Search Results (72)

Edge, fog, and cloud continuum architectures that interconnect resource-constrained devices, intermediate edge servers, and remote cloud data centers face persistent challenges in handling heterogeneous and latency-sensitive workloads while reducing energy consumption and improving resource utilization. Classical task offloading approaches either rely on static heuristics, which lack adaptability to dynamic conditions, or on metaheuristic optimizers, which often incur high computational overhead and centralized coordination. This paper proposes LITO, a lemur-inspired task offloading algorithm for edge, fog, and cloud continuum systems that models the infrastructure as a social system in which computing nodes assume distinct roles that mirror lemur social hierarchies. Building on an abstracted model of lemur group behavior, LITO incorporates two key lemur-inspired mechanisms: an energy-aware task assignment mechanism based on sun basking, a thermoregulation behavior in which lemurs seek favorable warm spots, mapped here to selecting energetically efficient execution nodes, and a cooperative scheduling policy based on huddling, group clustering under stress, mapped here to sharing load among overloaded nodes. These mechanisms are combined with a continual supervised policy-learning layer with contextual bandit feedback that refines offloading decisions from online feedback. The resulting multi-objective formulation jointly minimizes energy consumption and deadline violations while maximizing resource utilization and throughput under high-load conditions in the edge and fog segment of the continuum. Simulations under diverse workload regimes and task complexities show that LITO outperforms representative multi-objective offloading baselines in terms of energy consumption, resource utilization, latency, Service Level Agreement (SLA) violations, and throughput in congested scenarios. Full article

The lemur tree frog (Agalychnis lemur), a critically endangered species, can benefit from ex situ conservation programs; however, managing amphibians under human care presents challenges, including the provision of appropriate nutrition. House crickets (Acheta domesticus), a common feeder insect, have an inverse calcium to phosphorus ratio (Ca:P; 0.15:1) and low calcium content (<0.3%). While gut-loading crickets with an 8% calcium diet can improve their calcium concentrations, no study has assessed the effects of dietary calcium on bone development in Agalychnis spp. Moreover, no study has examined how diet impacts the gut–skin axis and skin microbiome of these frogs. This study examined how crickets gut-loaded with either a 1.3% or 8% calcium diet affected lemur tree frog bone density and skin microbiome. We hypothesized that frogs consuming the 8% calcium diet would exhibit significantly higher Hounsfield units (HU; bone density) over time, as measured by micro-computed tomography (mCT), and that dietary calcium concentration would have no effect on skin bacterial and fungi microbiomes. Eleven juvenile lemur tree frogs underwent mCT scans at baseline and 90 and 180 days. Total body volume of interest analysis showed a significant increase in HU in the 8% calcium group compared to the 1.3% group (F = 9.9, p = 0.01). There was no significant difference noted in the alpha or beta diversities for the bacterial and fungal microbiomes between dietary groups. This study provides the first evidence of dietary calcium’s impact on bone density in lemur tree frogs, offering valuable insights for improving ex situ management of this species. Full article

