Search Results (642)

Resurrection plants such as Ramonda serbica and Ramonda nathaliae are gaining scientific attention due to their exceptional ability to withstand extreme drought and cold. This study is the first to evaluate the changes in photosynthetic activity, antioxidant defense, and the role of protective proteins during the early hours of recovery of these species after freezing-induced desiccation. Specimens collected from natural habitats where temperatures dropped below −10 °C were rehydrated under controlled conditions, and measurements were taken at multiple time points from 1 h up to 7 days after recovery. Both species demonstrated a gradual increase in photosynthesis, with the CO₂ assimilation rate significantly improving after 24 h and reaching full restoration by day 7. This recovery aligned with increases in relative water content and stomatal conductance. Photosystem II efficiency was fully restored within 72 h. Notably, R. nathaliae exhibited higher thermal dissipation during stress than R. serbica. Antioxidant activity peaked between 1 and 3 h of rehydration and returned to baseline by day 7. Additionally, early rehydration stages triggered the accumulation of stress-related proteins such as dehydrins, early light-inducible proteins, small heat shock proteins, and fatty acid amide hydrolase. These results provide valuable insights into the desiccation–rehydration mechanisms of Ramonda species, demonstrating that they fully recover physiological functions within seven days and highlighting species-specific stress responses during early rehydration. Full article

Our previous research has demonstrated the role of optimal temperatures and reactive oxygen species (ROS) in maintaining symptomless nonhost resistance (NHR) of barley to powdery mildews. However, the exact functions of temperature and ROS in NHR of plants, including barley, to viral infections are not known. Although barley is a nonhost for Tobacco mosaic virus (TMV), this virus can replicate in barley leaves at temperatures of ca. 30 °C. Here we elucidated the influence of short-term heat stress pre-treatments (30 °C, 3 h; heat shock at 49 °C, 20 s) on the symptomless NHR of barley to TMV and the role of the ROS superoxide (O₂^.−) in maintaining NHR. Heat stress and antioxidant (superoxide dismutase and catalase, SOD + CAT) treatments resulted in 50–100% higher TMV levels, while combined heat shock and SOD + CAT application caused further increases in TMV and appearance of cell and tissue death resembling a hypersensitive response (HR). An early (from 2 h after inoculation) burst of O₂^.− was essentially absent in TMV-infected barley exposed to short-term heat stress pre-treatments. Expression of barley genes regulating ROS (O₂^.−) metabolism (HvRBOHF2, HvSOD1) and cell death (HvBI-1) displayed an inverse correlation with TMV levels even at later time points (1–4 days after inoculation), implying a role in symptomless NHR, while increased levels of the antioxidant glutathione marked heat stress-induced suppression of NHR. We demonstrated that short-term heat stress and antioxidant treatments result in compromised NHR of barley to TMV, pointing to the role of optimal temperatures and ROS (O₂^.−) in symptomless NHR to virus infections. Full article

The typical structure of an oblique detonation wave (ODW) consists of a leading shock wave followed by a coupled shock-flame complex. The distance from the leading shock’s originating point to the ignition onset is referred to as the induction length. This work numerically studies the induction length effect using a two-step induction-reaction kinetic model. Results reveal that the induction length governs the transition pattern of ODWs. By testing four distinct induction lengths, four ODW regimes are identified, including a prompt ODW, a delayed smooth ODW, a delayed abrupt ODW, and a delayed abrupt ODW with an upstream triple point in oscillatory motion. The mechanisms behind these regimes are analyzed in detail. Additionally, hysteresis is observed when the induction length decreases from a larger value, demonstrating that this phenomenon can be influenced by the kinetic process. Full article

