Temperature Shift Research Articles

Corrections of Electron–Phonon Coupling for Second‐Order Structural Phase Transitions

Structural phase transitions are accompanied by a movement of one nucleus (or a few) in the crystallographic unit cell. If the nucleus movement is continuous, a second‐order phase transition without latent heat results, whereas an abrupt nucleus displacement indicates a first‐order phase transition with accompanying latent heat. Herein, a Hamiltonian including electron–phonon coupling (EPC) as proposed by Kristoffel and Konsel is taken. Contrary to their treatment, both the kinetic energy of the nucleus and its position are treated. The interaction of the many‐electron system with the single nucleus is taken into account by the Born–Oppenheimer approximation and perturbative expressions for the free energies are derived. The nuclei corrections due to the entangled electrons are found to be minor, but highlight the importance of the symmetry breaking at low temperature. Furthermore the free energy for a canonical ensemble is computed, whereas Kristoffel and Konsel use a grand canonical ensemble, which allows to derive more stringent bounds on the free energy. For the zero‐order nucleus correction, the shift of the phase transition temperature by evaluating the free energy is deduced.

Observation of TLIESST above Liquid Nitrogen Temperature and Disclosure of Hidden Hysteresis in Multiresponsive Hofmann-type Coordination Polymers.

Photoresponsive spin-crossover (SCO) molecules are an important class of bistable magnetic molecules with intriguing potential in device applications. The light-induced excited spin state trapping (LIESST) and the combined application of light and temperature can provide access to the metastable region of the SCO profile. The primary obstacle in utilizing light stimuli is the manifestation of light-induced trappings at extremely low temperatures. Herein, we report two novel multiresponsive 2D Hofmann-type coordination polymers exhibiting light-induced excited spin state trapping above liquid nitrogen temperature (TLIESST = 82 and 81 K). Stimulating the samples in conjugation with light and temperature successfully unveils hysteresis, which is otherwise concealed. Apart from light and temperature, we found that the SCO phenomenon is also responsive to external hydrostatic pressure and exhibits modulation of the hysteresis width and transition temperature shifts with changes in pressure.

Research on the mechanism of natural antibacterial properties of Calotropis gigantea fiber

This research explores the antibacterial mechanism of Calotropis gigantea (CG) fiber through systematic antimicrobial testing and microstructural characterizations on different types of dried CG fibers. Different temperatures and light exposure times were employed to prepare a series of fiber samples. Standard antimicrobial tests were conducted, revealing that both light exposure time and drying temperature significantly influenced the fiber's antibacterial properties against Escherichia coli. Prolonged light exposure time and drying temperatures notably suppressed the antibacterial efficacy. Chemical composition, surface morphology, and thermal stability were further investigated using various techniques, including laser microscopy, Raman, FTIR, and X-ray photoelectron spectroscopies, as well as thermogravimetric-differential thermal analysis. The results revealed a minor role of surface profile and lignin in the variation of antibacterial properties of CG fiber, which should mainly be associated with the alteration of flavonoids, despite the presence of distinct mass losses and decomposition temperature shifts after fiber drying. This study not only unveils and confirms the resource and mechanism of the antimicrobial activity of Calotropis gigantea fiber but also provides insights to guide future optimization of processes and control of microstructure. These findings hold promise for the development of Calotropis gigantea fiber applications in antibacterial products.

