Direct Response Research Articles

Effects of focused ultrasound in a “clean” mouse model of ultrasonic neuromodulation

Recent studies on ultrasonic neuromodulation (UNM) in rodents have shown that focused ultrasound (FUS) can activate peripheral auditory pathways, leading to off-target and brain-wide excitation, which obscures the direct activation of the target area by FUS. To address this issue, we developed a new mouse model, the double transgenic Pou4f3+/DTR×Thy1-GCaMP6s, which allows for inducible deafening using diphtheria toxin and minimizes off-target effects of UNM while allowing effects on neural activity to be visualized with fluorescent calcium imaging. Using this model, we found that the auditory confounds caused by FUS can be significantly reduced or eliminated within a certain pressure range. At higher pressures, FUS can result in focal fluorescence dips at the target, elicit non-auditory sensory confounds, and damage tissue, leading to spreading depolarization. Under the acoustic conditions we tested, we did not observe direct calcium responses in the mouse cortex. Our findings provide a cleaner animal model for UNM and sonogenetics research, establish a parameter range within which off-target effects are confidently avoided, and reveal the non-auditory side effects of higher-pressure stimulation.

Non-stomatal processes are responsible for the decrease in gross primary production of a potato crop during edaphic drought

Soil water stress is one of the main constraints on agrosystem functioning, causing a reduction in gross primary production (GPP). It is a key factor for the selection of drought-tolerant plant varieties and the adaptation of irrigation management strategies. Therefore, identifying the physiological factors limiting GPP is crucial. Land surface models commonly implement a beta (β) stress function to reproduce the effects of drought on GPP. It is still unclear whether GPP limitations originate from a direct stomatal response (SOL) or from other non-stomatal causes (NSOL). Moreover, the shape and thresholds of the β function are a major cause of uncertainty in LSMs. This study investigated the effects of edaphic drought on GPP limitations of a potato crop by using eddy covariance data from the Lonzée ICOS station (BE-Lon) in Belgium for four years (2006, 2010, 2014 and 2018) and by calibrating the β function on NSOL and SOL.The decrease in the relative extractable water in the soil (REW) induced a decline in the apparent maximum carboxylation rate (NSOL) from similar REW thresholds for all growing seasons of potato crops. A sensitivity analysis showed that the non-inclusion of REW decrease on NSOL in the modeling of GPP led to important overestimations of carbon sequestration from a threshold corresponding to 46 % of the maximum available soil water. The stomatal sensitivity to photosynthesis (SOL) remained constant or even increased in 2010 and 2018. The carbon and water fluxes were decoupled when REW decreased, exhibiting a strict control of NSOL on hourly dynamics of GPP. This study provides REW thresholds to identify drought stress episodes and to help for designing irrigation management strategies. Our results advocate for a better representation of the influence of drought on photosynthesis processes of potato crops to improve the accuracy of model predictions during drought.

Homeostatic Control of Deep Sleep and Molecular Correlates of Sleep Pressure in Drosophila.

Homeostatic control of sleep is typically addressed through mechanical stimulation-induced forced wakefulness and the measurement of subsequent increases in sleep. A major confound attends this approach: biological responses to deprivation may reflect a direct response to the mechanical insult rather than to the loss of sleep. Similar confounds accompany all forms of sleep deprivation and represent a major challenge to the field. Here we describe a new paradigm for sleep deprivation in Drosophila that fully accounts for sleep-independent effects. Our results reveal that deep sleep states are the primary target of homeostatic control and establish the presence of multi-cycle sleep rebound following deprivation. Furthermore, we establish that specific deprivation of deep sleep state results in state-specific homeostatic rebound. Finally, by accounting for the molecular effects of mechanical stimulation during deprivation experiments, we show that serotonin levels track sleep pressure in the fly's central brain. Our results illustrate the critical need to control for sleep-independent effects of deprivation when examining the molecular correlates of sleep pressure and call for a critical reassessment of work that has not accounted for such non-specific effects.

