Search Results (286)

Mountain biking over rough terrain exposes riders to vibrations that may affect comfort, health, bicycle control, and performance. This study analyzed the effect of wheel diameter on vibration transmission and performance during a short uphill and downhill test over rocky terrain. Forty-nine highly trained male mountain bikers completed repeated trials using two equivalent hardtail mountain bikes with 26- and 29-inch wheels. Vibrations were recorded with eight triaxial accelerometers placed on the bicycle and rider, and performance was assessed using an electronic photocell timing system. Both wheel sizes showed a similar vibration pattern, with lower root mean square (RMS) acceleration values at the helmet and coccyx and higher values at the wrists and ankles. However, wheel diameter significantly influenced vibration transmission. During the uphill test, the 26-inch bicycle produced higher accelerations at the coccyx and rear hub, whereas during the downhill test, the 29-inch bicycle transmitted greater vibrations to the rider’s wrists and ankles. No significant differences were observed between wheel sizes in the time required to complete either the uphill or downhill tests. These findings suggest that, in short and highly irregular uphill and downhill sections, 29-inch wheels do not necessarily improve performance over 26-inch wheels, although they modify the distribution of vibrations transmitted to the rider. Full article

We conducted an online cross-sectional study to assess malnutrition risk, food and nutrition insecurity, and perceived barriers and facilitators to dietary management among adults (18–64 years old) with a self-reported clinical diagnosis of inflammatory bowel disease (IBD) in outpatient and community settings. We assessed malnutrition risk using the Saskatchewan IBD-Nutrition Risk screening tool, food security risk using the two-item Hunger Vital Signs questionnaire, and nutrition security risk using a validated four-item tool. Open-ended questions elucidated barriers and facilitators to dietary management of IBD. Among 57 participants who self-reported a clinical diagnosis of IBD, 52.6% (n = 30/57) had ulcerative colitis, and 47.4% (n = 27/57) had Crohn’s disease. Nutrition insecurity was higher among those at high risk of malnutrition than among those at low-to-medium risk (p = 0.018), and there were no differences in food security status (p = 0.081). Using univariate logistic regression, the odds of being classified as having a high risk of malnutrition were associated with being male, following a special diet or nutrition plan, experiencing IBD-related flare-ups, and nutrition insecurity. Furthermore, healthcare professionals and social support, as well as digital resources/nutrition-related apps, were identified as facilitators to dietary management, while barriers included food access and expense, limited nutrition knowledge and resources, and fear of IBD-related symptom flare-ups. Although self-reported malnutrition risk and food and nutrition insecurity are common, larger prospective studies incorporating validated disease-activity measures and comprehensive nutritional assessment are needed to clarify these relationships and evaluate integrated dietetic and social-support interventions. Full article

The present study describes a rare and extreme case of prolonged survival in domestic sheep (Ovis aries) under severe natural conditions, designated as the “Monyak” case (March 2026, Eastern Rhodope Mountains, Bulgaria). A 90-day period of complete isolation involving two adult ewes and a subsequently born lamb on an inaccessible rocky ledge, with very limited access to sources of food or water, was documented. Clinical assessment performed immediately following rescue revealed profound dehydration and cachexia accompanied by multisystemic abnormalities suggestive of a prolonged catabolic state. Biochemical analysis demonstrated marked azotemia, characterized by elevated serum urea and creatinine concentrations, which may indicate reduced renal perfusion and intensified protein catabolism. Electrolyte disturbances, including hypernatremia and hyperchloremia, were compatible with severe dehydration and substantial disruption of water−electrolyte homeostasis. Furthermore, increased total serum protein concentration and hematocrit values were observed, consistent with pronounced hemoconcentration. The metabolic profile demonstrated alterations in glucose homeostasis together with enhanced ketogenesis, findings compatible with an adaptive metabolic response to sustained energy deprivation. Elevated serum activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT), accompanied by increased cortisol concentrations, may reflect hepatocellular stress and activation of the hypothalamic–pituitary–adrenal (HPA) axis associated with chronic physiological stress. Hematological evaluation revealed neutrophilia and lymphopenia, constituting a leukocyte pattern compatible with a stress leukogram and suggestive of endogenous glucocorticoid stimulation. Morphological examination of peripheral blood smears demonstrated pronounced echinocytosis and increased relative cellular density secondary to plasma volume depletion associated with dehydration. Additionally, neutrophilic hypersegmentation was observed, consistent with chronic physiological stress and cellular exhaustion. Ethological assessment suggests that maternal behavior and instinctive maternal care played a pivotal role in ensuring neonatal survival under conditions of extreme resource scarcity and sustained environmental stress. In conclusion, the “Monyak” case provides a unique natural model for investigating the physiological, metabolic, and behavioral adaptive mechanisms of ruminants subjected to prolonged starvation, dehydration, and chronic stress. The findings contribute valuable insights to veterinary physiology, clinical pathophysiology, and ethology, with potential implications for understanding the limits of adaptive capacity and survival under extreme environmental conditions. Full article

