reaction rate. The results show that samples with similar effective properties, e.g., porosity or permeability, may exhibit different reaction abilities, suggesting that the pore-scale geometry has a strong impact on reactive transport. Additionally, the numerical framework demonstrates the advantage of conducting multiple reaction studies on the same sample, in contrast to reality, where there is often only one physical experiment. This advantage enables the identification of the optimal condition, quantified by the dimensionless P$\acute{\mathrm{e}}$clet number and Damk$\ddot{\mathrm{o}}$hler number, to reach the maximum reaction. We believe that the newly developed framework serves as a toolbox for evaluating reactivity capacity and predicting effective properties of digital samples. Full article

Peak bone mass gained in youth is crucial for preventing osteoporosis. Artistic gymnastics (AG) is highly osteogenic, yet its long-term effects on adults ≥ 45 years are not well documented. This case–control study compared bone mineral density (BMD) and the prevalence of osteopenia/osteoporosis in former gymnasts, age-matched controls, and reference populations from Brazil and Portugal. Participants included 65 former gymnasts (32 males, 33 females; 45–84 years), who trained for 12.6 ± 4.3 years and included 41 international competitors, and 91 controls (37 males; 45–87 years). Whole-body and femoral BMD were assessed by DXA. Physical activity during youth (10–20 years) (PA-Youth) and the past decade (PA-10) was recorded. Reference data were drawn from large cohorts in Brazil (FIBRA, n = 828) and Portugal (CIAFEL, n = 1089). Former gymnasts had substantially higher PA-Youth than controls, while PA-10 was similar. Gymnasts displayed 4–6 times higher femoral Z-scores (neck and total) and a markedly lower prevalence of osteopenia/osteoporosis (males: 3% vs. 16%; females: 36% vs. 52%, p < 0.05). These benefits remained after adjustment for age, PA-10, and hormonal/calcium therapy. Relative to reference populations, gymnasts showed greater whole-body and femoral mineralization, with no osteoporosis cases (vs. 6–12% overall; 9–13% among those ≥60 years). Age-stratified analysis (45–59 and ≥60 years) revealed a consistently lower osteopenia prevalence across age groups, except in females ≥ 60 years. In conclusion, early-life AG participation is associated with enduring skeletal benefits, including higher bone mineralization and reduced osteopenia/osteoporosis in adults ≥ 45 years. The protective effect appears diminished in older females, likely reflecting prolonged postmenopausal bone loss. Full article

Accurate lithologic maps derived from satellite imagery underpin structural interpretation, mineral exploration, and geohazard assessment. However, automated mapping in complex terranes remains challenging because spectrally similar units, narrow anisotropic bodies, and ambiguous contacts can degrade boundary fidelity. In this study, we propose SegNeXt-HFCA, a hierarchical multiscale fusion network with coordinate attention for lithologic segmentation from a Sentinel-2/DEM feature stack. The model builds on SegNeXt and introduces a hierarchical multiscale encoder with coordinate attention to jointly capture fine textures and scene-level structure. It further adopts a class-frequency-aware hybrid loss that combines boundary-weighted online hard-example mining cross-entropy with Lovász-Softmax to better handle long-tailed classes and ambiguous contacts. In addition, we employ a robust training and inference scheme, including entropy-guided patch sampling, exponential moving average of parameters, test-time augmentation, and a DenseCRF-based post-refinement. Two study areas in the Beishan orogen, northwestern China (Huitongshan and Xingxingxia), are used to evaluate the method with a unified 10-channel Sentinel-2/DEM feature stack. Compared with U-NetFormer, PSPNet, DeepLabV3+, DANet, LGMSFNet, SegFormer, BiSeNetV2, and the SegNeXt backbone, SegNeXt-HFCA improves mean intersection-over-union (mIoU) by about 3.8% in Huitongshan and 2.6% in Xingxingxia, respectively, and increases mean pixel accuracy by approximately 3–4%. Qualitative analyses show that the proposed framework better preserves thin-unit continuity, clarifies lithologic contacts, and reduces salt-and-pepper noise, yielding geologically more plausible maps. These results demonstrate that hierarchical multiscale fusion with coordinate attention, together with class- and boundary-aware optimization, provides a practical route to robust lithologic mapping in structurally complex regions. Full article