Parasitoids exhibit remarkable abilities to manipulate host physiology, ensuring offspring survival and development. This study investigated the molecular mechanisms underlying how the parasitoid Cotesia chilonis modulates cold tolerance in its host, the rice stem borer Chilo suppressalis, using transcriptome sequencing. We found that the host larvae’s supercooling point was lowest at 3 days post-parasitism but increased significantly by day 4. Transcriptome analysis identified 507 differentially expressed genes (DEGs), including 235 up-regulated by parasitism. Functional enrichment revealed that these DEGs were primarily associated with ribosome biogenesis, protein processing in the endoplasmic reticulum (ER), and oxidative phosphorylation under parasitism stress. Notably, 24 DEGs linked to temperature tolerance were predominantly heat shock proteins (HSPs) and calcium signaling-related genes. The reliability of transcriptome data was confirmed via RT-qPCR for eight randomly selected DEGs. Functional assays demonstrated that parasitism stress significantly inhibited ER activity. However, HSP expression did not significantly affect ER activity or cytosolic Ca²⁺ concentration in the hemolymph cells of C. suppressalis larvae. This research provides insights into the complex physiological and molecular mechanisms through which C. suppressalis responds to parasitism stress, particularly concerning cold tolerance modulation. Full article

To accurately assess the residual stress distribution on the superficial layer of the weld for a pure copper butt-welded joint after laser shock peening (LSP), a coupled model was established by integrating experimental measurements with numerical simulations. This model simulates both the tungsten inert gas (TIG) welding process of pure copper and the subsequent LSP treatment applied to the weld. On this basis, the effects of the spot overlapping rate, number of impact layers, and pulse width on the weld residual stress profile were evaluated via multi-point LSP simulations. The findings imply that LSP converts the weld’s superficial residual stress from tensile to compressive, which verifies the accuracy of the simulations through the experimental data. Multi-point LSP numerical simulations demonstrate that elevating the spot overlapping rate and number of impact layers enhances the amplitude and affected depth of the surface compressive residual stress (CRS). A slight decrease in the CRS on the superficial layer of the weld was observed with an increase in pulse width. Compared with increasing the overlapping rate and pulse width, increasing the number of impact layers has a more significant strengthening effect. When the impact layer reached 3 times, the surface CRS reached −219.4 MPa, and the influence depth was 1.3 mm. Full article

Background/Objectives: Rice production faces threats from rising temperatures, demanding thermotolerant varieties. This study characterizes transcriptomic dynamics and identifies Hsp101-1 (heat shock protein 101-1)-associated gene regulatory modules in rice under reproductive-stage heat stress. Methods: Transcriptomics and WGCNA (weighted gene co-expression network analysis) were conducted in flag leaves and spikelets for wild-type (WT) and Hsp101-1-overexpressing (OE) lines under 40 °C stress at six time points (0–24 h) to reveal the change in gene expressions. Results: The number of DEGs (differentially expressed genes) revealed substantial pre-existing differences in WT and OE lines. Pre treatment, OE flag leaves showed 545 upregulated and 676 downregulated DEGs versus WT leaves. Post heat shock, the number of DEGs in flag leaves and spikelets was significantly reduced by 70–80%. KEGG enrichment of common DEGs across time points showed both WT and OE flag leaves enriched for ribosome biogenesis, ribosomes, and chaperones/folding catalysts. WGCNA identified that the MEdarkslateblue module correlated negatively with WT and positively with OE flag leaves. The MEturquoise module was suppressed at 1 h but activated by 8 h. Spikelet analysis identified the MElightpink4 module (negative correlation with WT, positive with OE) and a similarly dynamic MEturquoise module. Venn analysis identified 76 shared module genes, 71 of which were upregulated in the OE line, indicating that Hsp101-1 activates common protective targets. Hsp101-1’s expression in the WT line was low basally, significantly upregulated at 1–8 h post shock, and returned to low levels by 24 h. Conclusions: Hsp101-1 enhances thermotolerance by (1) constitutively pre-stabilizing transcriptomic networks and reducing transcriptional fluctuations under heat stress and (2) modularly coordinating tissue-specific responses, providing a climate resilience framework. Full article

