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Our purpose was to determine how age affects metabolic flexibility and underlying glucose kinetics in healthy young and older adults. Therefore, glucose and lactate tracers along with pulmonary gas exchange data were used to determine glucose kinetics and respiratory exchange ratios [RER = carbon dioxide production (V̇co2)/oxygen consumption (V̇o2)] during a 2-h 75-g oral glucose tolerance test (OGTT). After an 12-h overnight fast, 28 participants, 15 young (21-35 yr; 7 men and 8 women) and 13 older (60-80 yr; 7 men and 6 women), received venous primed-continuous infusions of [6,6-2H]glucose and [3-13C]lactate with a [Formula: see text] bolus. After a 90-min metabolic stabilization and tracer equilibration period, volunteers underwent an OGTT. Arterialized glucose concentrations ([glucose]) started to rise 15 min post glucose consumption, peaked at 60 min, and remained elevated. As assessed by rates of appearance (Ra) and disposal (Rd) and metabolic clearance rate (MCR), glucose kinetics were suppressed in older compared to young individuals. As well, unlike in young individuals, fractional gluconeogenesis (fGNG) remained elevated in the older population after the oral glucose challenge. Finally, there were no differences in 12-h fasting baseline or peak RER values following an oral glucose challenge in older compared to young men and women, making RER an incomplete measure of metabolic flexibility in the volunteers we evaluated. Our study revealed that glucose kinetics are significantly altered in a healthy aged population after a glucose challenge. Furthermore, those physiological deficits are not detected from changes in RER during an OGTT.NEW & NOTEWORTHY To determine metabolic flexibility in response to an OGTT, we studied healthy young and older men and women to determine glucose kinetics and changes in RER. Compared to young subjects, glucose kinetics were suppressed in older healthy individuals during an OGTT. Surprisingly, the age-related changes in glucose flux were not reflected in RER measurements; thus, RER measurements do not give a complete view of metabolic flexibility in healthy individuals.

Few studies have examined the N kinetics of individual feeds with stable isotope tracing. We hypothesized that N partitioning to milk and excreta pools as well as the rates of the processes that drive this partitioning would differ for alfalfa silage, corn silage, corn grain, and soybean meal. Feed ingredients were endogenously labeled with 15N and included in 4 diets to create treatments with the same dietary composition and different labeled feed. Diets were fed to 12 late-lactation dairy cows for 4 d (96 h) and feces, urine, and milk collection proceeded during the 4 d of 15N enrichment and for 3 d (80 h) after cessation of label feeding. Nonlinear models of 15N enrichment and decay were fit to milk (MN), urine (UN), and fecal N (FN) in R with the nlme package, and feed-specific parameter estimates were compared. The estimated proportions of feed N that were excreted in feces supported our understanding that N from soybean meal and corn grain is more digestible than N from alfalfa and corn silage. Estimates for the N partitioning between milk and urine from the 2 concentrate feeds (soybean meal and corn grain) indicated that UN/MN ratios were less than or equal to 1:1, indicating either more or equal nitrogen partitioning to milk compared with urine. It is important to maintain factual accuracy in representing the results rather than implying a desired outcome unsupported by the data. In contrast, UN/MN ratios for forage feeds (corn and alfalfa silage) were >1:1, indicating more N partitioning to urine than milk. The modeled proportion of total FN that originated from feed N was 82.2%, which is in line with previous research using a similar 15N measurement timeframe. However, the proportion of urinary and MN originating from feed N was much lower (60.5% for urine, 57.9% for milk), suggesting that approximately 40% of urinary and MN directly originate from body N sources related to protein turnover. The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. [Display omitted] [ABSTRACT FROM AUTHOR]

