Search Results (192)

Oceanic mesoscale activity influences the atmosphere in the southwestern and southern sectors of the Atlantic Ocean. However, the influence of high latitudes, specifically sea ice, on mid-latitudes and a better understanding of mesoscale ocean–atmosphere thermodynamic interactions still require further study. To quantify the effects of oceanic mesoscale activity during the periods of maximum and minimum Antarctic sea ice extent (September 2019 and February 2020), numerical experiments were conducted using a coupled regional model and an online two-dimensional spatial filter to remove high-frequency sea surface temperature (SST) oscillations. The largest SST anomalies were observed in the Brazil–Malvinas Confluence and along oceanic fronts in September, with maximum SST anomalies reaching 4.23 °C and −3.71 °C. In February, the anomalies were 2.18 °C and −3.06 °C. The influence of oceanic mesoscale activity was evident in surface atmospheric variables, with larger anomalies also observed in September. This influence led to changes in the vertical structure of the atmosphere, affecting the development of the marine atmospheric boundary layer (MABL) and influencing the free atmosphere above the MABL. Modulations in precipitation patterns were observed, not only in oceanic regions, but also in adjacent continental areas. This research provides a novel perspective on ocean–atmosphere thermodynamic coupling, highlighting the mesoscale role and importance of its representation in the study region. Full article

With the natural evolution of the Arctic route and advancements in related technologies, the development of new green ice-class ships is becoming a key technological breakthrough for the global shipbuilding industry. As a special vessel form that must perform icebreaking operations and undertake long-distance ocean voyages, an ice-class ship requires sufficient icebreaking capacity to navigate ice-covered water areas. However, since such ships operate for most of their time under open water conditions, it is also crucial to consider their resistance characteristics in these environments. Firstly, this paper employs linear interpolation to extract wind, wave, and sea ice data along the route and calculates the proportion of ice-covered and open water area in the overall voyage. This provides data support for hull form optimization based on real sea state conditions. Then, a resistance optimization platform for ice-class ships is established by integrating hull surface mixed deformation control within a scenario analysis framework. Based on the optimization results, comparative analysis is conducted between the parent hull and the optimized hull under various environmental resistance scenarios. Finally, the optimization results are evaluated in terms of energy consumption using a fuel consumption model of the ship’s main engine. The optimized hull achieves a 16.921% reduction in total resistance, with calm water resistance and wave-added resistance reduced by 5.92% and 27.6%, respectively. Additionally, the optimized hull shows significant resistance reductions under multiple wave and floating ice conditions. At the design speed, calm water power and hourly fuel consumption are reduced by 7.1% and 7.02%, respectively. The experimental results show that the hull form optimization process in this paper can take into account both ice-region navigation and ice-free navigation. The design ideas and solution methods can provide a reference for the design of ice-class ships. Full article

Background and Objectives: Due to the progress made in all areas of research, pediatric patients diagnosed with acute lymphoblastic leukemia (ALL) now have an average overall survival rate of 90%. There are still discrepancies between high-income countries and limited-resource centers. The aim of this study was to analyze prognostic factors and outcome parameters in a 223-patient cohort from a single center in Romania, treated with two adapted BFM protocols. Materials and Methods: The patients diagnosed with ALL in our center were enrolled in this study from January 2016 to December 2022 and subsequently followed up until December 2024. The patients were treated first according to the ALL IC BFM 2009 protocol until June 2019 and afterwards with the ALL AIEOP BFM 2017 protocol starting with July 2019. The prognostic factors were analyzed in both subgroups and the outcomes were measured: event-free survival (EFS), overall survival (OS), cumulative incidence of relapse (CIR), relapse-free survival (RFS) and non-relapse mortality (NRM). Results: The comparison between the two subgroups revealed that every parameter improved over time: complete remission after induction (87.75% vs. 80.7%), early deaths (3.92% vs. 5.78%), deaths in remission (4.08% vs. 5.26%), 5-year EFS (73.79% vs. 70.22%), 5-year CIR (18.36% vs. 19.04%), 5-year RFS (81.76% vs. 80.97%), 5-year NRM (7.85% vs. 10.77%), and 5-year OS (88.18% vs. 82.54%). Whereas for the standard-risk group, events such as relapse or death were isolated, for intermediate-risk patients, the events were limited to a small number and did not significantly influence the overall results, and for high-risk children, the results improved significantly between the two subgroups. The worst outcomes were observed in patients with the BCR::ABL1 fusion gene, T-cell phenotype, and in teenagers, compared to the ETV6::RUNX1 fusion gene, B precursor ALL, and in smaller children, respectively. Conclusions: The 5-year OS increased in our center from 82.54% to almost 90%, with the most substantial finding being the survival rate for high-risk patients, now reaching up to 80%. The prognostic factors were age at diagnosis, genetic characteristics, and response to treatment, especially prednisone sensibility. Full article

