Immobility Behavior Research Articles

Fabrication of a Heptapeptide-Modified Poly(glycidyl Methac-Rylate) Nanosphere for Oriented Antibody Immobilization and Immunoassay

Oriented antibody immobilization has been widely employed in immunoassays and immunodiagnoses due to its efficacy in identifying target antigens. Herein, a heptapeptide ligand, HWRGWVC (HC7), was coupled to poly(glycidyl methacrylate) (PGMA) nanospheres (PGMA-HC7). The antibody immobilization behavior and antigen recognition performance were investigated and compared with those on PGMA nanospheres by nonspecific adsorption and covalent coupling via carbodiimide chemistry. The antibodies tested included bovine, rabbit, and human immunoglobulin G (IgG), while the antigens included horseradish peroxidase (HRP) and β-2-Microglobulin (β2-MG). The nanospheres were characterized using zeta potential and particle size analyzers, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and reversed-phase chromatography, proving each synthesis step was succeeded. Isothermal titration calorimetry assay demonstrated the strong affinity interaction between IgG and PGMA-HC7. Notably, PGMA-HC7 achieved rapid and extremely high IgG adsorption capacity (~3 mg/mg) within 5 min via a specific recognition via HC7 without nonspecific interactions. Moreover, the activities of immobilized anti-HRP and anti-β2-MG antibodies obtained via affinity binding were 1.5-fold and 2-fold higher than those of their covalent coupling counterparts. Further, the oriented-immobilized anti-β2-MG antibody on PGMA-HC7 exhibited excellent performance in antigen recognition with a linear detection range of 0–5.3 μg/mL, proving its great potential in immunoassay applications.

A prefrontal-periaqueductal gray pathway differentially engages autonomic, hormonal, and behavioral features of the stress coping response.

Activation of autonomic and hypothalamo-pituitary-adrenal (HPA) systems occur interdependently with behavioral adjustments under varying environmental demands. Nevertheless, laboratory rodent studies examining the neural bases of stress responses have generally attributed increments in these systems to be monolithic, regardless of whether an active or passive coping strategy is employed. Using the shock probe defensive burying test (SPDB) to measure stress-coping features naturalistically in male and female rats, we identify a neural pathway whereby activity changes may promote distinctive response patterns of hemodynamic and HPA indices typifying active and passive coping phenotypes. Optogenetic excitation of the rostral medial prefrontal cortex (mPFC) input to the ventrolateral periaqueductal gray (vlPAG) decreased passive behavior (immobility), attenuated the glucocorticoid hormone response, but did not prevent arterial pressure and heart rate increases associated with rats' active behavioral (defensive burying) engagement during the SPDB. By contrast, inhibition of the same pathway increased behavioral immobility and attenuated hemodynamic output but did not affect glucocorticoid increases. Correlational analyses confirmed that hemodynamic increments occurred preferentially during active behaviors, and decrements during immobility epochs, whereas pathway manipulations, regardless of the directionality of effect, weakened the correlational relationship. Finally, neuroanatomical evidence indicated that the influence of the rostral mPFC-vlPAG pathway on coping response patterns are mediated predominantly through GABAergic neurons within vlPAG. These data highlight the importance of this prefrontal-midbrain connection in organizing stress-coping responses, and in coordinating bodily systems with behavioral output for adaptation to aversive experiences.Significance statement Organisms maximize fitness by exhibiting distinct stress-coping responses that are specific to a particular challenge. However, the neurobiology underlying cortical control over coping styles is poorly understood. We reveal a novel role for a prefrontal-to-ventrolateral periaqueductal gray pathway in regulating active versus passive stress-coping response patterns in rats. Optogenetic excitation of this pathway decreased behavioral passivity, attenuated stress-induced glucocorticoid increases, but did not prevent associated increases in autonomic output. Pathway inhibition increased behavioral passivity, attenuated autonomic output, but did not affect glucocorticoid increases. These data highlight the importance of this prefrontal-midbrain connection in organizing stress-coping responses, and in coordinating bodily systems with behavioral output for adaptation to aversive experiences.

