Level Fluctuations Research Articles

Effects of time of the day at sampling on CSF and plasma levels of Alzheimer’ disease biomarkers

BackgroundStudies suggest that cerebrospinal fluid (CSF) levels of amyloid-β (Aβ)42 and Aβ40 present a circadian rhythm. However sustained sampling of large volumes of CSF with indwelling intrathecal catheters used in most of these studies might have affected CSF dynamics and thereby confounded the observed fluctuations in the biomarker levels.MethodsWe included 38 individuals with either normal (N = 20) or abnormal (N = 18) CSF Aβ42/Aβ40 levels at baseline. CSF and plasma were collected at two visits separated by an average of 53 days with lumbar punctures and venipunctures performed either in the morning or evening. At the first visit, sample collection was performed in the morning for 17 participants and the order was reversed for the remaining 21 participants. CSF and plasma samples were analyzed for Alzheimer’ disease (AD) biomarkers, including Aβ42, Aβ40, GFAP, NfL p-tau181, p-tau217, p-tau231 and t-tau. CSF samples were also tested using mass spectrometry for 22 synaptic and endo-lysosomal proteins.ResultsCSF Aβ42 (mean difference [MD], 0.21 ng/mL; p = 0.038), CSF Aβ40 (MD, 1.85 ng/mL; p < 0.001), plasma Aβ42 (MD, 1.65 pg/mL; p = 0.002) and plasma Aβ40 (MD, 0.01 ng/mL, p = 0.002) were increased by 4.2-17.0% in evening compared with morning samples. Further, CSF levels of 14 synaptic and endo-lysosomal proteins, including neurogranin and neuronal pentraxin-1, were increased by 4.5-13.3% in the evening samples (MDrange, 0.02-0.56 fmol/µl; p < 0.042). However, no significant differences were found between morning and evening levels for the Aβ42/Aβ40 ratio, different p-tau variants, GFAP and NfL. There were no significant interaction between sampling time and Aβ status for any of the biomarkers, except that CSF t-tau was increased (by 5.74%) in the evening samples compared to the morning samples in Aβ-positive (MD, 16.46 ng/ml; p = 0.009) but not Aβ-negative participants (MD, 1.89 ng/ml; p = 0.47). There were no significant interactions between sampling time and order in which samples were obtained.DiscussionOur findings provide evidence for diurnal fluctuations in Aβ peptide levels, both in CSF and plasma, while CSF and plasma p-tau, GFAP and NfL were unaffected. Importantly, Aβ42/Aβ40 ratio remained unaltered, suggesting that it is more suitable for implementation in clinical workup than individual Aβ peptides. Additionally, we show that CSF levels of many synaptic and endo-lysosomal proteins presented a diurnal rhythm, implying a build-up of neuronal activity markers during the day. These results will guide the development of unified sample collection procedures to avoid effects of diurnal variation for future implementation of AD biomarkers in clinical practice and drug trials.

Operational effects on aquatic carbon dioxide and methane emissions from the Belo Monte hydropower plant in the Xingu River, eastern Amazonia

Operational demands and the natural inflow of water actively drive biweekly fluctuations in water levels in hydropower reservoirs. These daily to weekly fluctuations could have major effects on methane (CH4) and carbon dioxide (CO2) emissions via release of bubbles from reservoir bottom sediments (ebullition) or organic matter inputs, respectively. The impact of transient fluctuations in water levels on GHG emissions is poorly understood and particularly so in tropical run-of-the-river reservoirs. These reservoirs, characterized by high temperatures and availability of labile organic matter, are usually associated with extensive CH4 generation within bottom sediments. The aim of this study is to determine how water level fluctuations resulting from the operation of the Belo Monte hydropower plant on the Xingu River, eastern Amazon River Basin, affect local CO2 and CH4 emissions. Between February and December 2022, we monitored weekly fluxes and water concentrations of CO2 and CH4 in a site on the margin of the Xingu reservoir. Throughout the study period, fluxes of CO2 and CH4 were 118 ± 137 and 3.62 ± 8.47 mmol m−2 d−1 (average ± 1SD) while concentrations were 59 ± 29.77 and 0.30 ± 0.12 μM, respectively. The fluxes and water concentrations of CO2 were clearly correlated with the upstream discharge, and the variation observed was more closely associated with a seasonal pattern than with biweekly fluctuations in water level. However, CH4 fluxes were significantly correlated with biweekly water level fluctuations. The variations observed in CH4 fluxes occurred especially during the high-water season (February–April), when biweekly water level fluctuations were frequent and had higher amplitude, which increased CH4 ebullition. Reducing water level fluctuations during the high-water season could decrease ebullitive pulses and, consequently, total flux of CH4 (TFCH4) in the reservoir margins. This study underscores the critical role of water level fluctuations in near-shore CH4 emissions within tropical reservoirs and highlights significant temporal variability. However, additional research is necessary to understand how these findings can be applied across different spatial scales.