Laser-induced fluorescence (LIF) is an established noninvasive measurement method to determine temperature distributions and local gas concentrations in combustion processes with high spatial and temporal resolution. This work presents high-precision LIF spectra of acetone and other tracers at ambient conditions. By using a large UV-sensitive sCMOS camera instead of an image intensified camera, many issues like nonlinearity, varying sensitivity, vignetting, limited resolution etc. could be minimized or eliminated. Particular care was taken to remove residual stray light and to calibrate the spectra with metrological traceability to the International System of Units SI. [ABSTRACT FROM AUTHOR]

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Abstract Tracer tests are an important tool for characterizing and monitoring subsurface reservoir properties. However, they are limited both because of the tracer molecules constraining factors such as irreversible adsorption, retention, and degradations, i.e. interaction processes of fluorophore molecule with surrounding media resulting in a large variation in transport properties. Elaborate tests utilizing more than one tracer to distinguish time or location of injection are complex and interpretation is ambiguous because each tracer interacts differently. In this study, we present an approach to increase tracer stability and enhance the transport uniformity of different tracers, thus making tests utilizing multiple tracers simpler and more feasible. We present this concept of tracer multiplicity by encapsulating an anionic, cationic or amphoteric fluorophore inside mesoporous silica nanoparticle carriers coated with a protective titania layer. Upon encapsulation, increased thermal resistance and drastically lowered sorption affinity towards quartz sand was detected in batch and flow-through experiments. An additional advantage of the presented nanoparticle tracers over molecular tracers is their modularity, which is demonstrated by surface modifications and application of additives that greatly reduce sorption and increase recovery rates in the flow experiments. With the here presented concept of tracer multiplicity, we introduce a new approach for colloidal tracer design that has the potential to expand and enhance measurable parameters, measurement accuracy and simplicity of analysis.

Our purpose was to determine how age affects metabolic flexibility and underlying glucose kinetics in healthy young and older adults. Therefore, glucose and lactate tracers along with pulmonary gas exchange data were used to determine glucose kinetics and respiratory exchange ratios [RER = carbon dioxide production (V̇ co 2)/oxygen consumption (V̇ o 2)] during a 2-h 75-g oral glucose tolerance test (OGTT). After an 12-h overnight fast, 28 participants, 15 young (21–35 yr; 7 men and 8 women) and 13 older (60–80 yr; 7 men and 6 women), received venous primed-continuous infusions of [6,6-2H]glucose and [3-13C]lactate with a H 13 C O 3 − bolus. After a 90-min metabolic stabilization and tracer equilibration period, volunteers underwent an OGTT. Arterialized glucose concentrations ([glucose]) started to rise 15 min post glucose consumption, peaked at 60 min, and remained elevated. As assessed by rates of appearance (Ra) and disposal (Rd) and metabolic clearance rate (MCR), glucose kinetics were suppressed in older compared to young individuals. As well, unlike in young individuals, fractional gluconeogenesis (fGNG) remained elevated in the older population after the oral glucose challenge. Finally, there were no differences in 12-h fasting baseline or peak RER values following an oral glucose challenge in older compared to young men and women, making RER an incomplete measure of metabolic flexibility in the volunteers we evaluated. Our study revealed that glucose kinetics are significantly altered in a healthy aged population after a glucose challenge. Furthermore, those physiological deficits are not detected from changes in RER during an OGTT. NEW & NOTEWORTHY: To determine metabolic flexibility in response to an OGTT, we studied healthy young and older men and women to determine glucose kinetics and changes in RER. Compared to young subjects, glucose kinetics were suppressed in older healthy individuals during an OGTT. Surprisingly, the age-related changes in glucose flux were not reflected in RER measurements; thus, RER measurements do not give a complete view of metabolic flexibility in healthy individuals. [ABSTRACT FROM AUTHOR]