High-temperature structural drivers immobilizing alkaline substances in red mud-derived mineral wool

Smelting and fiberization of red mud (RM) is an attractive approach for rapid recovery of metal resources, production of mineral wool, and immobilization of hazardous alkalis. However, an enormous challenge remains in understanding alkali immobilization behavior in mineral wool over a broad A/S (Al2O3 to SiO2 mass ratio) range. Here we addressed the challenge through molecular dynamics, thermodynamic and experimental analyses. Increasing A/S ratio caused an increasing degree of structural order and the remarkable micro-phase separation occurred at A/S > 0.9. The role of Na+ and Ca2+ changed from the network-modifying cations to the charge-compensating cations. Melt viscosity decreased and then increased significantly with an intensified temperature sensitivity, identified by the increasing viscous flow activation energy from 211.5 to 377.03 kJ/mol in the temperature region from 1500 to 1570 °C. The transformation of thermodynamic properties (real mixed/excess molar Gibbs free energies, and entropy increment) corresponded to the structural changes. Thermal, mechanical and leaching tests confirmed the negative effect of this structural transformation on alkali immobilization. The A/S ratios controlled below 0.9 were proposed for environmental benefits and product stability. The investigation of immobilization mechanism provides valuable information for tuning the vitrification chemistry and developing safe and green mineral wool from RM.

Curcumin and exercise prevent depression via alleviating hippocampus injury and improve depressive-like behaviors in chronically stressed depression rats

Background and purpose: Depression is a growing public health concern worldwide, characterized by cognitive impairment and structural abnormalities of the hippocampus. Current antidepressant treatment sometimes causes the late onset of results and the much faster occurrence of side effects. For this reason, the interest in new treatment strategies including exercise and natural products such as curcumin has increased to treat depression. The present study investigated the role of curcumin and exercise in improving depressive-like behavior and hippocampal damage induced by mild unpredictable chronic stress in male rats. Experimental approach: This study analyzed the effects of curcumin (100 mg/kg/day, P.O for 14 days) and exercise (treadmill running, 45 min/day for 14 days) on immobility behavior (forced swimming test), locomotor activity (open field test), anhedonia (sucrose preference test) and cell survival (Nissl staining) of the hippocampal CA3 region in chronically stressed depression rats. Findings/Results: In the current study, curcumin treatment combined with exercise effectively improved immobility behavior, locomotor activity, and increased hippocampal cell survival resulted in preventing the development of hippocampus dysfunction and depressive-like behaviors. Conclusion and implications: This study demonstrated a new prospect for treating depression. The current findings give researchers the confidence to continue the investigations on the effects of curcumin accompanied with exercise as a novel therapy for the treatment of depression.

Immobilization of heavy metals with chlorine and liquid phase formation during thermal treatment of MSWI fly ash

Due to effective detoxification, thermal treatment is a preferred treatment technology of municipal solid waste incineration (MSWI) fly ash. However, immobilization behavior of heavy metals during thermal treatment is unclear. In this work, a circulated fluidized bed fly ash with SiO2 addition and a grate furnace fly ash with high silica-aluminum coal ash addition were used to investigate combined effect of active chlorine content, liquid polymerization degree, temperature of initial liquid phase formation and liquid phase formation rate on the immobilization ratios of Zn, Pb and Cd by principle component analysis (PCA). The results show that the decrease in active chlorine content favors the immobilization of Zn, Pb and Cd because chlorination volatilization is reduced. Both the increase in liquid polymerization degree and the formation of initial liquid phase at low temperature promote the immobilization of Zn, Pb and Cd for physical encapsulation. However, a rapid formation of liquid phase is not favorable for the immobilization of Zn, Pb and Cd, because transfer of heavy metals between crystals and liquid phase is impeded by high viscosity of liquid phase during fusion. The results can provide a reference for how to achieve the immobilization of heavy metals by adjusting the chemical composition of MSWI fly ash during thermal treatment.

Differential efficacy of modified enriched environment on motor, emotion, and cognition in cortical ischemic mice.