Thermally tuned on-chip optical memory

Phase-change materials, known as Chalcogenide alloys, are a promising alternative to traditional random-access memory. They possess characteristics that are particularly beneficial for non-volatile storage applications. The features of the Phase change material Ge-Sb-Te alloy (GST) used for substrate-integrated optical memory include scaling, quick switching times, minimal switching energy, and exceptional thermal stability. The material has two tuneable states, amorphous and crystalline, with the amorphous layer for loading data optically. In contrast, the crystalline state holds the data longer without significant loss. The study designed a classic thermally tuned optical memory on a silicon substrate. It demonstrated a dependency of lattice structure on external voltage and revealed a large storage capacity for information in the form of an optical signal. The heat transport simulation utilized the Heat Transport (HEAT) solver of the Finite Element Eigenmode (FEEM) solver. At the same time, the optical response analysis involved the Finite Difference Time Domain (FDTD) solver of Lumerical. The proposed structure exhibits a memory-switching phenomenon when a temperature shift of about 60 °C from room temperature is induced by a change in the external voltage of 147 mV. These findings have substantial implications for non-volatile storage memory development, providing a potential solution for high-capacity, low-energy data storage.

Rho-dependent transcriptional switches regulate the bacterial response to cold shock

Binding of the bacterial Rho helicase to nascent transcripts triggers Rho-dependent transcription termination (RDTT) in response to cellular signals that modulate mRNA structure and accessibility of Rho utilization (Rut) sites. Despite the impact of temperature on RNA structure, RDTT was never linked to the bacterial response to temperature shifts. We show that Rho is a central player in the cold-shock response (CSR), challenging the current view that CSR is primarily a posttranscriptional program. We identify Rut sites in 5'-untranslated regions of key CSR genes/operons (cspA, cspB, cspG, and nsrR-rnr-yjfHI) that trigger premature RDTT at 37°C but not at 15°C. High concentrations of RNA chaperone CspA or nucleotide changes in the cspA mRNA leader reduce RDTT efficiency, revealing how RNA restructuring directs Rho to activate CSR genes during the cold shock and to silence them during cold acclimation. These findings establish a paradigm for how RNA thermosensors can modulate gene expression.

Unveiling pepper immunity's robustness to temperature shifts: insights for empowering future crops.

Boosting plant immunity is an effective alternative to pesticides. However, environmental variations, accentuated by climate change, can compromise immunity. The robustness of a trait corresponds to the absence (or low level) of variation in that trait in the face of an environmental change. Here, we examined two types of robustness, robustness of immunity mean and robustness of immunity variation, and proposed nine quantitative robustness estimators. We characterized the immunity of a set of accessions representative of the natural diversity of pepper (Capsicum annuum L.), to two major pathogens: the oomycete Phytophthora capsici Leon. and potato virus Y. For each pathogen, we measured the immunity of accessions in two contrasting environments in terms of temperature. For each type of robustness and each pathogen, the impact of temperature change on immunity varied between accessions. The robustness estimators proved to be complementary and differed in terms of heritability and ability to discriminate accessions. A positive and significant correlation was observed between immunity and robustness. There was no significant relationship between the robustness of immunity to the two pathogens, but some accessions showed high immunity and robustness against both pathogens. These results justify the need to consider both immunity and robustness to environmental variations in order to select varieties adapted to current and future climate conditions. Phenotypic robustness should also be considered when assessing the "value of sustainable cultivation and use" of future plant varieties, particularly during the application process for protection rights granted from the European Community Plant Variety Office.

Correlation of structural and magnetic properties of RFeO3 ( R=Dy,Lu )

In orthoferrites the rare-earth (R) ion has a big impact on structural and magnetic properties; in particular, the ionic size influences the octahedral tilt and the R3+−Fe3+ interaction modifies properties like the spin reorientation. Growth-induced strain in thin films is another means to modify materials properties since the sign of strain affects the bond length and therefore directly the orbital interaction. Our study focuses on epitaxially grown (010)-oriented DyFeO3 and LuFeO3 thin films, thereby investigating the impact of compressive lattice strain on the magnetically active Dy3+ and magnetically inactive Lu3+ compared to uniaxially strained single-crystal DyFeO3. The DyFeO3 films exhibits a shift of more than 20 K in spin-reorientation temperatures, maintain the antiferromagnetic Γ4 phase of the Fe lattice below the spin reorientation, and show double-step hysteresis loops for both in-plane directions between 5 and 390 K. This is the signature of an Fe-spin-induced ferromagnetic Dy3+ lattice above the Néel temperature of the Dy. The observed shift in the film spin reorientation temperatures vs lattice strain is in good agreement with isostatic single-crystal neutron diffraction experiments with a rate of 2 K/kbar. Published by the American Physical Society 2024

Utilizing Thermal Shift Assay to Probe Substrate Binding to Selenoprotein O.