We present a curated, openly accessible dataset of 71 regional meteor events simultaneously recorded by optical and infrasound instrumentation between 2006 and 2011. These events were captured during an observational campaign using the all-sky cameras of the Southern Ontario Meteor Network and the co-located Elginfield Infrasound Array. Each entry provides optical trajectory measurements, infrasound waveforms, and atmospheric specification profiles. The integration of optical and acoustic data enables robust linkage between observed acoustic signals and specific points along meteor trajectories, offering new opportunities to examine shock wave generation, propagation, and energy deposition processes. This release fills a critical observational gap by providing the first validated, openly accessible archive of simultaneous optical–infrasound meteor observations that supports trajectory reconstruction, acoustic propagation modeling, and energy deposition analyses. By making these data openly available in a structured format, this work establishes a durable reference resource that advances reproducibility, fosters cross-disciplinary research, and underpins future developments in meteor physics, atmospheric acoustics, and planetary defense. Full article

The integration of three-dimensional inward-turning inlets with airframes has broad application prospects. This paper develops an integrated design method for the inlet forebody with a controllable incident shock wave shape, aiming at the three-dimensional inward-turning inlet with a circular entrance, and it is applied to the forebody design of a given inward-turning inlet to obtain a three-dimensional inward-turning inlet/forebody matching scheme. Numerical simulation and wind tunnel experiment were carried out to investigate the aerodynamic performance of the inlet. The results show that the inlet/forebody matching scheme successfully realizes both geometric and aerodynamic matching between the inlet and forebody, resulting in a shock-on-lip condition at the design point, with only a 2% reduction in mass flow rate. This indicates that the forebody design and matching method are highly effective. It should be noted that after the forebody matching is achieved, the overall compression effect of the inlet on the airflow is weakened, and both the Mach number and total pressure at the inlet outlet increase slightly. Full article

In a warming world, mechanisms, such as the heat shock response, which plays a role in the recovery from or tolerance towards heat stress, are of increasing importance. Certain heat shock protein genes (hsps) have previously been shown to be highly inducible in several paper wasp species during high temperature stress under laboratory conditions. Here, we sought to investigate how hsps are expressed under natural daily temperature fluctuations by collecting broods from wild nests of two species of paper wasps (Polistes dominula, P. nimpha). We collected them at 06:00 and 16:00, the expected low and high points in daily hsp expression, and measured the expression of three hsps (hsp70, hsp83, hsc70). We found that the nest temperature in July could reach temperatures that result in a large upregulation of hsp expression in the laboratory. Under natural conditions, however, we found that the induction response was much more moderate and limited to the larvae. The pupae showed no response to the daily fluctuating temperature and had a constant expression similar to that of larvae in the afternoon. The similarities and differences between natural and laboratory hsp expressions highlight the importance of field studies, as they add valuable context when interpreting laboratory results. Full article

Background: Enkephalins are endogenous opioid peptides that modulate cardiovascular and renal function and are overexpressed in patients with acute heart failure (AHF). Although biologically active enkephalins lack a favorable biomarker profile, their stable surrogate proenkephalin 119–159 (PENK) appears to display prognostic value in AHF settings. The aim of the present study was to evaluate the role of point-of-care (POC) PENK in predicting mortality and worsening renal function (WRF) in patients presenting to the emergency department (ED) with AHF. Methods: In this single-center observational study, 107 patients presenting to the ED with AHF were prospectively enrolled. We measured PENK levels upon ED presentation with a commercially available POC immunoassay and investigated their association with WRF within 48 h and all-cause mortality during a 1-year follow-up. Results: The patients had a mean age of 72 ± 13 years, and 58% were men. Moreover, 62% had acutely decompensated chronic heart failure (HF), 24% had pulmonary edema, 9% had cardiogenic shock, and 5% had right HF. The median PENK levels were 111 [60–193] pmol/L. PENK was independently associated with WRF (adjusted OR, 95% CI: 15.4 [2.0–120.2]; p = 0.009), with levels of ≥90.5 pmol/L identified as the optimal cut-off for predicting WRF (AUC: 0.690; p < 0.001). PENK was also an independent predictor of short- and long-term all-cause mortality, with an optimal cut-off of ≥95.8 pmol/L (AUC for 30-day, 90-day, and 1-year mortality: 0.717, 0.723, and 0.724, respectively; all p < 0.001). Conclusions: In patients presenting to the ED with AHF, POC PENK may serve as an early prognostic marker of WRF and short- and long-term mortality. Full article