Background: Rickettsioses are emerging diseases worldwide caused by intracellular bacteria of the genus Rickettsia. In recent years, these diseases have caused deaths in northwestern Mexico, particularly cases of Rocky Mountain spotted fever (RMSF). While ticks are considered the primary vector for RMSF, other possible vectors of rickettsioses, such as fleas, lice, and mosquitoes, coexist with reservoirs, including dogs, cats, and other domestic animals that may interact with humans. This study aimed to detect the presence of Rickettsia spp., including spotted fever group (SFG) Rickettsia, in arthropod vectors not previously reported in northwestern Mexico using real-time polymerase chain reaction (qPCR). Methods: Ticks, fleas, lice, and mosquitoes were collected from dogs, cats, guinea pigs, and humans. qPCR was used to detect Rickettsia spp. and SFG Rickettsia. Results: Rickettsia spp. were detected in dog ticks (Rhipicephalus sanguineus) and cat fleas (Ctenocephalides felis), with pooled positivity rates of 13.5% and 22.2%, respectively. Conclusions: These results suggest that ticks and fleas are the main arthropod vectors involved in transmitting Rickettsia spp. in northwestern Mexico. Full article

The restoration of karst rocky desertification is reflected not only in the reduction in severely degraded areas but also in the stability of the restoration process and the potential risk of future reversal. Taking southeastern Yunnan, China, as the study area, this study constructed a six-period rocky desertification grade sequence for the years 2000, 2005, 2010, 2015, 2020, and 2024 using Landsat imagery, CLCD land-cover data, and DEM-derived slope constraints. Area change analysis, grade-transition matrices, Sen–MK trend analysis, coefficient of variation (CV), Markov–PLUS scenario simulation, scenario-sensitivity analysis, and PLUS driver contribution assessment were integrated into a process-oriented diagnostic framework to examine rocky desertification recovery from three dimensions: grade-structure adjustment, trend-variability stability, and potential future reversal risk. The results indicate that rocky desertification in southeastern Yunnan generally weakened from 2000 to 2024. The proportion of moderate-and-above rocky desertification decreased from 50.32% to 28.58%, while non-rocky desertification and potential rocky desertification expanded substantially. Grade transitions were dominated by gradual conversions among adjacent classes, with the most evident improvement occurring during 2010–2015, when the proportion of improvement transitions reached 44.16%. The trend-variability analysis indicated that while improvement dominated the study area overall, the northern, northwestern, central mountainous, and parts of the southwestern areas still exhibited relatively strong variability and localized deterioration risk. Hindcast validation showed relatively high map-level consistency between simulated and historical patterns, with an overall accuracy of 0.9354 and a Kappa coefficient of 0.9153. The three-scenario comparison further showed that the proportion of moderate-and-above rocky desertification varied from 28.07% to 29.41% in 2030 and from 26.85% to 29.06% in 2035 under different transition-probability assumptions. Specifically, the ecological restoration enhancement scenario reduced projected moderate-and-above rocky desertification, whereas the degradation pressure scenario increased it relative to the baseline scenario. These findings indicate that rocky desertification recovery in southeastern Yunnan is not a continuous or linear process, but is characterized by stage-specific adjustment, spatial differentiation, and local variability. Therefore, future rocky desertification control should focus not only on reducing high-severity areas, but also on maintaining restoration stability, identifying variability-sensitive transitional zones, and strengthening differentiated management in areas where terrain constraints, land-cover proximity, and historical variability jointly increase reversal risk. Full article

