Recovery Dynamics Research Articles

Dynamic response of red blood cells in health and disease.

The viscoelastic response of the red blood cells (RBCs) affected by hematological disorders become severely impaired by the altered biophysical and morphological properties. These include traits like reduced deformability, increased membrane viscosity, and change in cell shape, causing substantial changes in the overall hemodynamics. RBCs, by virtue of their highly elastic membrane and low bending rigidity, exhibit complex dynamics when exposed to cyclic, transient forces in the microcirculation. Here, we employ mesoscopic numerical simulations based on the dissipative particle dynamics (DPD) framework to explore the dynamics of healthy, schizont stage malaria-infected and type 2 diabetes mellitus affected RBCs subjected to external time-dependent loads. The paper focuses on the imposition and cessation of external forcing on the cells of two different typologies, saw-tooth cyclic wave loading and sudden loads in the form of creep and relaxation phenomena. The effects of varying the rate of stress and the applied stress magnitude were investigated. Our simulations disclosed unique shape transitions of the hysteresis curves at varied loading rates. A careful analysis reveals a critical threshold of half cycle time of the from wherein the deformation of all cells observed, healthy or otherwise, falls under the nearly reversible deformation regime displaying minimal energy dissipation. Finally, we also examined the individual effects of the different constitutive and geometric characteristics attributed to the pathological cells and observed interesting recovery dynamics of spherocytes and cells having high shear moduli. The distinguished deformation behaviour of healthy and diseased cells could establish external force as a valuable initial biomarker.

Tree sapling vitality and recovery following the unprecedented 2018 drought in central Europe

BackgroundOngoing climate change is anticipated to increase the frequency and intensity of drought events, thereby affecting forest recovery dynamics and elevating tree mortality. The drought of 2018, with its exceptional intensity and duration, had a significant adverse impact on tree species throughout Central Europe. However, our understanding of the resistance to and recovery of young trees from drought stress remains limited. Here, we examined the recovery patterns of native deciduous tree sapling species following the 2018 drought, and explored the impact of soil depth, understory vegetation, and litter cover on this recovery. MethodsA total of 1,149 saplings of seven deciduous tree species were monitored in the understory of old-growth forests in Northern Bavaria, Central Germany. The vitality of the saplings was recorded from 2018 to 2021 on 170 plots. ResultsFagus sylvatica was the most drought-resistant species, followed by Betula pendula, Acer pseudoplatanus, Quercus spp., Corylus avellana, Carpinus betulus, and Sorbus aucuparia. Although the drought conditions persisted one year later, all species recovered significantly from the 2018 drought, albeit with a slight decrease in vitality by 2021. In 2018, the drought exhibited a more pronounced adverse effect on saplings in deciduous forests compared to mixed and coniferous forests. Conversely, sapling recovery in coniferous and mixed forests exceeded that observed in deciduous forests in 2019. The pivotal factors influencing sapling resilience to drought were forest types, soil depth, and understory vegetation, whereas litter and forest canopy cover had a negative impact. ConclusionLong-term responses of tree species to drought can be best discerned through continuous health monitoring. These findings demonstrate the natural regeneration potential of deciduous species in the context of climate change. Selective tree species planting, soil management practices, and promoting understory diversity should be considered when implementing adaptive management strategies to enhance forest resilience to drought events.

Contextualizing patterns in short-term disaster recoveries from the 2015 Nepal earthquakes: household vulnerabilities, adaptive capacities, and change

Disaster recovery is multidimensional and requires theoretical and methodological approaches from the interdisciplinary social sciences to illustrate short- and long-term recovery dynamics that can guide more informed and equitable policy and interventions. The 2015 Nepal earthquakes have had catastrophic impacts on historically marginalized ethnic groups and Indigenous households in rural locations, arising in the immediate aftermath and unfolding for years afterward. Analyzing factors that shape household recovery patterns can help identify vulnerabilities and adaptive capacities in addition to signaling potential future changes. We pursue this goal using survey data from 400 randomly selected households in 4 communities over 2 10-week intervals at 9 months and 1.5 years after the earthquakes. Building on previous research that used non-metric multidimensional scaling ordination to identify patterns among multiple indicators of recovery (Spoon et al. 2020a), we investigate associations among these patterns of recovery, hazard exposure, and four domains of household adaptive capacity: institutional participation, livelihood diversity, connectivity, and social memory. Our results suggest: (1) social inequality, high hazard exposure, and disrupted place-based livelihoods (especially for herders, farmers, and forest harvesters on the geographic margins) had strong associations with negative recovery outcomes and displacement; (2) inaccessibility and marginality appeared to stimulate ingenuity despite challenging circumstances through mutual aid and local knowledge; (3) recoveries were non-linear, differing for households displaced from their primary home and agropastoral practice and those displaced to camps; and (4) some households experienced rapid changes while others stagnated. We contribute a temporal dataset with a random sample collected following a disaster that uses a theoretically informed quantitative methodology to explore linear and non-linear relationships among multidimensional recovery, adaptive capacity and change and provide an example of how vulnerabilities interact with adaptive capacity.

