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Currently available European Alpine Altitude Climate Treatment (AACT) programs combine the physical characteristics of altitude with the avoidance of environmental triggers in the alpine climate and a personalized multidisciplinary pulmonary rehabilitation approach. The reduced barometric pressure, oxygen pressure, and air density, the relatively low temperature and humidity, and the increased UV radiation at moderate altitude induce several physiological and immunological adaptation responses. The environmental characteristics of the alpine climate include reduced aeroallergens such as house dust mites (HDM), pollen, fungi, and less air pollution. These combined factors seem to have immunomodulatory effects controlling pathogenic inflammatory responses and favoring less neuro-immune stress in patients with different asthma phenotypes. The extensive multidisciplinary treatment program may further contribute to the observed clinical improvement by AACT in asthma control and quality of life, fewer exacerbations and hospitalizations, reduced need for oral corticosteroids (OCS), improved lung function, decreased airway hyperresponsiveness (AHR), improved exercise tolerance, and improved sinonasal outcomes. Based on observational studies and expert opinion, AACT represents a valuable therapy for those patients irrespective of their asthma phenotype, who cannot achieve optimal control of their complex condition despite all the advances in medical science and treatment according to guidelines, and therefore run the risk of falling into a downward spiral of loss of physical and mental health. In the light of the observed rapid decrease in inflammation and immunomodulatory effects, AACT can be considered as a natural treatment that targets biological pathways., (© 2022 The Authors. Allergy published by European Academy of Allergy and Clinical Immunology and John Wiley & Sons Ltd.)

Millions of people visit high-altitude regions annually and more than 80 million live permanently above 2,500 m. Acute high-altitude exposure can trigger high-altitude illnesses (HAIs), including acute mountain sickness (AMS), high-altitude cerebral oedema (HACE) and high-altitude pulmonary oedema (HAPE). Chronic mountain sickness (CMS) can affect high-altitude resident populations worldwide. The prevalence of acute HAIs varies according to acclimatization status, rate of ascent and individual susceptibility. AMS, characterized by headache, nausea, dizziness and fatigue, is usually benign and self-limiting, and has been linked to hypoxia-induced cerebral blood volume increases, inflammation and related trigeminovascular system activation. Disruption of the blood-brain barrier leads to HACE, characterized by altered mental status and ataxia, and increased pulmonary capillary pressure, and related stress failure induces HAPE, characterized by dyspnoea, cough and exercise intolerance. Both conditions are progressive and life-threatening, requiring immediate medical intervention. Treatment includes supplemental oxygen and descent with appropriate pharmacological therapy. Preventive measures include slow ascent, pre-acclimatization and, in some instances, medications. CMS is characterized by excessive erythrocytosis and related clinical symptoms. In severe CMS, temporary or permanent relocation to low altitude is recommended. Future research should focus on more objective diagnostic tools to enable prompt treatment, improved identification of individual susceptibilities and effective acclimatization and prevention options., (© 2024. Springer Nature Limited.)

The sea level along the US coastlines is projected to rise by 0.25-0.3 m by 2050, increasing the probability of more destructive flooding and inundation in major cities 1-3 . However, these impacts may be exacerbated by coastal subsidence-the sinking of coastal land areas 4 -a factor that is often underrepresented in coastal-management policies and long-term urban planning 2,5 . In this study, we combine high-resolution vertical land motion (that is, raising or lowering of land) and elevation datasets with projections of sea-level rise to quantify the potential inundated areas in 32 major US coastal cities. Here we show that, even when considering the current coastal-defence structures, further land area of between 1,006 and 1,389 km 2 is threatened by relative sea-level rise by 2050, posing a threat to a population of 55,000-273,000 people and 31,000-171,000 properties. Our analysis shows that not accounting for spatially variable land subsidence within the cities may lead to inaccurate projections of expected exposure. These potential consequences show the scale of the adaptation challenge, which is not appreciated in most US coastal cities., (© 2024. The Author(s).)

This paper provides the official recommendation of the Union Internationale des Associations d'Alpinisme (UIAA) Medical Commission to manage the problem of safe drinking water. The recommendation was accepted and authorized for publication by the Medical Commission during their annual meeting at Treplice, Tzechia, 2008. Safe water is essential for mountaineers worldwide in order to balance challenges associated with high altitude dehydration. The paper summarizes the advantages and disadvantages of several procedures used to procure safe drinking water in the mountains or at high altitude. Limitations or critical details, which may cause failure of the methods are mentioned systematically. We differentiate between "conventional" methods, which should be preferred because they produce safe water and "improvisation". The latter does not produce safe water but may be used if conventional methods are not available for any reason. They decrease the concentration of pathogenic microorganisms and by this they reduce the risk of enteral infection. Water filtration using a ceramic filter system or chemical disinfection is recommended as a standard method. Boiling water should be avoided because it is too fuel consuming and has the potential to increase deforestation. Generally, with regard to infections by water or food, all mountaineers should be vaccinated against hepatitis A and poliomyelitis in regions where they may be at-risk.