Groundwater, a critical resource for regional water security and public health, faces escalating threats from heavy metal contamination—a pressing environmental challenge worldwide. This study focuses on the central-south Hunan region of China, a mineral-rich, densely populated area characterized predominantly by non-point-source pollution, aiming to systematically unravel the spatial patterns, source contributions, and associated health risks of heavy metals in local groundwater. Based on 717 spring and well water samples collected in 2024, we determined pH and seven heavy metals (As, Cd, Pb, Zn, Fe, Mn, and Tl). By integrating hydrogeological zoning, lithology, topography, and river networks, the study area was divided into 11 assessment units, clearly revealing the spatial heterogeneity of heavy metals. The results demonstrate that exceedances of Cd, Pb, and Zn were sporadic and point-source-influenced, whereas As, Fe, Mn, and Tl showed regional exceedance patterns (e.g., Mn exceeded the standard in 9.76% of samples), identifying them as priority control elements. The spatial distribution of heavy metals was governed the synergistic effects of lithology, water–rock interactions, and hydrological structure, showing a distinct “acidic in the northeast, alkaline in the southwest” pH gradient. Combined application of the APCS-MLR and PMF models resolved five principal pollution sources: an acid-reducing-environment-driven release source (contributing 76.1% of Fe and 58.3% of Pb); a geogenic–anthropogenic composite source (contributing 81.0% of Tl and 62.4% of Cd); a human-perturbation-triggered natural Mn release source (contributing 94.8% of Mn); an agricultural-activity-related input source (contributing 60.1% of Zn); and a primary geological source (contributing 89.9% of As). Monte Carlo simulation-based health risk assessment indicated that the average hazard index (HI) and total carcinogenic risk (TCR) for all heavy metals were below acceptable thresholds, suggesting generally manageable risk. However, As was the dominant contributor to both non-carcinogenic and carcinogenic risks, with its carcinogenic risk exceeding the threshold in up to 3.84% of the simulated adult exposures under extreme scenarios. Sensitivity analysis identified exposure duration (ED) as the most influential parameter governing risk outcomes. In conclusion, we recommend implementing spatially differentiated management strategies: prioritizing As control in red-bed and granite–metamorphic zones; enhancing Tl monitoring in the northern and northeastern granite-rich areas, particularly downstream of the Mishui River; and regulating land use in brick-factory-dense riparian zones to mitigate disturbance-induced Mn release—for instance, through the enforcement of setback requirements and targeted groundwater monitoring programs. This study provides a scientific foundation for the sustainable management and safety assurance of groundwater resources in regions with similar geological and anthropogenic settings. Full article

The solid structure of industrial sinter comprises seven mineral associations (A, B, C, D, Ds, E, N) which have different relative abundances of key minerals, textures and spatial relationships to micro-macropores and hematite nuclei. Among the key characteristics of the mineral associations: (MA), MA-A comprises abundant SFCA-I microplates with hematite; MA-B consists of disseminated fine-grained magnetite in a network of SFCA-III microplates; MA-C is similar to MA-B but contains patches of dendritic SFCA-III with larnite and minor glass; MA-D comprises magnetite surrounded by coarse prisms of SFCA within glass; MA-Ds, a subtype of MA-D, includes SFCA with secondary skeletal hematite; MA-E consists of anhedral to skeletal magnetite or hematite in a matrix of glass; and MA-N comprises unmelted hematite nuclei from iron ore feedstock. SFCA-III and SFCA-I are dominant in MA-B and MA-A, respectively, whilst magnetite is the most common mineral in MA-C, MA-D/Ds and MA-E. Low-temperature sintering samples are largely of MA-A to MA-D (62 area %), which contain higher combined levels of SFCA-SFCA-III and lower levels of magnetite-dominant MA-E (12.6 area %), whereas high-temperature/magnetite sintering examples had high levels of magnetite-dominant MA-E (31.6 area %) and MA-D/Ds (52.1 area %) and low levels of MA-A to MA-C (8.9 area %). It is proposed that the formation of each MA is controlled by the peak sintering temperature attained, the dwell time at higher temperature which adversely allows fractional crystallisation to tie up more Fe in magnetite rather than forming SFCA phases during cooling, and especially a slower rate of cooling which promotes the formation of more SFCA family phases at lower temperatures. However, local variations in chemistry inherited from raw material granulation and assimilation during sintering of Si-rich gangue or ore nuclei are also important. Full article