A modified enriched environment (mEE) with 12 h per night was recently proposed and exhibited cognitive improvement. The present study aimed to evaluate the effects of different courses of mEE on different deficits in ischemic mice. Mice were subjected to photothrombotic stroke at the left sensorimotor cortex and then randomly assigned to standard environment or mEE for 7 d (St-PE) or 28d (Ct-PE) on the third day post-stroke. Neurological deficits and sensorimotor, emotional, and cognitive performances were assessed at the 10th, 17th, and 31st days post-stroke. Our results demonstrated that Ct-PE ameliorated neurological deficits, forelimb using asymmetry, and reduced slip rates of the affected limbs at all time points, while this effect of St-PE was observed only on the 10th day. Similarly, Ct-PE for 28d promoted spatial learning and working memory, but St-PE did not. Differently, ischemic mice in both St-PE and Ct-PE groups exhibited increased exploration behavior in the open field, light-dark box and elevated plus maze, and less immobile behavior during the tail suspension at all the time points. Our findings indicated that Ct-PE improved sensorimotor and cognitive dysfunctions after cortical ischemia in a time-dependent manner, but St-PE appeared to have greater therapeutic potential on anxiety and depression.

Mechanisms involved in the antidepressant-like action of orally administered 5-((4-methoxyphenyl)thio)benzo[c][1,2,5]thiadiazole (MTDZ) in male and female mice.

The compound 5-((4-methoxyphenyl)thio)benzo[c][1,2,5]thiadiazole (MTDZ) has recently been shown to inhibit in vitro acetylcholinesterase activity, reduce cognitive damage, and improve neuropsychic behavior in mice, making it a promising molecule to treat depression. This study investigated the antidepressant-like action of MTDZ in mice and its potential mechanisms of action. Molecular docking assays were performed and suggested a potential inhibition of monoamine oxidase A (MAO-A) by MTDZ. The toxicity study revealed that MTDZ displayed no signs of toxicity, changes in oxidative parameters, or alterations to biochemistry markers, even at a high dose of 300 mg/kg. In behavioral tests, MTDZ administration reduced immobility behavior during the forced swim test (FST) without adjusting the climbing parameter, suggesting it has an antidepressant effect. The antidepressant-like action of MTDZ was negated with the administration of 5-HT1A, 5-HT1A/1B, and 5-HT3 receptor antagonists, implying the involvement of serotonergic pathways. Moreover, the antidepressant-like action of MTDZ was linked to the NO system, as L-arginine pretreatment inhibited its activity. The ex vivo assays indicated that MTDZ normalized ATPase activity, potentially linking this behavior to its antidepressant-like action. MTDZ treatment restricted MAO-A activity in the cerebral cortices and hippocampi of mice, proposing a selective inhibition of MAO-A associated with the antidepressant-like effect of the compound. These findings suggest that MTDZ may serve as a promising antidepressant agent due to its selective inhibition of MAO-A and the involvement of serotonergic and NO pathways.

SERT and OCT mediate 5-HT1B receptor regulation of immobility behavior and uptake of 5-HT and HIS

5-HT clearance, commonly mediated by transporters in the uptake-1 and uptake-2 families, has been linked to 5-HT1B receptor’s action on behaviors. Since no specific transporters identified yet, effects of serotonin transporter (SERT) and organic cation transporter (OCTs) on 5-HT1B-elicited immobility phenotype, and 5-HT and HIS uptake were then investigated. Intraperitoneal injections of SERT inhibitor fluoxetine (FLX) and/or OCTs inhibitor decynium (D22) were used prior to local perfusion of 5-HT1B agonist CP93129 into the ventral hippocampus to measure immobility times in the FST and TST, to measure 5-HT uptake efficiencies and HIS uptake efficiencies derived from linear regressions using the transient no-net-flux quantitative microdialysis in C57BL/6 mice. Exogenous 5-HT and HIS uptake were measured following incubation of FLX and/or D22 with CP93129 in the RBL-2H3 cells. Moreover, surface membrane levels of SERT and OCT were detected in response to CP93129. Local CP93129 prolonged immobility times, which were attenuated following pretreatment of either inhibitor. Local CP93129 lowered the slopes obtained from the lineal regressions for 5-HT and HIS (slope is reciprocal to uptake efficiency), which were then weakened following pretreatment of either inhibitor. Similar findings were obtained following CP93129 incubation, and co-incubation of CP93129 with either inhibitor in the RBL-2H3. Moreover, CP93129 dose-dependently moved SERT and OCT3 in the cytosol to the surface membrane. Both SERT and OCT are the target effectors mediating 5-HT1B regulation of immobility time and 5-HT uptake, OCT mediates 5-HT1B regulation of HIS uptake. Their underlying signal transductions need to be further explored.

