Environmental Changes Research Articles

Variability in Heating Demand Predictions: A Comparative Study of PHPP and Mc001-2022 in Existing Residential Buildings

The construction industry is a key driver of environmental change due to its extensive use of resources and high emissions, thus significantly burdening global efforts towards sustainable development targets. A large portion of the environmental footprint of buildings results from the energy required to sustain indoor comfort levels. Thus, enhancing the energy efficiency of existing buildings becomes critical in reducing their environmental impact. This study explores the impact of thermal performance improvements on the heating demand, employing numerical modeling and two energy performance methodologies, PHPP and Mc001-2022, across various climatic datasets and case studies in Romania. The results show substantial variability in heating demand predictions: Mc001-2022 predicts up to 27.2% higher continuous heating demands and 21.0% higher intermittent demands compared to PHPP in one case study. In the second case study, the differences range from 8.1% higher to 6.9% lower for continuous heating and from 3.3% higher to 9.9% lower for intermittent heating, depending on the scenario. These findings underscore the importance of the methodological choice and localized climatic data in heating demand assessments, highlighting the need for a tailored, context-specific approach to energy performance assessment, integrating multiple energy efficiency measures suited to the unique characteristics of each building.

The Range‐Wide Genetic Structure of a High‐Elevation Conifer Species, Subalpine Larch

ABSTRACTAimSubalpine larch is a long‐lived conifer with a restricted distribution at treeline in the mountains of western North America. Climate change is reducing the availability of this habitat and subalpine larch is unlikely to adapt to its changing environment due to its long generation time, relatively low levels of standing genetic variation and the high degree of habitat fragmentation across the species' range. This study seeks to elucidate the genetic structure of subalpine larch to inform future conservation and management efforts.LocationWestern North America.TaxonSubalpine larch (Larix lyallii Parl.).MethodsTissue was collected from high‐elevation populations across the entire species range. Restriction site associated DNA sequencing was used to generate single nucleotide polymorphism (SNP) data. Population genetic analyses identified genetic differentiation.ResultsClustering analyses performed using 751 neutral SNPs identified three genetically differentiated regions: the Cascade Range, the southern Rocky Mountains and the northern Rocky Mountains. AMOVA confirmed significant genetic differentiation among regions. A discriminant analysis of principal components and a dendrogram of Provesti's genetic distance both supported the hypothesis that genetically distinct lineages arose after dispersal from a single Pleistocene refugium. Significant isolation by distance (IBD) supported the key role of dispersal in shaping modern patterns of genetic variation in subalpine larch.Main ConclusionsPost‐Pleistocene dispersal resulted in genetic differentiation among groups of subalpine larch in the Cascade Range, the southern Rocky Mountains and the northern Rocky Mountains. These three regions should be prioritised for future management.

Unveiling the role of epigenetics in leaf senescence: a comparative study to identify different epigenetic regulations of senescence types in barley leaves

BackgroundDevelopmental leaf senescence (DLS) is an irreversible process followed by cell death. Dark-induced leaf senescence (DILS) is a reversible process that allows adaptations to changing environmental conditions. As a result of exposure to adverse environmental changes, plants have developed mechanisms that enable them to survive. One of these is the redirection of metabolism into the senescence pathway. The plant seeks to optimise resource allocation. Our research aims to demonstrate how epigenetic machinery regulates leaf senescence, including its irreversibility.ResultsIn silico analyses allowed the complex identification and characterisation of 117 genes involved in epigenetic processes in barley. These genes include those responsible for DNA methylation, post-translational histone modifications, and ATP-dependent chromatin remodelling complexes. We then performed RNAseq analysis after DILS and DLS to evaluate their expression in senescence-dependent leaf metabolism. Principal component analysis revealed that evaluated gene expression in developmental senescence was similar to controls, while induced senescence displayed a distinct profile. Western blot experiments revealed that senescence engages senescence-specific histone modification. During DILS and DLS, the methylation of histone proteins H3K4me3 and H3K9me2 increased. H3K9ac acetylation levels significantly decreased during DILS and remained unchanged during DLS.ConclusionsThe study identified different epigenetic regulations of senescence types in barley leaves. These findings are valuable for exploring epigenetic regulation of senescence-related molecular mechanisms, particularly in response to premature, induced leaf senescence. Based on the results, we suggest the presence of an epigenetically regulated molecular switch between cell survival and cell death in DILS, highlighting an epigenetically driven cell survival metabolic response.