Titanium dioxide nanoparticles (TiO₂-NPs) were synthesized using the molten salt method and systematically characterized. TiO₂-NPs were evaluated for their capacity to promote the growth of Capsicum annuum cultivars together with the plant growth-promoting microorganisms (PGPMs) Bacillus thuringiensis (Bt) and Trichoderma harzianum (Th). The variables analyzed included physiological parameters and antioxidant responses. The capacity of TiO₂-NPs to scavenge free radicals was also investigated, along with their biocompatibility, using Artemia salina as an in vivo model. The results demonstrated that TiO₂-NPs exhibited a nanocuboid-type morphology, negative surface charge, and small surface area. It was noted that TiO₂-NPs enhanced the CFU and spore production of Bt (1.56–2.92 × 10⁸ CFU/mL) and Th (2.50–3.90 × 10⁸ spores/mL), respectively. It was observed that TiO₂-NPs could scavenge DPPH, ABTS, and H₂O₂ radicals (IC₅₀ 48.66–109.94 μg/mL), while not compromising the viability of A. salina at 50–300 μg/mL. TiO₂-NPs were determined to enhance the root length and fresh and dry weights of chili peppers. Similarly, TiO₂-NPs in synergy with Bt and Th increased the activity of β-1,3-Glucanase (2.45 nkat/g FW) and peroxidase (69.90 UA/g FW) enzyme activity, and increased the TPC (29.50 GA/g FW). The synergy of TiO₂-NPs with the PGPMs consortium also upregulated the total chlorophyll content: 210.8 ± 11.4 mg/mg FW. The evidence from this study unveils the beneficial application of TiO₂-NPs with Bt and Th as an efficient approach to promote the physiology and antioxidant responses of chili peppers. Full article

Environmentally friendly extraction technologies for biologically active substances (BASs) are an actively developing and important industry. In recent years, the development of this area has been associated with the use of low-melting mixtures, which are most often referred to as “deep eutectic solvents”. Vaccinium vitis-idaea L. is a valuable source of phenolic biologically active compounds. However, to date, there are limited studies devoted to the use of such solvents for the extraction of biologically active substances from V. vitis-idaea. This study introduces the use of low-melting mixtures of choline chloride or betaine with lactic acid and water for the ultrasonic extraction of phenolic secondary metabolites from V. vitis-idaea leaves for the first time. The kinetics of extraction have been studied, and the extraction conditions have been optimized using a Box–Behnken design. It was found that the optimal extraction conditions are follow: the most suitable mixture is betaine with lactic acid and water at a molar ratio of 1:10:5, the optimal temperature is 33 °C, and the optimal ratio of the mass of plant material to the volume of the solvent is 1:20. Under these conditions, the yield of total phenolic compounds was 744.3 ± 1.2 mg GAE/g, and total flavonoids reached 24.4 ± 0.2 mg RE/g. The IC₅₀ values of the obtained extract were 2.45 mg/mL for free radical scavenging with DPPH and 3.47 mg/mL for ABTS. The data obtained can be used in the development of green technologies for the extraction of biologically active substances from the leaves of V. vitis-idaea. Full article