LOWER ORDOVICIAN STROMATOLITES FROM THE KEY MOYERO SECTION (TUNGUSKA SYNECLISE, EASTERN SIBERIA)

Stromatolite bioherms were found in the Lower Ordovician sediments of the Moyero River section (Tunguska syneclise, Eastern Siberia). Their characteristics are considered on the example of their typical build-up and adjacent sediments. It was revealed that the formation of the studied sediments occurred during the development of both bacterial communities (primarily cyanobacteria) and calcareous algae. The presence of remains of calcareous algae Nuia of different preservation in bioclast-oolitic and oolite-bioclastic limestones underlying stromatolite and composing sediments between bioherms was established. It is assumed that the growth of stromatolite bioherms and adjacent sediments was controlled by sea level fluctuations which were reflected in the transgressive-regressive cyclicity and changes of sedimentation conditions.

Characteristic analysis of mold level fluctuation during continuous casting of Ti-bearing IF steel

Mold level fluctuation has always been one of the key factors in slab quality control. Abnormal fluctuations can easily cause slag entrainment and form surface defects of hot-rolled and cold-rolled steel sheets, thus reducing the product qualification rate. In this study, mold level fluctuation data was collected during Ti-bearing Interstitial Free (IF) steel in a stable state for a complete casting sequence in a certain factory. The mold level fluctuation is analyzed using the discrete wavelet transform (DWT) method, and its characteristic values are classified based on frequency. Combined with the corresponding process parameters, the causes were traced during abnormal fluctuation characteristic values. It was found that the formation of abnormal mold level fluctuation mainly comes from two aspects. On the one hand, there are random fluctuations in the low-frequency band, and on the other, there are clustered fluctuations in the relatively high-frequency band. There is always a rising trend in mold liquid levels when there are random abnormal fluctuations in the low-frequency band. There is a delay of approximately 0.1412 s in the feedback of the stopper rod to the mold level fluctuation. The major causes of the low-frequency random fluctuations include variations in the tundish weight, casting speed, and mold width, and the clogs peeling. The clogging of the side hole at the submerged entry nozzle (SEN) is the primary cause of abnormal clustered fluctuations in the high-frequency band. These are certain relationships with clogging, whether it is high-frequency clustered or low-frequency random abnormal fluctuations. Without a doubt, this is a crucial link that limits the slab quality.

Использование данных дистанционного зондирования Земли для анализа межгодовой динамики площади Тениз-Коргалжынских озер

The Teniz-Korgalzhyn lake system has the status of an international Ramsar site and is the most important ornithological center in Central Asia. It includes more than 60 shallow fresh- and salt water bodies among which the largest salt ones are Big and Small Teniz and a group of fresh Korgalzhyn lakes. Fluctuations in water levels there and changes in their area determine the degree of favorable habitat conditions for key ornithological species. A quantitative assessment of the water levels’ interannual dynamics in 2006–2019 was carried out using remote sensing and geoinformation mapping methods. The choice of the methodology to use multispectral data for water surface area study is substantiated. Calculations are made, and a corresponding map of the bodies’ water surface area dynamics is compiled. Four periods with multidirectional dynamics of changes in it were identified. They are caused by both natural and anthropogenic factors and differ in intensity for fresh and salt lakes. Fluctuations of fresh Korgalzhyn ones are mostly associated with natural and climatic impact. Salty Big and Small Teniz are characterized by more significant changes in water surface the area, caused primarily by human activities, including periodic breakthroughs of retaining dams. Maximum deviations towards the increase were noted for fresh ones in 2016–2019, and for saline in 2014–2019. The observed decrease in the total area of the water surface in the period from 2006 to 2013 was mainly associated with the Small and Big Teniz