The study of elevational diversity gradients dates back to the foundation of biogeography. Although elevational patterns of plant and animal diversity have been studied for centuries, such patterns have not been reported for microorganisms and remain poorly understood. Here, in an effort to assess the generality of elevational diversity patterns, we examined soil bacterial and plant diversity along an elevation gradient. To gain insight into the forces that structure these patterns, we adopted a multifaceted approach to incorporate information about the structure, diversity, and spatial turnover of montane communities in a phylogenetic context. We found that observed patterns of plant and bacterial diversity were fundamentally different. While bacterial taxon richness and phylogenetic diversity decreased monotonically from the lowest to highest elevations, plants followed a unimodal pattern, with a peak in richness and phylogenetic diversity at mid-elevations. At all elevations bacterial communities had a tendency to be phylogenetically clustered, containing closely related taxa. In contrast, plant communities did not exhibit a uniform phylogenetic structure across the gradient: they became more overdispersed with increasing elevation, containing distantly related taxa. Finally, a metric of phylogenetic beta-diversity showed that bacterial lineages were not randomly distributed, but rather exhibited significant spatial structure across the gradient, whereas plant lineages did not exhibit a significant phylogenetic signal. Quantifying the influence of sample scale in intertaxonomic comparisons remains a challenge. Nevertheless, our findings suggest that the forces structuring microorganism and macroorganism communities along elevational gradients differ.

Many pathological conditions exist where tissues exhibit hypoxia or low oxygen tension. Hypoxic hypoxia arises when there is a reduction in the amount of oxygen entering the blood and occurs in healthy people at high altitude. In 1946, research sponsored by the United States Navy led to the collection and subsequent publication of masses of data demonstrating the physiological consequences and adaptations of ascent to high altitude. This article describes how a figure from a 1947 paper from the American Physiological Society Legacy collection (Houston CS, Riley RL. Respiratory and circulatory changes during acclimatization to high altitude. Am J Physiol 149: 565-588) may be used to allow students to review their understanding of some of the generalized effects of hypoxia on the body. In particular, this figure summarizes some of the adaptive responses that take place in the oxygen transport system as a consequence of prolonged hypoxia.

Aerial light detection and ranging (lidar) has emerged as a powerful technology for mapping urban archaeological landscapes, especially where dense vegetation obscures site visibility 1,2 . More recently, uncrewed aerial vehicle/drone lidar scanning has markedly improved the resolution of three-dimensional point clouds, allowing for the detection of slight traces of structural features at centimetres of detail across large archaeological sites, a method particularly useful in areas such as mountains, where rapid deposition and erosion irregularly bury and expose archaeological remains 3 . Here we present the results of uncrewed aerial vehicle-lidar surveys in Central Asia, conducted at two recently discovered archaeological sites in southeastern Uzbekistan: Tashbulak and Tugunbulak. Situated at around 2,000-2,200 m above sea level, these sites illustrate a newly documented geography of large, high-altitude urban centres positioned along the mountainous crossroads of Asia's medieval Silk Routes (6th-11th century CE (Common Era) 4,5 . Although hidden by centuries of surface processes, our pairing of very-high-resolution surface modelling with semiautomated feature detection produces a detailed plan of monumental fortifications and architecture spanning 120 ha at Tugunbulak, thereby demonstrating one of the largest highland urban constellations in premodern Central Asia. Documentation of extensive urban infrastructure and technological production among medieval communities in Central Asia's mountains-a crucial nexus for Silk Road trade networks 6 -provides a new perspective on the participation of highland populations in the economic, political and social formation of medieval Eurasia., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

