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Chagas disease, a neglected global health concern primarily transmitted through the bite and feces of kissing bugs, has garnered increasing attention due to recent outbreaks in northern Brazil, highlighting the role of oral transmission facilitated by the kissing bugs species Rhodnius robustus and Rhodnius pictipes. These vectors are associated with palm trees with large crowns, such as the maripa palm (Attalea maripa) and moriche palm (Mauritia flexuosa). In this study, we employ maximum entropy (MaxEnt) ecological niche models to analyze the spatial distribution of these vectors and palm species, predicting current and future climate suitability. Our models indicate broader potential habitats than documented occurrences, with high suitability in northern South America, southern Central America, central Africa, and southeast Asia. Projections suggest increased climate suitability by 2040, followed by a reduction by 2080. This study identifies present and future areas suitable for kissing bugs and palm tree species due to climate change, aiding in the design of prevention and management strategies.

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Obesity is a chronic disease caused by excessive fat accumulation that impacts the body and brain health. Insufficient leptin or leptin receptor (LepR) is involved in the disease pathogenesis. Leptin is involved with several neurological processes, and it has crucial developmental roles. We have previously demonstrated that leptin deficiency in early life leads to permanent developmental problems in young adult mice, including an imbalance in energy homeostasis, alterations in melanocortin and the reproductive system and a reduction in brain mass. Given that in humans, obesity has been associated with brain atrophy and cognitive impairment, it is important to determine the long-term consequences of early-life leptin deficiency on brain structure and memory function. Here, we demonstrate that leptin-deficient (LepOb) mice exhibit altered brain volume, decreased neurogenesis and memory impairment. Similar effects were observed in animals that do not express the LepR (LepRNull). Interestingly, restoring the expression of LepR in 10-week-old mice reverses brain atrophy, in addition to neurogenesis and memory impairments in older animals. Our findings indicate that leptin deficiency impairs brain development and memory, which are reversible by restoring leptin signalling in adulthood.

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SARS-CoV-2 infection in children is usually asymptomatic/mild. However, some patients may develop critical forms. We aimed to describe characteristics and evaluate the factors associated to in-hospital mortality of patients with critical COVID-19/MIS-C in the Amazonian region. This multicenter prospective cohort included critically ill children (1 mo-18 years old), with confirmed COVID-19/MIS-C admitted to 3 tertiary Pediatric Intensive Care Units (PICU) in the Brazilian Amazon, between April/2020 and May/2023. The main outcome was in-hospital mortality and were evaluated using a multivariable Cox proportional regression. We adjusted the model for pediatric risk of mortality score version IV (PRISMIV) score and age/comorbidity. 266 patients were assessed with 187 in the severe COVID-19 group, 79 included in the MIS-C group. In the severe COVID-19 group 108 (57.8%) were male, median age was 23 months, 95 (50.8%) were up to 2 years of age. Forty-two (22.5%) patients in this group died during follow-up in a median time of 11 days (IQR, 2-28). In the MIS-C group, 56 (70.9%) were male, median age was 23 months and median follow-up was 162 days (range, 3-202). Death occurred in 17 (21.5%) patients with a median death time of 7 (IQR, 4-13) days. The mortality was associated with higher levels of Vasoactive Inotropic-Score (VIS), presence of acute respiratory distress syndrome (ARDS), higher levels of Erythrocyte Sedimentation Rate, (ESR) and thrombocytopenia. Critically ill patients with severe COVID-19 and MIS-C from the Brazilian Amazon showed a high mortality rate, within 12 days of hospitalization.