Algorithmic Failure? The Weimar Triangle as a Subregional Emulation of Global Governance Structures

This article addresses the issue of discontinuity in the context of the multilevel nature of global governance and the relationship between the determinants of continuity and the sustainability of (sub)regional institutional arrangements. The main purpose of the discussion is to better understand continuity disturbances in the Weimar Triangle. These disturbances are expressed not only in fluctuations in the cooperation levels within the Triangle, but also in increasingly long periods of institutional inertia. The study is based on the assumption that the main reason for the disturbances in the continuity of the Weimar Triangle is the suboptimal emulation of the operating algorithms developed in the G7, that is, the sequences of principles, practices, and knowledge that Germany and France had internalized through their long-term socialization in the G7, and then transferred to the subregional level in order to ensure adaptability and receptiveness in the functioning of the Weimar Triangle.

Effects of Vegetation Cover Varying along the Hydrological Gradient on Microbial Community and N-Cycling Gene Abundance in a Plateau Lake Littoral Zone

The lake littoral zone is periodically exposed to water due to water level fluctuations, driving the succession and distribution of littoral vegetation covers, which complexly affect nutrient biogeochemical transformation. However, the combined effects of water level fluctuations and other environmental factors on microbial characteristics and functions at the regional scale remain unclear. In this study, typical vegetation cover types along various water levels were chosen to investigate the effects of water level and vegetation cover on the microbial community and functional genes in the Lake Erhai littoral zone. The results showed that water level fluctuations influenced oxygen and nitrogen compound contents due to oxic–anoxic alternations and intensive material exchange. Meanwhile, vegetation cover affected the organic matter and total nitrogen content through plant residues and root exudation supplying exogenous carbon and nitrogen. Along the hydrological gradient, the high microbial diversity and abundant microbes related to nitrogen cycling were observed in interface sediments. It was attributed to the alternating aerobic–anaerobic environments, which filtered adaptable dominant phyla and genera. The abundances of amoA AOA, nirS, and amx were higher than those of the other genes and were strongly related to flooding days and water content. In conclusion, water level fluctuations and vegetation type jointly affect microbial community structure and nitrogen-related functional genes.

Changes in the Hydrological Regime of the Volga River and Their Influence on Caspian Sea Level Fluctuations

Changes in the Hydrological Regime of the Volga River and Their Influence on Caspian Sea Level Fluctuations

Evidence of lake-level fluctuations during the late Holocene based on diatoms from Lake Vransko, Cres Island (north-central Mediterranean)

An investigation of Lake Vransko, located on the island of Cres in the Adriatic Sea, was performed in order to reconstruct the palaeoenvironmental changes that occurred during the late Holocene, based on diatoms. Fluctuations in the lake level were mostly driven by the intensification of climatic oscillations (wet periods during North Atlantic Oscillation intervals and summer drought during Azores High intervals) and anthropogenic influences (e.g. the extraction of drinking water). The anthropogenic impact of local deforestation is encountered, associated with a peak in phosphorous in the deeper parts of the lake cores. As a consequence of these impacts ten diatom abundance zones (DZs) and the water/sediment interface (WSI) were recorded from the deeper core (CS-51) and two from the shallower (CS-52) core, along with the WSI, based on which an abrupt fluctuation in the level of the lake was interpreted. A dominance of Epithemia adnata in the deeper core, and Gomphonema pumilum in the CS-51, and in the CS-52 indicated a shallow phase connected with the summer drought recorded in the lake. A dominance of Amphora inariensis, Pseudostaurosira spp., Cyclotella spp. and Pantocsekiella ocellata in the rest of the cores indicated deeper, more alkaline lake conditions during the wet periods. The DZs accord with depth variations in Adriatic coastal lakes that are key sites of more extreme recent changes in the local climate.