Formation processes of iron-based layered hydroxide in acid mine drainage and its implications for in-situ arsenate immobilization: Insights and mechanisms

The immobilization of arsenate in transformed minerals depends on their states in acid mine drainage (AMD). In this study, an iron-based layer hydroxide mineral was derived from the transformation of ferrihydrite under co-existing Mg2+ ions in AMD. The immobilization behavior of arsenate on the mineralized LDHm and pre-prepared LDHad was distinguished. 99 % immobilization efficiency was achieved from the mineralized LDHm, maintaining stability without subsequent releases, across initial arsenate concentrations ranging from 10 to 60 mg/L. LDHm outperformed the pre-prepared LDHad, which was synthesized from AMD for arsenate adsorption. Electron energy loss spectroscopy line profiles revealed predominant incorporation of arsenate in the LDHm structure, supported by higher bulk As signals within LDHm. Density functional theory calculations indicated primary arsenate incorporation into LDHm, forming stable bonds with lower energy activation barriers. Importantly, LDHm exhibited a superior electron rearrangement configuration, resulting in enhanced electron state activity and affinity for arsenate. In contrast, arsenate adsorption predominantly occurred on the pre-prepared LDHad, with notable As signals detected particularly at the edges. Adsorption energy evaluation indicated arsenate preference for bonding to Fe3+ sites on LDHad. These findings provide important insights into the role of stable LDH-like minerals for long-term arsenate immobilization in the natural AMD attenuation processes.

Immobilization Behavior and Mechanism of Cd2+ by Sulfate-Reducing Bacteria in Anoxic Environments

It is vital to remove cadmium from wastewater because of its potential harm to the natural environment and human health. It was found that sulfate-reducing bacteria (SRB) had a good fixing effect on Cd under a strict anaerobic environment. However, there are few reports on the immobilization effect and mechanism of SRB on Cd in an anoxic environment. This study revealed the effects of initial Cd2+ concentration, initial SO42− concentration, temperature, pH, and C/N ratio on the immobilization of Cd2+ by SRB in aqueous solution under an anoxic environment. The experimental results showed that under the conditions of initial concentration of Cd2+ within 0 mg/L~30 mg/L, initial concentration of SO42− within 1200 mg/L, temperature within 25 °C~35 °C, pH neutral, and C/N ratio of 20:1, the immobilization rate of Cd2+ by SRB is above 90%. The characterization results showed that bioadsorption and chemical precipitation were the main mechanisms of SRB immobilization of Cd2+ in an anoxic environment.

All-optical presynaptic plasticity induction by photoactivated adenylyl cyclase targeted to axon terminals

Intracellular signaling plays essential roles in various cell types. In the central nervous system, signaling cascades are strictly regulated in a spatiotemporally specific manner to govern brain function; for example, presynaptic cyclic adenosine monophosphate (cAMP) can enhance the probability of neurotransmitter release. In the last decade, channelrhodopsin-2 has been engineered for subcellular targeting using localization tags, but optogenetic tools for intracellular signaling are not well developed. Therefore, we engineered a selective presynaptic fusion tag for photoactivated adenylyl cyclase (bPAC-Syn1a) and found its high localization at presynaptic terminals. Furthermore, an all-optical electrophysiological method revealed rapid and robust short-term potentiation by bPAC-Syn1a at brain stem-amygdala synapses in acute brain slices. Additionally, bPAC-Syn1a modulated mouse immobility behavior. These results indicate that bPAC-Syn1a can manipulate presynaptic cAMP signaling invitro and invivo. The all-optical manipulation technique developed in this study can help further elucidate the dynamic regulation of various cellular functions.

Decreased hippocampal microglial cell activation by methanolic extract from the leaves of Mallotus oppositifolius (Geiseler) Müll. Arg contributes to its antidepressant-like effect