The cornea is essential for proper ocular function, yet its histological structure varies considerably among animal species. Of particular importance are the palisades of Vogt in the limbal region, as they serve as a niche for limbal epithelial stem cells involved in corneal epithelial regeneration. This study was conducted on 73 eyeballs collected from 18 species of non-human primates originating from the Wrocław Zoological Garden (Poland). Eyeballs were fixed, processed, and embedded in paraffin. Four-micrometer sections were stained with Mayer’s H&E and PAS. Microscopically, the cornea showed either a four-layered pattern (anterior corneal epithelium, corneal stroma, Descemet’s membrane, posterior corneal epithelium) or a five-layered pattern when Bowman’s layer was present. A four-layered cornea occurred in the ring-tailed lemur, gray mouse lemur, Guianan squirrel monkey, Angolan colobus, and L’Hoest’s monkey, while the remaining species showed a five-layered structure with Bowman’s layer. The anterior corneal epithelium varied between species in thickness and number of cell layers (central region: 2–3 to 10–15 layers; 11.81 ± 0.43 µm to 44.23 ± 0.69 µm; peripheral region: 4–5 to 9–11 layers; 8.63 ± 2.57 µm to 42.45 ± 8.61 µm). Bowman’s layer ranged from 1.18 ± 0.01 µm to 3.22 ± 0.05 µm. The corneal stroma thickness differed markedly (237.96 ± 9.64 µm to 1438.29 ± 16.38 µm), as did Descemet’s membrane (4.92 ± 0.20 µm to 43.45 ± 0.49 µm), along with PAS reaction intensity. In the limbus, palisades of Vogt ranged from weakly to clearly developed; well-defined crypt-like structures were observed in the red-bellied lemur, red ruffed lemur, black-and-white ruffed lemur, Guianan squirrel monkey, L’Hoest’s monkey, Celebes crested macaque, and yellow baboon. The limbal epithelium also varied in thickness (5–6 to 15–17 cell layers). These results confirm distinct species-specific differences in corneal and limbal morphology that may reflect ecological conditions and functional adaptation. The presented data provides a comparative reference for veterinary ophthalmology and for studies on corneal epithelial regeneration involving limbal stem cells. Full article

Conservation of the gallery forest in Berenty Reserve is becoming increasingly urgent. Any deterioration threatens its increasingly rare lemur species. Following a trial planting programme started in 2016 on three plots, with measurement of seedling growth in 2017 and 2018, we returned in 2025 to measure the changes in height, canopy cover and stem diameter. Key insights were that growth had accelerated markedly after 2018. Trees in the forest can be divided into three main species groups—upper canopy, lower canopy and dryland species—but we found scant relationship between species growth and their eventual canopy height, which could have consequences for future planting schemes and management. The plots in the mid-forest showed the highest growth rates. Mortality of seedlings was highest on the riverside plot, but there was also wild recruitment from the forest. The plots by the river and in the mid-forest received the largest number of recruits. The chief problem for the study was that we were only in Berenty for short periods and could not oversee ongoing activities in the plant nursery and in the forest. Consequently, there were problems arising from nursery treatment, unrecorded replanting and difficulties tracking the growth of individuals across years. Future work, based on our results, will focus on identifying and planting species best suited for recovery on the varied sites. Overall, temporal depth is essential for making appropriate restoration decisions based on long-term ecological functioning. Full article

In September 2024, an acute hemorrhagic diarrhea occurred in a colony of captive ring-tailed lemurs (Lemur catta) housed adjacent to an enclosure of squirrel monkeys in Henan Province, China. Three of the ring-tailed lemurs (1-year-old females) died, and necropsy revealed severe cecal hemorrhage. Histopathology demonstrated extensive mucosal necrosis, hemorrhage, and inflammatory cell infiltration in the cecum, with parasite adhesion and invasion into the crypts. Microscopic examination and PCR targeting the ITS1-5.8S-ITS2 region (347 bp) confirmed the presence of T. mobilensis in the deceased lemurs’ intestinal contents and in feces from 40.0% (4/10) of the squirrel monkeys. Ultrastructural analysis (SEM/TEM) confirmed that the isolated parasites exhibited the morphology and key features of T. mobilensis, including prominent peripheral hydrogenosomal vesicles. Treatment with metronidazole and supportive care led to the recovery of the surviving lemurs. Post-treatment fecal exams of ring-tailed lemur were negative for T. mobilensis. This report provides the first evidence of T. mobilensis infection in ring-tailed lemurs, indicating cross-species transmission from squirrel monkeys to lemurs, likely facilitated by keeper-mediated mechanical transmission via tools and footwear that were used in both enclosures. Full article