Facial palsy in a newborn: A case report

Unilateral congenital facial palsy in the newborn occurs more often as isolated than in the context of syndromes or developmental defects. Recognition of the etiological factor, the severity of the clinical presentation, the dynamics of recovery are a guide for a multidisciplinary approach, a range of investigations and treatment. In a non-therapeutic approach, unsupported by sufficiently reliable data from the literature, there is a dilemma whether and how long one has to wait and observe the improvement of clinical results, before determining the range of examinations in the newborn. In facial paresis of prenatal or perinatal origin, identical to non-congenital Bell's palsy, infectious and anatomical-structural causes should initially be excluded. This paper presents a case of a symmetrical hypotrophic premature infant with a manifestation of acute Bell's palsy at birth, with negative biomarkers for infectious etiology and a normal brain ultrasound. The newborn underwent a special neonatal care with targeted local treatment. Towards the end of the first postnatal week, there was an evident withdrawal of clinical symptomatology.

Influence of vesicourethral segment reconstruction techniques in radical prostatectomy on urinary continence: evaluation of immediate and long-term outcomes

Introduction. Currently, various methods and modifications of radical prostatectomy (RP) have been developed and tested, aimed at preventing and minimizing the development of urinary incontinence (UI). However, UI remains an urgent problem in patients who undergo RP, especially at the early follow-up stages.Objective. To evaluate and compare the effectiveness of modified reconstructive techniques for vesicourethral anastomosis in radical prostatectomy for the prevention of urinary incontinence with respect to the standard technique at different follow-up periods.Materials and methods. Design: single-centre, clinical, simple, comparative, parallel-group study with retrospective and prospective material evaluation, conducted in 2017 – 2022. Patients: men with verified prostate cancer cT1a – 2cN0 – xM0 without decompensated comorbidities. Age: 45 – 78 years. Retrospective part — group (G) 1: 90 patients who underwent non-nerve-sparing open retropubic RP with a "classic" vesicourethral anastomosis (VUA). Prospective part — G2: 46 patients who underwent similar surgery with modified VUA in two variations: without and with prostatic urethra-sparing — G2a (n = 25) and G2b (n = 21), respectively. Initial examination: standard preoperative laboratory and instrumental examination, assessment of lower urinary tract symptoms (LUTS) using the IPSS-QoL questionnaire. Follow-up examination: objective evaluation of UI according to established criteria and subjective assessment using the ICIQ-SF questionnaire, tracking the dynamics of LUTS using IPSS-QoL. Follow-up periods: 0-point (after catheter removal), 1, 3, 6, and 12 months (exit-point); the dynamics of recovery of urinary continence (UC) was determined monthly. Statistical analysis: Statistica ver.10.0 (StatSoft Inc., Tulsa, OK, USA) using non-parametric methods (CL p < 0.05 at a = 0.05)Results. Preoperative demographic, questionnaire and instrumental statistics did not differ (p > 0.05) between the groups, confirming the homogeneity of the samples. After RP, the urethral catheter was removed in a period of 7 to 21 days. There was no difference (p > 0.05) in the duration of drainage between the groups. Total urinary continence (TUC) immediately after catheter removal was detected in G1, G2a and G2b in 20.0%, 44.0% and 57.1% of cases, respectively. Subsequent objective monitoring of UC recovery from 1 month showed differences (p < 0.001) between the groups in the dynamics of rehabilitation during the year. The improvement in UC over the one-year follow-up period was cumulatively achieved in G1, G2a and G2b in 48.9%, 44.0% and 33.3% of cases, respectively. Total UI persisted in G1 and G2a by month 12 in 22.2% and 8.0% of patients, respectively, and was not detected in G2b. The severity of UI by the end of the follow-up according to the ICIQ-SF data was the most pronounced (p < 0.001) in patients from G1. TUC-patients in all groups from 1 month showed a marked decrease in the severity of obstructive and irritative LUTS and improved quality of life, with no differences (0.157 < p < 0.390) in IPSS-QoL values between groups.Conclusions. The use of modified VUA reconstruction techniques made it possible, compared with the standard one, to achieve high continence rates in patients both immediately after the removal of the urethral catheter and at subsequent follow-up periods, without the formation of severe iatrogenic obstruction. Prostatic urethra-sparing modification is the most effective technique that provided the rehabilitation of UI to a complete and/or social level in all patients within a year after surgery.