The geographic distribution of forest and woodland ecosystems in the Interior West United States is strongly influenced by topographic factors that, in part, control moisture availability through their effect on insolation, precipitation capture, and retention. Through an empirical approach, we use unique, plot-level data from the Forest Inventory and Analysis Program (n = 13,437) over eight ecoregions within eight Interior West states to characterize the distribution of the 12 most abundant tree species with respect to the effects of elevation, slope aspect, and slope steepness. Across species, elevation, and aspect, most forested plots occurred on gentle slopes and the number decreased with increasing slope. Species-specific differences in microenvironmental conditions were evident in the variation between observed (plots containing a subject tree) and expected (all forest plots from the systematic sample) numbers of plots across the gradient combinations. Species groups, broadly defined as woodland, montane, and subalpine, generally exhibited similar responses and revealed more generality than hypothesized. Only Douglas-fir, white fir, subalpine fir, and Engelmann spruce exhibited significant patterns of affinity for particular aspects—most often on north and least often on south—with the relative importance of south aspects decreasing with increasing elevation. Limber pine showed unique, unimodal patterns of affinity for moderately steep slopes, with no consistent patterns by aspect or elevation. Although not significant, at high elevations, woodland species exhibited a tendency to occur more often on south aspects on gentle to intermediate slopes, and less often on north aspects. Unique microenvironments created by interactions between aspect, slope, and elevation create some predictability in the patterns of where species occur. While there were predictable and significant patterns for a few important montane and subalpine species, most species examined lacked any significant relationships to slope, slope aspect, or elevation, suggesting that patterns of occurrence in relation to physiographic factors are much broader than in common generalizations. Full article

This study examines disciplinary differences in approaches to sustainability education among faculty in engineering, nursing, and environmental and sustainability studies at a large Rocky Mountain university. Researchers investigate how these disciplines conceptualize and implement sustainability education, as well as faculty perspectives on curricular content as they relate to the United Nations Sustainable Development Goals (SDGs). The study further examines barriers to sustainability education in relation to the broader state and national political climate. This research addresses a notable need in the literature by strengthening sustainability education content across disciplines, particularly where important aspects receive less emphasis. The manuscript concludes with recommendations for professionals seeking to integrate and advocate for sustainability across the curriculum. Full article

Rocky Mountain spotted fever (RMSF), caused by Rickettsia rickettsii, is a potentially severe tick-borne disease affecting both dogs and humans. While commercial in-clinic diagnostic tests have improved the detection of several common canine tick-borne diseases, RMSF is not routinely included in many point-of-care screening panels. In addition, infected dogs may present with subtle or nonspecific clinical signs, making diagnosis challenging. This retrospective observational study evaluated the occurrence of PCR-confirmed Rickettsia rickettsii infection in dogs presented to a veterinary lameness and performance referral center. From March 2022 through February 2024, a convenience sample of 51 dogs underwent RMSF testing as part of their diagnostic evaluation. Blood samples were analyzed using a commercial vector-borne disease PCR panel. Overall, 13 of 51 dogs (25.5%) were PCR-positive for Rickettsia rickettsii. Thirty-six dogs originated from North Carolina and South Carolina, of which 13 (36.1%) were PCR-positive. These findings suggest that RMSF should be considered among the differential diagnoses in dogs presenting with unexplained lameness, reduced athletic performance, or other nonspecific clinical concerns in regions where tick-borne diseases are common. The identification of PCR-confirmed Rickettsia rickettsii infection in this referral population highlights the potential value of expanded vector-borne disease testing. Full article

In rocky mountainous regions characterized by shallow, barren soils and water scarcity, non-rainfall water, such as condensation, plays a crucial ecological role in mitigating seasonal drought in forest trees. To enhance the water-use capacity of vegetation, this study utilized a previously developed eco-friendly PVA–CS/SA–Ca²⁺ hydrogel. The primary objective was to elucidate the synergistic mechanisms by which the hydrogel optimizes condensed water utilization and drives the ecophysiological recovery of Pinus tabuliformis and Platycladus orientalis, two keystone afforestation species in northern China. Utilizing a controlled environmental chamber to simulate the condensation and humidification process, the experiment established three treatments: a control group (CK), a pot-sealed group (PS, to isolate soil water absorption), and a hydrogel-amended group (Hydrogel-Root Wrapping, HRW). To comprehensively evaluate the water utilization mechanisms, the amount of condensed water captured by the system was quantified, and hydrogen isotope tracing techniques were employed to precisely track water transport pathways and contribution rates. Concurrently, key physiological parameters were systematically determined, including leaf water potential, stomatal conductance, leaf water content, net photosynthetic rate, and transpiration rate. The results demonstrated the following: (1) the hydrogel significantly enhanced the condensation water capture capacity of the system. The net mass gains of the Pinus tabuliformis and Platycladus orientalis systems under the HRW treatment reached 26.3 g and 32.9 g, respectively, which represented 1.17 and 1.30 times those of the CK treatment, and 1.52 and 1.54 times those of the PS treatment. (2) Isotope tracing confirmed that both tree species possess significant Foliar Water Uptake (FWU) capacity. Following condensation, the δ²H values in the leaves of Platycladus orientalis and Pinus tabuliformis surged to 113.5‰ and 85.3‰, respectively, with stem δ²H values increasing by 31‰ and 22‰ compared to their initial baseline. (3) The introduction of the hydrogel in the HRW treatment provided 11.2% and 10.9% of the stem water supply for Platycladus orientalis and Pinus tabuliformis, respectively, thereby reducing their dependence on soil water by 8.3% and 13.1%. In contrast, there was no significant difference in the fractional contribution of condensation water to stem water between the PS and CK treatments. (4) Regarding physiological responses, the application of the hydrogel material effectively improved the physiological status of the plants. The leaf water potentials of Pinus tabuliformis and Platycladus orientalis increased to −0.15 MPa and −1.32 MPa, respectively. Concurrently, stomatal conductance (3.25 and 3.64 mm·s⁻¹) and leaf water content (58.4% and 67.4%) were significantly higher than those in the other treatments. In summary, the hydrogel can significantly enhance the capture, conversion, and utilization efficiency of condensation water by vegetation, effectively optimizing the water supply dynamics of the system. This provides key theoretical and technical support for ecological afforestation in difficult sites within rocky mountainous areas. Full article