Sentinel lymph node (SLN) detection with superparamagnetic iron oxide (SPIO) nanoparticles has been widely studied and standardized for breast and prostate cancer, but there is scarce evidence concerning its use in vulvar cancer. The objective of this study was to compare SLN detection using a SPIO tracer injected at the time of the surgery detected by a magnetometer, with the standard procedure of using a technetium 99 radioisotope (Tc99) detected by a gamma probe, in patients with vulvar cancer. The SPIO vulvar cancer study was a single-center prospective interventional non-inferiority study of SPIO compared to Tc99, conducted between 2016 and 2021 in patients who met the GROINSS-V study inclusion criteria for selective sentinel lymph node dissection in vulvar cancer. We included 18 patients and a total of 41 SLNs. The level of agreement between tracers was 92.7% (80.6%–97.4%), corresponding to 38 out of 41 SLNs, which confirms the non-inferiority of SPIO compared to Tc99. The SLN detection rate per groin was 96.3 (81.7%-99.3) using Tc99 and 100% (87.5%–100%) using SPIO. Both tracers had a detection rate of 100% for positive lymph nodes. The use of SPIO as a tracer for detecting SLNs in patients with vulvar cancer has shown to be non-inferior to that of the standard radiotracer, with the advantages of not requiring nuclear medicine and being able to inject it at the time of surgery after induction of anesthesia. • This study proposes SPIO as a reasoned alternative to Tc99 for detecting SLNs in vulvar cancer. • The use of SPIO has shown to be non-inferior to detecting SLNs in patients with vulvar cancer versus Tc99. • SPIO can be injected prior to surgery, after induction of anesthesia and without the need for the nuclear medicine service. [ABSTRACT FROM AUTHOR]

The loss of soluble cationic species by adsorption to glass vial walls is problematic for experiments performed at tracer concentrations. Silanization increases glass hydrophobicity to reduce cation sorption to glass surfaces. This work examines the efficacy of silanization in decreasing europium and thorium loss through glass sorption in aqueous and mixed aqueous/organic phases. The influence of the solution pH, ionic strength, electrolyte, metal concentration, organic diluent's nature, and the addition of complexing extractants was investigated. Overall, results indicate that silanization effectively decreases cation loss to sorption to glass walls. [ABSTRACT FROM AUTHOR]

Objectives: Regional lymph node (LN) volume decreases after neoadjuvant therapy, requiring a tracer for more accurate detection. Nano‐carbon tracer is a third‐generation tracer with several advantages, but its use for LN detection after neoadjuvant chemoradiotherapy for middle and low rectal cancer remains unclear. Therefore, this study investigated the effects and safety of anoscope‐guided subrectal injections of nano‐carbon suspension in this patient population. Methods: This study retrospectively reviewed the medical records of 45 patients with middle and low rectal cancer admitted to our institution from March 2019 to March 2022. All patients received preoperative neoadjuvant chemotherapy and radiotherapy and were divided into nano‐carbon injection (n = 23; anoscope‐guided injections of nano‐carbon suspension in the rectal submucosa 2 cm above the dentate line 24 h preoperatively) and control (n = 22; directly underwent surgery) groups. The LN detection and complication rates were compared between the groups. Results: The total and mean numbers of LNs and small LNs and the number of patients with > 12 LNs were significantly higher in the nano‐carbon injection group than in the control group. The total number of positive LNs and LN metastasis did not differ between the groups, nor did the anastomotic leakage, bleeding, stenosis, and abscess occurrence rates. Conclusions: Anoscope‐guided nano‐carbon lymphatic tracing increased the LN detection rate, caused less trauma, and resulted in fewer postoperative complications than the direct surgical procedure. Thus, it is an effective, safe, and practical method that may improve dissections and the postoperative pathological staging accuracy. [ABSTRACT FROM AUTHOR]