Circadian regulatory networks of glucose homeostasis and its disruption as a potential cause of under-nutrition.

The circadian clock system, an evolutionarily conserved mechanism, orchestrates diurnal rhythms in biological activities such as behavior and metabolism, aligning them with the earth's 24-hour light/dark cycle. This synchronization enables organisms to anticipate and adapt to predictable environmental changes, including nutrient availability. However, modern lifestyles characterized by irregular eating and sleeping habits disrupt this synchrony, leading to metabolic disorders such as obesity and metabolic syndrome, evidenced by higher obesity rates among shift workers. Conversely, circadian disturbances are also associated with reduced nutrient absorption and an increased risk of malnutrition in populations such as the critically ill or the elderly. The precise mechanisms of these disturbances in leading to either over-nutrition or under-nutrition is complex and not yet fully understood. Glucose, a crucial energy source, is closely linked to obesity when consumed excessively and to weight loss when intake is reduced, which suggests that circadian regulation of glucose metabolism is a key factor connecting circadian disturbances with nutritional outcomes. In this review, we describe how the biological clock in various tissues regulates glucose metabolism, with a primary focus on studies utilizing animal models. Additionally, we highlight current clinical evidence supporting the association between circadian disturbance and glucose metabolism, arguing that such disruption could predominantly contribute to under-nutrition due to impaired efficient utilization of nutrients.

Strathalan Cave revisited: Stone Age networks and environments at the foot of the Drakensberg, South Africa

The broader Drakensberg is an important region for understanding population dynamics and adaptation between the Late Pleistocene and Holocene. Here, we announce our campaign to re-excavate Strathalan Cave in the northeastern Cape of South Africa. Strathalan Cave sits at the foothills of the uKhahlamba-Drakensberg at the edge of the Great Escarpment of southern Africa. Well-known for its organic preservation, the site is important for understanding the archaeology of the region. People have occupied Strathalan Cave intermittently from ca. 29 000 years ago (ka), so exploring occupational patterns at sites such as these is a valuable means of understanding Stone Age behaviour during glacial Marine Isotope Stage 2 (ca. 29-14 ka). In this paper, we provide the first detailed description of the geological, geomorphological, sedimentary and environmental context of Strathalan Cave and review previous studies conducted on the site and region. We also introduce the goals of our re-excavation project and present a detailed map of the three cavities that make up the Strathalan Cave complex as part of a new, comprehensive, spatial control system established on site. Given the remarkable preservation of organic materials, Strathalan Cave may provide an important and rare source of archaeological and palaeoenvironmental data for this period. Future work at Strathalan will likely contribute to our understanding of the links between settlement patterns and environmental change. This is especially important given that Strathalan sits at the juncture between different environmental and geographic regions.

Toxic effects of ZnO NPs on immune response and tissue pathology in Mytilus galloprovincialis

Nano-zinc oxide (ZnO NPs), as widely used nanomaterials, are inevitably released into aquatic environments, posing potential threats to aquatic organisms. Mytilus galloprovincialis is a bivalve species sensitive to changes in marine ecological environments, but there has been limited research on its toxicity response to ZnO NPs. Therefore, we selected M. galloprovincialis as the research subject and exposed them to 50 µg/L ZnO NPs for 96 h and 30 days to determine the dissolution of ZnO NPs in seawater and their distribution in M. galloprovincialis. The toxicity of ZnO NPs in M. galloprovincialis was then evaluated through gene expression, tissue pathology, and cellular immune response. The results showed that ZnO NPs could enrich Zn in various tissues of the mussel, in the order of gills > hepatopancreas > adductor muscle > mantle. Seven immune-related genes including four heat shock protein genes (HSPA12A, sHSP24.1, sHSP22, TCTP) and three apoptotic genes (Ras, p63 and Bcl-2) were altered to varying degrees. There was a downward trend in lysosomal membrane stability of M. galloprovincialis after exposure to ZnO NPs for 96 h and 30 days, while ROS and apoptosis rates increased significantly. Furthermore, the seven genes, apoptosis, LMS, and ROS were dependent on exposure time, treatment, and their interaction. Histopathological damage included disorganisation of hepatopancreas epithelial cells, gill filament swelling, and contraction of blood sinuses. These results indicated that ZnO NPs exerted toxicity in M. galloprovincialis, affecting the immune system, resulting in changes in the expression of immune-related genes and ultimately leading to histopathological changes. Our research findings could contribute to systematically understand the impact of ZnO NPs on bivalves in aquatic environments and provide a theoretical basis for marine pollution assessment.