Global Navigation Satellite Systems (GNSS)-denied environments pose significant challenges for autonomous drone navigation, requiring robust visual localization systems capable of real-time performance. Existing approaches either sacrifice accuracy for speed or fail to adapt to varying flight altitudes and orientations, limiting their practical deployment. We present Real-Time Elevation and Orientation-Aware Localization Architecture (REOLA), a visual localization system that combines similarity-driven autonomous window sizing, element-wise correlation-based orientation detection, and reinforcement learning with human feedback (RLHF) enhancement for publicly available satellite imagery. On desktop hardware (i7-10700K + RTX 3070), the REOLA achieved approximately 59 FPS performance with sub-5-m accuracy across diverse flight conditions through intelligent similarity-based matching, combined with efficient MobileNet-V3 embeddings and FAISS similarity search. For embedded deployment on NVIDIA Jetson Orin Nano, the system achieved 22.5 FPS, meeting real-time requirements for autonomous drone localization. The system autonomously selects optimal window sizes corresponding to the current elevation and determines drone orientation through element-wise correlation scoring across discrete rotation angles. Enhanced through RLHF, the REOLA achieved a $97.1\%$ success rate (sub-5-m localization) while processing frames in 17 milliseconds on desktop hardware (44.4 ms on embedded hardware), providing a substantial margin over real-time requirements. The approach demonstrates particular superiority over traditional keypoint-based methods in challenging environments with repetitive patterns such as agricultural fields, rocky mountains, dense forests, and grasslands, where conventional keypoint detection struggles. We explicitly identify featureless sand dune deserts and open-sea or coastal water flights as out of scope, since the reference satellite imagery in those regimes does not contain stable landmarks. Full article

Orographic cirrus clouds frequently occur over mountainous regions and can influence the radiative balance of the upper troposphere, yet their characteristics and regional variability remain insufficiently understood on a global scale. In this study, we investigate the occurrence, vertical structure, and microphysical and optical properties of orographic cirrus over four major mountainous regions, namely the Rocky Mountains, the Andes, the Alps, and the Himalayas, using the Identification and Classification of Cirrus (IC-CIR) framework together with satellite observations from MODIS, CloudSat, and CALIPSO. The results reveal clear regional differences in both occurrence and structure. Cloud cover is higher over the Himalayas and the Alps and lower over the Andes, while seasonal variability is strongest over the Himalayas and the Alps and weakest over the Andes. In terms of vertical structure, cirrus over the Andes reaches higher cloud tops and exhibits a bimodal distribution. The Andes also show smaller values of ice water path, optical depth, and cirrus reflectance. These results provide a unified comparison of orographic cirrus clouds across four representative major mountainous regions and highlight substantial regional differences in their characteristics and potential radiative influence under different topographic and dynamical environments. Full article