Design and Assessment of a Novel Approach for Ecosystem Warming Experiments in High‐Energy Tidal Wetlands

AbstractCoastal salt marshes have an important role in climate change adaptation and mitigation. Direct and indirect responses to warming are expected to vary along the marsh elevation gradient, making ecosystem responses to warming at this marine‐terrestrial ecotone uncertain. The Marsh Ecosystem Response to Increased Temperatures (MERIT) experiment was established in 2018 on the North Sea coast of Germany. Experimental plots are evenly distributed over three elevational marsh zones (pioneer, low marsh, and high marsh) and include three temperature treatments (ambient, +1.5°C, +3.0°C). MERIT's novel design combines active warming (horizontal surface warming cables and vertical soil warming pins) with passive, partially covered domes. For performance assessment, temperature deltas between ambient and warmed plots were calculated and evaluated at seasonal, daily, and diurnal timescales. We used Linear Mixed Models with Residual Maximum Likelihood for evaluating warming treatment effects and constraining environmental factors. MERIT was effective at ecosystem warming in this high‐energy environment both above‐ and belowground. Mixed models show that warming treatment dominates temperature differences belowground and at the soil surface, along with factors such as wind speed, flooding duration, and solar radiation. Aboveground warming was lower than belowground warming, but the dome design minimized issues seen in other open‐top chamber experiments. The combination of passive aboveground warming with feedback‐controlled active surface and belowground heating provides a setup for understanding warming effects on tidal ecosystems without altering the natural impacts of wind, radiation, and tidal inundations at high‐energy coastlines. Our design creates opportunities to expand future warming experiments to remote locations and technically challenging environments.

A new typology of climate change risk for European cities and regions: Principles and applications

This paper aims to contribute to the analysis of climate change risk through the development of a new spatially-explicit typology of climate risk for European cities and regions. In doing so, it offers a direct response to the Intergovernmental Panel on Climate Change (IPCC) call to advance awareness of climate change risks at sub-national levels through the integration of hazard, exposure and vulnerability domains into a composite risk classification that covers the whole of Europe. K-means clustering was applied to 49 variables at NUTS3 level where the final classification resulted in an upper-tier of eight ‘classes’, which were subsequently partitioned to derive a lower-tier of 31 ‘sub-classes’. A three-stage analysis of the eight-fold class configuration was then undertaken focusing on the distribution of climate risk classes, raising significant issues to inform climate change adaptation planning policy, practice and research. The analysis revealed an uneven distribution of climate change risk across the 33 countries covered by the typology, reinforcing the IPCC message that adapting and building resilience to climate change risk is not a ‘one-size-fits-all’ exercise. In the second stage, the analysis focused on determining whether there was a difference in the climate change risk facing different settlement types in Europe. The analysis revealed the extent of variation in the climate change risk characteristics of Europe’s urban and rural areas, revealing the potential for peri-urban areas to fall between climate change risk agendas or priorities when compared to urban–rural contexts. The final component of our analysis considered the extent to which climate change risk classes exhibit patterns of spatial clustering. Here we found that climate change risk exhibits evidence of spatial clustering but the extent of the clustering varies between different classes as the relationship between contiguous NUTS3 regions changes. This finding has notable implications for transboundary adaptation planning where discontinuities in political buy-in, competition, resourcing and awareness of risk could serve to undermine the coherence and adequacy of policy responses at a time when greater cooperation and alignment is needed.

Conscious processing of global and local auditory irregularities causes differentiated heartbeat-evoked responses.

Recent research suggests that brain-heart interactions are associated with perceptual and self-consciousness. In this line, the neural responses to visceral inputs have been hypothesized to play a leading role in shaping our subjective experience. This study aims to investigate whether the contextual processing of auditory irregularities modulates both direct neuronal responses to the auditory stimuli (ERPs) and the neural responses to heartbeats, as measured with heartbeat-evoked responses (HERs). HERs were computed in patients with disorders of consciousness, diagnosed with a minimally conscious state or unresponsive wakefulness syndrome. We tested whether HERs reflect conscious auditory perception, which can potentially provide additional information for the consciousness diagnosis. EEG recordings were taken during the local-global paradigm, which evaluates the capacity of a patient to detect the appearance of auditory irregularities at local (short-term) and global (long-term) levels. The results show that local and global effects produce distinct ERPs and HERs, which can help distinguish between the minimally conscious state and unresponsive wakefulness syndrome patients. Furthermore, we found that ERP and HER responses were not correlated suggesting that independent neuronal mechanisms are behind them. These findings suggest that HER modulations in response to auditory irregularities, especially local irregularities, may be used as a novel neural marker of consciousness and may aid in the bedside diagnosis of disorders of consciousness with a more cost-effective option than neuroimaging methods.