In Situ Visualizing Carboxylesterase Activity in Type 2 Diabetes Mellitus Using an Activatable Endoplasmic Reticulum Targetable Proximity Labeling Far-Red Fluorescent Probe.

Carboxylesterase (CE), an enzyme widely present in organisms, is involved in various physiological and pathological processes. Changes in the levels of CEs in the liver may predict the presence of type 2 diabetes mellitus (T2DM). Here, a novel dicyanoisophorone (DCI)-based proximity-labeled far-red fluorescent probe DCI2F-Ac with endoplasmic reticulum targeting was proposed for real-time monitoring and imaging of the CEs activity. DCI2F-Ac featured very low cytotoxicity and biotoxicity and was highly selective and sensitive for CEs. Compared with traditional CEs probes, DCI2F-Ac was covalently anchored directly to CEs, thus effectively reducing the loss of in situ fluorescent signals due to diffusion. Through the "on-off" fluorescence signal readout, DCI2F-Ac was able to distinguish cell lines and screen for CEs inhibitors. In terms of endoplasmic reticulum (ER) stress, it was found that thapsigargin (Tg) induced upregulation of CEs levels but not tunicamycin (Tm), which was related to the calcium homeostasis of the ER. DCI2F-Ac could efficiently detect downregulated CEs in the livers of T2DM, and the therapeutic efficacy of metformin, acarbose, and a combination of these two drugs was assessed by tracking the fluctuation of CEs levels. The results showed that combining metformin and acarbose could restore CEs levels to near-normal levels with the best antidiabetic effect. Thus, the DCI2F-Ac probe provides a great opportunity to explore the untapped potential of CEs in liver metabolic disorders and drug efficacy assessment.

The general patterns of water flow in loess slope system and implications for slope geological security

Loess regions face significant challenges in quantifying hydrological processes and assessing geological environmental risks due to the prevalent development of preferential pathways and the limitations of existing monitoring technologies. To advance this knowledge, this study presents an improved electrical resistivity tomography (ERT) device, specifically designed for loess moisture observations. By refining the testing principle, power supply mode, and data collection method within the existing ERT framework, the new device offers unmanned operation, automatic data acquisition, remote transmission, and cost efficiency. It effectively tracks water movement and groundwater level fluctuations across various hydrological conditions, supporting long-term online monitoring of hydrological processes of loess slopes. Through the analysis of monitoring data and classification of 12 observed preferential flow types, water movement in loess systems can be generalized into four general patterns: uniform infiltration, preferential infiltration, inflowing diffusion, and lateral flow. This generalized scheme provides a simplified modeling approach for other researchers to quantify slope hydrodynamics and to assess geological safety risks involving preferential flow. Based on these insights and field investigations, a conceptual framework is proposed to elucidate the seepage-structure synergistic initiating mechanism of loess landslides. This framework suggests that water entry and movement patterns within the slope depend on the slope geological structure related to preferential pathways and the prevailing hydrological scenarios. Landslide occurs as the result of the progressive failure and reciprocal evolution between the slope hydrological environments and geological structure, which may also pose potential eco-hydrological risks. The outcome advances the development of slope hydrological monitoring technology and enhances the understanding of water movement laws and the associated geological environmental risks in loess slope systems, which is of vital importance to the early warning methods of loess landslides that account for preferential flow and for theoretical modeling of preferential flow in related disciplines.

The effect of lithium variation coefficient on the risk of attack in patients with bipolar disorder: A pilot study.