The geometric symmetry of the pipeline constitutes a critical determinant in regulating the energy propagation dynamics during the explosion process. In the present study, a transparent plexiglass pipe experimental system incorporating a range of angles (30° to 150°) was meticulously constructed. Leveraging high-frequency pressure sensors in conjunction with high-speed camera technology, this investigation examines the influence of the pipe angle, which disrupts geometric symmetry, on the coupling explosion of gas and coal dust. The experimental findings illustrate that an increase in the pipeline turning angle significantly enhances the velocity of the explosion flame front (with the maximum velocity escalating from 97.92 m/s to 361.28 m/s) and concurrently reduces the total propagation time (from 71 ms to 56.5 ms). Moreover, there is a notable reduction in the duration of the explosion flame, decreasing from 240.5 ms to 64.17 ms at the coal dust deposition point. The peak overpressure of the shock wave exhibits a significant increase with the augmentation of the turning angle (rising from 7.07 kPa at 30° to 88.40 kPa at 150°). Furthermore, the overpressure in the fore section of the turning is amplified, attributable to the superimposition of reflected waves and turbulent effects. This study elucidates critical mechanisms including turbulence-enhanced combustion, secondary dust generation from coal dust, and energy dissipation resulting from abrupt alterations in pipeline geometry, thereby offering a theoretical framework for the prevention and effective emergency management of coal mine explosion disasters. Full article

Thermal stimulation represents an effective method for enhancing reservoir permeability, thereby improving geothermal energy recovery in Enhanced Geothermal Systems (EGS). The phase-field method (PFM) has been widely adopted for its proven capability in modeling the fracture behavior of brittle solids. Consequently, a coupled thermo-mechanical phase-field model (TM-PFM) was developed in COMSOL 6.2 Multiphysics to probe thermal fracturing mechanisms in reservoir rocks. The TM-PFM was validated against the analytical solutions for the temperature and stress fields under steady-state heat conduction in a thin-walled cylinder, three-point bending tests, and thermal shock tests. Subsequently, two distinct thermal fracturing modes in reservoir rock under high-temperature conditions were investigated: (i) fracture initiation driven by sharp temperature gradients during instantaneous thermal shocks, and (ii) crack propagation resulting from heterogeneous thermal expansion of constituent minerals. The proposed TM-PFM has been validated through systematic comparison between the simulation results and the corresponding experimental data, thereby demonstrating its capability to accurately simulate thermal fracturing. These findings provide mechanistic insights for optimizing geothermal energy extraction in EGS. Full article

This paper examines the changing role of emissions trading systems (ETSs) within the macro-financial framework of energy markets, emphasizing price dynamics and systemic spillovers. Utilizing monthly data from seven ETS jurisdictions spanning January 2021 to December 2024 (N = 287 observations after log transformation and first differencing), which includes four auction-based markets (United States, Canada, United Kingdom, South Korea), two secondary markets (China, New Zealand), and a government-set fixed-price scheme (Germany), this research estimates a panel vector autoregression (PVAR) employing a Common Correlated Effects (CCE) model and augments it with machine learning analysis utilizing XGBoost and explainable AI methodologies. The PVAR-CEE reveals numerous unexpected findings related to carbon markets: ETS returns exhibit persistence with an autoregressive coefficient of −0.137 after a four-month lag, while increasing inflation results in rising ETS after the same period. Furthermore, ETSs generate spillover effects in the real economy, as elevated ETSs today forecast a 0.125-point reduction in unemployment one month later and a 0.0173 increase in inflation after two months. Impulse response analysis indicates that exogenous shocks, including Brent oil prices, policy uncertainty, and financial volatility, are swiftly assimilated by ETS pricing, with effects dissipating completely within three to eight months. XGBoost models ascertain that policy uncertainty and Brent oil prices are the most significant predictors of one-month-ahead ETSs, whereas ESG factors are relevant only beyond certain thresholds and in conditions of low policy uncertainty. These findings establish ETS markets as dynamic transmitters of macroeconomic signals, influencing energy management, labor changes, and sustainable finance under carbon pricing frameworks. Full article