Defining the biological importance of proteins with unknown functions poses a significant obstacle in understanding cellular processes. Although bioinformatic and structural predictions have contributed to the study of unknown proteins, in vitro experimental validations are often hampered by the optimal conditions and cofactors required for biochemical activity. Cofactor binding is not only essential for the activity of some enzymes but may also enhance the thermal stability of the protein. One practical application of this phenomenon lies in utilizing the change in thermal stability, as measured by alterations in the protein's melting temperature, to probe ligand binding. Thermal shift assay (TSA) can be used to analyze the binding of different ligands to the protein of interest or find a stabilizing condition to perform experiments such as X-ray crystallography. Here we will describe a protocol for TSA utilizing the pseudokinase, Selenoprotein O (SelO), for a simple and high-throughput method for testing metal and nucleotide binding. In contrast to canonical kinases, SelO binds ATP in an inverted orientation to catalyze the transfer of AMP to the hydroxyl side chains of proteins in a posttranslational modification known as protein AMPylation. By leveraging the shift in the melting temperatures, we provide crucial insights into the molecular interactions underlying SelO function.

Synergistic rescue of temperature-sensitive p53 mutants by hypothermia and arsenic trioxide.

The p53 tumor suppressor is inactivated by mutations in about 50% of tumors. Rescuing the transcriptional function of mutant p53 has potential therapeutic benefits. Approximately 15% of p53 mutants are temperature sensitive (TS) and regain maximal activity at 32°C. Proof of concept study showed that induction of 32°C hypothermia in mice restored TS mutant p53 activity and inhibited tumor growth. However, 32°C is the lower limit of therapeutic hypothermia procedures for humans. Higher temperatures are preferable but result in suboptimal TS p53 activation. Recently, arsenic trioxide (ATO) was shown to rescue the conformation of p53 structural mutants by stabilizing the DNA binding domain. We examined the responses of 17 frequently observed p53 TS mutants to functional rescue by temperature shift and ATO. The results showed that ATO only rescued mild p53 TS mutants with high basal activity at 37°C. Mild TS mutants showed a common feature of regaining significant activity at the semi-permissive temperature of 35°C and could be further stimulated by ATO at 35°C. TS p53 rescue by ATO was antagonized by the cellular redox mechanism and was rapidly reversible. Inhibition of glutathione (GSH) biosynthesis enhanced ATO rescue efficiency and sustained p53 activity after ATO washout. The results suggest that mild TS p53 mutants are uniquely responsive to functional rescue by ATO due to small thermostability deficits and inherent potential to regain active conformation. Combining mild hypothermia and ATO may provide an effective and safe procedure for targeting tumors with p53 TS mutations.

Synergistic effect of TiO2 nanoparticles and poly (ethylene-co-vinyl acetate) on the morphology and crystallization behavior of polylactic acid

The impact of adding ethylene vinyl acetate copolymer (EVA 80) and 1 wt% TiO2 nanoparticles on the morphology and crystallization behavior of poly(lactic acid) blends was investigated using DSC, SEM, and POM. Thermal analysis revealed the enhancement of crystallinity of PLA in the presence of TiO2 and higher EVA 80 content in the blend. The PLA and EVA 80 components showed compatibility, as evidenced by the shift of the glass transition temperatures of the PLA phase in the blend to lower values compared to neat PLA. The lower temperature shift of the cold crystallization of the PLA and the formation of the small spherulites of the PLA in the blends indicated that the EVA 80 and TiO2 act as a nucleating agent for crystallization. The non-isothermal crystallization parameters of the composites were evaluated using Avrami's modified model, the MO approach, and Friedman’s isoconversional method. The Avrami’s modified rate constant (K) and the effective activation energy values significantly increased with the incorporation of EVA 80 and TiO2 nanoparticles. Furthermore, the thermogravimetric analysis (TGA) showed improved thermal stability of PLA by adding EVA 80 and TiO2.