CEACAMs are involved in a variety of physiological processes including cell adhesion, regulating the immune system, serving as entry receptors for a variety of pathogens, and regulating insulin receptor levels. Earlier studies identified five peptides from the N domain of human CEACAM1 that have stimulatory activity on human neutrophils. We compared the CEACAM N domain sequences, and also the amino acid sequences of the five CEACAM1 N domain peptides with biological activity in human neutrophils, among selected primates. Close similarity of the N domains was observed in the primates examined. The CEACAM1 N domains were more similar within great apes, Old World monkeys, New World monkeys, and lemurs/tarsiers than between groups. Differences in the amino acid sequences of some active peptides were observed among species; some differences are predicted to result in a loss of activity in the human neutrophil system. One amino acid change in the CD66a-1 peptide region that results in the loss of neutrophil activating activity in humans was observed in bonobos but not in the closely related chimpanzee which inhabits the opposite side of the Congo river. The same amino acid change was found to be a very rare event in humans. Changes in the CD66a-2 and CD66a-3 peptide regions were also observed in select human populations, some of which were differentially present in the chimpanzee and bonobo, as well as others that were not found in the other primates studied. In addition, a haplotype involving SNPs resulting in amino acid changes immediately adjacent to peptides CD66a-1, 3, and 7 were found in select human populations. Since CEACAM1 serves as a receptor for multiple infectious agents, selective pressure of an unidentified pathogen could be responsible for these differences. Given the diverse activities of CEACAM1 in humans, variant alleles in these domains might also have diverse effects in different populations. Full article

The gut microbiota plays a crucial role in the health and well-being of primates. This study applied 16S rRNA high-throughput sequencing technology, aiming to investigate the differences in gut microbiota composition and function between captive ring-tailed lemurs (Lemur catta) in different zoos across the north–south demarcation line in China. Results revealed significant differences in gut microbiota composition between northern and southern groups. Alpha diversity indices were higher in the southern group (p < 0.05), while beta diversity analysis showed distinct clustering based on geographic location (p < 0.001). Bacteroidetes were more abundant in the northern group (49.22% vs. 28.44%), while Firmicutes predominated in the southern group (59.10% vs. 32.78%). Functional prediction analysis indicated higher levels of membrane transport and lipid metabolism pathways in the southern group, suggesting differences in nutrient absorption and energy metabolism. These findings suggest that geographic location and associated environmental factors significantly influence the gut microbiota of captive ring-tailed lemurs, even under similar dietary and husbandry conditions. Our study provides insights into the impact of geographic location on gut microbiota in captive primates, highlighting the importance of considering regional factors in zoo animal management and informing future strategies for optimizing the care and conservation of captive primates across different geographic regions. Full article

The performance of large-scale photovoltaic (PV) power plants is strongly influenced by array layout parameters including module tilt angle, azimuth angle, and row spacing. These geometric variables jointly determine solar irradiance geometry, shading losses, and land-use efficiency, affecting annual energy yield and levelized cost of electricity. To achieve multi-objective comprehensive optimization of array layout parameters for a PV power generation system, a collaborative optimization strategy for PV array layout based on the lemur optimization (LO) algorithm is proposed in this paper. The method couples the Perez anisotropic irradiance model with a dynamic shading irradiance geometric model to simulate the effective insolation, incorporating land availability, shading thresholds, and maintenance access requirements. In addition, the LO algorithm is employed to solve resulting nonlinear and constrained problems, enabling an efficient global search across large parameter spaces. The case studies in Lianyungang, Dalian, and Fuzhou City show that the proposed scheme based on the LO algorithm improves annual energy yield compared with the existing optimization schemes, providing new theoretical methods and engineering application paths for the optimal layout of PV arrays. Full article