Numerical modelling of myocardial infarction. II. Analysis of macrophage polarization mechanism as a therapeutic target

In this study, we explore the mechanism of macrophage polarization and its significance in the development of large-scale infarction with favorable outcomes, using a minimal mathematical model of aseptic inflammation dynamics. The problem is considered in the local approximation and in the two-dimensional non-stationary formulation. The study aims to address the pertinent problem of analyzing general principles governing macrophage polarization in the context of devising therapeutic strategies and refining the "therapeutic window". Key trends are identified to enhance the effectiveness of macrophage polarization for therapeutic purposes, along with providing approximate estimations of optimal macrophage interventions that yield organ-preserving and regenerative effects. Our findings reveal that M1/M2 macrophage polarization results from an additive interplay of at least two mechanisms - cytokine-dependent activation and reprogramming of activated macrophages. Furthermore, our modeling data demonstrate the pivotal role of macrophage reprogramming as a direct response to microenvironmental changes, facilitating favorable disease progression and its outcomes. Moreover, we establish that the process of macrophage polarization plays a crucial role in localizing focal inflammation, leading to the formation of the infarction core within finite dimensions and quasi-stationary structure at the periphery, comprising immune cell clusters. The modeling results exhibit qualitative and quantitative agreement with the experimental data. Importantly, the computational experiments results align with the majority of laboratory and clinical studies, emphasizing the therapeutic potential of macrophage polarization management as a promising treatment strategy. The paper is a follow-up of the previously published work series, devoted to the study of spatial and temporal aspects of the inflammation and death processes development in heart muscle cells.

Investigating the impulse responses of renewable energy in the context of China: A Bayesian VAR Approach

This study applies a Bayesian Vector Auto Regression (VAR) technique to investigate the impulse responses (IR) of renewable energy (RE) on different macroeconomic variables, i.e., green finance (GF), investment in energy with private participation (IEPP), gross domestic product growth rate (GDPG), and foreign direct investment (FDI), in the context of China by using data from the years 2001–2020. Data normality and stationarity are validated before checking the VAR stability condition. The IR function captures the direct and reverse responses of RE with the shift of stipulated variables. Subsequently, it reveals the causal relationship between RE and the considered variables. The results are: (i) RE and GF are strongly endogenous, whereas IEPP and GDPG are weakly endogenous, and FDI is least endogenous; (ii) the response of RE is positive to GF and negative to FDI, IEPP, and GDPG. The reverse responses are quite similar except for IEPP, and (ⅲ) shocks from GF, GDPG, and FDI lead to more variability in RE than RE itself. Ultimately, it indicates RE's share in total energy output increases with the boost of GF and decreases with the amplification of FDI, IEPP, and GDPG. Inversely, RE's contribution boosts with the short-term increase in IEPP.

Effects of resilience and timing of adverse and adaptive experiences on interpersonal behavior: a transdiagnostic study in a clinical sample