Climate change is associated with higher phytoplankton biomass and longer blooms in the West Antarctic Peninsula

The Antarctic Peninsula (West Antarctica) marine ecosystem has undergone substantial changes due to climate-induced shifts in atmospheric and oceanic temperatures since the 1950s. Using 25 years of satellite data (1998-2022), this study presents evidence that phytoplankton biomass and bloom phenology in the West Antarctic Peninsula are significantly changing as a response to anthropogenic climate change. Enhanced phytoplankton biomass was observed along the West Antarctic Peninsula, particularly in the early austral autumn, resulting in longer blooms. Long-term sea ice decline was identified as the main driver enabling phytoplankton growth in early spring and autumn, in parallel with a recent intensification of the Southern Annular Mode (2010-ongoing), which was observed to influence regional variability. Our findings contribute to the understanding of the complex interplay between environmental changes and phytoplankton responses in this climatically key region of the Southern Ocean and raise important questions regarding the far-reaching consequences that these ecological changes may have on global carbon sequestration and Antarctic food webs in the future.

Response of wild aquatic insect communities to thermal variation through comparative landscape transcriptomics.

Fluctuations in temperature are recognized as a potent driver of selection pressure, fostering genomic variations that are crucial for the adaptation and survival of organisms under selection. Notably, water temperature is a pivotal factor influencing aquatic organism persistence. By comprehending how aquatic organisms respond to shifts in water temperature, we can understand their potential physiological adaptations to environmental change in one or multiple species. This, in turn, contributes to the formulation of biologically relevant guidelines for the landscape scale transcriptome profile of organisms in lotic systems. Here, we investigated the distinct responses of seven stream stonefly species, collected from four geographical regions across Japan, to variations in temperature, including atmospheric and water temperatures. We achieved this by assessing the differences in gene expression through RNA-sequencing within individual species and exploring the patterns of community-genes among different species. We identified 735 genes that exhibited differential expressions across the temperature gradient. Remarkably, the community displayed expression levels differences of respiration and metabolic genes. Additionally, the diversity in molecular functions appeared to be linked to spatial variation, with water temperature differences potentially contributing to the overall functional diversity of genes. We found 22 community-genes with consistent expression patterns among species in response to water temperature variations. These genes related to respiration, metabolism and development exhibited a clear gradient providing robust evidence of divergent adaptive responses to water temperature. Our findings underscore the differential adaptation of stonefly species to local environmental conditions, suggesting that shared responses in gene expression may occur across multiple species under similar environmental conditions. This study emphasizes the significance of considering various species when assessing the impacts of environmental changes on aquatic insect communities and understanding potential mechanisms to cope with such changes.

Influence of chalcopyrite nanoplatelets on nematic phases of bend-shaped dimeric molecules: Phase diagram, birefringence, and reorientation transition