Remote evaluation of the recovery of vegetation affected by forest fires

Forest fires alter ecosystem processes and interactions. However, not all fires are the same, some are more severe than others,their impact on the vegetation varying according to the degree of severity. Therefore, it is important to have information thatallows sizing these impacts and supports the implementation of management strategies. However, monitoring the impact of fireis not an easy task, much less monitoring the response of the ecosystem over the years. Accordingly, the objective of this workwas to implement satellite technology to monitor the dynamics of forest cover recovery in areas impacted by forest fires, inorder to direct ecosystem restoration strategies. For this, the difference (before and after the fire) of the normalized burningratio (dNBR) was defined to determine the severity of a fire that occurred in the Sian Ka'an Biosphere Reserve in 2019.Subsequently, the dynamic of ecosystem recovery was evaluated, through the analysis of a series of images, using thefollowing indexes: a) Normalized Difference Vegetation Index (NDVI); b) Normalized burn ratio (NBR); c) NormalizedThermal Burnup Ratio (NBRT); d) Burned Area Index (BAI). A change in the reflectance value was observed in the burnedarea after the fire, which was restored over time. However, although the values show a recovery of the vegetation, in the fieldthe ecosystem is made up of different species from those that were present before the fire, therefore, by means of the spectralsignature of the vegetation, an image was generated showing the difference in the density of vegetation, which favors theunderstanding of the effects of fire and helps define priority areas to direct restoration actions.

2158. Monitoring of Varicella specific T-cell mediated immunity in pediatric allogenic hematopoietic stem cell transplant recipients

Abstract Background Varicella-zoster virus (VZV) infection is known to occur in 13-55% of patients within the first year after hematopoietic stem cell transplant (HSCT). The dynamics of recovery of VZV-specific T cell- mediated immunity (CMI) and its role for prevention and control of VZV reactivation are rarely reported in pediatric allogenic HSCT recipients. Methods From April 2019 to February 2020, subjects aged younger than 19 years who underwent allogenic HSCT with at least 1 year of follow up at Asan Medical Center Children`s Hospital were prospectively enrolled. All of them underwent VZV-specific enzyme-linked immune absorbent spot (ELISPOT) assays just before HSCT and then at 1, 3 months following HSCT. Extension study, which measures VZV-specific CMI before and after VZV vaccination at 24 months post-HSCT, is currently underway. Results A total of 32 HSCT recipients with a median age of 11years were enrolled. 37.5% underwent haploidentical HSCT and VZV R+ were in 78.1%. Antiviral prophylaxis was applied to all HSCT recipients, of which 65.6% were applied up to 365 days after HSCT. During this study period, only 1 patient (3.1%) experienced herpes zoster at 23 months following HSCT, whose VZV-specific ELISPOT assay showed 0, 1, and 0 spot-forming cells (SFC)/2.0x105 cells before HSCT, 1 and 3 months following HSCT, respectively. The presence of VZV-specific CMI ≥ 1 SFC/ 2.0 × 105 cells was observed in 62.5 % before HSCT, 65.6 % at 1 month, 59.4 % at 3 months, and 70% at 24 months after HSCT, respectively. However, only 18.8 % ,12.5 % and 21.9 % recovered VZV-specific CMI with ≥ 5 SFC/ 2.0 × 105 cells at 1, 3 and 24 months following HSCT. Meanwhile, all the 4 recipients who got the 1st VZV vaccination at 24 months following HSCT showed recovery of VZV-specific CMI with ≥ 5 SFC/ 2.0 × 105 cell. Recovery of VZV-specific CMI after HSCT was not associated with VZV serostatus, chickenpox history, type of HSCT, conditioning regimens, and GVHD. Conclusion Only a few pediatric allogenic HSCT recipients recovered VZV-specific CMI with ≥ 5 SFC/ 2.0 × 105 cell up to 2 years following HSCT. In addition, the association between VZV-specific CMI and VZV reactivation could not be analyzed because no one experienced VZV reactivation within 1 year after HSCT. More long-term large-scale multicenter study is mandatory to supplement these parts. Disclosures All Authors: No reported disclosures.