This study examines the association between the coefficient of variation (%CV) of lithium levels and episode risk and frequency in bipolar patients maintaining serum lithium levels within the therapeutic range. We retrospectively reviewed patients with bipolar disorder under care from 2018 to 2022. Inclusion criteria were at least 2years of follow-up, a minimum of three annual lithium level measurements within the therapeutic range. Patients were categorized based on seizure status. We calculated mean lithium levels, standard deviation (SD), and %CV. The study included 75 patients (patients with-without episodes, 39-36). Demographic data revealed no significant differences. While mean lithium levels showed no significant disparity between groups, SD and %CV were notably higher in patients with episodes (P < .05). ROC analysis demonstrated AUC values of 0.722 (95% CI: 0.607-0.836 P = .001) for %CV and 0.709 (95% CI: 0.593-0.826; P = .002) for SD. The optimal %CV cutoff was 17.39, with 67% sensitivity and 69% specificity. A weak correlation was found between %CV and the number of episodes (P = .001, r = 0.376). The post-hoc power analysis for this study was 0.78. Despite acceptable lithium levels, patients with recent episodes exhibited significant lithium level fluctuations. Integrating %CV with real-time lithium measurements during bipolar disorder follow-up may enhance clinical monitoring and seizure prediction.

Sedimentary Evolution Laws and Main Controlling Factors of the Nenjiang Formation in the Songnan Da’anbei Area, China

Shallow-water deltas serve as a critical area for the exploration and development of terrestrial lacustrine oil and gas reservoirs. Current research on oil and gas exploration and development in China’s terrestrial lacustrine basins primarily focuses on their delta front facies zones. Despite extensive discussions on the sedimentary characteristics of shallow-water deltas by predecessors, there is a lack of comprehensive analysis on the combined effects of dynamic factors such as climate change, lake level fluctuations, and sediment supply. This paper, through a detailed examination of 12 core samples and integrating data from 493 exploratory, appraisal, and development wells in the study area, establishes a stratigraphic correlation framework using well–seismic integration techniques. It identifies two main sedimentary facies types in the southern Da’anbei area of the Songliao Basin: shallow-water deltas and lake facies, which can be further subdivided into four sub-facies and nine microfacies. Two depositional models for the shallow-water deltas of the Southern Songliao Nenjiang Formation are established: a deeper water background with channel-river mouth bar sequences forming the delta front framework and a shallower water background with channel-sheet sand sequences forming the delta front framework. This paper also discusses the controlling effects of paleoclimate, sediment supply, and lake level changes on sedimentary evolution, providing a scientific basis for the exploration of lithologic oil and gas reservoirs in the Nenjiang Formation of the study area and the deployment of horizontal wells.

Spatio-temporal heterogeneity of ecological water level in Poyang Lake, China

Anthropogenic activities and climate change have caused physical and ecological changes in lakes and have aggravated water level fluctuations, which are essential factors to consider for nutrient import, ecological protection, and biodiversity maintenance. Maintaining water levels within a reasonable range is essential for maintaining lake function and ecological health, because ecosystem stability is compromised when water level fluctuations exceed specific thresholds. Thus, the ecological water level (EWL) is an important index for maintaining aquatic habitats and biodiversity. A method for quantifying the EWL of lakes based on hydrological statistical analysis was constructed to bridge the gaps in existing studies, considering both the hydrological alteration and spatio-temporal heterogeneity of water level fluctuations. Taking Poyang Lake as an example, which has recently attracted increasing global attention owing to its water level alterations and subsequent ecological problems, the applicability of the method and rationality of the results were verified. The results indicate that hydrological alteration occurs at the water level of the representative stations, which is jointly affected by climate change and anthropogenic activities in this region. For instance, the construction and operation of the Three Gorges Project affected the water level alteration at Hukou and Xingzi station, and drought further aggravated that of Xingzi station. The calculated EWL of Poyang Lake showed obvious spatio-temporal heterogeneity, which is consistent with the topographic, geographical, and climatic characteristics of the basin. And the rationality of the EWL in this study was verified through literature reviews and satisfiability of characteristic species requirements. The proposed EWL calculation method is simple and feasible with easy data acquisition, strong universality, and broad application prospects, offering a scientific basis and quantitative reference for water resource management and lake ecosystem protection.

