Marked Transition Research Articles

Steppe development and mammalian adaptation in the middle Miocene, North Junggar Basin, Central Asia

The Central Asian (CA) steppe ecosystem and its fauna experienced a marked transition during the Miocene Climatic Optimum (MCO), though the exact process and dynamics remain elusive. We selected the Duolebulejin (DLB) section within the Junggar Basin to reconstruct vegetation and climate changes, using proxies such as particle size, mammalian fossils, and previously reported data including pollen, δ13CTOC, and magnetic susceptibility. The results reveal three distinct phases of transformation in regional vegetation and fauna from 18.8 to 13.2 Ma. During the pre-MCO (18.8–17.0 Ma), the landscape was dominated by desert scrubland, primarily inhabited by rodents. The MCO (17.0–14.5 Ma) saw a shift towards steppe vegetation, initially with herbaceous taxa followed by the establishment of C4 plants, alongside a diversity of large mammals adapted to open habitats. This suggests the emergence of savanna-like woodland steppes. In the post-MCO (14.5–13.2 Ma), the region transitioned to a dry steppe, with diminished animal populations, although a continued high proportion of species adapted to steppe environments. These findings underscore a co-evolutionary relationship between the development of steppe ecosystems and mammalian adaptations, driven by global MCO warming and subsequent cooling and with regional hydroclimatic changes acting as a modulating factor. The steppe-fauna biome emerged in the Junggar Basin during the MCO warming, a development whose mechanisms resemble those of tropical savannas in the late Miocene. These insights enhance our understanding of early steppe ecosystem evolution through past warming periods, shedding light on the pathways to modern steppe formation.

Haruki Murakami: A Global Literary Journey from Japan to the World

In a world increasingly shaped by globalization, the migration of literature across borders has become more fluid and pervasive than ever before. This phenomenon extends beyond literature to encompass music, film, and other forms of art, facilitated by advancements in technology that grant simple access to global audiences. Haruki Murakami, one of the most important figures of modern Japanese literature, emerges as one of the prime examples of writers who have transcended national boundaries to earn international acclaim. Understanding Murakami's ascent to prominence requires acknowledging the Westernization of Japanese literature following the Meiji period. This era marked Japan's transition from an isolated feudal society to a modernized nation influenced by Western ideals. The societal shift towards Westernization, driven by aspirations of military and economic strength, altered the reception of Japanese writers in Western literary circles. Murakami's immersion in Western culture, coupled with his experiences living abroad and his deliberate incorporation of Western motifs into his works, distinguishes him from his contemporaries in the Japanese literary scene. While critics may scrutinize his portrayal of Japan and find it lacking authenticity, Murakami's global appeal lies in his ability to capture universal themes of isolation, identity, and existential angst that resonate with readers worldwide. Murakami's journey from a local Japanese author to a global literary icon exemplifies the transformative power of literature in an increasingly interconnected world. By bridging cultural divides and transcending linguistic boundaries, Murakami's works serve as a testament to the enduring impact of storytelling in uniting humanity across the vast tapestry of human experience. In this context, this study aims to discuss Murakami's journey from his origins in the Japanese literary market to his recognition on the global stage.

Viability of Structured Gait Retraining for Improving Clinical Outcomes Following Running-related Injury in Active Duty Service Members.

All branches of the U.S. Military have a running component of their physical readiness testing battery. Running-related musculoskeletal injuries affect 20 to 40% of DoD Service Members each year. Running form has not historically been addressed with military running-related injuries. To assess the utility of a structured gait retaining protocol designed to treat the onset of running-related pain and/or injury by correcting identified biomechanical risk factors for injury and improve clinical outcomes. Case series. A total of 160 Active Duty Service Members (ADSMs) with running-related lower-body musculoskeletal injuries were referred by a physical therapist for a multisession gait retraining program termed "Run with CLASS" (Cadence, Lean, Alignment, Soft-landing, Strike). Run with CLASS utilized various drills to emphasize impact progression, proximal strengthening, and proprioception and spatial awareness. Results revealed that the implemented gait retraining protocol significantly improved running parameters following lower-body injury as evidenced by increased cadence, improved functional assessment scores, and a marked transition from predominantly heel strike to forefoot strike patterns during running. A 3-week supervised gait retraining program focused on the gait retraining program termed "Run with CLASS" (Cadence, Lean, Alignment, Soft-landing, Strike) was successful in altering biomechanics of self-selected running gait by increasing cadence and transitioning ADSMs to a forefoot foot strike. Additionally, ADSMs reported significant improvements on the self-reported functional scores on the University of Wisconsin Running Injury and Recovery Index and Single Assessment Numerical Evaluation. 4.