Background/Objectives: Glioblastoma represents a particularly aggressive and fatal type of brain tumor. Peptide-drug conjugates, which offer the promise of traversing the blood-brain barrier to selectively accumulate in tumor tissues and precisely target cancer cells, are an active area of research. We present the synthesis and characterization of the T7 peptide (HAIYPRH) as a targeting ligand for the transferrin receptor, which is highly expressed on both the blood-brain barrier and glioma cells. Methods: Using the T7 peptide, the synthesis, characterization, and biological evaluation of a transferrin receptor-targeted, combination SN-38 and rucaparib peptide drug conjugate (T7-SN-38-rucaparib) are described. Results: The T7 peptide drug conjugate readily cleaved in the presence of exogenous cathepsin B, releasing the active drug payloads. In vitro experiments demonstrated potent cytotoxic effects of the T7 peptide drug conjugate on glioblastoma cells (IC₅₀ = 22.27 nM), with reduced toxicity to non-cancerous HEK 293 cells (IC₅₀ = 115.78 nM), indicating selective toxicity toward cancer cells. Further investigations revealed that blocking transferrin receptors with drug-free T7 peptide significantly reduced the conjugate’s cytotoxicity, an effect that could be reversed by introducing exogenous cathepsin B to the cells. Conclusions: These findings highlight the potential of glioblastoma-targeted delivery of SN-38 and rucaparib based on specific recognition of the transferrin receptor for transport across the blood-brain barrier, offering the prospect of reduced toxicity and selective killing of cancer cells. Additionally, since rucaparib does not cross the blood-brain barrier, this work is significant to facilitate the use of rucaparib for the treatment of brain tumors. Full article

Assessment of Programmed Death-Ligand 1 (PD-L1) immunohistochemical (IHC) expression on tumor cells (TCs) and immune cells (ICs) in bladder cancer (BC) is challenging. Artificial Intelligence (AI) has potential for accurate PD-L1 IHC scoring, but its efficiency remains debatable. Our aim was to compare two AI protocols provided by the free QuPath software (v0.5.1) (Selected Area Interpretation (AI-SAI) and Whole Slide Imaging (AI-WSI)) with manual PD-L1 IHC scoring. A total of 43 BCs were included. PD-L1 IHC was performed using the SP263 clone. The IHC slides were digitized and further imported into QuPath. The PD-L1 positivity threshold was set at 25%. Statistically significant correlations were observed between AI-SAI and manual interpretation for both TCs (r = 0.85) and ICs (r = 0.57). AI-WSI yielded comparable results, with correlation coefficients of r = 0.82 for TCs and r = 0.56 for ICs. However, AI-SAI demonstrated stronger agreement with manual assessment (κ = 0.86) compared to AI-WSI (κ = 0.65). Receiver Operating Characteristic (ROC) analysis further supported the superiority of AI-SAI, with higher AUC values for both TCs (0.96 vs. 0.92) and ICs (0.92 vs. 0.90). Our findings indicate that AI-SAI is preferable to AI-WSI, particularly in BC cases with high PD-L1-positive TC content. Nevertheless, supervision by an experienced pathologist is mandatory. Full article

Seafloor communities along the eastern Svalbard coast remain poorly studied. To address this gap, we sampled benthic organisms on the soft sediments of Storfjord in 2017 and 2019, a large fjord predominantly influenced by cold Arctic waters, to study the local fauna and identify the key environmental drivers shaping community structure. In total, 314 taxa were recorded, with an increase in abundance (from 3923 to 8977 ind. m⁻², mean 6090 ind. m⁻²) and a decline in biomass (ranging from 265 to 104 g m⁻², mean 188 g m⁻²) toward the outer part of the fjord. However, no clear spatial trends were observed for alpha diversity (approximately 100 species per 0.3 m²) or the Shannon index (mean 3 per station). The primary factors influencing benthic abundance were the duration of the ice-free period (IFP) and the degree of siltation (DS), both of which are proxies for trophic conditions. The prevailing taxa displayed a high tolerance to temperature fluctuations and seasonal variability in nutrient inputs. Benthic biomass showed a negative relationship with IFP, DS, and water depth, but it was positively correlated with the proportion of fine-grained sediment. The Yoldia hyperborea community (mean abundance: 3700 ind. m⁻², mean biomass: 227 g m⁻²) was associated with Arctic waters characterized by higher inorganic suspension loads. In contrast, areas with reduced or weaker sedimentation were dominated by the communities of Maldane sarsi (6212 ind m⁻², 226 g m⁻²) and Maldane sarsi + Nemertini g.sp. (5568 ind m⁻², 165 g m⁻²). The Spiochaetopterus typicus community (7824 ind m⁻², 139 g m⁻²) was observed in areas under moderate influence of Atlantic waters, characterized by low sedimentation rates and increased fresh detritus flux. Full article