One experiment makes a direct comparison of structural recovery with equilibrium relaxation.

For a molecular glass-former, propylene glycol, we directly compare the equilibrium fluctuations, measured as "structural" relaxation in the regime of linear response, with structural recovery, i.e., field induced physical aging in the limit of a small perturbation. The two distinct correlation functions are derived from a single experiment. Because the relaxation time changes only 2% during structural recovery, no aging model is needed to analyze the results. Although being conceptually different processes, dielectric relaxation and recovery dynamics are observed to be identical for propylene glycol, whereas single-particle dynamics as seen by photon correlation spectroscopy are significantly faster. This confirms the notion that structural recovery and aging are governed by all modes observed by dielectric spectroscopy, i.e., including cross correlations, not only by single-particle dynamics. A comparison with analogous results for other materials suggests that the relation between relaxation and recovery time scales may be material specific rather than universal.

Methodology of historical and economic research experience of post-war reconstruction

The purpose of the article is a comprehensive presentation of the modern arsenal of methods of historical and economic research. Methods and tools are presented in accordance with specific research issues. This is an urgent issue of post-war economic recovery. Scientific methods are shown in unity with the functions of economic history. A set of methods and approaches was used, which made it possible to reveal the methodological arsenal of historical and economic research in unity with their functions. The combination of analysis of various tools and synthesis of methodological approaches is aimed at achieving systemic and ensuring the effectiveness of current research programs of historical experience of post-war economic reconstruction.The result of the study is the methodological support of scientific knowledge of the international experience of post-war economic reconstruction. The expediency of applying the principle of integrativity as a synthesis of empirical historical and theoretical economic knowledge is substantiated. The content of the worldview function of economic history is revealed. It is realized through demythologization and objectification of knowledge about the content and determinants of post-war reconstruction. It is shown how the cumulative function of economic history is related to the formation of the realism of economic thinking. The prognostic function of economic history is substantiated – the ability to predict future developments and directions of events on the basis of previous experience. Comparative analysis allows us to consider the dynamics of economic recovery in different countries, the development of different economic systems and their national models. Historical experience in the implementation of reconstruction plans and programs should be studied in the unity of ontological, teleological and axiological components.The value of research methods and principles is revealed with the help of historical examples. The results of the study will be useful in the study and implementation of historical experience in the post-war recovery of Ukraine’s economy.
 JEL classіfіcatіon: B40, N44, N45, O19

Spatial and temporal drivers of post-fire tree establishment and height growth in a managed forest landscape

BackgroundIn seed-obligate conifer forests of the western US, land managers need a better understanding of the spatiotemporal variability in post-fire recovery to develop adaptation strategies. Successful establishment of post-fire seedlings requires the arrival of seeds and favorable environmental conditions for germination, survival, and growth. We investigated the spatiotemporal limitations to post-fire seedling establishment and height growth in dry to moist mixed conifer forests with and without post-fire forest management treatments (salvage logging, grass seeding) in areas burned from low to high severity. In 2011, we measured post-fire seedling establishment year, juvenile density (seedlings and saplings), and height growth (annual and total) in 50 plots with six conifer species in the School Fire (2005), Blue Mountains, WA, USA. In 2021, we remeasured the plots for post-fire juvenile density and height growth.ResultsPost-fire juvenile tree densities appeared sufficient for self-replacement of forest (> 60 stems ha−1) in 96% of plots in 2021 (median 3130 stems ha−1), but densities were highly variable (range 33–100,501 stems ha−1). Annual seedling establishment was positively correlated with cooler, wetter climate conditions during the summer of germination (July–September) and the growing season of the subsequent year (April–September) for multiple tree species. We found lower juvenile densities at greater distances to seed sources and with higher grass cover, while salvage logging had no effect. Annual height growth was shorter on warmer, drier topographic positions for three species, whereas annual height growth was associated with climate variability for one species. Shifts in height class structure from 2011 to 2021 were, in part, explained by differences among species in annual height growth.ConclusionsAbundant and widespread tree seedling establishment for multiple conifer species after fire was strong evidence that most burned sites in the present study are currently on a trajectory to return to forest. However, post-fire establishment may be constrained to brief periods of cooler, wetter climate conditions following future fires. Long-term monitoring of post-fire recovery dynamics is needed to inform management activities designed to adapt forests to climate change and future disturbances, which will collectively shape future forest structure and composition.