Multicellularity and increasing Reynolds number impact on the evolutionary shift in flash-induced ciliary response in Volvocales

BackgroundVolvocales in green algae have evolved by multicellularity of Chlamydomonas-like unicellular ancestor. Those with various cell numbers exist, such as unicellular Chlamydomonas, four-celled Tetrabaena, and Volvox species with different cell numbers (~1,000, ~5,000, and ~10,000). Each cell of these organisms shares two cilia and an eyespot, which are used for swimming and photosensing. They are all freshwater microalgae but inhabit different fluid environments: unicellular species live in low Reynolds-number (Re) environments where viscous forces dominate, whereas multicellular species live in relatively higher Re where inertial forces become non-negligible. Despite significant changes in the physical environment, during the evolution of multicellularity, they maintained photobehaviors (i.e., photoshock and phototactic responses), which allows them to survive under changing light conditions.ResultsIn this study, we utilized high-speed imaging to observe flash-induced changes in the ciliary beating manner of 27 Volvocales strains. We classified flash-induced ciliary responses in Volvocales into four patterns: “1: temporal waveform conversion”, “2: no obvious response”, “3: pause in ciliary beating”, and “4: temporal changes in ciliary beating directions”. We found that which species exhibit which pattern depends on Re, which is associated with the individual size of each species rather than phylogenetic relationships.ConclusionsThese results suggest that only organisms that acquired different patterns of ciliary responses survived the evolutionary transition to multicellularity with a greater number of cells while maintaining photobehaviors. This study highlights the significance of the Re as a selection pressure in evolution and offers insights for designing propulsion systems in biomimetic micromachines.

Clinical signs and post-mortem lesions caused by clostridial enterotoxemia in rabbits

Enterotoxemia, accompanied by diarrhea and bloating, is still a matter of pressing concern to the rabbit farming. Clostridia bacteria are often isolated from the internal organs of rabbits that have died of an anaerobic infection. Clostridial infection, manifested in various forms, is a major problem for veterinarians. The following drivers contribute to the emergence of the infectious disease: malnutrition (insufficient fiber intake); non-compliance with hygiene requirements for animal handling; unsustainable use of antibacterial drugs; gastrointestinal congestion. All these drivers can disrupt healthy caecum microflora due to changes in the gastrointestinal environment. Low-fiber diets result in slow cecum motility, thus, delaying transit of the intestinal contents and eventually changing the microflora. Use of antibiotics together with stress make Clostridia accumulate in the gastrointestinal tract, at the same time, reducing the number of microorganisms of other groups. The first signs of toxicoinfection are observed when rabbit kits are weaned from does. Clinical manifestation begins with bloating, weakness, inappetence, which ultimately lead to death. Observations have shown that the risk group includes rabbit kits weaned from the 35–77-day old does. Mortality was less reported in breeding stock and among replacement young animals. Autopsy revealed signs of enterotoxemia: serous-catarrhal gastritis, serous-hemorrhagic lymphonodulitis, degenerated kidneys, liver and heart muscle; passive congestion of lungs and pulmonary edema. Microbiological diagnosis revealed Clostridium histolyticum and Clostridium perfringens species known for their pronounced toxigenic profile, most often bacteria were found in the stomach, intestines and heart.