Adverse childhood experiences (ACE) have been linked to less prosocial behavior during social exclusion in vulnerable groups. However, little is known about the impact of the timing of ACE and the roles of protective factors. Therefore, this study investigated the association of the behavioral response to experimental partial social exclusion with adverse and adaptive experiences across age groups and resilience in clinical groups with persistent depressive disorder and borderline personality disorder, i.e., groups with high ACE, and in healthy controls (HC) (N = 140). Adverse and adaptive experiences during childhood, youth, and adulthood were assessed with the Traumatic Antecedents Questionnaire, and resilience was measured with the Connor Davidson Resilience Scale. A modified version of the Cyberball paradigm was used to assess the direct behavioral response to partial social exclusion. In patients, adverse events during youth (B = − 0.12, p = 0.016) and adulthood (B = − 0.14, p = 0.013) were negatively associated with prosocial behavior, whereas in the HC sample, adaptive experiences during youth were positively associated with prosocial behavior (B = 0.25, p = 0.041). Resilience did not mediate these effects. The findings indicate that critical events during youth may be particularly relevant for interpersonal dysfunction in adulthood.

Pesan Anti Rasisme dalam Pertandingan Kualifikasi Euro 2020 Belanda vs Estonia di Mola TV

antagonism towards many forms of racism. Instances of racial discrimination and prejudice are prevalent within the domain of football. A diverse range of individuals, including supporters, coaches, athletes, officials overseeing matches, and media members, are accountable for participating in racist practices. The establishment of the Let's Kick Racism Out of Football program by the Federation Internationale de Football Association (FIFA) was a direct response to the occurrence of racism within the football community. The primary aim of this research is to investigate the potential existence of an anti-racist message inside the live broadcast of the Netherlands vs Estonia match on Mola TV. The research methodology adopted in this study involves using a descriptive qualitative approach. The methodology utilized in this study is the semiotic approach. The methodology adopted for data analysis is grounded in the principles of semiotics as established by Charles S. Peirce. The theoretical framework utilized in this research is the constructivism paradigm. The present study utilizes the theoretical framework of Social Reality Construction in Mass Media. The results of this study unveiled several forms of anti-racism indicators, encompassing gestures involving bodily motions, observable characteristics, spatial clues, and temporal factors. The match's goal celebration sequences effectively convey an anti-racism tone through the presence of such messages.

Reactive Cell Electrospinning of Anisotropically Aligned and Bilayer Hydrogel Nanofiber Networks.

Structured hydrogels that incorporate aligned nanofibrous morphologies have been demonstrated to better replicate the structures of native extracellular matrices and thus their function in guiding cell responses. However, current techniques for nanofiber fabrication are limited in their ability to create hydrogel scaffolds with tunable directional alignments and cell types/densities, as required to reproduce more complex native tissue structures. Herein, we leverage a reactive cell electrospinning technique based on the dynamic covalent cross-linking of poly(ethylene glycol methacrylate (POEGMA) precursor polymers to fabricate aligned hydrogel nanofibers that can be directly loaded with cells during the electrospinning process. The scaffolds were found to support high C2C12 myoblast viabilities greater than 85% over 14 days, with changes in the electrospinning collector allowing for the single-step fabrication of nonaligned, aligned, or cross-aligned nanofibrous networks. Cell aspect ratios on aligned scaffolds were found on average to be 27% higher compared to those on nonaligned scaffolds; furthermore, cell-loaded bilayer scaffolds with perpendicular fiber alignments showed evidence of enabling localized directional cell responses to individual layer fiber directions while avoiding delamination between the layers. This fabrication approach thus offers potential for better mimicking the structure and thus function of aligned and multilayered tissues (e.g., smooth muscle, neural, or tendon tissues).

O033 Is Sleeping and Waking Important for the Cortisol Awakening Response?

Abstract Introduction The rapid rise in cortisol after waking is known as the cortisol awakening response (CAR). However, as part of its normal circadian rhythm cortisol also rises in the morning independent of awakening. If CAR is a direct response to awakening, it should be eliminated in conditions of sleep deprivation (SD). Given that an atypical CAR is associated with several psychiatric and medical disorders, understanding the factors that influence CAR is of clinical relevance. This study explored cortisol during the normal waking period prior, during, and post-SD. Methods N=21 (11F 22.80±4.40y) completed 62h of SD in the laboratory. Salivary cortisol was collected across 5-time-points (07:00h, 07:15h, 07:30h, and 07:45h) on 2-pre-at-home-study days, 4-in-lab-study days, and 2-post-at-home-study days. Mixed-effects ANOVAs tested for fixed effects of day, time, and their interactions on cortisol, and cortisol area under the curve (AUCi, AUCg). Results SD produced significant effects of time*day (p<0.001). Cortisol levels at +30 and +45min post-awakening were lower on SD days. Cortisol levels on awakening (0mins) did not differ between any study days. There were significant effects of day (p<0.001). AUCi and AUCg were greater on in-laboratory-baseline and recovery days compared to other study days. Discussion This study found CAR is not present during periods of SD when there is no ‘waking’ from sleep. It showed for the first time that CAR recovers to baseline levels following recovery sleep. While the role of the CAR remains unclear this study identified factors that future research should consider to advance understanding of its purpose.