We investigated the influence of chalcopyrite (CuFeS2) nanoplatelets on the ordering of uniform and twist-bend nematic phases of achiral bend-shaped dimers, employing polarized optical microscopy, optical and electro-optical measurements. Specifically, aliphatic amine surface-functionalized hydrophobic chalcopyrite nanoplatelets were synthesized and characterized by XRD, TEM, and IR-vis-UV spectroscopy. Nanocomposites of the liquid crystal compound 1”,9”-bis(4-cyanobiphenyl-4'-yl)nonane (CB9CB) with the nanoplatelets were prepared. The study encompasses an assessment of the thermodynamic stability of the nanocomposites, constructing the corresponding phase diagram as a function of temperature and nanoplatelet mass fraction. Large phase temperature shifts were observed for minute mass fractions of NPs. Birefringence measurements were performed to investigate the orientational order parameter and the conical tilt angle's dependence on the mass fraction of the nanoplatelets and the temperature. Additionally, we measured a Fréedericksz-like reorientation transition voltage threshold and switching times as functions of the mass fraction and temperature. A huge increase of the voltage threshold was measured in the twist-bend nematic phase. The dependence of the viscoelastic coefficient ζ on NPls' mass fraction was investigated. The splay elastic constant of the helicoidal structure was estimated, using a coarse grain approximation, to be two orders of magnitude higher than in the uniform nematic phase. Finally, in the twist-bend nematic phase, the impact of temperature and nanoplatelets mass fraction on the hysteresis loop of the reorientation transition was investigated.

Investigating Mountain Watershed Headwater‐To‐Groundwater Connections, Water Sources, and Storage Selection Behavior With Dynamic‐Flux Particle Tracking

AbstractClimate change will impact mountain watershed streamflow both directly—with changing precipitation amounts and variability—and indirectly—through temperature shifts altering snowpack, melt, and evapotranspiration. To understand how these complex processes will affect ecosystem functioning and water resources, we need tools to distinguish connections between water sources (rain/snowmelt), groundwater storage, and exit fluxes (streamflow/evapotranspiration), and to determine how these connections change seasonally and as climate shifts. Here, we develop novel watershed‐scale approaches to understand water source, storage, and exit flux connections using a dynamic‐flux particle tracking model (EcoSLIM) applied in California's Cosumnes Watershed, which connects the Sierra Nevada and Central Valley. This work develops new visualizations and applications to provide mechanistic understanding that underpins the interpretation of isotopic field data at watershed scales to distinguish sources, flow paths, residence times, and storage selection. In our simulations, streamflow comes primarily from snow‐derived water while evapotranspiration generally comes from rain. Most streamflow starts above 1,000 m while evapotranspiration is sourced relatively evenly across the watershed and is generally younger than streamflow. Modeled streamflow consists primarily of water sourced from precipitation in the previous 5 years but before the current water year, while ET consists primarily of water from precipitation in the current water year. ET, and to a lesser extent streamflow, are both younger than water in groundwater storage. However, snowmelt‐derived streamflow preferentially discharges older water from snow‐derived storage. Dynamic‐flux particle tracking and new approaches presented here enable novel model‐tracer comparisons in large‐scale watersheds to better understand watershed behavior in a changing climate.

A Review on Global Warming

One of the most important environmental issues of our time is global warming, which is primarily caused by human activity. In order to provide a thorough examination of the phenomenon, this review paper will cover its fundamental causes, observed and anticipated effects on the Earth's climate and ecosystems, as well as proposed mitigating measures. The atmospheric emission of greenhouse gases, particularly carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), is the main cause of global warming. The remarkable rise in greenhouse gas concentrations during the past century has been mostly attributed to the burning of fossil fuels, deforestation, industrial operations, and agricultural activities. The effects of global warming are numerous and extensive. Increasing temperatures have sped up the melting of glaciers and polar ice caps, which has raised sea levels and increased the likelihood of coastal flooding. Extreme weather occurrences, such as heatwaves, droughts, and violent storms, have increased in frequency and have a negative effect on agriculture, water supplies, and vulnerable communities. Additionally, as ecosystems experience extraordinary shifts in temperature and precipitation patterns, biodiversity loss and ecosystem disruption are being seen. This paper presents a variety of potential mitigation tactics that could be used to alleviate the problems caused by global warming. Among these include switching to renewable energy sources, improving energy efficiency, putting reforestation and afforestation programmes into action, and applying sustainable agriculture methods. Additionally, international collaboration and policy frameworks are essential for promoting group initiatives. With significant effects on the environment and society, global warming continues to be a top priority. On a local, national, and international level, cooperation is required to address this complicated issue. This review emphasises how crucial it is to comprehend the underlying causes, effects, and mitigation strategies in order to effectively combat global warming and build a sustainable future for future generations