Background Natural remedies with neuroprotective effect are useful in neuroinflammation-associated depression. Although Mallotus oppositifolius extract (MOE) has previously demonstrated antidepressant and anti-inflammatory properties, its neuroprotective effect remains unknown. Thus, the study evaluated the effect of MOE on lipopolysaccharide (LPS)-induced neuroinflammation-associated depression in mice. Methods Antidepressant-like effect of MOE (10 – 100 mg/kg), fluoxetine (20 mg/kg) and minocycline (50 mg/kg) was established in naïve Institute of Cancer Research (ICR) mice using the forced swim (FST), tail suspension (TST) and open-space swim (OSST) tests. In a separate experiment, FST and TST were used to assess the effect of an 11-day pre-treatment with MOE (10 – 100 mg/kg) or minocycline (50 mg/kg) on LPS (1 mg/kg) neuroinflammation at 6 and 24 hours post LPS. Following these tests, mice were sacrificed and their hippocampi isolated to evaluate their resting and activated microglial cells using Golgi-Cox staining technique. Open-field test was used to assess locomotor activity. Results MOE, fluoxetine and minocycline significantly reduced immobility in FST, TST and OSST compared to vehicle (p < 0.05), confirming their antidepressant-like effect. Interestingly, MOE’s antidepressant-like effect was faster than fluoxetine and minocycline. Conversely, LPS treatment increased immobility behavior at 6 and 24 hours, suggestive of neuroinflammation-induced depression. Compared to vehicle group, pre-treatment with MOE and minocycline ameliorated LPS-induced hippocampal microglial activation and reversed increased immobility behavior without affecting locomotor activity (p < 0.05). Resting microglial cell count was significantly increased by MOE pre-treatment in the OSST-challenged mice compared to vehicle group (p < 0.01). Similarly, MOE pre-treatment reversed LPS-induced reduction in resting microglial count, and restored resting microglial count to normal levels compared to LPS naive vehicle group. Conclusions Collectively, the results suggest that MOE exerts neuroprotective effect against LPS-induced neuroinflammation by decreasing the activation of microglia and increasing resting microglial count. This contributes to its antidepressant-like effect.

Comparison of water-soluble organic matter (WSOM)-containing and WSOM-free biochars for simultaneous sorption of lead and cadmium

The effects of individual biochar constituents and natural environmental media on the immobilization behaviors and chemical activities of toxic heavy metals are still poorly understood. In this work, the physicochemical properties of raw corn straw (CS) and CS-derived biochar materials as well as their sorption abilities and retention mechanisms for lead (Pb) and cadmium (Cd) were evaluated by combining batch experiments and spectral approaches. According to the spectral analysis results and single variable principle, the setting of biochars after soaking in solution as the control group was suggested when evaluating their retention mechanisms for Pb and Cd. The rising of ionic strength did not apparently affect the immobilization of Pb by biochar prepared at 500 °C (i.e., CB500) and Pb/Cd by water-soluble organic matter (WSOM)-free CB500 (i.e., DCB500), while slightly inhibited the sorption of Cd by CB500. Pb and Cd exhibited a mutual inhibition effect on their sorption trends with a higher sorption preference of Pb. The dominant fixation mechanism of Pb by CB500 and DCB500 was identified to be mineral precipitation. In contrast, the main sorption mechanism of Cd changed from mineral precipitation in the single-metal system to surface complexation in the binary-metal system. The sorption ratios of Pb and Cd on CB500 were comparable to those on DCB500 with the coexistence of mixed natural organic matters (NOM) and ferrihydrite. The current experimental findings suggested that DCB500 was a suitable remediation agent for regulating the migration behaviors of toxic Pb and Cd in acidic and NOM-rich soil and water systems.

Detection of Microorganisms Using Artificial Siderophore-FeIII Complex-Modified Substrates.

Four FeIII complexes of typical artificial siderophore ligands containing catecholate and/or hydroxamate groups of tricatecholate, biscatecholate-monohydroxamate, monocatecholate-bishydroxamate, and trihydroxamate type artificial siderophores (K3[FeIIILC3], K2[FeIIILC2H1], K[FeIIILC1H2], and [FeIIILH3]) were modified on Au substrate surfaces. Their abilities to adsorb microorganisms were investigated using scanning electron microscopy, quartz crystal microbalance, and AC impedance methods. The artificial siderophore-iron complexes modified on Au substrates (FeLC3/Au, FeLC2H1/Au, FeLC1H2/Au, and FeLH3/Au) showed the selective immobilization behavior for various microorganisms, depending on the structural features of the artificial siderophores (the number of catecholate and hydroxamate arms). Their specificities corresponded well with the structural characteristics of natural siderophores released by microorganisms and used for FeIII ion uptake. These findings suggest that they were generated via specific interactions between the artificial siderophore-FeIII complexes and the receptors on microorganism surfaces. Our observations revealed that the FeL/Au systems may be potentially used as effective microbe-capturing probes that can enable rapid and simple detection and identification of various microorganisms.