Physical Model Test of Deformation Self-Adaptive Mechanism of Landslide Mass

Reservoir impoundment induces a large amount of cumulative deformation of landslide body, leading to damage to the geological environment. Due to many yearly cycles of reservoir water fluctuation, the cumulative deformation of landslides tends to be stable, showing a self-adaptive deformation phenomenon. The study of the self-adaptive deformation mechanism is very important for evaluating landslide stability and achieving the safe operation of hydropower stations. To study the mechanism of self-adaptive deformation, two sets of physical models were used to monitor the groundwater, earth pressure, and cumulative deformation of landslide under periodic fluctuations of the reservoir water level. The results showed that the soil consolidation compaction, release of sliding stress, and increase in permeability are the three main factors of the self-adaptive deformation of landslide accumulation. The overall permeability decreased first and then increased, the front permeability increased greatly, and the middle and rear permeability decreased. The main factors that affected the permeability change were deformation and seepage force.

Decoding uranium variation over the Indian peninsula through leveraging standardized precipitation evapotranspiration indices and groundwater level fluctuations

The present study aims to predict the concentration of uranium (U) in groundwater in India by utilizing water quantity indicators, such as Standardised Precipitation Index (SPI), Standardised Precipitation Evapotranspiration Index (SPEI), and Gravity Recovery and Climate Experiment (GRACE) based groundwater levels. The study adopts a multi-scale approach, ranging from state-level to agroclimatic zones. The findings indicate that the highest levels of U (101–500 μg.L−1), which surpass the World Health Organization (WHO) prescribed limit of 30 μg.L−1 for drinking water, are primarily concentrated in India's plateau and hills regions. The GRACE data map portrays a downward trend in groundwater levels throughout India, with the mid-Gangetic plains experiencing the most significant decline. The meteorological aspect of the study, as indicated by SPI and SPEI, reveals that the plateau and hills region is experiencing a decline in rainfall. The SPEI further underscores the grim picture of decreasing precipitation in northern India. Additionally, the study employs cluster analysis to cluster states according to the division of agro-climatic zones. Lastly, the study employs a random forest algorithm to assess the relative importance of each predictor and predict U concentration under the trinity of precipitation, extraction, and evaporation. The most significant contribution of this work is to identify the hotspots in India that require the most attention in terms of U toxicity owing to groundwater decline. Overall, this study highlights the need for immediate attention to mitigate the adverse impacts of U contamination and aims at sensitizing the stakeholders towards the compelling need to fulfil SDG-3 (health aspects due to U hazard) and SDG-6 (groundwater over-exploitation and deteriorating water quality).

Regulating flow to maximize riverine nitrogen removal by riparian zones downstream of reservoirs

Flood waves generated by reservoir discharge play a crucial role in the potential for riparian denitrification downstream. The efficiency of nitrogen (N) removal from river water by riparian zones is typically enhanced with greater wave amplitude (A) and duration (T). However, a knowledge gap exists with respect to the impact of flood waves on N removal when considering a fixed-value integral over time of flood waves (IOFW). This study explored N transport and transformation in the riparian zone downstream of the dammed Inbuk River, Korea under various wave conditions with a fixed IOFW. The results revealed a logarithmic enhancement in solute infiltration into the riverbank with an increasing wave amplitude/duration ratio (A/T ratio). The solute residence time within the riparian zone displays an initial increase followed by a decrease with the increment in the A/T ratio. We identified a threshold for the wave A/T ratio that maximizes riverine N removal by the riparian zone, a phenomenon observed across various dammed rivers. Our findings indicated that riparian denitrification is reaction time-limited when the wave A/T ratio exceeds the threshold; contrarily, it becomes transport capacity-limited. Additionally, we observed a significant relationship between the net nitrate removal and the return/infiltration time ratio of water (r2 = 0.93, p < 0.05). The research results contribute to a better understanding of the impact of water level fluctuations on the N cycle in riparian zones, and provide valuable insights for developing sustainable reservoir operation strategies.