Experimental Investigation on Effects of Water Injection on Rock Frictional Sliding and Its Implications for the Mechanism of Induced Earthquake

This study conducted water-induced fault slip experiments on saw-cut granite, sandstone, and limestone samples. Experimental results demonstrated that injecting 15 MPa pressurized water into the vicinity of a high-permeability sandstone fault could decrease the effective normal stress and induce fault slip but not significantly affect the stress of granite and limestone faults due to low permeability. When the pressurized water was injected into the fault plane, 1 MPa pressurized water could not significantly affect fault stress; however, the 15 MPa pressurized water caused a significant reduction in frictional strength and induced fault sliding. The actual pore pressure differed from the injection pressure and showed significant differences in three faults, resulting in the apparent difference in stress drop, slip duration, displacement, and sliding rate. Three faults showed velocity-strengthening properties at room temperature. The fault slip caused by 15 MPa pressurized water injection was a direct response of fault strength to the reduction in effective normal stress. The limestone fault was characterized by velocity-weakening behavior at 100 °C, and the sliding rate of the fault induced by the 15 MPa pressurized water injection was faster than that at room temperature. The experiment results suggest that high-pressure injection can dominate over velocity-dependent effects, inducing fault-unstable slips in velocity-strengthening faults, but is more likely to induce medium-strong earthquakes on the velocity-weakening fault.

The Use of Modern Measuring Devices in the Evaluation of Movement in the Block in Volleyball Depending on the Difficulty of the Task Determined by Light Signals

The basic technical element that is a direct response to the opponent’s attack is the block. Blocking is related to setting the starting position of the player and choosing the most effective way to move. The aim of this study was to evaluate the time of movement in the block depending on the difficulty of the task determined by a response to light signals. The study included 14 players (17.36 ± 1.18 years). Eight discs of the FITLIGHT TrainerTM device placed at different heights near the center of the volleyball court were used for the measurements. The player’s task was to move as quickly as possible in a block after recognizing a light signal to take a specific action. Three types of tasks with different levels of difficulty were defined: reaction to the light signal on the player’s side (S1), reaction to the light signal of the upper or lower discs placed vertically over the net (S2), and reaction to the color of the light signal of the upper or lower discs placed vertically over the net (S3). The following time measurements were analyzed: indirect time (TI), time of movement to the jumping point (TJP), and total time (TT) on the right and left sides. In all measurements (TI, TJP, TT), the differences in the times obtained in tasks S1 and S2 and tasks S1 and S3 were statistically significant (p ≤ 0.001) for both the right and left sides. The comparison of the task performance times for S2 and S3 showed a difference only in the TJP measurement for the left side. An analysis of the results indicates a significant role of signal recognition and decision-making process in the player’s movement during blocking. The FITLIGHT TrainerTM device can be a useful tool for this purpose in coaching.

Mesenchymal Stem Cell-Macrophage Crosstalk Provides Specific Exosomal Cargo to Direct Immune Response Licensing of Macrophages during Inflammatory Responses.