Background/Objectives: Non-small cell lung cancer (NSCLC) constitutes over 84% of all lung cancer cases and is a leading cause of cancer-related mortality globally. Alectinib, a second-generation anaplastic lymphoma kinase (ALK) inhibitor, is effective in ALK-positive NSCLC; however, its clinical potential is hampered by poor aqueous solubility and limited oral bioavailability. This study aimed to develop Alectinib-loaded chitosan–alginate nanoparticles (ACANPs) to enhance its solubility, oral bioavailability, and therapeutic efficacy. Methods: ACANPs were synthesized using a novel combined solid/oil/water (s/o/w) emulsification technique with ionotropic gelation. Characterization was performed using Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), dynamic light scattering (DLS), and zeta potential measurements. A validated high-performance liquid chromatography (HPLC) method quantified the Alectinib. In vitro drug release studies compared free Alectinib with ACANPs. Cytotoxicity against NSCLC cell lines (A549 and H460) was assessed using MTT assays. Pharmacokinetic parameters were evaluated in rats using LC–MS/MS. Results: ACANPs showed a high encapsulation efficiency (~97%), an average particle size of 161 nm, and a positive zeta potential of +21 mV. In vitro release studies revealed a threefold increase in drug release from ACANPs over 48 h compared to free Alectinib. Cytotoxicity assays demonstrated significantly reduced IC₅₀ values for ACANPs. Pharmacokinetic analyses showed an enhanced maximum plasma concentration (C_max) and area under the curve (AUC), indicating a 78% increase in oral bioavailability. Conclusions: ACANPs substantially improved the solubility, cytotoxic efficacy, and oral bioavailability of Alectinib, suggesting their potential as a promising nanocarrier system for enhancing NSCLC treatment outcomes. Full article

Background and Methods: We assessed the prokaryotic and eukaryotic diversity present in non-vegetated and vegetated soils on King George Island, Maritime Antarctic, in combination with measurements of carbon dioxide fluxes. Results: For prokaryotes, 381 amplicon sequence variants (ASVs) were assigned, dominated by the phyla Actinobacteriota, Acidobacteriota, Pseudomonadota, Chloroflexota, and Verrucomicrobiota. A total of 432 eukaryotic ASVs were assigned, including representatives from seven kingdoms and 21 phyla. Fungi dominated the eukaryotic communities, followed by Viridiplantae. Non-vegetated soils had higher diversity indices compared with vegetated soils. The dominant prokaryotic ASV in non-vegetated soils was Pyrinomonadaceae sp., while Pseudarthrobacter sp. dominated vegetated soils. Mortierella antarctica (Fungi) and Meyerella sp. (Viridiplantae) were dominant eukaryotic taxa in the non-vegetated soils, while Lachnum sp. (Fungi) and Polytrichaceae sp. (Viridiplantae) were dominant in the vegetated soils. Measured CO₂ fluxes indicated that the net ecosystem exchange values measured in vegetated soils were lower than ecosystem respiration in non-vegetated soils. However, the total flux values indicated that the region displayed positive ecosystem respiration values, suggesting that the soils may represent a source of CO₂ in the atmosphere. Conclusions: Our study revealed the presence of rich and complex communities of prokaryotic and eukaryotic organisms in both soil types. Although non-vegetated soils demonstrated the highest levels of diversity, they had lower CO₂ fluxes than vegetated soils, likely reflecting the significant biomass of photosynthetically active plants (mainly dense moss carpets) and their resident organisms. The greater diversity detected in exposed soils may influence future changes in CO₂ flux in the studied region, for which comparisons of non-vegetated and vegetated soils with different microbial diversities are needed. This reinforces the necessity for studies to monitor the impact of resident biota on CO₂ flux in different areas of Maritime Antarctica, a region strongly impacted by climatic changes. Full article