Boron is a critical strategic mineral resource. Boron deposits in the Liaodong region currently supply more than 35% of China’s domestic demand. To advance exploration efforts in this area, detailed physical property measurements were carried out on various rock formations within the Yingkou–Anshan district. Utilizing integrated geophysical approaches, including gravity, magnetic, and electrical surveys, this study introduced—for the first time—the wide field electromagnetic method (WFEM) for deep exploration testing. Measured parameters included density, magnetic susceptibility, and resistivity. The electromagnetic methods proved effective in boron mineral exploration due to their pronounced response over the Lieryu Formation, which is enriched in boron minerals. We refined inversion parameters to improve the consistency between geophysical models and actual geological characteristics by correlating physical property parameters with drilled core lithology. Comprehensive analysis indicates that boron mineralization in the Houxianyu mining area is not restricted to the Lieryu Formation. Significant boron enrichment also occurs in deeper structures, including thick granite bodies, large-scale folds, and various unconformity contacts. These deep mineralized bodies share similar physical properties with known ore deposits but exhibit distinct geochemical signatures. Through integrated interpretation of gravity, magnetic, and electrical profiles—combined with geological, mineralogical, and structural data from the Houxianyu area—it is evident that ore bodies in the study area occupy structurally complex positions, influenced by regional tectonic evolution and magmatic activity. Geophysical results further reveal a notable deep extension of mineralization, indicating promising potential for deep prospecting. Full article

The study evaluated the effects of nitrogen fertilization on the morphogenetic, structural, productive, and nutritional characteristics of Brachiaria brizantha cv. Paiaguás subjected to two stockpiling periods in a pot experiment. The experiment was conducted using a randomized block design in a 4 × 2 factorial arrangement, with four nitrogen doses (0, 25, 50, and 75 mg N dm⁻³, applied as urea) and two stockpiling periods (80 and 120 days). Increasing nitrogen doses promoted linear increases in leaf appearance, elongation, and senescence rates, as well as tiller population density, while reducing phyllochron and leaf lifespan. Forage mass increased linearly with nitrogen, ranging from 96.25 to 113.00 g of dry matter per pot, and leaf blade mass showed a similar response. Root mass exhibited a quadratic response, with a maximum estimated value of 49.33 g pot⁻¹ at 60.18 mg N dm⁻³, this quadratic equation explained 96% of the variation in the results. No significant interaction was observed between nitrogen doses and stockpiling periods for dry matter, crude protein, mineral matter, or neutral detergent fiber contents. However, nitrogen fertilization increased crude protein content across plant fractions, with leaf crude protein rising from about 70 to over 110 g kg⁻¹ dry matter. Nitrogen fertilization at 75 mg N dm⁻³ combined with an 80-day stockpiling period improves canopy structure, forage production, and nutritional quality of Paiaguás grass, highlighting the importance of synchronizing nitrogen supply with deferment duration in deferred pasture management. Full article