Riverbed sediments have been identified as temporary and long-term accumulation sites for microplastic particles (MPs), but the relocation and retention mechanisms in riverbeds still need to be better understood. In this study, we investigated the depth-specific occurrence and distribution (abundance, type, and size) of MPs in river sediments down to a depth of 100 cm, which had not been previously investigated in riverbeds. In four sediment freeze cores taken for the Main River (Germany), MPs (≥ 100 µm) were detected using two complementary analytical approaches (spectroscopy and thermoanalytical) over the entire depth with an average of 21.7 ± 21.4 MP/kg or 31.5 ± 28.0 mg/kg. Three vertical trends for MP abundance could be derived, fairly constant in top layers (0–‍30 cm), a decrease in middle layers (30–60 cm), and a strong increase in deep layers (60–100 cm). The dominant polymer types were polyethylene (PE), polypropylene (PP), and polystyrene (PS). Polyethylene terephthalate (PET) and PP were also found in deep layers, albeit with the youngest age of earliest possible occurrence (EPO age of 1973 and 1954). The fraction of smaller-sized MPs (100–500 µm) increased with depth in shallow layers, but the largest MPs (> 1 mm) were detected in deep layers. Based on these findings, we elucidate the relationship between the depth-specific MP distribution and the prevailing processes of MP retention and sediment dynamics in the riverbed. We propose some implications and offer an initial conceptual approach, suggesting the use of microplastics as a potential environmental process tracer for driving riverbed sediment dynamics. [ABSTRACT FROM AUTHOR]

Effectively managing water resources in karst systems requires a thorough understanding of their general conduit network along with their seasonal dynamics. Their investigation has involved well construction or several advanced natural tracer data, most of which are not always available. Hence, this work showcases a pragmatic approach that makes use of basic hydrochemical variables of springs with coarse temporal resolution in characterising a karst system. In this study's example, physicochemical variables like major ion concentrations/ratios, Electrical Conductivity (EC), pH and water temperature (Tw) were measured on 20-day basis for a hydrological year at the Louros Catchment, Greece. We further performed the frequency distribution and variation analysis of EC and Tw, principal component analysis (PCA), scatter plots of carbonate ions vs sulphate and hydrochemographs to determine relevant hydrochemical processes and hydrogeological features. PCA and the scatter plots showed that the simple-type upper karst level is entirely dominated by carbonate dissolution, whereas the complex-type middle and lower levels also involve gypsum and dolomite dissolution. Presence of mixing between karst units was also detected. EC and Tw analyses revealed the degree of karstification of different units and relative depths of flow systems. Hydrochemographs reflected the seasonality of limestone and gypsum dissolution's contributions linked to the dominant flow type (conduit vs diffuse). This study thus was able to demonstrate the usefulness of such holistic hydrochemical analyses to better understand karst systems. Given their cost-effectiveness, they can be easily applied to any understudied karst system worldwide. [ABSTRACT FROM AUTHOR]