Comparative assessment of results of D2 and D3 lymph node dissections in term of colon cancer surgery

Purpose of the study. Was to evaluate overall survival of CC patients after D2 and D3 lymph node dissections and assess the frequency of postoperative complications and dynamics of postoperative recovery.Materials and methods. The study included 50 CC patients aged 39–84 years.Results. The comparative assessment of the overall survival, frequency of postoperative complications and dynamics of postoperative recovery was performed in patients divided into 2 groups depending on the lymph node dissection extent. Group 1 included 23 patients (46 %) with D2 lymph node dissection, group 2–27 patients (54 %) with D3 lymph node dissection. 8 (16 %) patients developed complications in the early postoperative period. Patients in group 1 had grade I (5 patients) and grade IIIb (1 patient) surgical complications, according to the Clavien-Dindo classification. 2 patients in group 2 developed grade III b complications. No significant differences were found between groups in peristalsis, gases and bowel movement, starting eating and drinking. A significant increase in the number of postoperative bed-days was observed in patients who underwent open surgery, compared with the group with laparoscopic access. No statistically significant difference was found in the overall survival in patients of the two groups (p = 0.918).Conclusion. The rates of postoperative complications that required repeated surgery were comparable between the groups with D2 and D3 lymph node dissections. D3 lymph node dissection did not affect the dynamics of postoperative recovery and the overall survival of patients.

Assessment of relevance and effectiveness of remote rehabilitation methods in patients after total hip replacement

Relevance: The effectiveness and validity of rehabilitation after endoprosthetics of the lower limb joints is beyond doubt. However, the workload of operating surgeons and the high demand for rehabilitation hospitals and outpatient care limit the possibility of rehabilitation treatment, which impairs the final result of the operation. Taking into account active development of technologies, the introduction of remote-controlled rehabilitation and online questionnaires to assess the effectiveness of postoperative recovery and the quality of life of patients can be considered a promising direction for the organization of a continuous approach to rehabilitation treatment. The aim of the study was to evaluate the effectiveness of the remote rehabilitation forms and the developed questionnaires to determine the routing of patients after hip replacement. Materials and methods: The retrospective study included 30 patients aged 40 to 75 years after total hip replacement surgery. In the surgical hospital, all patients were offered the opportunity to take a survey according to the questionnaire developed by us in order to determine the group and further routing after surgery. The patients of the main group (n=15) who had the technical capabilities to engage in rehabilitation remotely were offered a link to exercise therapy complexes and a video clip on the technique of performing these exercises; online classes with a physical therapy instructor were also conducted. The rehabilitation program started from the first day after surgery and lasted 90 days. The patients of the control group (n=15) underwent classical rehabilitation in a hospital lasting 10–14 days, after which they were discharged with recommendations for outpatient follow-up. To assess the dynamics and satisfaction with postoperative recovery, all patients underwent remote testing to evaluate the quality of life and psycho-emotional state, which was carried out on the second day and 3 months after surgery. Results. The use of remote rehabilitation methods for patients after hip replacement has a positive clinical effect and is characterized by high satisfaction with the outcomes of postoperative recovery. Remote monitoring of the recovery dynamics and the creation of a database contribute to assessing the effectiveness of the treatment. Conclusion. The developed online questionnaires allow determining further routing of patients for rehabilitation treatment after surgery and evaluating the effectiveness of rehabilitation, including by means of remote rehabilitation methods. In case of paramedical difficulties in conducting full-time rehabilitation, a model of using various forms of remote rehabilitation is proposed.