A Cross Sectional Study On Knowledge, Risk Perception and Behavior related to Climate Change Among Students of University of Cyberjaya

Introduction: Climate change refers to long-term shifts in temperatures and weather patterns, primarily driven by human activities. It is crucial to introduce the importance of understanding about climate change and its impacts on both the environment and human well-being worldwide as an integral component of educational curricula within institutions However, there is still lack of research on the knowledge, awareness and behaviour regarding climate change among students in the higher institution in Malaysia. Objectives: The study focuses on assessing the relationship between knowledge, risk perception, and behaviour related to climate change among University of Cyberjaya students. Methodologies: Cross-sectional study with proportionate stratified random sampling was conducted among University of Cyberjaya students using a validated questionnaire that cover sociodemographic characteristics, knowledge, risk perception, and behaviour related to climate change. The data was collected using self-administered questionnaires (Google Form) via online and via physical approach. Data then analyzed with JASP 0.17 software; chi-square was used to determine associations between knowledge and risk perception, knowledge and behaviour, and risk perception and behavior of climate change. A statistical test with a p-value of less than 0.05 considered statistically significant. Results: The results indicate that climate change-related knowledge level among students at the University of Cyberjaya is mostly fair to low, with 29.6% have low knowledge and 36.1% fair knowledge. The risk perception among students is notably high, with 56.4% having a high-level of perception and 43.6% having a low-level perception towards climate change. 63.9% of the students have poor behaviour related to climate change. There is a statistically significant association between the knowledge level of climate change and the risk perception towards climate change among students at the University of Cyberjaya (p-value < 0.05). The association between risk perception and behaviour was found to be statistically significant (P < 0.001). However, the association between knowledge and behaviour towards climate change among students was not statistically significant (P = 0.054). This research provides valuable finding for the decision maker in higher institution to incorporate the understanding about climate change for the effectiveness of current educational approaches and the potential for future improvements.

Temporal temperature shifts govern the population succession of picoeukaryotes and picocyanobacteria in a coastal ecosystem

Picophytoplankton are vital components of the marine microbial food web. Being the smallest in the phytoplankton group, their short life cycles make them excellent bioindicators of environmental conditions. Given this, an investigation was conducted at the Kandla Port ecosystem (Latitude 23º 01' N; Longitude 70º 13' E) in the state of Gujarat, India to assess the response of picophytoplankton community structure to temporal and spatial environmental conditions. The sampling was conducted in July 2015, October-November 2015, and February 2016 at twenty-six stations. The results revealed a wide annual temperature range due to the study site's proximity to the Tropic of Cancer. The salinity ranged up to 40 while the turbulence caused by the macrotides resulted in highly turbid waters, especially during July due to precipitation. The picophytoplankton community was represented by picocyanobacteria (three sub-groups of Synechococcus) and picoeukaryotes (three sub-groups including Cryptophytes). The picocyanobacteria were abundant during the less turbid, warmer October-November period and lower during the cooler February period. The dominant Synechoccocus groups are associated positively with NH4+ and negatively with PO43-. The Cryptophytes were present during the warm and cool periods indicating tolerance to a wide range of temperature, salinity, and light. Their positive correlation with PO43- and NH4+ concentrations during February and October-November, respectively suggests a causal relationship. The picoeukaryotic group dominated the picophytoplankton community during the cooler period (February). The relative importance of the two picophytoplankton groups changed throughout the year exhibiting temporal niche segregation and hence establishing their role as bioindicators of temperature.