Preclinical Development of a Novel Zika Virus-like Particle Vaccine in Combination with Tetravalent Dengue Virus-like Particle Vaccines

Declared as a Public Health Emergency in 2016 by the World Health Organization (WHO), the Zika virus (ZIKV) continues to cause outbreaks that are linked to increased neurological complications. Transmitted mainly by Aedes mosquitoes, the virus is spread mostly amongst several tropical regions with the potential of territorial expansion due to environmental and ecological changes. The ZIKV envelope protein’s domain III, crucial for vaccine development due to its role in receptor binding and neutralizing antibody targeting, was integrated into sterically optimized AP205 VLPs to create an EDIII-based VLP vaccine. To increase the potential size of domains that can be accommodated by AP205, two AP205 monomers were fused into a dimer, resulting in 90 rather than 180 N-/C- termini amenable for fusion. EDIII displayed on AP205 VLPs has several immunological advantages, like a repetitive surface, a size of 20–200 nm (another PASP), and packaged bacterial RNA as adjuvants (a natural toll-like receptor 7/8 ligand). In this study, we evaluated a novel vaccine candidate for safety and immunogenicity in mice, demonstrating its ability to induce high-affinity, ZIKV-neutralizing antibodies without significant disease-enhancing properties. Due to the close genetical and structural characteristics, the same mosquito vectors, and the same ecological niche of the dengue virus and Zika virus, a vaccine covering all four Dengue viruses (DENV) serotypes as well as ZIKV would be of significant interest. We co-formulated the ZIKV vaccine with recently developed DENV vaccines based on the same AP205 VLP platform and tested the vaccine mix in a murine model. This combinatory vaccine effectively induced a strong humoral immune response and neutralized all five targeted viruses after two doses, with no significant antibody-dependent enhancement (ADE) observed. Overall, these findings highlight the potential of the AP205 VLP-based combinatory vaccine as a promising approach for providing broad protection against DENV and ZIKV infections. Further investigations and preclinical studies are required to advance this vaccine candidate toward potential use in human populations.

Exploring sustainable food system transformation options in China: An integrated environmental-economic modelling approach based on the applied general equilibrium framework

Our food system drives global environmental change, and differences in environmental concerns of consumers may cause negative environmental ‘spillover effects’ in less concerned countries. While food system transformation is increasingly recognised as crucial for mitigating such negative environmental spillovers, possible unintended negative environmental consequences in other regions and/or economic sectors have received less attention. Using an integrated environmental-economic modelling framework and scenario analyses, we explored options for more sustainable food systems and to mitigate the negative environmental spillovers from trading partners to China. We found that doubling novel soy-based food (soy-based meat) consumption while reducing pork consumption in China decreased Chinese economy-wide emissions of greenhouse gases (GHGs) by 1 % and acidification pollutants by 3 %. However, it increased Chinese economy-wide emissions of eutrophication pollutants by 2 %, driven by the increased production of soy-based food and other food with relatively high emission intensities of eutrophication pollutants. Combining a dietary shift with the adoption of cleaner cereals production technology for half of the current resources used for cereals production decreased Chinese economy-wide emissions of GHGs by 1 %, acidification pollutants by 7 %, and eutrophication pollutants by 3 %, but required capital reallocation from other sectors. Implementing a unilateral environmental policy in China (i.e., implementing incentive-based emission permits to reduce emissions of all pollutants by 3 % annually) increased economy-wide emissions of GHGs in trading partners by 2 %. This ‘carbon leakage’ emerges due to the shift of production of products with relatively high emission intensities (i.e., nitrogen fertiliser and livestock) from China to its trading partners through international trade. We demonstrate that indirect environmental impacts are crucial to consider when analysing the economy-wide consequences of food system transformations, as these indirect impacts may inadvertently affect other regions and/or economic sectors that were not initially targeted. Our study offers policymakers insights into designing effective policies for more sustainable food systems and sheds light on trade-offs among competing environmental and economic goals.

The effect of nitrosative stress on histone H3 and H4 acetylation in Phytophthora infestans life cycle

The oomycete Phytophthora infestans is one of the most destructive phytopathogens globally. It has a proven ability to adapt to changing environments rapidly; however, molecular mechanisms responsible for host invasion and adaptation to new environmental conditions still need to be explored. The study aims to understand the epigenetic mechanisms exploited by P. infestans in response to nitrosative stress conditions created by the (micro)environment and the host plant. To characterize reactive nitrogen species (RNS)-dependent acetylation profiles in avirulent/virulent (avr/vr) P. infestans, a transient gene expression, ChIP and immunoblot analyses, and nitric oxide (NO) emission by chemiluminescence were used in combination with the pharmacological approach. Nitrosative stress increased total H3/H4 acetylation and some histone acetylation marks, mainly in sporulating hyphae of diverse (avr/vr) isolates and during potato colonization. These results correlated with transcriptional up-regulation of acetyltransferases PifHAC3 and PifHAM1, catalyzing H3K56 and H4K16 acetylation, respectively. NO or peroxynitrite–mediated changes were also associated with H3K56 and H4K16 mark deposition on the critical pathogenicity-related gene promoters (CesA1, CesA2, CesA3, sPLD-like1, Hmp1, and Avr3a) elevating their expression. Our study highlights RNS-dependent transcriptional reprogramming via histone acetylation of essential gene expression in the sporulating and biotrophic phases of plant colonization by P. infestans as a tool promoting its evolutionary plasticity.