Beyond the basics: mapping the inflation response to fiscal deficit in India with smooth transition autoregressive model

PurposeIndia’s historical fiscal performance has featured elevated deficit levels. Driven by the imperative need for fiscal stimulus measures in response to the crisis, efforts toward fiscal consolidation from 2003 to 2008 were reversed in 2008–2009 due to the financial crisis. These stimulus actions are believed to have wielded a notable influence on inflation dynamics. Presumably, a high inflation rate hinders growth and inflicts severe welfare costs. Accordingly, the principal objective of this paper is to scrutinise the threshold effects of fiscal deficit on inflation within the context of the Indian economy.Design/methodology/approachWe employed the Smooth Transition Autoregressive (STAR) Model, a robust tool for capturing non-linear relationships, to discern the specific threshold level of fiscal deficit. Our analysis encompasses annual data spanning from 1971 to 2020. Additionally, we have leveraged the Toda-Yamamoto causality test to establish the existence and direction of a causal connection between fiscal deficit and inflation in the Indian economy.FindingsOur analysis pinpointed a critical threshold level of 3.40% for fiscal deficit, a value beyond which inflation dynamics in India undergo a marked transition, signifying the presence of significant non-linear effects. Moreover, the results derived from the Toda-Yamamoto causality test offer substantiating evidence of a causal relationship originating from the fiscal deficit and leading to inflation within the Indian economic framework.Research limitations/implicationsThe findings of our study carry significant implications, particularly for the formulation and execution of both fiscal and monetary policies. Understanding the threshold effects of fiscal deficit on inflation in India provides policymakers with valuable insights into achieving a harmonious balance between these two critical economic variables.Originality/valueTo the best of our knowledge, this study is the first of its kind to empirically investigate threshold effects of fiscal deficit on inflation in India from a non-linear perspective using the Smooth Transition Autoregression (STAR) model.

When religion meets mathematics: From mathematical anxiety to mathematical well-being for minority group student

The mission of positive psychology is to mitigate negative emotions while bolstering positive ones, thereby influencing student engagement in classroom learning activities, including mathematics. This study elucidates the Realistic Mathematics Education (RME) approach within the framework of Islamic teachings—specifically, inheritance law and charity—in the context of fractions and number operations. Its objective is to alleviate mathematics anxiety, a prevalent negative emotion, and enhance well-being during mathematical learning. Drawing upon flow theory from positive psychology, the research endeavors to optimize mathematical well-being by crafting appropriately challenging questions. Employing a descriptive qualitative methodology, the study focuses on an Indonesian mother and her ten-year-old son, residing in Uithoorn, Amsterdam, Netherlands, belonging to minority groups in ethnicity and identity, with religion being a significant aspect of their lives. Data collection involves observation, interviews, tests, and documentation, with analysis employing data reduction, presentation, triangulation, and verification techniques. The study utilizes socio-religious problems as a context, one of the characteristics of RME, such as inheritance division, to design mathematical challenges. The findings demonstrate a marked transition from math anxiety to math well-being, manifested through heightened enthusiasm and cheerfulness in learning mathematics, particularly by the mother. Noteworthy transformations include increased engagement, generous gestures towards the teacher, and frequent smiling, contrasting with previous instances of math anxiety during learning sessions. Furthermore, the results indicate that RME facilitates comprehension of mathematical concepts and fosters understanding of the intersection between mathematics and Islamic life among minority groups, as detailed in this article.

Contrasting magma chemistry in the Candelaria IOCG district caused by changing tectonic regimes