This is the first report on high pesticide tolerance displayed by the microbiota isolated from the sediments of two high-altitude lakes, located in the Singalila National Park, Singalila Ridge of the Himalayas. Given the remote location of these lakes, direct exposure to chemical pesticides is highly unlikely. However, the high tolerance to commonly used pesticides exhibited, i.e. up to 250 mg/ml, suggests repeated exposure and contamination of the lakes. Microbial growth in the presence of varying concentrations of the pesticides, namely, emamectin benzoate, thiamethoxam, quinalphos, deltamethrin, spiromesifen, flubendiamide, monocrotophos, fipronil, fenazaquin and phorate, was tested. Results showed resistance to all pesticides except fenazaquin and fipronil, up to 250 mg/ml. For the latter two, tolerance was displayed up to a concentration of 40 mg/ml. Tolerance may potentially result from the transport and deposition of pesticides from nearby locations, particularly the tea plantations of Darjeeling and Eastern Nepal. This may create great ecological risks as these lakes are an important water source for endemic wildlife of this protected area. They also hold great significance to the religious sentiment of the local tribes who worship these lakes as sacred. The study highlights the need for monitoring pesticide contamination in such pristine high-altitude environments and the mechanisms of long-range pollutant transport., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Background: Markers of airway inflammation can be helpful in the management of childhood asthma. Residential activities, such as intensive asthma camps at alpine altitude climate (AAC), can help reduce bronchial inflammation in patients who fail to achieve optimal control of the disease. Analysis of volatile organic compounds (VOCs) can be obtained using electronic devices such as e-Noses. We aimed to identify alterations in urinary e-Nose sensors among children with asthma participating in an intensive camp at AAC and to investigate associations between urinary e-Nose analysis and airway inflammation., Methods: We analyzed data collected in children with asthma recruited between July and September 2020. All children were born and resided at altitudes below 600 m asl. Urinary VOCs (measured using the Cyranose 320® VOC analyzer), Fractional exhaled Nitric Oxide (FeNO) and spirometry were evaluated upon children's arrival at the Istituto Pio XII, Misurina (BL), Italy, at 1756 m asl (T0), and after 7 (T1) and 15 days (T2) of stay., Results: Twenty-two patients (68.2% males; median age: 14.5 years) were enrolled. From T0 to T1 and T2, the negative trend for FeNO was significant (p < .001). Significant associations were observed between e-Nose sensors S7 (p = .002), S12 (p = .013), S16 (p = .027), S17 (p = .017), S22 (p = .029), S29 (p = .021), S31 (p = .009) and ΔFeNO at T0-T1. ΔFeNO at T0-T2 was significantly associated with S17 (p = .015), S19 (p = .004), S21 (p = .020), S24 (p = .012), S25 (p = .018), S26 (p = .008), S27 (p = .002), S29 (p = .007), S30 (p = .013)., Conclusions: We showed that a decrease in FeNO levels after a short sojourn at AAC is associated with behaviors of individual urinary e-Nose sensors in children with asthma., (© 2024 Wiley Periodicals LLC.)

Pilot studies are presently being carried out to determine the efficacy of raising the oxygen concentration in the room air of commercial and scientific facilities at altitudes of 4000-5500 m. This is a remarkably effective way of relieving hypoxia. For example, oxygen enrichment by only 5% (i.e., raising the oxygen concentration from 21 to 26%) reduces the equivalent altitude by 1500 m. However, concern has been expressed about the possibility of fire hazard. In this article, existing data from various sources have been analyzed to determine the burning rate of materials such as paper and cotton clothing at various altitudes when the PO2 in the air is increased to 110 mmHg to give an equivalent altitude of 3000 m. The analysis shows that in spite of the increase in oxygen concentration, the burning rate is much less than at sea level primarily because the PO2 is so much lower even with oxygen enrichment.

In insects, different pigments, such as melanins and pterins, are involved in thermoregulation. The degree of melanisation often varies along geographical gradients, according to the so-called thermal melanism hypothesis, i.e. darker forms are found in colder places because they can warm up more quickly. Similarly, pterins work as heat sinks and thus are expected to be more abundant in colder sites. Cities, which are warmer than surrounding areas (Urban Heat Island (UHI) effect), might also be expected to influence pigmentation, although studies are lacking. Here, we sampled workers of the social paper wasp Polistes dominula (Christ, 1791) (Vespidae) across an urbanisation gradient in an Italian metropolis and used iNaturalist pictures of this species across Italy to study pigmentation patterns at both urban and larger geographical scales. We found a lower yellow intensity of abdominal spots at warmer locations. Scanning Electron Microscopy strongly suggested that yellow colouration is due xanthopterin, known to be the heat sink molecule in other social vespids. Thus, wasps from warmer (i.e., urban) environments are likely to have fewer xanthopterin granules, in line with the lack of need for heat storage due to the local thermal gradient (UHI effect). At the country level, we found that wasps at higher latitudes had smaller yellow spots on the thorax and only two spots instead of four at higher altitudes, in full accordance with the thermal melanism hypothesis. In conclusion, climatic conditions seem to affect insect colour patterns both along urban and wider geographical gradients, although colour changes may affect different body parts and pigments likely according to different needs. • In urban hotter sites, workers show lower intensity of yellow pigmentation (xanthopterin). • Along an urbanisation gradient, there was weak consistence with the thermal melanism hypothesis. • Along the same gradient, there was a likely lack of need for heat storage due to the urban heat island effect. • At country level, latitudinal variations in yellow spots were in accordance with the thermal melanism hypothesis. [ABSTRACT FROM AUTHOR]