This study represents the first use of the artificial radionuclides 129I and 236U, released into the ocean mainly from Nuclear Reprocessing Plants, as a dual tracer in the vicinity of Iceland with novel estimation of ocean circulatory pathways and mixing in the region. Iceland lies at the gateway to the Arctic where warm, saline Atlantic waters interact with waters of Arctic origin in ways that have critical consequences for the strength and stability of the Atlantic Meridional Overturning Circulation. Many of these interactions are not yet fully understood, such as how Atlantic water circulates around the Arctic Ocean and Nordic Seas and the composition and fate of the major overflows of the Greenland‐Scotland Ridge. Using new and previous measurements of 129I and 236U in seawater, we present a new method of appraising water mass provenance and mixing in the form of the 129I–236U dual mixing plot. With this method, we estimate that at least half the Atlantic‐origin water entering the Arctic Ocean circulates around the Canada Basin before exiting at Fram Strait and that this outflow is increased by about 40% by mixing with Return Atlantic Water "short‐circuiting" the Arctic Ocean at Fram Strait. We present tracer‐based evidence that water carried by the East Greenland Current has an unbroken pathway to the Faroe‐Shetland Channel and that Iceland‐Scotland Overflow Water (ISOW) entrains 60% Labrador Sea Water during transit past southeast Iceland. We present an unambiguous way to differentiate ISOW from DSOW after they partially merge in the Irminger Sea. Plain Language Summary: This study is the first to use a pair of man‐made nuclear products to study ocean currents near Iceland. Understanding these currents is important because Iceland sits where warm Atlantic waters meet colder Arctic waters, affecting a key ocean circulation system and the global climate. However, many details about how these waters move and mix are still unclear. Using new and previous measurements of these tracers in seawater, we demonstrate a new method to estimate the origins of currents and how they mix. We estimate that the outflow of Atlantic‐origin water from the Arctic Ocean at Fram Strait is increased by about 40% by Atlantic water bypassing the Arctic Ocean altogether at this location. Some of this Atlantic‐origin water then flows all the way from Iceland to Shetland in an unbroken pathway and the water that spills over the Iceland‐Scotland ridge increases by 60% by mixing with water from the Labrador Sea southeast of Iceland. Finally, we present a new way to distinguish this Iceland‐Scotland Overflow Water from similar water that overflows the ridge at Denmark Strait. Key Points: Recirculating Atlantic Water contributes about 40% to Atlantic layer of the East Greenland CurrentAtlantic‐origin waters can be traced from the East Greenland Current to the Faroe‐Shetland ChannelIceland‐Scotland Overflow Water and Denmark Strait Overflow Water are traceable separately after joining Deep Western Boundary Current [ABSTRACT FROM AUTHOR]

Anthropogenic perturbations from fossil fuel burning, nuclear bomb testing, and chlorofluorocarbon (CFC) use have created useful transient tracers of ocean circulation. The atmospheric 14C/C ratio (∆14C) peaked in the early 1960s and has decreased now to pre‐industrial levels, while atmospheric CFC‐11 and CFC‐12 concentrations peaked in the early 1990s and early 2000s, respectively, and have now decreased by 10%–20%. We present the first analysis of a decade of new observations (2007 to 2018–2019) and give a comprehensive overview of the changes in ocean ∆14C and CFC concentration since the WOCE surveys in the 1990s. Surface ocean ∆14C decreased at a nearly constant rate from the 1990–2010s (20‰/decade). In most of the surface ocean ∆14C is higher than in atmospheric CO2 while in the interior ocean, only a few places are found to have increases in ∆14C, indicating that globally, oceanic bomb 14C uptake has stopped and reversed. Decreases in surface ocean CFC‐11 started between the 1990 and 2000s, and CFC‐12 between the 2000–2010s. Strong coherence in model biases of decadal changes in all tracers in the Southern Ocean suggest ventilation of Antarctic Intermediate Water was enhanced from the 1990 to the 2000s, whereas ventilation of Subantarctic Mode Water was enhanced from the 2000 to the 2010s. The decrease in surface tracers globally between the 2000 and 2010s is consistently stronger in observations than in models, indicating a reduction in vertical transport and mixing due to stratification. Plain Language Summary: The ocean contains many dissolved gases that can be measured by sampling ocean water from ships. Some of these dissolved gases are changing over time because their atmospheric concentrations are changing. By measuring these changes in the ocean, we can learn about ocean transport and mixing, which is an important factor regulating climate change. We describe ocean measurements from the past three decades of radiocarbon in dissolved inorganic carbon, that was affected by nuclear bomb testing, and of chlorofluorocarbon gases, CFCs, that were banned in the 1990s due to their destructive effects on the ozone layer. The measurements show how their oceanic distributions have changed, as a result of their atmospheric histories and the patterns of ocean uptake and transport. By comparing the measurements with ocean models, we can identify biases in the models that affect how well future climate change can be predicted. In the most recent decade, the presence of all three tracers is shown to be decreasing in the upper ocean, a reversal of the preceding decades. Also in the most recent decade, the decrease in surface tracers is stronger in the observations than the models, suggesting a change to upper ocean mixing and stratification. Key Points: Recent trends in upper ocean Δ14C, pCFC‐11, and pCFC‐12 are negative, reflecting their decreasing atmospheric trendsIncreases in ∆14C are only observed in a few places over 2000–2010s, showing oceanic bomb 14C uptake has stopped and reversedModel‐data Δ14C and chlorofluorocarbon differences could be consistent with decadal ventilation changes and large‐scale stratification or model errors [ABSTRACT FROM AUTHOR]