Predator Odor Stressor, 2,3,5-Trimethyl-3-Thiazoline (TMT): Assessment of Stress Reactive Behaviors During an Animal Model of Traumatic Stress in Rats.

Animal models utilizing predator odor stress are important in understanding implications for post-traumatic stress disorder. 2,5-dihydro-2,4,5-trimethylthiazoline (TMT) has been used to measure stress reactive behaviors during TMT exposure, indicative of stress coping behaviors. In addition, long-term consequences of stress including contextual-induced stress memory, anxiety-like and hyperarousal behaviors, and subsequent increases in alcohol self-administration can also be examined after TMT exposure. In this article, we describe the TMT exposure protocol used in our lab and how we measure different stress-reactive behaviors that rats engage in during the TMT exposure. Rats are placed in Plexiglass chambers that contain white bedding on the bottom of the chamber and a metal basket in the top right corner containing a filter paper that 10 µl of TMT is pipetted onto. During the 10 min exposure, rats can move around the chamber freely. Exposures are recorded by a video camera for later analysis. During TMT exposure, rats engage in a variety of stress-reactive behaviors, including digging and immobility behavior. These are two distinctly different types of stress-induced behavioral coping strategies to measure individual differences in stress responsivity. To examine individual differences, we group rats into TMT-subgroups based on time spent engaging in digging or immobility behavior. We calculate a digging/immobility ratio score in which we divide the total time spent digging by the total time spent immobile. A cut-off strategy is used such that rats with a criterion ratio score <1.0 are classified as TMT-1 (i.e., low digging/high immobility; greater passive coping) and rats with a ratio score >1.0 are classified as TMT-2 (i.e., high digging/low immobility; greater active coping). Here, we provide a detailed description of the TMT exposure protocol and step-by-step process in evaluation of stress-reactive behaviors. © 2024 Wiley Periodicals LLC. Basic Protocol 1: Predator odor stressor exposure using TMT Basic Protocol 2: Description of stress-reactive behaviors during TMT exposure and formation of TMT-subgroups.

Microorganism Immobilization Device Using Artificial Siderophores

Inspired by the mechanism by which microorganisms utilize siderophores to ingest iron, four different FeIII complexes of typical artificial siderophore ligands containing catecholate and/or hydroxamate groups, K3[FeIII-LC3], K2[FeIII-LC2H1], K[FeIII-LC1H2], and [FeIII-LH3], were prepared. They were modified on an Au substrate surface (Fe-L/Au) and applied as microorganism immobilization devices for fast, sensitive, selective detection of microorganisms, where H6LC3, H5LC2H1, H4LC1H2, and H3LH3 denote the tri-catecholate, biscatecholate-monohydroxamate, monocatecholate-bishydroxamate, and tri-hydroxamate type of artificial siderophores, respectively. Their adsorption properties for the several microorganisms were investigated using scanning electron microscopy (SEM), quartz crystal microbalance (QCM), and electric impedance spectroscopy (EIS) methods. The artificial siderophore-iron complexes modified on the Au substrates Fe-LC3/Au, Fe-LC2H1/Au, Fe-LC1H2/Au, and Fe-LH3/Au showed specific microorganism immobilization behavior with selectivity based on the structure of the artificial siderophores. Their specificities corresponded well with the structural characteristics of natural siderophores that microorganisms release from the cell and/or use to take up an iron. These findings suggest that release and uptake are achieved through specific interactions between the artificial siderophore-FeIII complexes and receptors on the cell surfaces of microorganisms. This study revealed that Fe-L/Au systems have specific potential to serve as effective immobilization probes of microorganisms for rapid, selective detection and identification of a variety of microorganisms.

Geographical immobility and local ancestral ties: a study of three generations of natives in Finland

ABSTRACT Research concerning internal migration has increasingly recognized family members outside the household as important factors for mobility decisions. Older generations and familiar environments constitute strong attractors thanks to location-specific capital and exchange of multigenerational support. Less is known about geographical immobility across generations. Wee study immobility patterns across three generations of native Finns by examining population register data that span over five decades. We analyse how geographical immobility in terms of a person’s place of residence at age 35 vs age 14 relates to the place of birth of their parents and grandparents. In this regard, Finland offers a highly useful case study because of its two main ethnolinguistic groups, Finnish and Swedish speakers, which are characterized by historically different mobility patterns and geographical concentrations. We find that geographical immobility relates strongly to local ancestral ties, that geographical immobility is much more common among Swedish than Finnish speakers, that the association between local ancestral ties and geographical immobility is stronger for Swedish than for Finnish speakers, and that it differs across geographical areas with different ethnolinguistic profiles. In terms of effect sizes, local ancestral ties have a large role in immobility behaviour, equally important as many socioeconomic and demographic factors.