Aronia melanocarpa, a plant with nutrient-rich fruits, with application in the food and pharmaceutical industry, has been extensively investigated but, nevertheless, the exploration of the secondary metabolites profile from its by-products remains quite limited. The main objective of this study was to evaluate the possibility of using some different natural mineral waters from Romania, as green solvents, for the extraction of bioactive compounds from aronia stems and fruits by applying eco-compatible working techniques (maceration for 24 h, and ultrasonication at room temperature and 50 °C for 30 min). The effect of five natural mineral waters (one with medium and four with low mineral content) on the extraction capacity and phytochemical profile of stems and fruits’ extracts was monitored using fast and efficient analysis techniques (electrochemical, spectroscopic, and chromatographic) and compared with that of classical solvents. The results showed that, in the case of stems, extraction by maceration was, for all types of water used, the most efficient, followed by ultrasonication at room temperature. Also, at the same time, in most cases, all mineral waters showed better performance than distilled water, and the highest efficiency of the extraction process was recorded for natural water with a medium mineralization level. The similarity observed in the phytochemical profiles of aqueous extracts from the aronia stems and the fruits highlights both the potential of this by-product as a source of bioactive compounds and the efficiency of natural mineral waters as green extraction solvents. Full article

The accelerated carbonation of fresh concrete and recycled aggregates is one of the safest methods of CO₂ sequestration as it mineralizes CO₂, preventing its escape into the atmosphere. CO₂ injection during batching of concrete improves its strength and may partially replace Portland cement, as with supplementary cementitious materials (SCMs). The curing of concrete by incorporation of CO₂ also accelerates early strength development, which may enable early stripping of formwork/moulds for precast and in situ construction. The carbonation process may also be used for the beneficiation of recycled aggregates sourced from demolition waste. The CO₂ mineralization technique may also be used for producing low-carbon, carbon-neutral, or carbon-negative concrete constituents via the carbonation of mineral feedstock, including industrial wastes like steel slag, mine tailings, or raw quarried minerals. This research paper analyses various available technologies for CO₂ storage in concrete, CO₂ curing and mixing of concrete, and CO₂ injection for improving the properties of recycled aggregates. Carbon dioxide can be incorporated into concrete both through reaction with hydrating cement and through incorporation in recycled aggregates, giving a product of similar properties to concrete made from virgin materials. In this contribution we explore the various methodologies available to incorporate CO₂ in both hydrating cement and recycled aggregates and develop a protocol for best practice. We find that the loss of concrete strength due to the incorporation of recycled aggregates can be mitigated by CO₂ curing of the aggregates and the hydrating concrete, giving no negative strength consequences and sequestering around 30 kg of CO₂ per cubic metre of concrete. Full article

Quinoa (Chenopodium quinoa Willd.) is increasingly valued as a climate-resilient crop due to its nutritional quality and adaptability; however, there is limited information on the nutritional composition of heat-tolerant genotypes grown in tropical environments or the potential of quinoa leaves as an additional nutrient source. This study assessed the nutritional composition of leaves and grains from three heat-tolerant quinoa genotypes (Ames 13746 (Pison), Ames 13748 (Copacabana), and Ames 13745 (Kaslae)) to support their use as multipurpose crops in warm regions. Crude protein, amino acid, dietary fiber fraction, total fat, total starch, and mineral (Ca, Mg, P, K, Fe, and Zn) concentrations were quantified using AOAC, AACCI, and AOCS standardized methods. The grains exhibited a balanced essential amino acid profile, with lysine concentrations exceeding those of most staple cereals. The protein contents in the leaves and grains did not differ among genotypes (p > 0.05), although combustion analysis yielded consistently higher values than the Kjeldahl method. The leaves differed significantly in insoluble and total dietary fiber (p < 0.05), with Kaslae presenting the highest levels. In grains, the dietary fiber, total fat, total starch, and mineral contents did not vary among genotypes. The leaf mineral composition differed in terms of Ca and P, while Mg, Fe, K, and Zn levels remained similar across genotypes. These findings underscore quinoa’s potential as a nutrient-dense, multipurpose crop for food production in tropical environments. Full article