Background/Objectives: Recently, the prevalence of diseases such as diabetes, arthritis, and inflammatory diseases, along with their complications, has become a significant health problem. This is in addition to the various biomedical applications of pyrazole, isatin, and indole derivatives. Accordingly, cooperation will continue between chemistry scientists, pharmaceutical scientists, and human doctors to produce hybrid compounds from pyrazole with isatin or indole possessing biological activities as anti-diabetic, anti-arthritic, and anti-inflammatory agents. Methods: The two series of pyrazole–isatin conjugates 12a–h and pyrazole–indole conjugates 14a–d were prepared from our previous works via the direct reaction of 5-amino-pyrazoles 10a–d with N-alkyl isatin 11a,b, and 1H-indole-3-carbaldehyde (13), respectively, using the previously reported procedure. The potential biological activities of 12a–h and 14a–d as anti-diabetic, anti-arthritic, and anti-inflammatory agents were assessed through estimated inhibition percentage (%) and the median inhibitory concentrations (IC₅₀) using methods described in the literature. Further, the computational assessments of 12a–h and 14a–d such as toxic doses (the median lethal dose, LD₅₀), toxicity classes, drug-likeness model scores (DLMS), molecular lipophilicity potential (MLP) maps, polar surface area (PSA) maps, and topological polar surface area (TPSA) values were predicted using available free websites. Results: The in vitro enzymatic assessment results showed that pyrazole–indole conjugate 14b possesses powerful activities against (i) α-amylase (% = 65.74 ± 0.23, IC₅₀ = 4.21 ± 0.03 µg/mL) and α-glucosidase (% = 55.49 ± 0.23, IC₅₀ = 2.76 ± 0.01 µg/mL); (ii) the protein denaturation enzyme (% = 49.30 ± 0.17) and against the proteinase enzyme (% = 46.55 ± 0.17) with an IC₅₀ value of 6.77 ± 0.01 µg/mL; (iii) the COX-1, COX-2, and 5-LOX enzymes with an IC₅₀ of 5.44 ± 0.03, 5.37 ± 0.04, and 7.52 ± 0.04, respectively, which is almost close to the IC₅₀ of the indomethacin and zileuton drugs. Also, the computational assessment results showed (i) the conjugate 14b possesses lipophilic surface properties thus can cross cell membranes, and is effective for treatment; (ii) all the conjugates possess a TPSA value of more than 140 Ų thus possess good intestinal absorption. Conclusions: The two series of pyrazole–isatin conjugates 12a–h and pyrazole–indole conjugates 14a–d were synthesized from our previous works. The results of these in vitro enzymatic and computational assessments concluded that the pyrazole–indole conjugate 14b possesses powerful activities against various studied enzymes and possesses good computational results. In the future, our research team will present in vitro, in vivo biological, and computational assessments to hopefully obtain effectual agents such as anti-diabetic, anti-arthritic, and anti-inflammatory. Full article

Icebergs pose significant risks to shipping, offshore oil exploration, and underwater pipelines. Detecting and monitoring icebergs in the North Atlantic Ocean, where darkness and cloud cover are frequent, is particularly challenging. Synthetic aperture radar (SAR) serves as a powerful tool to overcome these difficulties. In this paper, we propose a method for automatically detecting and classifying icebergs in various sea conditions using C-band dual-polarimetric images from the RADARSAT Constellation Mission (RCM) collected throughout 2022 and 2023 across different seasons from the east coast of Canada. This method classifies SAR imagery into four distinct classes: open water (OW), which represents areas of water free of icebergs; open water with target (OWT), where icebergs are present within open water; sea ice (SI), consisting of ice-covered regions without any icebergs; and sea ice with target (SIT), where icebergs are embedded within sea ice. Our approach integrates statistical features capturing subtle patterns in RCM imagery with high-dimensional features extracted using a pre-trained Vision Transformer (ViT), further augmented by climate parameters. These features are classified using XGBoost to achieve precise differentiation between these classes. The proposed method achieves a low false positive rate of 1% for each class and a missed detection rate ranging from 0.02% for OWT to 0.04% for SI and SIT, along with an overall accuracy of 96.5% and an area under curve (AUC) value close to 1. Additionally, when the classes were merged for target detection (combining SI with OW and SIT with OWT), the model demonstrated an even higher accuracy of 98.9%. These results highlight the robustness and reliability of our method for large-scale iceberg detection along the east coast of Canada. Full article

