Long-term Measurements Research Articles

Use of Long-Term Soil Respiration Measurements for Calculating the Net Carbon Balance in Ecosystems of the Central Chernozemic Region

Use of Long-Term Soil Respiration Measurements for Calculating the Net Carbon Balance in Ecosystems of the Central Chernozemic Region

Influence of atmospheric state on variability of long-term residual ambient sound level measurements in a subalpine valley.

Two natural influences on the acoustic environments of mountainous parks and communities are flowing water and shifting weather. A central purpose of the acoustic measurement design used by the United States National Park Service is to provide spectral estimates of residual ambient sound level metrics at a seasonal time scale. Acoustic monitoring sampling methodologies are often designed using a sequence of similar measurements. When source and residual ambient spectra overlap, an estimate of variability in the latter is beneficial to successful monitoring design. The observed and modelled effects of atmospheric state on sound level are analyzed to reveal variability due to these effects at a long-term monitoring site in Denali National Park, Alaska. The analysis of variability incorporates a covariate that is otherwise challenging to estimate in remote settings: vertical temperature gradients in the atmospheric boundary layer. Results reveal inversions (positive gradients) in the atmosphere ≥30% between 19:00 and 09:00. Inversion strengths above 0.06 °C/m are associated with 10-15 dB increases in sound level over hourly time scales. Because inversions tend to occur during otherwise quiescent times of day, they ultimately reduce seasonal variability at the site and corresponding uncertainty in noise metrics for transportation noise arriving from varied directions.

Continuous Health Monitoring of Reinforced Concrete Bridge Deck based on Traffic Load-induced Acoustic Emission

This paper presents continuous bridge deck monitoring based on b-value obtained from traffic load-induced acoustic emission (AE) signals. Using the self powered AE system that we developed, we have observed traffic load-induced AE on an actual bridge for five years. The developed self-powered AE system demonstrated that long-term traffic load-induced AE measurements over five years could be performed without an external power source. Traffic load-induced AEs measured irregularly by event-driven measurement were accumulated, and b-values were calculated. We used an additive regression model that accounts for piecewise linear trends and seasonality to extract long-term trends accurately. Over the past five years, the bridge has deteriorated. In addition, repairs were made during the period. As a result of this monitoring, we determined the relationship between the damage condition of the bridge and the b-value trend obtained from the traffic load-induced AEs. The results confirmed that the b-value based on traffic load-induced AE corresponds well with the damage conditions on the underside of the deck slab or in a shallow area inside it.

Drifted Uncertainty Evaluation of a Compact Machine Tool Spindle Error Measurement System

The accurate measurement of spindle errors, especially quasi-static errors, is one of the key issues for the analysis and compensation of machine tool thermal errors in machining accuracy. To quantitatively analyze the influence of the measurement system’s own drift on the measurement results, a drifted uncertainty evaluation method of the precision instrument considering the time drift coefficient is proposed. This study also produced a high-precision compact spindle error measurement device (with a displacement measurement error of less than ±1.33 μm and an angular measurement error of less than ±1.42 arcsecs) as the research object to verify the proposed drift uncertainty evaluation method. A method for evaluating the drift uncertainty of the measurement system is proposed to quantitatively evaluate the system error and drift uncertainty of the measurement device. Experiments show that the drift uncertainty evaluation method proposed in this paper is more suitable for evaluating the uncertainty changes in measurement instruments during long-term measurements compared to traditional methods.

Energy poverty and the green energy transition's impact upon income inequality in Latin America

In this study, we examine the relationships arising from the transition process to green economies and energy poverty in relation to income inequality across 22 Latin American countries during the period from 2000 to 2021. Our estimations are conducted using various estimators for energy poverty and the transition to green economies, employing feasible generalized least squares (FGLS) and panel corrected standard errors (PCSE) to ensure robustness. The results reveal a significant effect of both sets of variables on income inequality. Specifically, energy poverty contributes to higher levels of income inequality, while the ecological transition has the potential to address income inequality issues, provided an effective distribution of renewable energy resources among society is ensured. Failure to achieve equitable distribution of renewable energy resources may hinder the attainment of more egalitarian societies. To address this, a comprehensive set of policies is required to ensure equal access to renewable energy sources for the entire population, along with effective long-term measures that contribute to the equitable distribution of energy resources.