As demand for sustainable protein intensifies, edible crickets offer a promising solution to food insecurity and environmental strain, particularly in regions like Madagascar. This study investigated the effects of two rearing temperatures (28 °C and 30 °C) on life-history traits of three edible cricket species—Gryllus bimaculatus, Gryllodes sigillatus, and Teleogryllus lemur—under controlled laboratory conditions. Growth, survival, development time, and biomass yield were quantified for each species (n = 150 per temperature treatment) and analyzed using t-tests, chi-squared tests, and ANOVA. Results revealed distinct species-specific thermal responses. G. bimaculatus exhibited accelerated development and higher biomass at 30 °C without significant survival loss. G. sigillatus maintained high survival but developed more slowly at 30 °C, suggesting thermal sensitivity. In contrast, T. lemur demonstrated substantial growth gains at 30 °C but suffered a 50% reduction in survival, indicating heat intolerance. Development time and biomass yield varied significantly across species and temperature treatments (p < 0.0001). These findings highlight critical trade-offs between growth efficiency and survival in insect farming systems. G. bimaculatus emerges as a strong candidate for high-yield, thermally resilient farming, while T. lemur requires cooler rearing environments. This work informs species selection and environmental optimization for scalable, climate-adaptive cricket farming in tropical regions. Full article

The Backtracking Search Algorithm (BSA) has emerged as a promising stochastic optimization method. This paper introduces a novel hybrid evolutionary algorithm, termed LOBSA, integrating the strengths of BSA and Lemurs Optimizer (LO). The hybrid approach significantly improves global exploration and convergence speed, validated through rigorous tests on 23 benchmark functions from the CEC 2013 suite, encompassing unimodal, multimodal, and fixed dimension multimodal functions. Compared with state-of-the-art algorithms, LOBSA presents a relative improvement, achieving superior results and outperforming traditional BSA by up to 35% of global performance gain in terms of solution accuracy. Moreover, the applicability and robustness of LOBSA were demonstrated in practical constrained optimization and a fluid–structure interaction problem involving the dynamic analysis and optimization of a submerged boat propeller, demonstrating both computational efficiency and real-world applicability. Full article

Zoological environments aim to promote natural behaviours and optimal welfare conditions. Over the past decade, research on the use of artificial ultraviolet-B (UV-B) exposure has improved vitamin D₃ levels and reduced incidences of metabolic bone disease in diurnal primates; however, this has not been investigated in nocturnals. Aye-ayes (Daubentonia madagascariensis), nocturnal lemurs often housed indoors in zoos with little to no exposure to natural sunlight, have been reported to have low vitamin D₃ levels. This study aims to investigate the impacts of artificial UV-B as a supplemental healthcare strategy for aye-ayes, examining its influences on vitamin D₃ levels and positional sleeping behaviour. The 25-hydroxy-vitamin D₃ (25OHD₃) blood levels were tested before and after exposure to different levels of artificial UV-B and heat sources. Statistical analysis showed no correlation between UV-B and 25OHD₃ at group parameter levels. However, one individual showed a positive correlation. Sleeping position duration analysis showed a potential basking behaviour with the use of increased ear exposure and other thermoregulatory responses. Despite representing 8.06% of the European captive aye-aye population, these findings highlight the need for further research on vitamin D₃ parameters and responses to UV-B to optimise captive conditions and support the species’ long-term health. Full article

Global biodiversity losses continue despite intensive conservation efforts. Many mammal species are understudied due to their specialized ecological niches. One such species is the Philippine colugo (Cynocephalus volans), a nocturnal endemic species in the Philippines. In this study, we utilized Local Ecological Knowledge (LEK) to obtain baseline information on species knowledge, attitudes, population status, and threats. Between June and September 2023, we interviewed 471 residents across all villages in Anda, Bohol. The majority of local people recognized the species and had witnessed it in Anda, occasionally near households. Residents have limited knowledge of colugo diet and distribution, which they get primarily through word-of-mouth and personal experience. The species is perceived as neutral, but the willingness to conserve it is high. Although the Philippine colugo population seems to be present in several villages in Anda, one-fourth of the respondents believe it is declining. We identified hunting for consumption as the main threat to the colugo population in Anda, which, together with other threats, may corroborate this result. We recommend actively involving male farmers in colugo population monitoring and behavioral observations, as well as investigating the drivers and importance of colugo meat consumption among residents to design a proper conservation strategy. Full article