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The aim was to evaluate the effects of Nest Positioning (NP) on motor development, sleep patterns, and weight gain in preterm newborns (PTNB) hospitalized in a neonatal intensive care unit (NICU). This study was constructed based on PRISMA guideline criteria. Systematic research was carried out in electronic databases: MEDLINE via PubMed, Web of Science, Scopus, and VHL-BIREME following the PICOS strategy. Studies with PTNB populations who were hospitalized in the NICU and received therapeutic NP as an intervention strategy in this population were included in this study. We sought outcomes related to sleep patterns, weight gain, and motor development. After selection, 12 studies were included in this systematic review, of which 5 (41.7%) evaluated motor development as their primary outcome, 6 (50%) sleep-wake cycle patterns, and 1 (8.3%), weight gain and, subsequently, hospital discharge. Qualitative results indicate that prolonged exposure to decubitus variations may favor PTNB hospitalized in NICUs acquiring flexor postures, stimulate their midline, and increase their total sleep time. Studies reported no adverse effects regarding the use of NP. Evidence suggests that NP benefits motor development and sleep pattern in PTNB hospitalized in NICUs. IMPACT: Nest positioning improves sleep quality in preterm newborns hospitalized in neonatal intensive care unit. Nest positioning improves motor development in preterm newborns hospitalized in neonatal intensive care unit. No evidence of nest positioning on weight gain was observed. Half of the included clinical studies showed good methodological quality. Nesting positioning is a secure and cost-effective method.

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Forest ecosystems play an important role in mitigating the concentration increase of carbon dioxide (CO2) in the atmosphere through carbon sequestration by plants and its storage in biomass and soil. The objective was to determine the aerial biomass carbon stock in a dry tropical forest in Brazil. It was developed between 2012 to 2015, in an area with an advanced regeneration stage (50 years) in the semi-arid region of Pernambuco and it was used 40 permanent plots (400 m²) distant 80 m apart, with 50 m from the border, totaling 1.6 ha of the area to sample the shrubby-arboreal component, where all individuals with circumference at breast height (1.30 m of the soil) equal or greater than 6 cm were identified, measured and labeled in 2012 and remeasured in 2015. It was calculated the biomass and carbon stocks through developed equations available in the literature. The results showed that the total biomass and carbon stock in the first year was 27.97 e 12.92 Mg.ha-1 while in 2015 it was 18.49 and 8.39 Mg.ha-1 respectively. The results showed a biomass and carbon stock reduction of more than 30% in the period evaluated, even this, the area manages to present values within the expected pattern for the region, assuring the importance of sustainable forest management of these native/natural vegetation areas.

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Tropical ectotherms are highly sensitive to environmental warming, especially coral reef fishes, which are negatively impacted by an increase of a few degrees in ocean temperature. However, much of our understanding on the thermal sensitivity of reef fish is focused on a few traits (e.g., metabolism, reproduction) and we currently lack knowledge on warming effects on cognition, which may endanger decision-making and survival. Here, we investigated the effects of warming on learning and memory in a damselfish species, Acanthochromis polyacanthus. Fish were held at 28-28.5 °C (control group), 30-30.5 °C (moderate warming group) or 31.5-32 °C (high warming group) for 2 weeks, and then trained to associate a blue tag (cue) to the presence of a conspecific (reward). Following 20 training trials (5 days), fish were tested for associative learning (on the following day) and memory storage (after a 5-days interval). The control group A. polyacanthus showed learning of the task and memory retention after five days, but increasing water temperature impaired learning and memory. A thorough understanding of the effects of heat stress, cognition, and fitness is urgently required because cognition may be a key factor determining animals' performance in the predicted scenario of climate changes. Knowing how different species respond to warming can lead to better predictions of future community dynamics, and because it is species specific, it could pinpoint vulnerable/resilience species.

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Peptidoglycan (PG) is a central component of the bacterial cell wall, and the disruption of its biosynthetic pathway has been a successful antibacterial strategy for decades. PG biosynthesis is initiated in the cytoplasm through sequential reactions catalyzed by Mur enzymes that have been suggested to associate into a multimembered complex. This idea is supported by the observation that in many eubacteria, mur genes are present in a single operon within the well conserved dcw cluster, and in some cases, pairs of mur genes are fused to encode a single, chimeric polypeptide. We performed a vast genomic analysis using >140 bacterial genomes and mapped Mur chimeras in numerous phyla, with Proteobacteria carrying the highest number. MurE-MurF, the most prevalent chimera, exists in forms that are either directly associated or separated by a linker. The crystal structure of the MurE-MurF chimera from Bordetella pertussis reveals a head-to-tail, elongated architecture supported by an interconnecting hydrophobic patch that stabilizes the positions of the two proteins. Fluorescence polarization assays reveal that MurE-MurF interacts with other Mur ligases via its central domains with KDs in the high nanomolar range, backing the existence of a Mur complex in the cytoplasm. These data support the idea of stronger evolutionary constraints on gene order when encoded proteins are intended for association, establish a link between Mur ligase interaction, complex assembly and genome evolution, and shed light on regulatory mechanisms of protein expression and stability in pathways of critical importance for bacterial survival.