Iron oxide-copper-gold (IOCG) deposits are a vital source of copper and critical elements for emerging clean technologies. Andean-type IOCG deposits form in continental arcs undergoing extension, and they have a temporal relationship with magmatism although they do not exhibit a close spatial relation with the causative intrusions. The processes required to form IOCG deposits and their potential connections to iron oxide–apatite (IOA)-type mineralization remain poorly constrained, as well as the characteristics of magmatism linked to both deposit types. Here we combine zircon U–Pb geochronology with zircon trace element geochemistry of intrusive rocks associated with the Candelaria deposit, one of the world’s largest IOCG deposits, to unravel distinctive signatures diagnostic of magmatic fertility. Our results reveal a marked transition in the geochemistry of intrusions in the Candelaria district, characterized by changes in the redox state, water content and temperature of magmas over time. The oldest magmatic stage (~ 128–125 Ma), prior to the formation of the Candelaria deposit, was characterized by zircon Eu/Eu* ratios of 0.20–0.42, and redox conditions of ΔFMQ − 0.4 to + 1.0. The earliest magmatic stage related to the formation of Fe-rich mineralization at Candelaria (118–115 Ma) exhibits low zircon Eu/Eu* ratios (0.09–0.18), low oxygen fugacity values (ΔFMQ ~− 1.8 to + 0.2) and relatively high crystallization temperatures. In contrast, the youngest stage at ~ 111–108 Ma shows higher zircon Eu/Eu* (~ 0.37–0.69), higher oxygen fugacity values (ΔFMQ ~ + 0.4 to + 1.3) and a decrease in crystallization temperatures, conditions that are favorable for the transport and precipitation of sulfur and chalcophile elements. We conclude that Candelaria was formed through two distinct ore-forming stages: the first associated with a reduced, high temperature, water-poor magma developed under a low tectonic stress, followed by a more oxidized, water-rich, and low temperature magmatic event related to a compressional regime. The first event led to Fe-rich and S-poor IOA-type mineralization, while the second event with geochemical signatures similar to those of porphyry copper systems, generated the Cu- and S-rich mineralization. This late stage overprinted preexisting IOA mineralization resulting in the formation of the giant Candelaria IOCG deposit.

Energy sovereignty storytelling: Art practices, community-led transitions, and territorial futures in Latin America

ABSTRACT In this article, we study forms of storytelling about energy sovereignty retrieved from community-based art and their implications for energy justice formulations in Latin America. Based on the visual and discursive analysis of five contemporary Latin American artistic practices, the article shows that their poetic and political engagements with energy production, consumption, and distribution build what we call “energy sovereignty storytelling.” That is, understandings of energy justice that territorialize energy technologies, thus defying Western-centered views on energy and energy infrastructure in a context of marked transitions. Combining insights from art analysis in STS with concepts from energy humanities and technological sovereignty studies, this research discusses four aspects that characterize these emergent energy storytelling practices. By bringing these four aspects together, this study shows that territory-attuned, community-based art research highlights understandings of energy beyond corporate extractivism and market interests. In this way, activating new modes of storytelling in relation to energy affords novel understandings of energy and energy infrastructure that can contribute to attaining a just and equitable energy transition in Latin America, where ancestral and local more-than-human communities can participate actively in shaping energy presents and futures.

Magnetotail Variability During Magnetospheric Substorms

AbstractIn this work, we present a statistical study of substorms covering a five‐year period 2016–2020. Substorm phases were identified from time series of the SuperMAG AL (SML) index using a list of 5,077 previously identified substorm onsets, the SML peak value marking transition from expansion to recovery phase, and the recovery identified as return to activity less than −100 nT in the SML index. Magnetic field observations from THEMIS, RBSP, and MMS missions were used to study the magnetotail characteristics during the substorm evolution. A superposed epoch analysis indicates that the substorm onset occurs almost simultaneously with a few minutes of uncertainty throughout the magnetotail, ranging from geostationary orbit to 20 RE. The onset in the transition region precedes the ground onset by a few minutes. The peak SML time coincides with the peak of the outer transition region ΔBZ, which suggests that the field‐aligned currents driving the SML activity arise from the outer transition region. Analysis of 2D maps of the tail magnetic field shows that the magnetotail current changes are limited to the center of the tail within |Y| < 10RE. The substorm recovery is fastest in the inner transition region and lasts longer when moving further out. We did not find major asymmetries in the substorm signatures associated with IMF BY or BZ.

The common good from an economic perspective: Insights from EU policies during the COVID-19

Abstract This paper delves into the diverse conceptualizations of the “common good” within the economic discourse and scrutinizes their implications for European integration during the pressing COVID-19 pandemic. Employing a comprehensive literature review, policy analysis, and case study examination, it explores the manifestations of the common good in the context of European Union policies. Two key interpretations emerge from our investigation: the first presents the common good as an ultimate objective, seeking a balance between individual and collective interests achieved via adept economic governance; the second considers it a continuous process underpinned by the principles that direct the journey toward such a balance. Our findings reveal that the EU’s response to the COVID-19 crisis led to shifts in fiscal policies and innovation strategies. The research outcomes demonstrate a marked transition in the EU’s approach, with a stronger focus on social welfare, environmental sustainability, and collective well-being.