The information interaction characteristics of connected vehicles are distinct from those of non-connected vehicles, thereby exerting an influence on the conventional traffic flow model. The original lane-changing model for non-connected vehicles is no longer applicable in the context of the new traffic flow environment. The modelling of the new hybrid traffic flow, comprising both connected and ordinary vehicles, is set to be a pivotal research topic in the coming years. The objective of this paper is to present a methodology for optimal mixed traffic flow dynamic modelling and cooperative control in intelligent and connected environments (ICE). The study utilizes the real-time perception and information interaction of connected vehicles for traffic information, taking into account the access characteristics of both connected and non-connected vehicles. The satisfaction-based free lane-changing and mandatory lane-changing models of connected vehicles are designed. Secondly, a mixed traffic flow lane-changing model based on influence characteristics is constructed for the influence area of connected vehicles. This model takes into account the degree of influence that connected vehicles have on non-connected vehicles, with different distances being considered respectively. Subsequently, a vehicle guidance strategy for mixed traffic flows comprising grid-connected and conventional vehicles is proposed. A variety of speed guidance scenarios are considered, with an in-depth analysis of the speed optimization of connected vehicles and the movement law of non-connected vehicles. This comprehensive analysis forms the foundation for the development of a vehicle guidance strategy for mixed traffic flows, with the overarching objective being to minimize the average delay of vehicles. In order to evaluate the effectiveness of the proposed method, the intersection of Gaota Road and Fangshui North Street in Yanqing District, Beijing, has been selected for analysis. The results of the study demonstrate that by modifying the density of the mixed traffic flow, the overall average speed of the mixed traffic flow declines as the density of vehicles increases. The findings reported in this study reflect the role of connected vehicles in enhancing road capacity, maximizing intersection capacity and mitigating the occurrence of queuing phenomena, and improving travel speed through the mixed traffic flow lane-changing model based on impact characteristics. This study also provides some guidance for future control of the mixed traffic flow formed by emergency vehicles and social vehicles and for realizing a smart city. Full article

Inland river ships navigating in an ice area cannot avoid contact between the propeller and ice block. In addition to ensuring the safety of propeller blades, the fatigue strength of the propulsion shaft system under ice load excitation must also be considered. This paper first studies how to calculate the natural frequency of free torsional vibration of the system, then uses Newmark integral programing to calculate the maximum torsional stress of shaft system under ice load at resonance speed. Low cycle stress and high cycle stress are studied according to fatigue analysis theory. The method of determining S–N curve and ice load stress spectrum is given and the cumulative damage ratio is calculated based on Palmgren–Miner linear cumulative damage theory. Finally, taking a real inland river vessel propulsion shaft system as an example, the fatigue strength of the shaft system under different working conditions of ice load excitation is studied. Therefore, this study has practical significance and engineering application value in conducting fatigue research on the propulsion shaft system of an inland waterway vessel sailing in an ice area. Full article

Precambrian tropical glaciation is an enigma of Earth’s climate. Overlooking fundamental difference of land/sea icelines, it was equated with a global frozen ocean, which is at odds with the sedimentary evidence of an active hydrological cycle, and its genesis via the runaway ice–albedo feedback conflicts with the mostly ice-free Proterozoic when its trigger threshold was well exceeded by the dimmer sun. In view of these shortfalls, I put forth two key hypotheses of the tropical glaciation: first, if seeded by mountain glaciers, the land ice would advance on sea level to be halted by above-freezing summer temperature, which thus abuts an open cozonal ocean; second, a tropical supercontinent would block the brighter tropical sun to cause the required cooling. To test these hypotheses, I formulate a minimal tropical/polar box model to examine the temperature response to a varying tropical land area and show that tropical glaciation is indeed plausible when the landmass is concentrated in the tropics despite uncertain model parameters. In addition, given the chronology of paleogeography, the model may explain the observed deep time climate to provide a unified account of the faint young Sun paradox, Precambrian tropical glaciations, and Phanerozoic glacio-epochs, reinforcing, therefore, the uniformitarian principle. Full article