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INTRODUCTION: Extracellular vesicles (EVs) have been implicated in the spread of neuropathology in Alzheimer's disease (AD), but their involvement in behavioral outcomes linked to AD remains to be determined. METHODS: EVs isolated from post mortem brain tissue from control, AD, or frontotemporal dementia (FTD) donors, as well as from APP/PS1 mice, were injected into the hippocampi of wild-type (WT) or a humanized Tau mouse model (hTau/mTauKO). Memory tests were carried out. Differentially expressed proteins in EVs were assessed by proteomics. RESULTS: Both AD-EVs and APP/PS1-EVs trigger memory impairment in WT mice. We further demonstrate that AD-EVs and FTD-EVs carry Tau protein, present altered protein composition associated with synapse regulation and transmission, and trigger memory impairment in hTau/mTauKO mice. DISCUSSION: Results demonstrate that AD-EVs and FTD-EVs have negative impacts on memory in mice and suggest that, in addition to spreading pathology, EVs may contribute to memory impairment in AD and FTD. HIGHLIGHTS: Aß was detected in EVs from post mortem AD brain tissue and APP/PS1 mice. Tau was enriched in EVs from post mortem AD, PSP and FTD brain tissue. AD-derived EVs and APP/PS1-EVs induce cognitive impairment in wild-type (WT) mice. AD- and FTD-derived EVs induce cognitive impairment in humanized Tau mice. Proteomics findings associate EVs with synapse dysregulation in tauopathies.

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Plant genomes are comprised of nuclear, plastid and mitochondrial components characterized by different patterns of inheritance and evolution. Genetic markers from the three genomes provide complementary tools for investigations of inheritance, genetic relationships and phenotypic contributions. Plant mitochondrial genomes are challenging for universal marker development because they are highly variable in terms of size, gene order and intergenic sequences and highly conserved with respect to protein-coding sequences. PCR amplification of introns with primers that anneal to conserved, flanking exons is effective for the development of polymorphic nuclear genome markers. The potential for plant mitochondrial intron polymorphisms to distinguish between congeneric species or intraspecific varieties has not been systematically investigated and is possibly constrained by requirements for intron secondary structure and interactions with co-evolved organelle intron splicing factors. To explore the potential for broadly applicable plant mitochondrial intron markers, PCR primer sets based upon conserved sequences flanking 11 introns common to seven angiosperm species were tested across a range of plant orders. PCR-amplified introns were screened for indel polymorphisms among a group of cross-compatible Citrus species and relatives; two Raphanus sativus mitotypes; representatives of the two Phaseolus vulgaris gene pools; and congeneric pairs of Cynodon, Cenchrus, Solanum, and Vaccinium species. All introns were successfully amplified from each plant entry. Length polymorphisms distinguishable by gel electrophoresis were common among genera but infrequent within genera. Sequencing of three introns amplified from 16 entries identified additional short indel polymorphisms and nucleotide substitutions that separated Citrus, Cynodon, Cenchrus and Vaccinium congeners, but failed to distinguish Solanum congeners or representatives of the Phaseolus vulgaris major gene pools. The ability of primer sets to amplify a wider range of plant species' introns and the presence of intron polymorphisms that distinguish congeners was confirmed by in silico analysis. While mitochondrial intron variation is limited in comparison to nuclear introns, these exon-based primer sets provide robust tools for the amplification of mitochondrial introns across a wide range of plant species wherein useful polymorphisms can be identified.