Application of Mass Service Theory to Economic Systems Optimization Problems—A Review

An interdisciplinary approach to management allows for the integration of knowledge and tools of different fields of science into a unified methodology in order to improve the efficiency of resource management of different kinds of systems. In the conditions of global transformations, it is economic systems that have been significantly affected by external destabilizing factors. This determines the focus of attention on the need to develop tools for the modeling and optimization of economic systems, both in terms of organizational structure and in the context of resource management. The purpose of this review study is to identify the current gaps (shortcomings) in the scientific literature devoted to the issues of the modeling and optimization of economic systems using the tools of mass service theory. This article presents a critical analysis of approaches for the formulation of provisions on mass service systems in the context of resource management. On the one hand, modern works are characterized by the inclusion of an extensive number of random factors that determine the performance and efficiency of economic systems: the probability of delays and interruptions in mobile networks; the integration of order, inventory, and production management processes; the cost estimation of multi-server system operation; and randomness factors, customer activity, and resource constraints, among others. On the other hand, controversial points are identified. The analytical study carried out allows us to state that the prevailing majority of mass service models applied in relation to economic systems and resource supply optimization are devoted to Markov chain modeling. In terms of the chronology of the problems studied, there is a marked transition from modeling simple systems to complex mass service networks. In addition, we conclude that the complex architecture of modern economic systems opens up a wide research field for finding a methodology for assessing the dependence of the enterprise performance on the effect of optimization provided by using the provisions of mass service theory. This statement can be the basis for future research.

Mechanisms of metal wettability transition and fabrication of durable superwetting/superhydrophilic metal surfaces

Maintaining superhydrophilicity on metal surfaces is challenging due to the inevitable surface adsorption of airborne organics after exposure to ambient air. In this study, we aim to elucidate the mechanisms underlying the persistence of surface superhydrophilicity and propose a technique for the preparation of durable superwetting/superhydrophilic metal surfaces. The effects of atmospheric organic properties, including the type of functional groups and the length of the carbon chain, on the rate of wettability transition and the final surface wettability after the surface adsorption are first investigated. Molecular dynamics simulation is used to explain why long-chain organics can lead to more marked wettability transitions. The liquid wetting and organic diffusion on textured surfaces are then analyzed, which proves that conventional surface structures with only single-scale structural features are challenging to achieve long-lasting superhydrophilicity. Finally, an in-situ laser deposition technique is proposed to fabricate micro-nano composite porous structures, in which the microstructures promote liquid wetting and the nanostructures inhibit organic diffusion. The prepared surfaces exhibited a 54-fold enhancement in the duration of surface superhydrophilicity compared to conventional nanostructures. Our results help to understand the mechanisms of durable superhydrophilicity, which are beneficial for the practical applications of superwetting/superhydrophilic surfaces.

Numerical simulation of MHD on sudden expansion duct under strong transverse magnetic field

This research delves into the analysis of quasi-two-dimensional flow dynamics in liquid metal confined within a sudden expansion duct, subjected to a strong magnetic field. Utilizing numerical simulations derived from the SM82 model, the study concentrates on examining the magnetohydrodynamic (MHD) responses across a defined range of parameters. These simulations were conducted maintaining a constant Reynolds number (Re), while systematically varying the Hartmann number (Ha) across a spectrum of values [1000, 2000, 5000, 10000, 15000, 20000] to enable a thorough exploration of the magnetic fields influence on the flow dynamics. The outcomes of this study reveal a marked transition in flow behavior corresponding with the escalation in magnetic field strength. Notably, as the magnetic field intensifies, the flow undergoes a transformation from a state of instability to stability. This shift is predominantly characterized by a diminution, followed by a complete cessation, of shear vortex shedding. Additionally, beyond a Ha of 5000 and at a longitudinal position of x = 6, both the velocity and pressure profiles begin to exhibit near-identical and symmetric characteristics. Post the Ha exceeding 1000, the vortex profile demonstrates symmetry about the y=0 axis. These observations significantly enhance the comprehension of MHD fluid dynamics under quasi-two-dimensional conditions.