The Nexus between Environmental Factors and Behaviour Change in the Upper East Region of Ghana: The Mediating Role of Marketing Strategies

This study aimed to explore the mediating role of marketing strategies in the relationship between environmental factors and behavior change in healthcare utilisation. A cross-sectional survey design was conducted using a random sampling technique to select 474 healthcare workers from six Health Directorates across Municipalities and Districts in the Upper East Region of Ghana. The target population from which the sample size was determined was 1980. The theories that guided this study were the Health Belief Model and the Theory of Planned Planned Behaviour. A structured questionnaire was designed using a five-point Likert scale and administered to the respondents. The data was collected over three months from February to April. A Structural Equation Model (SEM) with AMOS was employed to analyse the data. Findings revealed that marketing strategies mediate the relationship between environmental factors and behaviour change. The predicted hypotheses were found to be positive and significant. The study highlights the importance of marketing strategies in disseminating health-related information, which influences positive behaviour change toward healthcare utilisation. The study found that marketing strategies play a crucial role in disseminating health information and promoting behaviour change. The mediating role of marketing strategies in the relationship between environmental factors and behaviour change was established. All hypotheses were confirmed, demonstrating the key role of marketing strategies in improving health outcomes through behaviour modification. It is recommended that healthcare facility managers consider incorporating marketing strategies into their strategic plans to optimise outcomes.

Ultrastructural study of pollen and tapetum development in Hydrocleys nymphoides, Alisma plantago-aquatica, and Sagittaria montevidensis (Alismataceae).

The Alismataceae family, widely distributed across tropical temperate swamps and wetlands, includes 15 genera post-merger with Limnocharitaceae. In Argentina, six genera are represented across three clades. Embryological characters, notably the male gametophyte and anther, are crucial in taxonomy due to their stability against environmental changes. This study aims to analyze the ultrastructure of the tapetum and pollen grain development in three economically and ecologically important species representing each clade: Sagittaria montevidensis (Clade A), Hydrocleys nymphoides (Clade B), and Alisma plantago-aquatica (Clade C). Anthers at different developmental stages were processed according to classic techniques for their observation with bright-field and transmission electron microscopy. The three studied species within the Alismataceae family exhibit similar reproductive characteristics. Seven stages of pollen grain development were identified. The microsporogenesis is successive with a regular meiosis. The ultrastructure of the tapetal cells shows similarities to other species with plasmodial tapetum. During the microspore tetrad stage, there is tapetal hyperactivity and an increase in secretion processes. In the free microspore stage, the tapetal cells lose their walls and increase the amount of rough endoplasmic reticulum forming a network of cisternae that extend into evaginations. Later cells completely invade the anther locule and fuse to form a tapetal plasmodium. No peritapetal membrane with orbicules was observed. Pollen is released at the tricellular stage. The pollen grain wall presents an ectexine with a basal layer, columellae, and tectum with supratectal spines while an endexine is not observed in any of the three species. This research enhances the understanding of tapetal cell interactions with developing pollen grains and contributes to the knowledge of the ultrastructure of plasmodial tapetum. Moreover, these findings highlight evolutionary reproductive patterns in Alismataceae, suggesting the plasmodial tapetum as a synapomorphy for the order.