Intervertebral Disc Degeneration is a pathophysiological condition that primarily affects the spinal discs, causing back pain and neurological deficits. It is caused by the contribution of several factors such as genetic predisposition, age-related degeneration, and lifestyle choices like obesity and physical activity. Even though there are medications to treat pain, there is a lack of medicines for a complete cure. The main difficulty lies in poor diagnosis of the morphological and functional changes in the disc. With the ever-increasing research on bioimaging techniques, new techniques are being developed and repurposed to evaluate disc shape and composition, and their defects like thinning or deformities on the disc, leading to the proper diagnostic intervention in intervertebral disc degeneration. In this review, we aim to present a comprehensive overview of the imaging techniques used in the pre-clinical and clinical stages for the diagnosis of intervertebral disc degeneration. First, we will discuss about patho-anatomy and the pathophysiology of degenerative disc disease with the significance and a brief description of various dyes and tracers utilized for bioimaging. Then we will shed light on the latest advancements in diagnostic modalities in intervertebral disc degeneration; concluded by an analysis of the repercussions of the methodologies and experimental systems employed in identifying mechanisms and developing therapeutic strategies in intervertebral disc degeneration.

Sand bodies in distributary channels and mouth bars of shallow water deltas are often distributed in continuous sheets， making it difficult to accurately classify the single sand body， limiting the accurate prediction of remaining oil distribution and restricting the further enhanced oil recovery （EOR）. Based on core， well logging， and other data， the characteristics of the sedimentary architectures of single sand bodies in shallow water deltas in the 1st Submember of the 2nd Member of the Eocene Shahejie Formation （Es21） and the 2nd Submember of 2nd Member of the Eocene Shahejie Formation （Es22） in Shenger District of Shengtuo Oilfield， Dongying Sag were systematically analyzed by using dense well pattern and interwell tracer data. The results show that shallow water delta deposits are developed in Es21 and Es22 in Shenger District of Shengtuo Oilfield， Dongying Sag， including plain subfacies and front subfacies of shallow water deltas. In addition， microfacies such as distributary channels， overbanks， mouth bars， and beach bars are developed. The sand bodies of shallow water deltas were divided into four architecture units （Levels 5-8）， and the single sand bodies in this study belong to the level-8 architecture unit. Six types of lateral contact patterns between single sand bodies were identified by comprehensively using dense well pattern and interwell tracer data： channel-overbank-channel splicing type， channel-channel cutting and stacking type， beach bar-beach bar splicing type， mouth bar-mouth bar splicing type， channel on dam cutting mouth bar type， and mudstone separating type. Interwell tracer data show that the sand body has the best connectivity in the channel on dam cutting mouth bar type， followed by channel-channel cutting and stacking type， mouth bar-mouth bar splicing type， and beach bar-beach bar splicing type. The worst connectivity is from the channel-overbank-channel splicing type. Finally， the sedimentary architecture models of single sand bodies in shallow water deltas in the study area were established. The microfacies type of the shallow water delta plain is mainly a distributary channel. The contact patterns between sand bodies in a single distributary channel mainly include lateral incising and overlapping， lateral contact with sand bodies on an overbank， vertical superposition， and oblique superposition. The microfacies types of sand bodies in the shallow water delta front are distributary channels， mouth bars， and beach bars. The contact patterns between sand bodies in a single mouth bar include vertical superposition， lateral splicing， oblique superposition， and mudstone separation. Two types of lateral splicing and vertical superposition exist between sand bodies in a single beach bar.