Climate change reduces the tension of conflicting selection pressures on breeding date in a passerine bird.

Unpredictably fluctuating environments create complex selective landscapes that shape the distribution of key life history traits. Identifying the mechanisms behind dynamic patterns of selection is difficult, yet essential for predicting responses to climate change. We combine long-term measures with field manipulation of natural selection on breeding date in a wild bird to investigate whether highly variable spring cold snaps drive fluctuating selection. We show that variation in cold snap intensity leads to fluctuating selection on breeding date-in weak cold snap years, selection was consistently negative; however, in strong cold snap years, its direction reversed. These patterns were mirrored in a field experiment; nests that were food supplemented during cold snaps avoided cold snap mortality leading earlier breeders to have higher fitness. In contrast, in the non-supplemented group earlier breeders had higher cold snap nest mortality and selection was positive. Using nearly a century of climate data, we show that cold snaps are becoming less frequent and paradoxically occurring later which should allow earlier breeders to avoid them, potentially releasing conflicting selection pressures and facilitating a rapid phenological shift. Thus, rather than constraining a species' ability to adapt, climate change can enable a rapid shift to a new phenotypic optimum.

Design and Implementation of an Automated Instrument for Battery Charging Experiments

Accurate and long-term measurements are essential in battery charging research and development, to evaluate and compare different techniques and their effectiveness. In such approaches, a very good control of certain charging parameters is also necessary, during several hours or even days. Thus, it became necessary to obtain an automatic instrument that could ensure the precision and repeatability of the experiments, but also the flexibility regarding the type and size of the b attery. This article presents the design, implementation and preliminary experimentation of an instrument for automation and monitoring of battery charge-discharge cycles. The tool adds exponential current pulses to the battery charging process, especially in the constant current phase. Such pulses are rarely addressed in the literature, although some studies suggest that they have the potential to improve batteries performance.

Provision of prostate cancer services in Tanzania: perspectives from five tertiary hospitals

BackgroundAccess to quality prostate cancer services remains a global challenge, particularly in Low- and Middle-Income countries. This is often due to weak health systems that struggle to meet the population’s needs. The provision of quality health services to patients with prostate cancer requires a comprehensive approach involving multiple stakeholders and structural inputs. However, few studies have comprehensively assessed the relationship between these structural inputs and prostate cancer treatment outcomes. This study, therefore, aimed to determine the availability of selected structural inputs and descriptions of how they influence the provision of quality services to patients with prostate cancer in Tanzania.MethodsWe conducted a cross-sectional study using an explanatory sequential mixed-method approach to collect data from five tertiary hospitals providing cancer services in Tanzania. A validated checklist was used to collect information on available structural inputs for prostate services at tertiary hospitals. A semi-structured interview guide was used to conduct 42 in-depth interviews with 20 healthcare providers, five hospital managers, and 17 patients undergoing treatment for prostate cancer. Descriptive analysis was performed for the quantitative data, and thematic analysis was conducted with the aid of NVivo 14 qualitative software for the interview transcripts.ResultsAll five assessed tertiary hospitals had inadequate human resources for health to provide prostate cancer services. Only one had 70% of the required HRH, while none had above 40% of the required HRH. Within the hospitals, the skill mix imbalance was severe across cadres. Five themes emerged: inadequate infrastructure, delays in diagnosis, delays in treatment, shortage of human resources for health (HRH), and inefficient organization of prostate cancer services.ConclusionThe findings of this study, underscore the major health system deficiencies for the provision of prostate cancer services in tertiary hospitals. With the increased aging population, strong health systems are vital in addressing conditions of old aging, including prostate cancers. Studies on optimization of the available HRH and infrastructure are needed to improve the provision of prostate cancer in tertiary hospitals as an interim solution while long-term measures are needed for improving the HRH availability and conducive infrastructure.

Long-term outcomes of avascular necrosis in sickle cell disease using joint-specific patient-reported outcome measures: Results from a multicentre study.