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Obesity is defined as abnormal or excessive fat accumulation that may impair health and is a risk factor for developing other diseases, such as type 2 diabetes and cardiovascular disorder. Obesity is also associated with structural and functional alterations in the brain, and this condition has been shown to increase the risk of Alzheimer's disease. However, while obesity has been associated with neurodegenerative processes, its impact on brain cell composition remains to be determined. In the current study, we used the isotropic fractionator method to determine the absolute composition of neuronal and non-neuronal cells in different brain regions of the genetic mouse models of obesity Lepob/ob and LepRNull/Null . Our results show that 10- to 12-month-old female Lepob/ob and LepRNull/Null mice have reduced neuronal number and density in the hippocampus compared to C57BL/6 wild-type mice. Furthermore, LepRNull/Null mice have increased density of non-neuronal cells, mainly glial cells, in the hippocampus, frontal cortex and hypothalamus compared to wild-type or Lepob/ob mice, indicating enhanced inflammatory responses in different brain regions of the LepRNull/Null model. Collectively, our findings suggest that obesity might cause changes in brain cell composition that are associated with neurodegenerative and inflammatory processes in different brain regions of female mice.

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Strontium acetate is applied for dental hypersensitivity treatment; however, the use of strontium carbonates for this purpose has not been described. The use of Sr-carbonate nanoparticles takes advantage of both the benefits of strontium on dentin mineralization and the abrasive properties of carbonates. Here in, we aimed to synthesize strontium carbonate and strontium-substituted calcium carbonate nanoparticles and test them as potential compounds in active dentifrices for treating dental hypersensitivity. For this, SrCO3, Sr0.5Ca0.5CO3, and CaCO3 nanoparticles were precipitated using Na2CO3, SrCl2, and/or CaCl2 as precursors. Their morphology and crystallinity were evaluated by electron microscopy (SEM) and X-ray diffraction, respectively. The nanoparticles were added to a poly (vinyl alcohol) gel and used to brush dentin surfaces isolated from human third molars. Dentin chemical composition before and after brushing was investigated by infrared spectroscopy (FTIR) and X-ray dispersive energy spectroscopy. Dentin tubule morphology, obliteration, and resistance of the coatings to acid attack were investigated by SEM and EDS. The cytotoxicity and ability of the particles to trigger the mineralization of hDPSCs in vitro were studied. Dentin brushed with the nanoparticles was coated by a mineral layer that was also able to penetrate the tubules, while CaCO3 remained as individual particles on the surface. FTIR bands related to carbonate groups were intensified after brushing with either SrCO3 or Sr0.5Ca0.5CO3. The shift of the phosphate-related FTIR band to a lower wavenumber indicated that strontium replaced calcium on the dentin structure after treatment. The coating promoted by SrCO3 or Sr0.5Ca0.5CO3 resisted the acid attack, while calcium and phosphorus were removed from the top of the dentin surface. The nanoparticles were not toxic to hDPSCs and elicited mineralization of the cells, as revealed by increased mineral nodule formation and enhanced expression of COL1, ALP, and RUNX2. Adding Sr0.5Ca0.5CO3 as an active ingredient in dentifrices formulations may be commercially advantageous since this compound combines the well-known abrasive properties of calcium carbonate with the mineralization ability of strontium, while the final cost remains between the cost of CaCO3 and SrCO3. The novel Sr0.5Ca0.5CO3 nanoparticles might emerge as an alternative for the treatment of dental hypersensitivity.

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Anthropogenic noises are widespread and affect marine wildlife. Despite the growing knowledge on noise pollution in the marine environment, its effects on fish cognition are scarce. Here, we investigated the effects of sound exposure on anxiety-like behavior and memory retention on dusky damselfish Stegastes fuscus. The animals were trained in a conditioned place aversion task, and exposed to two daily sessions of music at intensities of 60-70 dBA or 90-100 dBA, while the control group was kept at 42-46 dBA (no music) for five days. After that, fish were tested in the novel tank paradigm and tested for the memory of the aversive task. In the novel tank, animals exposed to sound spent more time still and decreased the distance from the bottom of the tank. Animals also spent more time on the aversive side of the conditioning tank. These results suggest that anthropogenic noise applied through high-intensity music can increase anxiety and decrease memory retention in S. fuscus, suggesting the deleterious potential of noise for reef species.