Montane peatland response to drought: Evidence from multispectral and thermal UAS monitoring

This paper investigates the response of mid-latitude montane peatlands to climate warming, focusing on changes occurring in a montane peat bog during a drought period. Unmanned Aerial Systems (UAS) equipped with multispectral and thermal sensors were used for high-resolution monitoring to analyze qualitative changes within the peat bog and their spatial distribution. The study was conducted in the Rokytka mountain peat bog in Šumava National Park, Czech Republic, which is one of the largest mountain peat bog complexes in Central Europe. Monitoring took place during the 2019 vegetation season, coinciding with the peak of the 2015–2019 drought. The recurrent UAS imaging campaigns were complemented by continuous hydrological and hydropedological monitoring and in-situ calibration measurements. The findings revealed diverging responses of montane peatlands to climate change across different functional zones of the peat bog. UAS thermal mapping identified distinct land surface temperature variations across various vegetation categories under different conditions. Notably, ponds and waterlogged areas displayed a stabilizing effect on land surface temperature variability, though they exhibited different absolute temperatures. In contrast, shallow waterlogged areas exhibited surface temperatures akin to dry open peat areas. Multispectral UAS monitoring demonstrated significant transitions among the peat bog zones in response to heat and drought propagation. The most pronounced changes occurred in shallow waterlogged areas, which shrank notably from 22.8% to 4.5%, while bare peat expanded from 26.8% to 45.5% during the 2019 drought season. High-resolution thermal and multispectral monitoring has revealed the scope and magnitude of the intra-peatland responses to drought and heat waves and serves as a sensible indicator of environmental changes of peatlands. It has disclosed a large cumulative effect of change in an environment composed of highly heterogeneous and subtle structures. The results highlighted the effectiveness of UAS monitoring in understanding the extent of change in montane peatlands as a fragile environment exposed to the effects of climate change.

Plasmonic coupling dependent sensitivity in localized surface plasmon resonance based optical sensors

This paper investigates the impact of environmental changes on silver nanoparticles (AgNp) immobilized sensor probe within strong and weak plasmonic coupling regimes. To monitor these interaction regimes, evanescent wave absorption based on fiber optic and attenuated total reflection techniques have been employed. In the weak coupling regime, variations in refractive index (RI) primarily affect intensity rather than wavelength. Conversely, in the strong coupling regime, intensity decreases, while wavelength sensitivity increases with changes in RI. Our findings qualitatively agree with a theoretical framework based on the discrete dipole approximation (DDA) for two-particle interacting systems, providing valuable insights for optimizing plasmonic interactions to enhance sensitivity. This information will aid the scientific and industrial community in understanding the plasmonic interaction region for maximizing sensitivity of Localized surface plasmon resonance (LSPR) based photonic devices.

228 Evaluation of sire vs. dam influences on age at first parturition in Brahman heifers

Abstract The objective of this study was to determine if sire or dam had a stronger impact on age at first parturition of Brahman heifers (n = 833) born between 2000-2021. Typically, in Bos taurus heifers, puberty occurs between 10 to 12 mo of age leading to parturition of the first calf occurring around 24 mo of age. However, in Bos indicus cattle, puberty is achieved between 15 to 17 mo of age leading to a first calf around 36 mo of age. The ability of heifers to achieve pubertal status earlier plays a vital role in reproductive success. For selection purposes, knowing if early pubertal attainment is influenced more by the sire or dam is important for herd management. For this study, to minimize any epigenetic and environmental changes, all heifers originated and were developed at the Texas A&M AgriLife Research Center at Overton. Sire groups (SG) and dam groups (DG) were established based on the number of offspring used in the study. Sire groups were comprised of SG-1 (1+ calves sired; n = 58 sires), SG-2 (5+ calves sired; n = 44 sires), SG-3 (10+ calves sired; n = 31 sires), SG-4 (15+ calves sired; n = 23 sires), SG-5 (20+ calves sired; n = 17 sires), and SG-6 (25+ calves sired; n = 12 sires). Dam groups consisted of DG-1 (1+ calves; n = 489 dams), DG-2 (2+ calves; n = 215 dams), DG-3 (3+ calves; n = 81 dams), DG-4 (4+ calves; n = 38 dams), and DG-5 (5+ calves; n = 9 dams). Statistical analysis (PROC GLM; SAS 9.4) included the fixed effect of sire group (dam group) and all dams (sires) utilized in that grouping. Significance for age at first calving was considered at P < 0.05. Mean separation for age was performed using LSmeans. Sire significantly impacted age at first calving in SG-1 (P = 0.0173) vs dam effect (P = 0.3993; n = 489 dams), SG-2 (P = 0.0159) vs dam effect (P = 0.5476; n = 481 dams), SG-3 (P = 0.0023) vs dam effect (P = 0.2532; n = 439 dams), SG-4 (P = 0.0022) vs dam effect (P = 0.3997; n = 400 dams), SG-5 (P = 0.0002) vs dam effect (P = 0.0602; n = 361 dams), and SG-6 (P = 0.0005) vs dam effect (P = 0.1058; n = 305 dams). The dam impact on age at first calving was never significant in the dam groupings but sires did impact age at first calving in two groups: DG-1 (P = 0.3993) vs sire effect (P = 0.0173; n = 58 sires), DG-2 (P = 0.4823) vs sire effect (P = 0.0173; n = 56 sires), DG-3 (P = 0.3011) vs sire effect (P = 0.3420; n = 49 sires), DG-4 (P = 0.3911) vs sire effect (P = 0.6278; n = 40 sires), and DG-5 (P = 0.3042) vs sire effect (P = 0.9159; n = 23 sires). In summary, evaluation of sire and dam influences on age at first parturition for female offspring demonstrates that the ability to calve at an earlier age is influenced by the sire but not the dam. Further studies into the mechanisms for the transmission of this trait are warranted.