Background: Acute kidney injury (AKI) frequently occurs following major liver resection, adversely affecting both short- and long-term outcomes. This study aimed to determine the incidence of AKI post-hepatectomy and identify relevant pre- and intraoperative risk factors. Our secondary objectives were to develop a predictive score for postoperative AKI and assess the associations between AKI, chronic kidney disease (CKD), and 1-year mortality. Methods: This was a retrospective study in a cancer referral center in Marseille, France, from 2018 to 2022. Results: Among 169 patients, 55 (32.5%) experienced AKI. Multivariate analysis revealed several independent risk factors for postoperative AKI, including age, body mass index, the use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, time to liver resection, intraoperative shock, and bile duct reconstruction. Neoadjuvant chemotherapy was protective. The AKIMEBO score was developed, with a threshold of ≥15.6, demonstrating a sensitivity of 89.5%, specificity of 76.4%, positive predictive value of 61.8%, and negative predictive value of 94.4%. AKI was associated with increased postoperative morbidity and one-year mortality following major hepatectomy. Conclusion: AKI is a common complication post-hepatectomy. Factors such as time to liver resection and intraoperative shock management present potential clinical intervention points. The AKIMEBO score can provide a valuable tool for postoperative risk stratification. Full article

Background and Objectives: Severe sepsis complicated by refractory shock is associated with high mortality. Adding continuous hemofiltration to venovenous extracorporeal membrane oxygenation (ECMO) may accelerate clearance of inflammatory mediators and improve haemodynamic stability, but evidence remains limited. We analysed 44 consecutive septic-shock patients treated with combined ECMO-hemofiltration (ECMO group) and compared them with 92 septic-shock patients managed without ECMO or renal replacement therapy (non-ECMO group). Methods: This retrospective single-centre study reviewed adults admitted between January 2018 and March 2025. Demographic, haemodynamic, laboratory and outcome data were extracted from electronic records. Primary outcome was 28-day mortality; secondary outcomes included intensive-care-unit (ICU) length-of-stay, vasopressor-free days, and change in Sequential Organ Failure Assessment (SOFA) score at 72 h. Results: Baseline age (49.2 ± 15.3 vs. 52.6 ± 16.1 years; p = 0.28) and APACHE II (27.8 ± 5.7 vs. 26.9 ± 6.0; p = 0.41) were comparable. At 24 h, mean arterial pressure rose from 52.3 ± 7.4 mmHg to 67.8 ± 9.1 mmHg in the ECMO group (mean change [∆] + 15.5 mmHg, p < 0.001). Controls exhibited a modest 4.9 mmHg rise that did not reach statistical significance (p = 0.07). Inflammatory markers decreased more sharply with ECMO (IL-6 ∆ −778 pg mL⁻¹ vs. −248 pg mL⁻¹, p < 0.001). SOFA fell by 3.6 ± 2.2 points with ECMO versus 1.6 ± 2.4 in controls (p = 0.01). Twenty-eight-day mortality did not differ (40.9% vs. 48.9%, p = 0.43), but ICU stay was longer with ECMO (median 12.5 vs. 9.3 days, p = 0.002). ΔIL-6 correlated with ΔSOFA (ρ = 0.46, p = 0.004). Conclusions: ECMO-assisted hemofiltration improved early haemodynamics and organ-failure scores and accelerated cytokine clearance, although crude mortality remained unchanged. Larger prospective trials are warranted to clarify survival benefit and optimal patient selection. Full article