Avascular necrosis (AVN) is a prevalent and progressive complication in young patients with sickle cell disease (SCD), but no study evaluated the long-term subjective and objective outcome measures. Oxford hip score (OHS) and Oxford shoulder scores (OSS) are validated joint-specific patient-reported outcome measures (PROMs). In this prospective multicentre study, 47 SCD patients with pre-existing diagnosis of AVN occurred at a median age of 35.9 (24.2-47.6) filled out the OHS and OSS at median follow-up of 9.4 years (4.5-12.9). No patient died after diagnosis of AVN. Hip AVN was present in 34 (72%) patients, with bilateral involvement in 25 (74%); 26 (59%) underwent total hip arthroplasty (THA) at a median age of 34.6 (22.6-49.5); and 4 (15%) required re-surgery. OHS revealed moderate to severe impairment both in patients underwent THA and no hip surgery. Shoulder AVN was present in 13 (6%) patients and OSS revealed mild to moderate impairment. A high rate of compromised joint function and pain was observed 10 years after diagnosis of AVN regardless of the type of treatment, outlying the need to improve the management of this sickle-related complication. OHS and OSS are validated joint-specific PROMs easy to use in all SCD centres.

Analysis of the Impact of Digital Communication Tools on Organizational Culture and Communication Effectiveness Within Enterprises

The issue of improving the organizational culture of enterprises is becoming increasingly relevant in light of the need to enhance the effectiveness of human resources policy and employees’ motivation. Being aware of the importance of developing organizational culture and the effectiveness of internal communication, managers of enterprises very rarely have an information basis for a model of their effective construction. The study aims to analyze the current role of digital transformation tools within the communication process to optimize organizational culture and increase communication effectiveness. The research was conducted using the general methods of scientific cognition, in particular, analysis and synthesis, induction and deduction, abstraction, specification, and formalization. The study identified the potential of digital communication tools for the cultural and communication optimization of companies. The authors have analyzed the factors of insufficiently effective development of organizational culture. The article substantiates the need for the synergy of process, system-behavioral, adaptive-situational, psychodynamic, and competence approaches. The authors have proposed ways of digital transformation of organizational and communication culture. Based on this, the main vectors for optimizing the concept of organizational management of the transformation of the communication sphere of companies have been identified. It has been proved that the conceptual model of an effective organizational culture is based on long-term measures to implement the strategic goals of enterprise development through continuous self-development and continuous improvement of communication skills using modern and innovative digital tools.

Experiences of autistic people in supported employment in France: a participatory research project

Purpose The employment rate of autistic people is low, and they are often employed in low-paying jobs or in jobs involving tasks that fall short of their skills and competence. To address this situation, the individual placement and support method (IPS) offers promising perspectives for personalized and long-term support measures. This evidence-based method has produced positive results in several countries. IPS has been used in France only since 2016. This paper aims to examine the experience of autistic people in France who have benefitted from supported employment measures. Design/methodology/approach Nineteen autistic adults in France took part in semistructured interviews. Interview questions focused on work and measures to support employment. The authors analysed the interviews using reflexive thematic analysis, within the paradigm of critical realism. The authors adopted a participatory approach; the project was led by an autistic researcher and autistic individuals were included at all stages. Findings This study identified six primary themes and three subthemes across the data: (1) The uphill battle to obtain adjustments in the workplace; (2) insufficient knowledge of autism; (2.1) explaining again and again: the educative burden; (3) the challenge of making oneself heard; (3.1) when the entourage steps in; (4) support measures as material assistance and reassurance; (4.1) between benevolence and condescension; (5) organizational factors that affect the quality of support; and (6) personal and professional life are closely intertwined. Originality/value This research provides a better understanding of how autistic people experience supported employment in France and highlights ways to improve it. Job coaches play a crucial role in offering practical help and reassurance, and their efforts to nurture an active personal life are perceived positively. However, supported employment also carries the risk of limiting autistic individuals' capacity for action and causing several difficulties if job coaches are not well-informed about autism, do not reflect on their own attitudes, do not assist in obtaining necessary accommodations and if there are organizational problems leading to a lack of resources.