Color and multi-band imaging of a cavity-based flameholder in supersonic flow

Utilizing time-resolved CH*/C2* and multi-angle color flame imaging recorded at 1 kHz/22.5 kHz frequencies, this study investigates the dynamics and stabilization of supersonic flames in a cavity flameholder combustor at Mach 2, with ethylene fuel and air. A stagnation pressure of 289 kPa was used for the stable cavity burning experiments with fuel flow rates of 30, 60, and 90 slpm and 483 kPa for ignition transient experiments with fuel flow rates of 55 and 90 slpm, injecting fuel at the closeout ramp. The stagnation temperature was 597 K. Chemiluminescence analysis focused on the equivalence ratio (ER) and combustion intensity, while a fiber-based endoscope captured color flame image, informing on premixedness, flame structure, and flame surface density. Results from transient ignition showed that a progression from lean to stoichiometric, and ultimately to fuel-rich conditions was observed, with marked transitions occurring along the cavity floor. High-intensity CH* regions were consistently associated with fuel-rich zones. Digital flame coloration discrimination (DFCD) analysis provided insights into the mixing efficiency, affecting the flame color and structure. Despite reduced fuel flow rates significantly altering flame characteristics, such as thickness and the persistence of a 'W' flame structure, the shear layer remained a focal point for optimal combustion conditions. The study demonstrated that the shear layer's intense turbulent mixing is crucial for flame stability and structure, with chemiluminescence surface density (CSD) profiles suggesting balanced combustion at 60 and 90 slpm flow rates. However, an asymmetry of CSD at 30 slpm indicated a shift towards fuel-rich conditions at the burning surface, indicating potential instability and elevated blowout.

Protestant Church Strategy in Building Spiritual Identity for Generation Alpha

This research aims to explain Protestant Church strategy in building Christian identity for Generation Alpha (Gen Alpha) amidst the adverse effects of globalization. Currently, the generation is navigating the complex terrain of a postmodern era characterized by the pervasive dissemination of concepts such as skepticism, subjectivism, and relativism. Gen Alpha has experienced a profound shift in cultural values, with a marked transition from religiosity to secularity. Consequently, Church must direct its attention towards the ideological and spiritual well-being of the generation. The influence of distortionary forces on the perception of reality is a matter of concern, stemming from various sources such as peers in the community, the educational system, social media, and the vast expanse of the Internet. The result show that Gen Alpha has been raised in the context of post-Christian and post-Church cultural environments. In this research, a qualitative research approach is used, predominantly through an extensive review of pertinent literature. The examination commences with an in-depth exploration of Gen Alpha and the formation of spiritual identity. Subsequently, the strategic initiatives conducted by Protestant Church are examined and the initiatives include worship services, fatherly mentorship, and cultivating a strong Christian identity. The conclusion shows the collaborative efforts of Church with the pastoral team, in the construction of its ministry. This is characterized by the implementation of transpersonal actions, the guiding of healing initiatives for the needs of families, and the cultivation of personalized spiritual practices. An important component of the comprehensive strategy includes the training and education of fathers to assume a central role in building the spiritual development of children. Furthermore, Church values the spiritual building of children aged between 4 and 14 years to fortify Christian identity.

Excitation lifetime extracted from electron–photon (EELS-CL) nanosecond-scale temporal coincidences

Electron–photon temporal correlations in electron energy loss spectroscopy (EELS) and cathodoluminescence (CL) spectroscopies have recently been used to measure the relative quantum efficiency of materials. This combined spectroscopy, named cathodoluminescence excitation (CLE) spectroscopy, allows for the identification of excitation and decay channels, which are hidden in average measurements. Here, we demonstrate that CLE can also be used to measure excitations' decay time. In addition, the decay time as a function of the excitation energy is measured, as the energy for each electron–photon pair is probed. We used two well-known insulating materials to characterize this technique, nanodiamonds with NV0 defects and hexagonal boron nitride (h-BN) with 4.1 eV defects. Both also exhibit marked transition radiations, whose extremely short decay times can be used to characterize the instrumental response function. It is found to be typically 2 ns, in agreement with the expected limit of the EELS detector temporal resolution. The measured lifetimes of NV0 centers in diamond nanoparticles (20–40 ns) and 4.1 eV defect in h-BN flakes (<2 ns) match those reported previously.

The industrial landscape of Russian pharmaceutical industry in 2010-2018

The article presents interim results of large-scale experiment on organization of pharmaceutical clusters in Russia in the 2010s. For the pharmaceutical industry, organization of clusters marked transition from spontaneous market to development of technological production complexes with full cycle of development, testing and production of medications. For the first time such first "star clusters" as the Kaluga, Yaroslavl and St. Petersburg and "Northern" pharmaceutical clusters are described, including their nascence, institutional formation and encountered problems.