Research focused on understanding the evolutionary factors that shape parity mode evolution among vertebrates have long focused on squamate reptiles (snakes and lizards), which contain all but one of the evolutionary transitions from oviparity to viviparity among extant amniotes. While most hypotheses have focused on the role of cool temperatures in favoring viviparity in thermoregulating snakes and lizards, there is a growing appreciation in the biogeographic literature for the importance of lower oxygen concentrations at high elevations for the evolution of parity mode. However, the physiological mechanisms underlying how hypoxia might reduce fitness, and how viviparity can alleviate this fitness decrement, has not been systematically evaluated. We qualitatively evaluated previous research on reproductive and developmental physiology, and found that (1) hypoxia can negatively affect fitness of squamate embryos, (2) oxygen availability in the circulatory system of adult lizards can be similar or greater than an egg, and (3) gravid females can possess adaptive phenotypic plasticity in response to hypoxia. These findings suggest that the impact of hypoxia on the development and physiology of oviparous and viviparous squamates would be a fruitful area of research for understanding the evolution of viviparity. To that end, we propose an integrative research program for studying hypoxia and the evolution of viviparity in squamates., (© 2021 Wiley Periodicals LLC.)

Considering the importance of limited natural resources, accurately recording and evaluating temperature data is critical. The daily average temperature values obtained for the years 2019-2021 of eight highly correlated meteorological stations, characterized by mountainous and cold climate features in the northeast of Turkey, were analyzed by an artificial neural network (ANN), support vector regression (SVR), and regression tree (RT) methods. Output values produced by different machine learning methods compared with different statistical evaluation criteria and the Taylor diagram. ANN6, ANN12, medium gaussian SVR, and linear SVR were chosen as the most suitable methods, especially due to their success in estimating data at high (> 15 ℃) and low (< 0 ℃) temperatures. All the methodologies and network architectures used produced successful results (NSE-R 2  > 0.90). Some deviations have been observed in the estimation results due to the decrease in the amount of heat emitted from the ground due to fresh snow, especially in the -1 ~ 5 ℃ range, where snowfall begins, in the mountainous areas characterized by heavy snowfall. In models with low neuron numbers (ANN1,2,3) in ANN architecture, the increase in the number of layers does not affect the results. However, the increase in the number of layers in models with high neuron counts positively affects the accuracy of the estimation., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Background: Human populations native to high altitude exhibit numerous genetic adaptations to hypobaric hypoxia. Among Tibetan plateau peoples, these include increased vasodilation and uncoupling of erythropoiesis from hypoxia., Objective/methods: We tested the hypothesis that these high-altitude adaptations reduce risk for hypertension and diabetes-associated anemia among the Mosuo, a Tibetan-descended population in the mountains of Southwest China that is experiencing rapid economic change and increased chronic disease risk., Results: Hypertension was substantially less common among Mosuo than low-altitude Han populations, and models fit to the Han predicted higher probability of hypertension than models fit to the Mosuo. Diabetes was positively associated with anemia among the Han, but not the Mosuo., Conclusion: The Mosuo have lower risk for hypertension and diabetes-associated anemia than the Han, supporting the hypothesis that high-altitude adaptations affecting blood and circulation intersect with chronic disease processes to lower risk for these outcomes. As chronic diseases continue to grow as global health concerns, it is important to investigate how they may be affected by local genetic adaptations., (© 2020 Wiley Periodicals, Inc.)

Objective: The purpose of this systematic review was to synthesize the existing global literature examining the relationship between altitude and suicide., Method: Using the electronic databases PubMed, CINAHL, EMBASE, and PsychInfo published articles in English that addressed the relationship between altitude and suicide as a primary or secondary aim, and included human subjects, where identified. Studies were assessed for quality based on methodological approach and data relevance on a three-point scale (strong, moderate, or weak)., Results: Of the 19 studies related to the purpose and aims, 17 reported evidence of a positive correlation between altitude and increased suicide. Vast design differences were employed within the literature, individual-level suicide data was identified as the preferred level of analysis., Discussion: The relationship between altitude and suicide is an evolving science with a small but growing body of literature suggesting altitude is associated with an increased risk of suicide. This review identifies the need for additional studies examining both individual-level suicide data and improving geographic precision. Public health nurses have a responsibility to carefully examine the quality of studies and the strength of the evidence when addressing variables associated with suicide., (© 2022 Wiley Periodicals LLC.)