Measurement report: Contribution of atmospheric new particle formation to ultrafine particle concentration, cloud condensation nuclei, and radiative forcing – results from 5-year observations in central Europe

Abstract. As an important source of sub-micrometer particles, atmospheric new particle formation (NPF) has been observed in various environments. However, most studies provide little more than snapshots of the NPF process due to their underlying observations being limited in space and time. To obtain statistically relevant evidence on NPF across various environments, we investigated the characteristics of NPF based on a 5-year dataset of the German Ultrafine Aerosol Network (GUAN). The results were also compared with observations in previous studies, with the aim to depict a relatively complete picture of NPF in central Europe. The highest NPF occurrence frequency was observed in regional background sites, with an average of about 19 %, followed by urban background (15 %), low-mountain-range (7 %), and high Alpine (3 %) sites. The annual mean growth rate between 10 and 25 nm varied from 3.7–4.7 nm h−1, while the formation rate with same size range 10–25 nm from 0.4 to 2.9 cm−3 s−1. The contribution of NPF to ultrafine particles (UFPs) was about 13 %, 21 %, and 7 % for the urban background, regional background, and low mountain range, respectively. The influence of NPF on cloud condensation nuclei (CCN) number concentration and the aerosol extinction coefficient for NPF days was the highest in mountainous areas. These findings underscore the importance of local environments when assessing the potential impact of NPF on regional climate in models, and they also emphasize the usefulness of a long-term aerosol measurement network for understanding the variation in NPF features and their influencing factors over a regional scale.

Insights into solid-contact ion-selective electrodes based on laser-induced graphene: Key performance parameters for long-term and continuous measurements.

This work aims to serve as a comprehensive guide to properly characterize solid-contact ion-selective electrodes (SC-ISEs) for long-term use as they advance toward calibration-free sensors. The lack of well-defined SC-ISE performance criteria limits the ability to compare results and track progress in the field. Laser-induced graphene (LIG) is a rapid and scalable method that, by adjusting the CO2 laser parameters, can create LIG substrates with tunable surface properties, including wettability, surface chemistry, and morphology. Herein, we fabricate laser-induced graphene (LIG) solid-contact electrodes using different laser settings and subsequently convert them into ion-selective sensors using a potassium-selective membrane. We measure the aforementioned tunable surface properties and correlate them with resultant low-frequency capacitance and water layer formation in an effort to pinpoint their effects on the sensitivity (Nernstian response), reproducibility (E°' variation), and potential stability of the LIG-based SC-ISEs. More specifically, we demonstrate that the surface wettability of the LIG substrate, which can be tuned by controlling the lasing parameters, can be modified to exhibit hydrophobic (contact angle > 90°) and even highly hydrophobic surfaces (contact angle ≈ 130°) to help reduce sensor drift. Recommendations are also provided to ensure proper and robust characterization of SC-ISEs for long-term and continuous measurements. Ultimately, we believe that a comprehensive understanding of the correlation between LIG tunable surface properties and SC-ISE performance can be used to improve the electrochemical behavior and stability of SC-ISEs designed with a wide range of materials beyond LIG.

Fiducial Reference Measurement for Greenhouse Gases (FRM4GHG)

The Total Carbon Column Observing Network (TCCON) and the Infrared Working Group of the Network for the Detection of Atmospheric Composition Change (NDACC-IRWG) are two ground-based networks that provide the retrieved concentrations of up to 30 atmospheric trace gases, using solar absorption spectrometry. Both networks provide reference measurements for the validation of satellites and models. TCCON concentrates on long-lived greenhouse gases (GHGs) for carbon cycle studies and validation. The number of sites is limited, and the geographical coverage is uneven, covering mainly Europe and the USA. A better distribution of stations is desired to improve the representativeness of the data for various atmospheric conditions and surface conditions and to cover a large latitudinal distribution. The two successive Fiducial Reference Measurements for Greenhouse Gases European Space Agency projects (FRM4GHG and FRM4GHG2) aim at the assessment of several low-cost portable instruments for precise measurements of GHGs to complement the existing ground-based sites. Several types of low spectral resolution Fourier transform infrared (FTIR) spectrometers manufactured by Bruker, namely an EM27/SUN, a Vertex70, a fiber-coupled IRCube, and a Laser Heterodyne spectro-Radiometer (LHR) developed by UK Rutherford Appleton Laboratory are the participating instruments to achieve the Fiducial Reference Measurements (FRMs) status. Intensive side-by-side measurements were performed using all four instruments next to the Bruker IFS 125HR high spectral resolution FTIR, performing measurements in the NIR (TCCON configuration) and MIR (NDACC configuration) spectral range. The remote sensing measurements were complemented by AirCore launches, which provided in situ vertical profiles of target gases traceable to the World Meteorological Organization (WMO) reference scale. The results of the intercomparisons are shown and discussed. Except for the EM27/SUN, all other instruments, including the reference TCCON spectrometer, needed modifications during the campaign period. The EM27/SUN and the Vertex70 provided stable and precise measurements of the target gases during the campaign with quantified small biases. As part of the FRM4GHG project, one EM27/SUN is now used as a travel standard for the verification of column-integrated GHG measurements. The extension of the Vertex70 to the MIR provides the opportunity to retrieve additional concentrations of N2O, CH4, HCHO, and OCS. These MIR data products are comparable to the retrieval results from the high-resolution IFS 125HR spectrometer as operated by the NDACC. Our studies show the potential for such types of spectrometers to be used as a travel standard for the MIR species. An enclosure system with a compact solar tracker and meteorological station has been developed to house the low spectral resolution portable FTIR systems for performing solar absorption measurements. This helps the spectrometers to be mobile and enables autonomous operation, which will help to complement the TCCON and NDACC networks by extending the observational capabilities at new sites for the observation of GHGs and additional air quality gases. The development of the retrieval software allows comparable processing of the Vertex70 type of spectra as the EM27/SUN ones, therefore bringing them under the umbrella of the COllaborative Carbon Column Observing Network (COCCON). A self-assessment following the CEOS-FRM Maturity Matrix shows that the COCCON is able to provide GHG data products of FRM quality and can be used for either short-term campaigns or long-term measurements to complement the high-resolution FTIR networks.