Accuracy of FreeStyle Libre flash glucose monitoring in patients with type 2 diabetes who migrated from highlands to plains

BACKGROUND The FreeStyle Libre flash glucose monitoring (FGM) system entered the Chinese market in 2017 to complement the self-monitoring of blood glucose. Due to its increased usage in clinics, the number of studies investigating its accuracy has increased. However, its accuracy has not been investigated in highland popu-lations in China. AIM To evaluate measurements recorded using the FreeStyle Libre FGM system compared with capillary blood glucose measured using the enzyme electrode method in patients with type 2 diabetes (T2D) who had migrated within 3 mo from highlands to plains. METHODS Overall, 68 patients with T2D, selected from those who had recently migrated from highlands to plains (within 3 mo), were hospitalized at the Department of Endocrinology from August to October 2017 and underwent continuous glucose monitoring (CGM) with the FreeStyle Libre FGM system for 14 d. Throughout the study period, fingertip capillary blood glucose was measured daily using the enzyme electrode method (Super GL, China), and blood glucose levels were read from the scanning probe during fasting and 2 h after all three meals. Moreover, the time interval between reading the data from the scanning probe and collecting fingertip capillary blood was controlled to &lt; 5 min. The accuracy of the FGM system was evaluated according to the CGM guidelines. Subsequently, the factors influencing the mean absolute relative difference (MARD) of this system were analyzed by a multiple linear regression method. RESULTS Pearson’s correlation analysis showed that the fingertip and scanned glucose levels were positively correlated (R = 0.86, P = 0.00). The aggregated MARD of scanned glucose was 14.28 ± 13.40%. Parker's error analysis showed that 99.30% of the data pairs were located in areas A and B. According to the probe wear time of the FreeStyle Libre FGM system, MARD1 d and MARD2–14 d were 16.55% and 14.35%, respectively (t = 1.23, P = 0.22). Multiple stepwise regression analysis showed that MARD did not correlate with blood glucose when the largest amplitude of glycemic excursion (LAGE) was &lt; 5.80 mmol/L but negatively correlated with blood glucose when the LAGE was ≥ 5.80 mmol/L. CONCLUSION The FreeStyle Libre FGM system has good accuracy in patients with T2D who had recently migrated from highlands to plains. This system might be ideal for avoiding the effects of high hematocrit on blood glucose monitoring in populations that recently migrated to plains. MARD is mainly influenced by glucose levels and fluctuations, and the accuracy of the system is higher when the blood glucose fluctuation is small. In case of higher blood glucose level fluctuations, deviation in the scanned glucose levels is the highest at extremely low blood glucose levels.

Deformation Monitoring Based on SBAS-InSAR and Leveling Measurement: A Case Study of the Jing-Mi Diversion Canal in China.

The Jing-Mi Diversion Canal is a large-scale water diversion project in Beijing. Routine monitoring is crucial for the reliability and stability of urban water supply. Compared with traditional monitoring methods, interferometric synthetic aperture radar (InSAR) has the advantages of large scale and high accuracy. Based on the small baseline subset InSAR, 187 ascending and 102 descending SAR images obtained from Sentinel-1 were used to detect the deformation along the diversion canal from 2017 to 2023. The results show that there was a sinking trend along the diversion canal. The subsidence was serious in the first half of the canal, and continued to sink from 2019 to 2020. The subsidence was alleviated in 2023. Combined with leveling measurements, the InSAR deformation monitoring results of important pumping station buildings were verified. The measurement accuracy of InSAR can reach the millimeter level. We extracted the groundwater level time series and subsidence for risky canal segments. Through pixel-by-pixel comparison, it was found that fluctuations in groundwater level would have some impact on surface deformation. Severe local subsidence or uplift deformation occasionally occurred. To ensure the safety of water diversion, the monitoring and maintenance of relevant pump station buildings in risky areas should be increased in the future.

Influence of ecological water diversion on the spatiotemporal distribution of groundwater in the Minqin Basin

This study examines the dynamic changes in groundwater levels and their spatial distribution in the Minqin Basin after the diversion of water from the ecosystem. It selected monitoring wells in different regions of the basin and analyzed the annual and seasonal fluctuations in groundwater levels before and after the water diversion. According to the findings, there is a notable shift in the rate of change in groundwater levels of the irrigated areas of the Minqin Basin: from an average of 0.62 m per year between 2001 and 2007 to a mere 0.01 m per year between 2008 and 2022. Since 2010, the groundwater level in the Qingtu Lake has increased by 1.01 m. The decline of Minqin Basin’s groundwater levels slowed down, and some places even witnessed rises in the groundwater level. The water levels in the region are generally stable.