In order to protect endangered species, many zoos adopt diverse rearing models to achieve optimal conservation outcomes. This study employed metagenomic approaches to assess differences in the fecal microbiome of captive and semi-free-ranging ring-tailed lemurs (Lemur catta). The results show that captivity significantly altered the microbial community structure. The inter-individual variability in the microbial community within the captive-bred (CB) group was lower than that in the semi-free-ranging (FR) group, yet these individuals harbored a higher abundance of potential pathogens (Treponema_D). In contrast, microbial genera associated with fiber degradation and short-chain fatty acid production in the FR group were significantly elevated (Faecalibacterium, Roseburia, and Megamonas) as compared to the CB group. Environmental variations between the two rearing systems led to distinct profiles in microbial functions and carbohydrate-active enzyme gene composition. Notably, the FR group of lemurs exhibited an increased abundance of enzyme genes associated with the degradation of complex polysaccharides (cellulose, hemicellulose, and pectin), suggesting that their diet, rich in natural plant fibers, enhances the capacity of their gut microbiota to extract essential energy and nutrients. Conversely, the CB group displayed a more homogeneous microbial community with a higher prevalence of potential pathogens, implying that a captive lifestyle may negatively impact gastrointestinal health. These findings offer valuable insights into the influence of rearing conditions on gut microbial ecology and its potential implications for the health management of ring-tailed lemurs. Full article

Enzymes of the cytochrome P450 monooxygenase family 4 (CYP4) in mammals are generally involved either in endobiotic metabolism (e.g., acting on fatty acids or eicosanoids), or the modification of xenobiotics including therapeutic drugs. CYP4B1 is special, as it is an enigmatic enzyme acting at the interface between xenobiotic and endobiotic metabolism. However, a systematic analysis of CYP4B1’s substrate scope has not yet been reported. Herein, a three-step approach to identify novel substrates for three CYP4B1 orthologs (namely from rabbits, green monkeys, and mouse lemurs) is described. First, screening of a library containing 502 natural products revealed potential novel substrate groups for CYP4B1. Second, based on these results, a systematic library was defined consisting of 63 compounds representing 10 compound groups. Third, in vitro conversion of these compounds by CYP4B1 and identification of conversion products were conducted, supported by in silico docking, allowing the prediction of binding probabilities and potential oxidation sites. We report five new substrate groups (acyclic, monocyclic and bicyclic terpenoids, stilbenoids, and vanilloids), twenty-eight new substrates (inter alia capsaicin, gingerol, genistein, stilbene, myristicin, thioanisole), and two new reaction types for CYP4B1 (S-oxidation, O-demethylation). Consequently, CYP4B1 is a far more promiscuous enzyme than previously thought. Full article

The sublingua is an anatomical structure located under the tongue. This rare organ can be present in some animals as a rudimentary structure, but among prosimian primates, such as lemurs and lorises, it is fully developed. In addition to the sublingua, prosimians have modified lower incisors and canines called “dental comb”. The anatomy of sublingua has been studied macro and microanatomically since the early 19th century. Most authors argue that the sublingua is an oral morphological adaptation to develop a toothbrush’s role in cleaning the dental comb. However, others assert that the functional role has yet to be established. Comparative studies of macro and microanatomy are scarce or incomplete for primates; thus, the putative function remains unclear. To better understand the functional significance of the sublingua, we studied this structure in Lemur catta and Varecia variegata specimens using histochemical staining techniques and scanning electron microscopy with microanalysis. The new data obtained provide a fuller picture of the role assigned to sublingua so far, which could be more complex. In light of the morphological findings, we should consider additional roles/functions of the sublingua, including but not limited to food processing, grooming or social behavior. Full article