Design and application of a prefabricated structure for large-span arch open-cut highway tunnels

To enhance construction efficiency, improve lining quality, and reduce project costs, this study proposes a prefabricated arch structure scheme for large-span open-cut highway tunnels, specifically targeting the ongoing construction of an eight-lane open-cut tunnel on Chongqing’s Xinsen Avenue. By establishing a finite element “load-structure” integrated calculation model and adopting an iterative analysis method, the impact of joint stiffness variations on internal force distribution was determined. Combined with long-term field monitoring and measurements, a thorough analysis was conducted on the performance of the prefabricated arch structure during different construction stages. The results indicate that after assembly into a ring, the structure undergoes a self-adaptive adjustment phase, during which the joints experience significant stress and deformation. Following top-layer backfilling and water level restoration, the axial force on the joints increases, while stress and deformation decrease, exerting a positive effect on the joint bearing capacity. From the construction period to post-opening operations, the stress variation experienced by the joints remains within a controllable range, demonstrating substantial safety margins. This fully validates the safety and reliability of the prefabricated arch structure scheme.

262 Why are some cows skinny? An evaluation of stress and immune factors

Abstract For the mature cow with low body condition scores (BCS), being too thin can accompany health issues, reduced pregnancy rates, more days to rebreeding, and decreased milk production resulting in lighter calves at weaning. In addition, reduced fat insulation in low BCS cows during the winter equates to additional feed requirements for warmth. The hypothesis of this study was that stress and immune factors contribute to low BCS in mature cows. The objective of this study was to determine whether there were differences in hematology parameters, hair cortisol concentrations, and plasma cytokine concentrations among animals with low body condition (BCS ≤ 4). Over a 3 yr study, we collected 62 pairs of cows which included cows with a BCS ≤ 4, and a matched control animal born in the same year with the same or similar breed composition from the same population of animals with a BCS of 5 or higher. Hematology parameters, cytokine concentration, and cortisol concentrations were analyzed using a model with BCS classification and sample year as fixed effects and age in years as a covariate. Hemoglobin, hematocrit, red blood cell and mean platelet volume were all less among the low BCS cows, and neutrophil count was greater (P < 0.05). Platelet, monocyte counts, mean corpuscular volume, and mean corpuscular hemoglobin tended to be greater in low BCS cows (0.05 < P ≤ 0.1), and lymphocyte count tended to be less. Hair cortisol concentrations, a longer-term measure of cortisol, tended to be greater in low BCS cows (P = 0.09). None of the 15 cytokines tested differed with BCS. The combination of reduced RBC parameters with greater neutrophils suggests that low BCS cows were responding to or were the reflection of some type of chronic stressor, such as a subclinical disease state or a physiologic stressor. This was also supported by the tendency for greater cortisol concentrations in low BCS cows. USDA is an equal opportunity provider and employer.