Abstract Background Both in clinical routine and in preclinical research, the established standard procedure for the final purification of radiometal-labeled peptide radiopharmaceuticals is cartridge-based reversed-phase (RP) solid phase extraction (SPE). It allows the rapid and quantitative separation of the radiolabeled peptide from hydrophilic impurities and easy integration into automated synthesis procedures. However, product elution from RP cartridges necessitates the use of organic solvents and product recovery is sometimes limited. Thus, an alternative purification method based on commercially available size exclusion cartridges was investigated. Results Since most peptide radiopharmaceuticals have a molecular weight > 1 kDa, Sephadex G10 cartridges with a molecular size cut-off of 700 Da were used for the final purification of a broad palette of 68Ga-, 64Cu- and 99mTc-labeled experimental peptide radiotracers as well as the clinically relevant ligand PSMA-617. Results (radiochemical purity (RCP, determined by ITLC), recovery from the solid support) were compared to the respective standard RP-SPE method. Generally, retention of unreacted 68Ga, 64Cu and 99mTc salts on the G10 cartridges was quantitative up to the specified elution volume (1.2 mL) for 68Ga and 99mTc and 99.6% for 64Cu. Even at increased elution volumes of 1.5-2 mL, RCPs of the eluted 68Ga- and 99mTc -radiopeptides were > 99%. For all peptides with a molecular weight ≥ 2 kDa, product recovery from the G10 cartridges was consistently > 85% upon respective adjustment of the elution volume. Product recovery was lowest for [68Ga]Ga-PSMA-617 (67%, 1.2 mL to 84%, 2 mL). The pH of the final product solution was found to be volume-dependent (1.2 mL: pH 6.3; 1.5 mL: pH 5.9; 2 mL: pH 5.5). Notably, the G10 cartridges were reused up to 20 times without compromising performance, and implementation of the method in an automated radiosynthesis procedure was successful. Conclusions Overall, size exclusion purification yielded all peptide radiopharmaceuticals in excellent radiochemical purities (> 99%) in saline within 10–12 min. Although product recovery is marginally inferior to classical SPE purifications, this method has the advantage of completely avoiding organic solvents and representing a cost-effective, easy-to-implement purification approach for automated radiotracer synthesis.

This study aimed to compare the water age in a drinking water distribution network (DWDN) using tracers and EPANET. The results indicate that all DWDN have residence times within the “short” time. established by the EPA and does not represent quality problems. These two techniques provided similar estimates of water age with small differences at points close to the treatment plant. This difference may be due to the fact that tracers can be retained in pipes, which overestimates the age of the water; meanwhile, EPANET could underestimate residence times due to the calibration or simplified representation of the network.

Silicon steel (electrical steel) has been used in electric motors that are important components in sustainable new energy Electrical Vehicles (EVs). The Ruhrstahl–Heraeus process is commonly used in the refining process of silicon steel. The refining effect inside the RH degasser is closely related to the flow and mixing of molten steel. In this study, a 260 t RH was used as the prototype, and the transport process of the passive scalar tracer (virtual tracer) and salt tracer (considering density effect) was studied using numerical simulation and water model research methods. The results indicate that the tracer transports from the up snorkel of the down snorkel to the bottom of the ladle, and then upwards from the bottom of the ladle to the top of the ladle. Density and gravity, respectively, play a promoting and hindering role in these two stages. In different areas of the ladle, density and gravity play a different degree of promotion and obstruction. Moreover, in different regions of the ladle, the different circulation strength leads to the different promotion degrees and obstruction degrees of the density. This results in the difference between the concentration growth rate of the salt tracer and the passive scalar in different regions of the ladle top. From the perspective of mixing time, density and gravity have no effect on the mixing time at the bottom of the ladle, and the difference between the passive scalar and NaCl solution tracer is within the range of 1–5%. For a larger dosage of tracer case, the difference range is reduced. However, at the top of the ladle, the average mixing time for the NaCl solution case is significantly longer than that of the passive scalar case, within the range of 3–14.7%. For a larger dosage of tracer case, the difference range is increased to 17.4–41.1%. It indicates that density and gravity delay the mixing of substances at the top area of the ladle, and this should be paid more attention when adding denser alloys in RH degasser. [ABSTRACT FROM AUTHOR]