Highly pathogenic avian influenza affects vultures’ movements and breeding output

An exceptional highly pathogenic avian influenza (HPAI) outbreak due to H5N1 virus genotypes belonging to clade 2.3.4.4.b has been affecting birds worldwide since autumn 2021.1,2,3 Mortality caused by viral infection has been well documented in poultry and more recently in wild birds, especially in seabird-breeding colonies.4,5,6 However, there is a critical lack of knowledge about how terrestrial birds deal with HPAI virus infections in terms of behavior and space use, especially during the breeding season.7,8,9 Understanding how birds move when they are infected could help evaluate the risk of spreading the virus at a distance among other populations of wild or domestic birds, this latter risk being especially important for commensal bird species. Through long-term GPS tracking, we described the changes in daily movement patterns of 31 adult griffon vultures Gyps fulvus in two French sites in 2022 compared with 3 previous years. In spring 2022, 21 vultures at both sites showed periods of immobility at the nest, during 5.6days on average. Positive serological status of 2 individuals confirmed that they had been infected by HPAI viruses. Death was recorded for 3 of the 31 tracked individuals, whereas all others recovered and returned quickly to their foraging routine, although at least 9 birds failed breeding. Such immobility patterns and death rates were never observed in previous years and were not related to weather conditions. The high immobility behavior of infected birds could reduce the risks of transmission. The observed vulnerability to HPAI viruses questions the resistance of endangered vulture species worldwide if infected.

Impact of environmental enrichment on the GABAergic neurons and glucocorticoid receptors in the hippocampus and nucleus accumbens of Wistar rats: Pro-resilient effects

The unpredictable chronic mild stress (UCMS) model has been used to induce depressive-like symptoms in animal models. Our work aims to evaluate the impact of environmental enrichment on male Wistar rats in an animal model for depression. For this purpose, we aim to assess changes in GR and GABAergic (PV+) density in cerebral regions related to cognitive-affective processes associated with depressive disorder, such as the dorsal- ventral hippocampus and accumbens nuclei.Three groups of rats were used: UCMs (unpredictable chronic mild stress), EE+ UCMs (enrichment + stress) and CONT (behavioral tests only). Hedonic responses elicited by sucrose solution were examined by licking behavior analysis; the anxiety level was evaluated using the elevated zero maze and the forced swimming (passive coping) tests. The environmental enrichment reduced the effects of chronic stress, promoting greater resilience. Thus, the UCMs group showed an anhedonia response, more anxiety and immobility behavior than either the control or the EE+ UCMs groups. Regarding immunochemistry results, there was a reduction in GABAergic activity coupled with increased activation of GR in UCMs in the dorsal hippocampus, but there were no differences between groups in the ventral hippocampus.These results suggest environmental enrichment could enhance greater resilience, reducing the vulnerability of the subjects to develop disorders such as depression and anxiety.

Fungal-assisted immobilization of microalgae for simultaneous harvesting and product customization: Effects of geometry, loading, and microalgae concentration

The production of sustainable foods and other bioproducts is expected to increase to achieve key circular bioeconomy goals. In this study, Haematococcus pluvialis microalgae cells were simultaneously harvested and immobilized in the hyphal matrix of the edible fungal strain Aspergillus awamori. The study investigated the impact of fungal loading, pellet geometry, and initial microalgae cell concentration on the immobilization performance and product characteristics. It was found that higher fungal loading and larger fungal pellets contributed to increased immobilization performance. High initial microalgae concentrations led to substantial inhibition of the immobilization behavior, which could be partially overcome by increased specific loading rate of fungi (g/g algae). A proof-of-concept demonstration study of product protein content showed that manipulation of key operational parameters allowed the product composition to be tuned to desired criteria. This study provides new insights to the fungal-assisted microalgae immobilization process and demonstrates a novel application in bioproduct customization.