184 Effects of cattle hide color and changing environmental conditions at northern latitudes on feeder cattle performance and behavior

Abstract While suitable research has been done on the influence of climatic conditions on feeder cattle welfare, we have seen limited work done that assesses the relationship of hide color and cattle thermoregulation in response to extreme environmental changes, particularly of those seen at northern latitudes. Specifically, there is limited research on the effects of environmental stressors and cattle hide color on performance and intake. Therefore, the objective of this study is to evaluate feeder cattle performance in response to environmental conditions and hide color. Angus-based yearling steers [n = 40; average body weight (BW) = 409.28 kg were stratified by BW and hide color (red, white, and black) and were randomized into 10 pens at the Northern Agricultural Research Center in Havre, MT. Steers were on trial from 20 February 2023 to 11 July 2023 (141 d) and fitted with an electronic ear tag and adapted to the Vytelle system (Vytelle, Lenexa, KS) for 14 d prior to the start of the study. All 10 pens consisted of two electronic feed bunks equipped with an antenna to detect animal presence, load cells to measure feed disappearance and wireless transfer to a data-acquisition computer. Finishing diet (8.6% CP, 75% TDN) consisted of 69% corn, 21% corn silage, 10% wheat straw, and 0.45 kgּ animal-1ּ d-1 of beef grower pellet with a fortified mineral and vitamin package. Initial and final unshrunk BW were obtained on two consecutive days and averaged. Every 28 d during the experiment, steers were weighed prior to feeding and a measurement of coat depth was taken. Animal surface temperature was recorded via a FLIR E5xt thermal imaging camera on the same day of every week at 0730 h (prior to feeding) and 1330 h (6 h post feeding), for 20 wk. There was no difference in hair depth between the white hided steers and other treatments (P ≥ 0.26). However, there was a treatment effect (P = 0.01) of hide color on cattle surface temperature, with black and red hided steers averaging 2.85°C greater than white hided steers. There was no effect of treatment on average daily gain (P = 0.55) averaging 1.34 kg/d. Additionally, there was no treatment effect on average daily intake (P = 0.36), averaging 10.76 kg per day. There was a treatment effect on gain to feed efficiency (P = 0.05); however, post hoc means separation analysis showed no difference between treatments. In summary, although there were treatment effects on animal surface temperature, they were not reflected in animal performance.

Research on aquatic biological signal recognition based on mode decomposition and deep learning