Neurodegenerative diseases (NDDs) continue to be a significant healthcare problem. The economic and social implications of NDDs increase with longevity. NDDs are linked to neuroinflammation and activated microglia and astrocytes play a central role. There is a growing interest for stem cell-based therapy to deliver genes, and for tissue regeneration. The promise of mesenchymal stem cells (MSC) is based on their availability as off-the-shelf source, and ease of expanding from discarded tissues. We tested the hypothesis that MSC have a major role of resetting activated microglial cells. We modeledmicroglial cell lines by using U937 cell-derived M1 and M2 macrophages. We studied macrophage types, alone, or in a non-contact culture with MSCs. MSCs induced significant release of exosomes from both types of macrophages, but significantly more of theM1 type. RNAsequencing showed enhanced gene expression within the exosomes with the major changes linked to the inflammatory response, including cytokines and the purinergic receptors. Computational analyses of the transcripts supported the expected effect of MSCs in suppressing the inflammatory response of M1 macrophages. The inflammatory cargo of M1macrophage-derived exosomes revealed involvement of cytokines and purinergic receptors. At the same time, the exosomes from MSC-M2 macrophages were able to reset the classical M2 macrophages to more balanced inflammation. Interestingly, we excluded transfer of purinergic receptor transcripts from the co-cultured MSCs by analyzing these cells for the identified purinergic receptors. Since exosomes are intercellular communicators, these findings provide insights into how MSCs maymodulate tissue regeneration and neuroinflammation.

Dissociation of Centrally and Peripherally Induced Transcranial Magnetic Stimulation Effects in Nonhuman Primates.

Transcranial magnetic stimulation (TMS) is a noninvasive brain stimulation method that is rapidly growing in popularity for studying causal brain-behavior relationships. However, its dose-dependent centrally induced neural mechanisms and peripherally induced sensory costimulation effects remain debated. Understanding how TMS stimulation parameters affect brain responses is vital for the rational design of TMS protocols. Studying these mechanisms in humans is challenging because of the limited spatiotemporal resolution of available noninvasive neuroimaging methods. Here, we leverage invasive recordings of local field potentials in a male and a female nonhuman primate (rhesus macaque) to study TMS mesoscale responses. We demonstrate that early TMS-evoked potentials show a sigmoidal dose-response curve with stimulation intensity. We further show that stimulation responses are spatially specific. We use several control conditions to dissociate centrally induced neural responses from auditory and somatosensory coactivation. These results provide crucial evidence regarding TMS neural effects at the brain circuit level. Our findings are highly relevant for interpreting human TMS studies and biomarker developments for TMS target engagement in clinical applications.SIGNIFICANCE STATEMENT Transcranial magnetic stimulation (TMS) is a widely used noninvasive brain stimulation method to stimulate the human brain. To advance its utility for clinical applications, a clear understanding of its underlying physiological mechanisms is crucial. Here, we perform invasive electrophysiological recordings in the nonhuman primate brain during TMS, achieving a spatiotemporal precision not available in human EEG experiments. We find that evoked potentials are dose dependent and spatially specific, and can be separated from peripheral stimulation effects. This means that TMS-evoked responses can indicate a direct physiological stimulation response. Our work has important implications for the interpretation of human TMS-EEG recordings and biomarker development.

Hepatic arterial buffer response: activation in donor fetuses and the effect of laser ablation of intertwin anastomosis.

Hepatic arterial buffer response (HABR) is an important defence mechanism for maintaining liver blood flow. It is suspected that HABR is active in monochorionic diamniotic twins (MCDA) with twin-to-twin transfusion syndrome (TTTS) where donor compensates a setting of volume depletion and the recipient an overload. The present study investigates whether in TTTS, HABR is active in donor and/or recipient individually and try to determine if the activation of HABR is a direct response to TTTS. Hepatic artery (HA) peak systolic velocity (PSV) was measured in normal MCDA fetuses and TTTS. Correlation with relevant fetal Dopplers and characteristics were determined. Z-scores for HA-PSV (HAV-Z) were calculated and its association with TTTS in donors and recipients were determined as well as changes in HAV-Z after laser treatment. In this study 118 MCDA were included, 61.9 % normal and 38.1 % TTTS. Of the TTTS 22 required laser treatment. A total of 382 scans were performed in normal group and 155 in TTTS. Our data demonstrates that in donors HAV-Z was 2.4 Z-scores higher compared to normal fetuses (β=2.429 95 % CI 1.887, 2.971; p<0.001) and after laser treatment HAV-Z reduced (β=-1.829 95 % CI-2.593,-1.064; p<0.001). There was no significant difference between recipients and normal (β=-0.092 95 % CI-0.633, 0.449; p=0.738). HABR is active in TTTS, promoting an increased hepatic blood flow in donors. The activation is direct response to TTTS as shown by the reduction in HAV-Z after laser. This finding provides important insights into the pathophysiology of TTTS.