Aggregation-Induced Emission of Curcuminoid-BF2 Complex for Phosphor-Converted Red Light-Emitting Diode.

The incorporation of difluoroboron β-diketonate and tetraphenylethene under a facile Knoevenagel condensation reaction afforded one new D-π-A-π-D complex TCBF with high aggregation-induced emission (AIE) activity. The TCBF film can maintain a high photocurrent after long-term (500 min) photoelectronic measurements. The successful fabrication of a red LED device makes it a promising candidate for high-performance solid-state lighting.

Multiple indicators of gut dysbiosis predict all-cause and cause-specific mortality in solid organ transplant recipients

ObjectiveGut microbiome composition is associated with multiple diseases, but relatively little is known about its relationship with long-term outcome measures. While gut dysbiosis has been linked to mortality risk in...

A Study on Miniaturized In-Situ Self-Calibrated Thermometers Based on Ga and Ga-Zn Fixed Points.

In order to ensure the reliability and accuracy of long-term temperature measurement where the thermometers are discommodious or even impossible to access for conventional periodical calibration, a study on miniaturized in-situ self-calibrated (MISSC) thermometers based on Ga and Ga-Zn fixed points was conducted using temperature scale transfer technology. One MISSC thermometer consists of three parts: the first is the fixed-points hardware, including a container with two cells separately filled with Ga and Ga-Zn; the second is the temperature sensing hardware, made of a Type T thermocouple; the third is the mini-power heating hardware, made of a film resistance. The measurement and calibration (M&C) system comprises a temperature measurement and data processing subsystem and a mini-power heating control subsystem. Then, an in-situ self-calibration can be carried out by mini-power heating from a room temperature of about 20 °C, and then by comparison between the measured phase transition plateau results and the standard fixed-points, i.e., Ga fixed point (about 29.76 °C) and Ga-Zn fixed point (about 25.20 °C). A series of experiments were performed, and the results show that: (1) both the proposed hardware design and the self-calibration method are feasible, and (2) the Φ16 mm × 25 mm MISSC thermometer is found to be the most miniaturized one that can realize reliable self-calibration in this study.

Reconciling short- and long-term measurements of coastal cliff erosion rates

Oblique terrestrial laser scanning (TLS) enables topographic change detection at scales (10−1 –100 cm) that are appropriate for coastal cliff erosion monitoring. Despite this, published applications of TLS on cliff are limited to a small number of sites around the world. Here we report new TLS point cloud datasets from 9 years of monitoring (2014–2023) at Rothesay Bay within the Hauraki Gulf, New Zealand, which has relatively low wave energy and a meso-tidal range. The 120 m-length scan area includes cliffs of 10–30 m height, formed of horizontally bedded soft sedimentary flysch rock. The cliffs are fronted by an 140 m wide near-horizontal shore platform that terminates in an abrupt seaward edge. Previous research at this site has estimated long-term cliff erosion rates within a range of 1.4 ± 0.1 to 14.3 ± 0.1 mm/year on the basis of measured shore platform width, assuming that the shore platform has widened over time over 6000 years of stable Holocene sea level, and that the seaward edge of the shore platform has not retreated. Volumetric cliff-face erosion rates were detected through 17 scans over a 9-year window (2014–2023), including intensive monthly TLS scanning between July 2021 and July 2022. Results show that the average cliff recession rate over the past decade has been 41 ± 2 mm/year, and monthly scans show a range in erosion rates of 30 to 288 mm/year. The cliff recession rate detected with TLS is 3 to 30 times higher than erosion rates derived based on the shore platform width. If erosion had been constant at this rate over approximately 6000 years, a total cliff retreat of >245 m would be expected, whereas the contemporary shore platform is only 140 m wide. We discuss two possible hypotheses for the confounding width of the modern shore platform: 1) that modern cliff retreat rates are faster than past erosion rates; 2) that the seaward edge of the shore platform does not reliably demarcate Holocene cliff recession. We present new bathymetric survey mapping seaward of the shore platform edge that reveals multiple rocky features that are distinguished by steep slope breaks and planar surfaces. Understanding the evolution of the intertidal shore platforms during the Holocene era may necessitate new insights on how cliffs formed toward the end of the last marine transgression. This could potentially be investigated through the study of subtidal marine bathymetry.