A disease-specific spectral index tracks Magnaporthe oryzae infection in paddy rice from ground to space

Rice blast (RB, caused by the fungus Magnaporthe oryzae) is the most devastating disease in global rice production, and can cause significant yield losses and increasingly threaten global food security. Accurate detection of RB occurrence with a universal metric is crucial to facilitate early disease prevention and curtailing the disease expansion but has not been addressed to date. This study aimed to design a rice blast index (RIBI) for quantifying the disease index (DI) and tracking the smallholder rice blast dispersal over multiple spatial scales. To achieve this goal, a large dataset including leaf- and canopy-scale reflectance spectra and satellite imagery was acquired within the framework of seven independent campaigns over four years (2018–2021). Specifically, an extensive collection of Magnaporthe oryzae infected samples were analyzed to examine the specific spectral response to pathogen infection in paddy rice from leaf to near-ground canopy scales. Two variants of the RIBI were developed, which were RIBInir = (R753-R1102)/(R665 + R1102) and RIBIred = (R753-R1102)/(R665 + R1102) based on the single-band separability and exhaustive search of band combinations. They were subsequently evaluated for quantifying the RB occurrence from ground to space. Spatial cluster analysis was then integrated with the superior RIBI adjusted for Sentinel-2 imagery to explore the spatio-temporal dynamics of pathogen infection, and to reveal the within-field hotspots of potential rice blast dispersal in smallholder farms.The results demonstrated that both RIBInir and RIBIred exhibited high overall accuracies for the classification of infected and healthy samples at the leaf scale under greenhouse in 2018 (RIBInir: 81.41%; RIBIred: 84.62%) and 2019 (RIBInir: 81.30%; RIBIred: 90.37%) and field conditions in 2020 (RIBInir: 86.36%; RIBIred: 89.39%). Compared with traditional VIs (Near-ground: R2 < 0.47, satellite: R2 < 0.54), the RIBInir yielded improved R2 in quantifying the DI from in situ spectra to satellite imagery (Near-ground: R2 = 0.73, satellite: R2 = 0.78). The strongest DI-RIBInir relationship was attributed to the use of two near-infrared (NIR) bands that helped enhance the unique spectral responses in the NIR region induced by pathogen infection, in contrast to the extensively studied visible region. Multi-temporal analysis of Sentinel-2A derived RIBInir successfully captured the temporal dynamics of RB infection and recovery and yielded compelling maps showing the spatial propagation and attenuation of disease over time. This research opens new opportunities towards quantifying field disease occurrence and detecting the within-field hotspots of potential disease dispersal in a timely manner from publicly available satellite imagery.

Review on Pore-Scale Physics of Shale Gas Recovery Dynamics: Insights from Molecular Dynamics Simulations

Review on Pore-Scale Physics of Shale Gas Recovery Dynamics: Insights from Molecular Dynamics Simulations

No post-drought recovery of the macroinvertebrate community after five months upon rewetting of an irregularly intermittent Apennine River (Aterno River)

The combined effects of global changes and increasing water demand for human use are the main drivers of the increasing intermittence of most watercourses. The disruption of lateral, longitudinal and vertical connectivity during the dry phase in newly intermittent rivers may have dramatic effects on freshwater biota, ecosystem structure and processes and may extend its influence also after several months from the return of superficial flow. A few studies have systematically documented the dynamics of post-drought recovery of freshwater communities. In this paper we assessed the temporal dynamics of benthic invertebrate's recovery starting from the first day after superficial flow resumption and for the successive five months. We demonstrated that the recolonization process of rewetted substrata was very low and partial, and after five months from the return of superficial flow the richness and abundance of post-drought re-colonizers were markedly lower if compared with the pre-drought community and with that of a near upstream perennial site. In this context, upstream drift, “seedbanks” and hyporheic refugia would be of minor importance and the observed recolonization pattern may be mainly explained by the aerial dispersal from downstream perennial reaches of tolerant and generalist taxa. Therefore, former perennial Apennine rivers may be profoundly affected by modifications of the natural flow regime. Increasing intermittence of these watercourses may determine drastic changes in community structure and composition, with species loss and species substitution. In addition, the high post-drought functional turnover may have negative effects on key ecosystem processes as leaf-litter breakdown and primary production.

Detection and Quantification of Protein Aggregates in Plants.

Protein quality control is an important aspect of stress recovery. It maintains protein homeostasis through a machinery of regulatory proteins such as chaperones and proteases. When the system recognizes accumulation of misfolded or aggregated proteins, the cell recruits a set of regulatory proteins to initiate protein quality control. To understand the dynamics of stress-mediated aggregate protein formation and recovery in plants, robust methods aimed at detecting and measuring such protein aggregates are needed. This will help us to deepen our understanding of protein quality control mechanisms in plants.