Numerical study of blast wave propagation through granular materials subjected to buried blasts

Blast wave propagation in dry sand subjected to a buried charge is numerically investigated using a charge-sand stratified configuration wherein the mass ratio between sand and charge (M/C) spans over two decades. The detonation of the central charge and the sand dynamics are modeled by the FEM-DEM method. The findings reveal the pressure-profile associated with the blast wave undergoes marked shape transition as the expansion fans catch up with the incident blast wave. The blast propagation and the associated pressure-profiles depend on the coupling between the sand and the detonation products in the central gas pocket which is in turn influenced by a variety of structural parameters. Specifically, as the M/C increases from 21 to 436, the average velocity of the blast wave decreases by 22.2%. Furthermore, a blast compaction model of sand is proposed to account for the coupling effect and justify the influences arising from key-structural parameters.

Abrupt change in tropical Pacific climate mean state during the Little Ice Age

The mean state of the tropical Pacific ocean-atmosphere climate, in particular its east-west asymmetry, has profound consequences for regional climates and for the El Niño/Southern Oscillation variability. Here we present a new high-resolution paleohydrological record using the stable-hydrogen-isotopic composition of terrestrial-lipid biomarkers (δDwax) from a 1,400-year-old lake sedimentary sequence from northern Philippines. Results show a dramatic and abrupt increase in δDwax values around 1630 AD with sustained high values until around 1900 AD. We interpret this change as a shift to significantly drier conditions in the western tropical Pacific during the second half of the Little Ice Age as a result of a change in tropical Pacific mean state tied to zonal sea surface temperature (SST) gradients. Our findings highlight the prominent role of abrupt shifts in zonal SST gradients on multidecadal to multicentennial timescales in shaping the tropical Pacific hydrology of the last millennium, and demonstrate that a marked transition in the tropical Pacific mean state can occur within a period of a few decades.

Patterns in transitional shear turbulence. Part 2. Emergence and optimal wavelength

Low Reynolds number turbulence in wall-bounded shear flows en route to laminar flow takes the form of oblique, spatially intermittent turbulent structures. In plane Couette flow, these emerge from uniform turbulence via a spatio-temporal intermittent process in which localised quasi-laminar gaps randomly nucleate and disappear. For slightly lower Reynolds numbers, spatially periodic and approximately stationary turbulent–laminar patterns predominate. The statistics of quasi-laminar regions, including the distributions of space and time scales and their Reynolds-number dependence, are analysed. A smooth, but marked transition is observed between uniform turbulence and flow with intermittent quasi-laminar gaps, whereas the transition from gaps to regular patterns is more gradual. Wavelength selection in these patterns is analysed via numerical simulations in oblique domains of various sizes. Via lifetime measurements in minimal domains, and a wavelet-based analysis of wavelength predominance in a large domain, we quantify the existence and nonlinear stability of a pattern as a function of wavelength and Reynolds number. We report that the preferred wavelength maximises the energy and dissipation of the large-scale flow along laminar–turbulent interfaces. This optimal behaviour is due primarily to the advective nature of the large-scale flow, with turbulent fluctuations playing only a secondary role.

Long-term changes in macroinvertebrate communities across high-latitude streams.

Long-term records of benthic macroinvertebrates in high-latitude streams are essential for understanding climatic changes, including extreme events (e.g. floods). Data extending over multiple decades are typically scarce. Here, we investigated macroinvertebrate community structural change (including alpha and beta diversity and gain and loss of species) over 22 years (1994-2016) in 10 stream systems across Denali National Park (Alaska, USA) in relation to climatological and meteorological drivers (e.g. air temperature, snowpack depth, precipitation). We hypothesised that increases in air temperature and reduced snowpack depth, due to climatic change, would reduce beta and gamma diversity but increase alpha diversity. Findings showed temporal trends in alpha diversity were variable across streams, with oscillating patterns in many snowmelt- and rainfall runoff-fed streams linked to climatic variation (temperature and precipitation), but increased over time in several streams supported by a mixture of water sources, including more stable groundwater-fed streams. Beta-diversity over the time series was highly variable, yet marked transitions were observed in response to extreme snowpack accumulation (1999-2000), where species loss drove turnover. Gamma diversity did not significantly increase or decrease over time. Investigating trends in individual taxa, several taxa were lost and gained during a relative constrained time period (2000-2006), likely in response to climatic variability and significant shifts in instream environmental conditions. Findings demonstrate the importance of long-term biological studies in stream ecosystems and highlight the vulnerability of high-latitude streams to climate change.