Three steps down: Metabolic depression in winter-acclimatized crucian carp (Carassius carassius L.)

Acclimatization of certain ectothermic vertebrates to winter conditions is associated with reduced energy consumption (winter dormancy). Principally, this may be achieved by reducing movement activity, depression of basal cellular functions, or by switching from aerobic to anaerobic energy production to sustain low energy consumption during anoxia. Therefore, we determined standard (SMR), routine (RMR) and anoxic (AMR) metabolic rates in summer- (SumA; 20 °C) and winter-acclimatized (WinA; 2 °C) crucian carp (Carassius carassius), an anoxia-tolerant teleost fish. At 20 °C, RMR was 39% lower in WinA than SumA fish (p < 0.05), indicating reduced movements in winter. SMR, measured for the first time in crucian carp, was 45% lower in WinA than SumA fish at 10 °C (p < 0.05), indicating significant reduction of energy consumption in vital cellular processes. At 2 °C, AMR - measured from ethanol production- was 78% and 97% of the SMR and RMR levels at the same temperature, respectively. The current study revealed that the winter dormancy in anoxia-tolerant crucian carp is achieved in 3 different steps: (1) by active reduction of SMR, possibly in anticipation of seasonal anoxia, (2) acute Arrhenius Q10 effect that slows SMR as well as RMR, and (3) direct response to the absence of oxygen (AMR). Furthermore, the anoxic energy production was strongly dependent on body mass with scaling exponents of −0.335 and − 0.421 for WinA and SumA fish, respectively.

Widespread synchronous decline of Mediterranean-type forest driven by accelerated aridity.

Large-scale, abrupt ecosystem change in direct response to climate extremes is a critical but poorly documented phenomenon1. Yet, recent increases in climate-induced tree mortality raise concern that some forest ecosystems are on the brink of collapse across wide environmental gradients2,3. Here we assessed climatic and productivity trends across the world's five Mediterranean forest ecosystems from 2000 to 2021 and detected a large-scale, abrupt forest browning and productivity decline in Chile (>90% of the forest in <100 days), responding to a sustained, acute drought. The extreme dry and warm conditions in Chile, unprecedented in the recent history of all Mediterranean-type ecosystems, are akin to those projected to arise in the second half of the century4. Long-term recovery of this forest is uncertain given an ongoing decline in regional water balance. This dramatic plummet of forest productivity may be a spyglass to the future for other Mediterranean ecosystems.

Wave analysis of rotors with longitudinal periodicity

The dynamics of rotating systems plays an important role in the efficiency and reliability of such machines. For this reason, understanding their dynamics is essential to predict and mitigate the resultant vibrations that can occur in such machines. Considering that vibration is essentially the propagation of waves in a continuous medium, methods of wave analysis can also be employed to investigate the dynamics of rotating systems, especially when the system presents some sort of periodicity. The difficulty lies in the fact that rotating systems are non-reciprocal systems due to the gyroscopic effects, which create forward and backward whirl motions with associated mode waves. The conventional wave methods usually do not tackle this problem. This work presents a methodology for analyzing rotating systems with wave methods based on the combination of conventional modal analysis, Bloch wave propagation theory, and directional frequency response functions. In this case, it is possible to separate the forward and backward modes, thus allowing the analysis of forward and backward wavenumbers separately. Consequently, one can draw separate dispersion diagrams for the wave modes associated with the forward and backward motions of the rotor. The numerical results show the feasibility of the method, and the methodology is applied experimentally to a rotating system in the laboratory.