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Huanglongbing (HLB), caused by 'Candidatus Liberibacter asiaticus' (CLas), is a devastating disease of citrus. After initial infection, CLas quickly colonizes the root system before canopy symptoms develop. There is limited understanding of CLas movement from roots to canopy and local and systemic effects on root dynamics. Using split-root rhizoboxes and late summer below-the-split bud inoculation, effects of local infection on systemic disease development were studied. Upward bacterial movement from roots is linked to seasonal flushes and CLas population in roots. CLas stayed isolated to one side of the roots for at least 8 months, until the spring flush. HLB caused differential root responses depending on tree age at infection. Systemic effects, independent of CLas movement, occur very early after infection. Stimulation of root growth occurred on noninfected roots prior to CLas detection in 1.5-year-old trees but decreased in 2.5-year-old trees. Independent of tree age, root growth was stimulated during spring root flushes after CLas population stabilized. Root dieback began simultaneously with detection of CLas in roots (6 weeks postinoculation). Infection and tree age altered root lifespan. In total, 1.5-year-old CLas-infected roots from summer and fall flushes had 3 and 6 weeks reduced lifespan. In contrast, 2.5-year-old CLas-infected plants lifespan was unaffected. Season affected root lifespan with late summer root flush lifespan was three times shorter than fall or spring root flushes. Split-root inoculation allowed study of local and systemic effects of CLas infection in roots, information crucial to prolonging the productivity of HLB-affected trees.

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OBJECTIVE: To assess the acute response of cardiac autonomic modulation (ACAM) during and after a session of virtual reality-based therapy (VRBT) compared to a session of conventional cardiovascular rehabilitation (CR) and to evaluate the effects of 12 weeks of training on this response. METHODS: We assessed 28 volunteers (63.4 ± 12.5 years). The ACAM was judged by linear indexes of heart rate variability (HRV) in VRBT and CR sessions. Later, patients completed 12 weeks of VRBT+CR and the assessment was repeated at the 12th week. RESULTS: Throughout the 1st VRBT session vagal withdrawal occurred (RMSSD/HFnu); sympathetic nervous system stimulation (LFnu) and progressive decrease of global HRV (SDNN). During the recovery, the SDNN, HFnu, and LFnu improved from the 5thminute on both therapies. After 12 weeks, the LFnu, HFnu, and the LF/HF-ratio revealed no significant changes in Ex3-Ex4 equated to Rep during VRBT. In recovery, the HFnu and LFnu improved before the 5thminute on both therapies. CONCLUSIONS: ACAM during and after the VRBT was comparable to CR, yet, the extents were greater in the VRBT. After 12 weeks of VRBT training, the subjects adapted to the exercises from the 15thminute and exhibited faster recovery of HFnu and LFnu indexes compared to the 1st week.

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The comparison of chemical and histopathological data obtained from the analysis of excised tumor fragments oral squamous cell carcinoma (OSCC) with the demographic and clinical evolution data is an effective strategy scarcely explored in OSCC studies. The aim was to analyze OSCC tissues for protein expression of enzymes related to oxidative stress and DNA repair and trace elements as candidates as markers of tumor aggressiveness and prognosis. Tumor fragments from 78 OSCC patients that had undergone ablative surgery were qualitatively analyzed by synchrotron micro-X-ray fluorescence for trace elements. Protein expression of SOD-1, Trx, Ref-1 and OGG1/2 was performed by immunohistochemistry. Sociodemographic, clinical, and histopathological data were obtained from 4-year follow-up records. Disease relapse was highest in patients with the presence of chlorine and chromium and lowest in those with tumors with high OGG1/2 expression. High expression of SOD-1, Trx, and Ref-1 was determinant of the larger tumor. Presence of trace elements can be markers of disease prognosis. High expression of enzymes related to oxidative stress or to DNA repair can be either harmful by stimulating tumor growth or beneficial by diminishing relapse rates. Interference on these players may bring novel strategies for the therapeutic management of OSCC patients.