Abstract As an important research content in the field of marine biology and ecology, aquatic biological signal (ABS) recognition is of great significance for understanding marine ecosystems, protecting biodiversity, and monitoring environmental changes. To improve the recognition accuracy of ABS, this paper proposes a new ABS recognition method based on mode decomposition and deep learning. First, real ABS data were obtained from the public website, and some data were selected for the simulation experiment. Secondly, the signal is decomposed using improved variational mode decomposition by human evolutionary optimization algorithm (HEOA-VMD), and the decomposed intrinsic mode function (IMF) set is classified into low complexity and high complexity IMF using improved Lempel-Ziv complexity (ILZC) and reverse permutation entropy (RPE). Then, mutual information (MI) is used to select double eigenvectors from low and high complexity IMF, respectively, and recognition is performed based on the double eigenvectors using weighted-convolutional neural network (CNN)-bidirectional gate recurrent unit (BIGRU)-Attention model. Finally, the proposed ABS recognition method is applied to both chaotic and real signals, and additional proof of universality is performed using real signals. The result of the study shows that the accuracy of the proposed method for the recognition of chaotic and real signals is as high as 97.3% and 98.0%. In conclusion, the research on ABS recognition in this paper is successful and has a broad application prospect.

Juvenile responses to immune challenges are not carried through to subsequent life stages in an insect

Environmental variability can significantly impact individual survival and reproduction. Meanwhile, high population densities can lead to resource scarcity and increased exposure to parasites and pathogens. Studies with insects can offer valuable insights into eco-immunology, allowing us to explore the connections between these variables. Here we use the moth Anticarsia gemmatalis to examine how increases in population density and immunological challenge during the larval stage shape its investment in immune defence and reproduction. Larvae reared at a high population density exhibited greater lytic activity against bacteria compared to those reared at low density, whilst bacterial challenge (i.e. bacteria-immersed needles) also increased lytic activity. There was no interaction between the variables population density and bacterial challenge, indicating that these are independent. Surprisingly, neither increase in lytic activity carried through to activity in prepupal haemolymph. Rearing of larvae at a high density delayed pupation and decreased pupal weight. The immunological stimulus did not significantly influence pupal development. Lower population density as a larva resulted in greater adult weight, but did not significantly influence lytic activity in the eggs or the number of eggs laid. Negative correlations were found between lytic activity in the eggs and the number of eggs, as well as between adult weight and the number of eggs. Overall, this study demonstrates that high population density and immune challenge trigger increased lytic activity in caterpillars, but this effect is transient, not persisting into later stages. The trade-offs observed, such as delayed pupation and reduced prepupal weights under high density, suggest a balancing act between immune investment and developmental aspects. The findings hint at a short-term adaptive response rather than a sustained strategy. The implications of delayed pupation and smaller adult moths could influence the moth's life history strategy, impacting its role in the ecosystem. Further research tracking larval immune investment and subsequent reproductive success will unveil the evolutionary dynamics of this relationship in changing environments.

147 The ‘horse-side’ of host-microbe interactions and gastrointestinal homeostasis in the equine hindgut

Abstract Homeostasis is a complex physiological process that enables biological systems to maintain balanced internal environments in response to internal and external stimuli. In the equine gastrointestinal (GI) tract, homeostasis involves a network of factors that regulate gene expression, maintain the integrity of the mucosal barrier, and modulate immune responses to pathogenic microorganisms while supporting commensal bacteria that provide benefits to the host (Figure 1). These factors work together and respond to changes in diet, environment, external stress, and challenges by infectious agents or toxins. Proper gastrointestinal function is dependent on maintaining homeostasis in the system, and the dynamic interactions between the microbial population (the microbiota) and the equine host are central to this equilibrium. The regulation and interplay between the equine host and GI microbiota are evident in the distribution of distinct microbial communities within the various compartments of the equine hindgut. The contributions of each compartment to digestive physiology and the overlap with various stages of microbial fermentation in the equine hindgut are well-researched. What remains to be documented is gene expression in tissues of the equine GI and the underlying role this might play in the processes of digestion, physiology, and homeostasis in the GI. To better understand the roles that host gene expression plays in the interactions with the microbiota, it is critical that we investigate gene expression in the different tissues along the intestinal tract. Protein-coding genes are crucial in maintaining the health of the gastrointestinal tract. They direct the synthesis of various structural elements, molecular transporters, and digestive enzymes, which support digestion, nutrient absorption, and gut integrity. Non-coding genes also play an important role in regulating protein-coding gene expression, modulating immune responses, and maintaining gut barrier function. Moreover, there is evidence that non-coding transcripts regulate the composition of microbial communities in the GI tract. The presentation will focus on the current research and future directions for investigating protein-coding and non-coding gene expression to understand the mechanisms involved in the host-microbe interaction in the equine hindgut and their potential role in maintaining GI homeostasis.