Dendrobium officinale Kimura et Migo (D. officinale) is a traditional Chinese medicinal herb with recognized anti-inflammatory, antioxidant, and immunomodulatory properties. This study evaluated whether dietary supplementation with D. officinale leaf powder could influence bone mass, mechanical strength, and molecular markers of bone metabolism in caged laying hens. A total of 192 healthy 19-week-old Jinghong No. 1 hens were randomly assigned to three dietary groups: a control group fed a basal diet and two treatment groups supplemented with 1200 or 3600 mg/kg of D. officinale leaf powder for 16 weeks. Tibial and femoral bone strength and mineral density did not differ significantly among treatments (p > 0.05). However, tibial breaking strength displayed upward trends in both supplemented groups (p = 0.08), and similar tendencies were observed for femoral bone mineral content and bone density (p = 0.08). At the molecular level, dietary supplementation produced selective changes in gene expression. The low-dose diet significantly increased VEGFA expression (p < 0.05), whereas the high-dose diet resulted in significantly higher TGF-β1 expression (p < 0.05). Several other genes related to bone formation, bone resorption, or cytokine signaling exhibited numerical increases but did not reach statistical significance. These findings indicate that D. officinale leaf powder may modulate bone metabolic processes at the transcriptional level, although these molecular alterations were not accompanied by significant improvements in bone mass. Full article

Background: Irisin, a muscle-derived hormone, enhances the energy metabolism by activating the brown adipose tissue and acts as a bone-forming agent across the entire life span. No consistent clinical data in humans have been published so far to highlight if blood irisin as glucose/bone biomarker should be refined based on the vitamin D status (deficient or sufficient). Therefore, we aimed to objectively assess the level of irisin in female adults with abnormal and normal vitamin D status, as reflected by the level of 25-hydroxyvitamin (25OHD) in relationship with glucose and bone metabolic parameters. Methods: This pilot, prospective, exploratory study included eighty-nine menopausal women aged over 50. We excluded subjects with malignancies, bone and metabolic disorders, insulin treatment, and active endocrine disorders. Fasting profile included glycaemia, insulin, and glycated haemoglobin A1c (HbA1c). Then, 75 g oral glucose tolerance test (OGTT) included glycaemia and insulin assay after 60 and 120 min. Bone status involved bone turnover markers and central dual-energy X-ray absorptiometry providing bone mineral density (BMD) and trabecular bone score. Results: Eighty-nine subjects were included in the following two groups depending on 25OHD: vitamin D-deficient (VDD) group (N = 48; 25OHD < 30 ng/mL) and vitamin D-sufficient (VDS) group (N = 41; 25OHD ≥ 30 ng/mL). The two groups had similar age and menopausal period (62.29 ± 10.19 vs. 63.56 ± 8.16 years, respectively; 15.82 ± 9.55 vs. 16.11 ± 9.00 years, p > 0.5 for each). A statistically significant higher body mass index (BMI) was found in VDD vs. VDS group (32.25 ± 5.9 vs. 28.93 ± 4.97 kg/m², p = 0.006). Circulating irisin was similar between the groups as follows: median (IQR) of 91.85 (44.76–121.76) vs. 71.17 (38.76–97.43) ng/mL, p = 0.506. Fasting profile and OGTT assays showed no between-group difference. Median HOMA-IR in VDD group pointed out insulin resistance of 2.67 (1.31–3.29). Lowest mean/median T-scores at DXA for both groups were consistent with osteopenia category, but they were confirmed at different central sites as follows: femoral neck in both groups [VDD versus VDS group: −1.1 (−1.20–−0.90) vs. −1.1 (−1.49–−0.91), p = 0.526, respectively], only at lumbar spine for VDS group (T-score of −1.18 ± 1.13). The correlations between irisin and the mentioned parameters displayed a different profile when the analysis was performed in the groups with different 25OHD levels. In VDD group, irisin levels statistically significantly correlated with serum phosphorus (r = −0.32, p = 0.022), osteocalcin (r = −0.293, p = 0.038), P1NP (r = −0.297, p = 0.04), HbA1c (r = 0.342, p = 0.014), and BMI (r = 0.408, p = 0.003). Conclusions: This pilot study brings awareness in the analysis of irisin in relationship with glucose and bone-related biomarkers correlates, showing a distinct type of association depending on 25OHD level, which might represent an important crossroad in the multitude of irisin-activated signal transduction pathways. Full article