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The diversity of endotherms and ectotherms may be differently affected by ambient temperature and net primary productivity (NPP). Additionally, little is known about how these drivers affect the diversity of guilds of different trophic levels. We assessed the relative role of temperature and NPP in multitrophic guilds of ectothermic (arthropods: ants, ground beetles, spiders, and harvestmen) and endothermic (large mammals) animals along a tropical elevational gradient. We sampled arthropods at eight elevation belts and large mammals at 14 elevation belts in Atlantic rainforest (ranging from 600 to 2450 m.a.s.l.) of Itatiaia National Park, Southeast Brazil. Overall arthropod species richness was more associated with temperature than overall large-mammal species richness, while the latter was more associated with NPP. When separated into trophic guilds, we found that the species richness associated with NPP increased across arthropod trophic levels from herbivores to predators. Conversely, although NPP influenced large-mammal herbivore species richness, its effects did not seem to accumulate across large-mammal trophic levels since the species richness of large-mammal omnivores was more associated with temperature and none of the variables we studied influenced large-mammal predators. We suggest that thermal physiological differences between ectotherms and endotherms are responsible for the way in which arthropods and large mammals interact with or are constrained by the environment. Furthermore, the inconsistency regarding the role of temperature and NPP on species richness across multitrophic guilds of ectotherms and endotherms could indicate that thermal physiological differences might also interfere with energy use and flux in the food web.

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The elongasome, or Rod system, is a protein complex that controls cell wall formation in rod-shaped bacteria. MreC is a membrane-associated elongasome component that co-localizes with the cytoskeletal element MreB and regulates the activity of cell wall biosynthesis enzymes, in a process that may be dependent on MreC self-association. Here, we use electron cryo-microscopy and X-ray crystallography to determine the structure of a self-associated form of MreC from Pseudomonas aeruginosa in atomic detail. MreC monomers interact in head-to-tail fashion. Longitudinal and lateral interfaces are essential for oligomerization in vitro, and a phylogenetic analysis of proteobacterial MreC sequences indicates the prevalence of the identified interfaces. Our results are consistent with a model where MreC's ability to alternate between self-association and interaction with the cell wall biosynthesis machinery plays a key role in the regulation of elongasome activity.

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BACKGROUND: Mental fatigue seems to impair the athletes' performance; however, in sports with high cognitive demand, such as orienteering, this negative effect could be attenuated during the race. Therefore, this study investigated mental fatigue effect on performance, perceptual, and physiological responses in orienteers. METHODS: Fifteen male orienteers (30±8 years) participated in the study. Two conditions of cognitive tasks preceded the orienteering performance, performed randomly: 30 minutes of mental exertion (experimental condition [EXP]) by Stroop task, or 30 min without mental exertion (control condition [CON]). Orienteering performance was determined by the time required to perform the Orienteering race. The perceived recovery and motivation were evaluated in each condition, pre-cognitive task, and heart rate during the task. Perceived exertion (RPE) was measured pre- and post-orienteering race. Orienteering performance and perceived performance were measured immediately after the race. RESULTS: Orienteering performance and remain variables showed no significant differences between conditions (EXP versus CON) (P>0.05). Although a slight increase in performance-time was found in EXP (40.8±11.4 min) versus CON (38.4±13 min) (P=0.4; ES=0.20). RPE increase post-EXP (P<0.05; ES=0.96) but not post-orienteering race (P>0.05). CONCLUSIONS: Thirty minutes of the cognitive task did not significantly affect the perceptual and physiological responses but demonstrates the addition of 2.4 minutes to orienteering performance. Orienteers may cope with mental effort due to the cognitive demands and physical conditions required in orienteering.

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