Temperature and pressure prediction of offshore high CO2-content associated gas lift and analysis of influencing factors

With the continuous injection of CO2 into the reservoir, a portion of the sequestered CO2 is co-produced with crude oil, resulting in a significant concentration of CO2 in the associated gas. Utilizing high CO2-content associated gas for offshore gas lift operations improves the reutilization of such gas and reduces costs related to sourcing and transporting it. To ensure smooth activation of the gas lift valve, conducting a thorough study on temperature and pressure within the wellbore during the gas lift process is essential. This study developed a dynamic model for calculating the transient temperature and pressure within offshore gas lift wellbores and fitted equations to calculate the physical properties of high CO2-content associated gas for specific compositions. This refinement minimized computational discrepancies arising from fluctuations in physical property parameters. When applying this model to oilfield scenarios, the maximum error observed was 3.83%, which aligned well with the accuracy standards required for oilfield computations. By integrating oilfield production data, this research explored the influence of injection parameters on temperature and pressure dynamics within the gas lift wellbore. The results revealed that variations in injection temperature and pressure had minimal impact on the temperature at the gas lift valve. Yet, they induced significant changes in the pressure at that point. An increase in CO2 concentration within the gas source composition was associated with considerable shifts in temperature and pressure gradients throughout the wellbore. At high mass flow rates, the temperature gradient of the wellbore was notably reduced, while the pressure gradient was significantly enhanced. These research findings provided a theoretical basis for optimizing gas lift operations using high CO2-content associated gas in offshore settings.

Oleic acid-induced changes in the dynamic viscoelastic behavior of poly(methyl methacrylate) polymer film

This study investigates the impact of oleic acid on the dynamic viscoelastic behavior of polymethyl methacrylate (PMMA) polymer films. By incorporating oleic acid as a plasticizer, we aim to enhance the ductility and reduce the brittleness of PMMA. Dynamic mechanical analysis (DMA) was employed to assess changes in viscoelastic properties, revealing significant improvements in the flexibility and energy dissipation capacity of the PMMA films. The addition of oleic acid resulted in a noticeable shift in the glass transition temperature and a reduction in storage modulus, indicating enhanced polymer chain mobility. Raman and infrared spectroscopy confirmed the successful integration of oleic acid, highlighting its interaction with PMMA at the molecular level. Our findings demonstrate that oleic acid is an effective plasticizer for PMMA, providing valuable insights into the design of flexible and durable polymer-based materials for various applications.

Oxygen levels differentially attenuate the structure and diversity of microbial communities in the oceanic oxygen minimal zones

Global change mediated shifts in ocean temperature and circulation patterns, compounded by human activities, are leading to the expansion of marine oxygen minimum zones (OMZs) with concomitant alterations in nutrient and climate-active trace gas cycling. While many studies have reported distinct bacterial communities within OMZs, much of this research compares across depths rather with oxygen status and does not include eukayrotic microbes. Here, we investigated the Bay of Bengal (BoB) OMZ, where low oxygen conditions are persistent, but trace levels of oxygen remain (< 20 μM from 200 to 500 m). As other environmental variables are similar between OMZ and non-OMZ (NOZ) stations, we compared the abundance, diversity, and community composition of several microbial groups (bacterioplankton, Labyrinthulomycetes, and fungi) across oxygen levels. While prokaryote abundance decreased with depth, no significant differences existed across oxygen groups. In contrast, Labyrinthulomycetes abundance was significantly higher in non-OMZ stations but did not change significantly with depth, while fungal abundance was patchy without clear depth or oxygen-related trends. Bacterial and fungal diversity was lower in OMZ stations at 500 m, while Labyrinthulomycetes diversity only showed a depth-related profile, decreasing below the euphotic zone. Surprisingly, previously reported OMZ-associated bacterial taxa were not significantly more abundant at OMZ stations. Furthermore, compared to the bacterioplankton, fewer Labyrinthulomycetes and fungi taxa showed responses to oxygen status. Thus, this research identifies stronger oxygen-level linkages within the bacterioplankton than in the examined microeukaryotes.