Recovery dynamics of ecosystem carbon budgets in a young silver birch stand chronosequence after clear-cut – Estonian case study

ABSTRACT Clear-cutting is an extensively used silvicultural method in the Nordic and Baltic countries, which strongly influences the site’s carbon (C) budget. In the current study, C budgets for a young silver birch stand chronosequence (2–8-year-old) were compiled using the C budgeting method. High variability of annual NEP between stands of similar ages occurred, as the C accumulation ability of young stands was site specific. Heterotrophic respiration (Rh), the main C efflux from the ecosystem, varied between (3.7 and 6.3 t C ha−1 yr−1) across all stands. Modelling of the annual NEP dynamics across the chronosequence revealed the C compensation point at a stand age of 6 years. The estimated cumulative C loss for the period when NEP was negative was almost 5 t C ha−1 and the amount of lost C could have been recaptured already in a 10-year-old stand. The C sink capacity of the studied sites depended mostly on the production of herbaceous plants until the production of the new tree generation became the main driver of ecosystem’s net primary production. Hence, site’s C accumulation capacity largely depends on the density and quality of the new forest regeneration.

Invasion reversal by front transitions and their implications for ecosystem management

Alien species often become invasive by triggering the growth of pathogens that exert a strong negative effect on the native species. Using an extended Lotka–Volterra plant competition model that includes pathogen dynamics with a strong Allee effect we identify a bistability range of counter-propagating fronts representing invasion and recovery dynamics. The fronts differ in the levels of the pathogen in the front zone; high, beyond the Allee threshold for the invasion front and low, below that threshold for the recovery front. Invasion reversal is then studied as induced transitions from invasion fronts to recovery fronts. The study suggests managing invasion by local manipulations in the front zone that increase the Allee threshold and thereby reverse the front from invasion to recovery. We demonstrate numerically direct and indirect manipulations of this kind.

Experimental Correction of Homeostasis Changes during Alloxan-Induced Diabetes by Implantation of Islet Cells Cultured in Fibrous TiNi-Based Scaffold.

The use of fibrous scaffolds made of titanium nickelide and carrying islet cells (IC) after a course of alloxan administration was studied in vivo. Scanning electron microscopy showed good adhesion of IC in the pore space of the scaffolds. In 28 days, mature tissue comprising both cellular and fibrous components filled the inner space of the scaffold by 90%. The advantage of intraperitoneal implantation of IC in vitro seeded in fibrous titanium nickelide scaffolds in comparison with injection of IC (6×105 cells) to Wistar rats was demonstrated in the dynamics of pancreatic function recovery (normalization of blood glucose and glycosylated hemoglobin concentrations by day 21 of the experiment), regeneration of the white hematopoietic lineage cells, and lengthening (by 2 times) of the lifespan of animals with alloxan-induced diabetes. Injection of IC improved rat survival by only 40%. Thus, the hybrid tissue-engineered construct (fibrous titanium nickelide scaffold+IC) is biocompatible when administered intraperitoneally, stimulates regeneration in rats with alloxan-induced diabetes, improves blood glucose utilization processes, and restores suppressed leukopoiesis. It is assumed that hepatocytes can be the main target cells of the hybrid tissue-engineering construct.

Influence of physical loading on behavioral reactions of rats in cerebral hypoperfusion

A number of clinical studies demonstrate that individual characteristics such as stress tolerance and cognitive ability can be considered not only as diagnostic variables but also as risk factors for severe cerebral hypoperfusion. The aim of the study was to identify the typological features of the effect of physical activity on the behavioral reactions of rats during cerebral hypoperfusion. Material and methods. Cerebral hypoperfusion was modeled by bilateral carotid artery ligation. The study involved 280 rats, divided into equal subgroups, according to sex, stress tolerance and learning capacity. Of these, 112 animals were subjected to daily short-term swimming as a rehabilitation model. Before the simulation, and at 6, 8, 14, 21, 28, 35, 60 and 90 days postoperatively, the animals were tested using a Morris water maze and an “open field” test. Results and discussion. The dynamics of stress resistance and learning ability are related to the periodicity of inflammatory, necrotic, circulatory and reparative remodeling in the model used. After 2-3 months of study, cerebral hypoperfusion causes stabilization of indices characterizing stress resistance and cognitive functions below control values. A decrease in stress resistance begins earlier from day 6 of the study, while the index characterizing cognitive functions first decreases significantly after 3 weeks of study. Factors reducing the damaging effects of cerebral hypoperfusion were female gender, high baseline stress tolerance and learning ability. When assessing learning ability under physical load, animals with high baseline cognitive development showed earlier recovery dynamics during urgent adaptation and a significant increase during long-term adaptation.