The Carpathian Mountains are an important hotspot of European biodiversity, where geological history, climatic diversity, and altitudinal heterogeneity have determined a great diversity and endemism of vascular plants. The study was conducted in the national park of Piatra Craiului, a distinctive limestone massif in the Southern Carpathians. The dataset included 731 vascular plant species from the study area, of which 35 taxa are endemic to the Carpathians (of the 47 reported in this area), and 18 are classified as species of conservation interest in the Management Plan of the National Park (MP). The distribution of endemic species showed different habitat and altitudinal specificity across 15 vegetation types, including 14 Natura 2000 habitats and one outside the EUR 28 classification. The endemic species showed a bell-shaped altitudinal distribution, peaking at 1600–1700 m and concentrated in high-altitude open habitats rather than forested mid-elevations. The PCA separates endemic species along a main gradient from open, disturbed, light-rich habitats to stable, nutrient- and moisture-rich forest environments, and a secondary gradient related to temperature and soil reaction linked to altitude. Endemic species are predominantly associated with calcareous rocky and grassland habitats and are almost absent from mesophilic and hygrophilous habitats. A positive association between endemic species frequency and the total number of species of conservation interest per plot was detected. We concluded that species of conservation interest (such endemic species) are unevenly distributed among habitat types in the Carpathians, with the greatest diversity and abundance in subalpine rocky and grassland habitats, shaped by altitude and isolation. Although the threatened endemic species are not officially listed by national law, they are indirectly protected by management zonation. In Piatra Craiului the richest habitats in endemic species are included in the designated zones of the national park with the highest protection regime, according to the National Park’s Management Plan. Moreover, this territory is included in a Natura 2000 site (ROSAC0194 Piatra Craiului) ensuring an additional level of protection for the habitats where endemic species are found. Full article

Alternanthera philoxeroides is a highly invasive alien species in China that causes waterway blockages, agricultural yield loss, biodiversity decline, and ecosystem degradation. This study assessed the invasion risk and environmental drivers of A. philoxeroides in Guizhou Province, a karst mountainous region in Southwest China. Occurrence records were obtained from field surveys and the Chinese Virtual Herbarium. The genetic algorithm for rule-set production (GARP) model and the jackknife method were employed to identify 13 key environmental indicators for predicting invasion risk. The global invasion risk index (GIRI) was applied to quantify the overall invasion risk. Additionally, the Geodetector model was utilized to analyze the spatially differentiated effects of six environmental factors. The results showed that A. philoxeroides poses a high invasion risk in Guizhou Province, and the invasion risk in the Yangtze River Basin within Guizhou is higher than that in the Pearl River Basin. The environmental factors influencing invasion risk, in order of impact, were slope, elevation, land use, river density, rocky desertification, and soil pH. Moreover, interactions among these factors further amplify the invasion risk. These findings provide valuable insights for developing targeted management strategies for A. philoxeroides in karst mountainous regions and support biodiversity preservation and regional ecological sustainability. Full article

Located on the traditional and ancestral homelands of the Arapaho, Cheyenne, and Ute Nations, Colorado State University’s Mountain Campus hosted the 25th Annual Rocky Mountain Virology Association meeting. The three-day event, held from 26 September to 28 September 2025, welcomed 152 participants focused on the following topics: viruses, prions, immunology, transmission, structural biology, and vector biology. This year’s Randall Jay Cohrs Keynote Presentation summarized ongoing research on viral glycoproteins in relation to viral entry and assembly. Understanding the role of viral glycoproteins is essential in vaccine and antiviral development for enveloped RNA viruses. Alongside rigorous scientific discourse and networking, attendees made the most of their time by hiking amidst beautiful fall colors, wildlife, and young aspens starting the forest anew. On behalf of the Rocky Mountain Virology Association, this report summarizes select presentations from the 25th annual meeting. Full article

Soil preferential flow plays a crucial role in governing hydrological cycles and soil moisture distribution in mountain forests. This makes it essential for understanding subsurface water movement and for guiding hillslope hydrological management. In this study, soil preferential flow, soil properties, and root characteristics across three slope positions on a Larix gmelinii var. principis-rupprechtii (Mayr) Pilger (larch) plantation hillslope in the Liupan Mountains were systematically observed to reveal the spatial patterns and formation mechanisms of hillslope soil preferential flow. The results showed that soil preferential flow development followed a distinct spatial pattern across the slope positions, with the mid-slope exhibiting the most developed preferential flow characteristics. The comprehensive preferential flow index further quantified this spatial variation, ranking the slope positions as mid-slope > upper slope > lower slope. Different soil structural properties exerted varying influences on preferential flow. Macropore-related properties (low bulk density and high porosity and saturated conductivity) promoted most preferential flow, whereas aggregate-related properties (high organic matter and water-stable aggregates) suppressed it. The influence of root characteristics on preferential flow was also dual. Root length density generally promoted preferential flow (e.g., DC, LI, and UniFr), whereas root surface area density primarily exerted an inhibitory effect (e.g., LI, UniFr, and total stained area TotStAr). This study clarifies how slope position modulates preferential flow through soil and root characteristics, offering insights for slope-specific hydrological understanding and targeted soil and water conservation practices. Full article