Purpose: To explore the clinical application value of indocyanine green (ICG)–rituximab in sentinel lymph node biopsy. Methods: This study included 156 patients with primary breast cancer: 50 patients were enrolled in dose-climbing test, and 106 patients were enrolled in verification test. This was to compare the consistency of ICG–rituximab and combined method in the detected lymph nodes. Results: According to the verification test, the imaging rate of ICG–rituximab was 97.3%. Compared with the combined method, the concordance rate of fluorescence method was 0.991 (28 + 78/107; p < 0.001). Conclusion: For ICG–rituximab as a fluorescent targeting tracer, the optimal imaging dose of ICG 93.75 μg/rituximab 375 μg can significantly reduce the imaging of secondary lymph nodes. Compared with the combined method, it has a higher concordance rate. [ABSTRACT FROM AUTHOR]

Groundwater‐surface water interactions (GSI) connect rivers and streams with riparian areas and the adjacent aquifer. Although these interactions exert a substantial control of quantity and quality of both groundwater and surface water, knowledge on GSI along rivers at the regional scale, particularly for inland waterways, is still limited. We investigated GSI along the river Moselle, an important federal inland waterway in Germany, by using radon and tritium to identify gaining (water flux from the aquifer to the surface water) and losing (water flux from the surface water to the aquifer) stream conditions, respectively. Gaining stream conditions were identified by continuously measuring radon along the river during boat surveys with a high spatial resolution (every 2 km) during intermediate (October 2020) and near low flow conditions (August/September 2021). The tritium concentrations in surface water and groundwater and the resulting tritium inventories were used to characterize losing stream conditions Monthly tritium inventories from 2017 to 2022 revealed a mean loss for the whole period of 20.3 % and a mean gain of 21.8%. Both were probably triggered by a combination of losing stream conditions and flood‐induced mass transfer of water from the aquifer back into the river as well as discharge fluctuations. At the investigated site Lehmen there were direct indications of an influence of surface water due to elevated tritium concentrations in the groundwater (up to 13.3 Bq L−1). Using radon mass balance modelling, good agreements of simulated versus measured radon data with respect to two groundwater end‐member scenarios were obtained during intermediate flow (Spearman's ρ: 0.97 and 0.99; MAE: 10.1 and 3.4 Bq L−1) and near low flow (Spearman's ρ: 0.97 and 0.99; MAE: 11 and 6.5 Bq L−1). Considerable groundwater inflow was limited to the meander of Detzem, where cumulated groundwater inflow of about 19 m3 s−1 (9.5% of total discharge) and 4.2 m3 s−1 (3.8% of total discharge) was simulated during intermediate and near low flow, respectively. However, the groundwater inflow was relatively low compared to alpine streams, for example. The study will help to better identify and quantify GSI at the regional scale and provide methodological guidance for future studies focusing on inland waterways. [ABSTRACT FROM AUTHOR]

Volcanic regions have complicated groundwater flow systems because of their geological structures, and the effects of rainfall on their groundwater recharge/discharge are still largely unknown. A field survey and chemical analyses were conducted on springs near an andesitic volcano in Japan to investigate changes in groundwater flow processes associated with heavy rainfall. After heavy rainfall, some springs showed a decrease in tracer values while others at lava or pyroclastic flow termini were stable. This indicates that the rainfall component rapidly discharges or the bedrock groundwater component discharges from deeper subsurface areas depending on the structure, length, and permeability of the volcanic ejecta. Hence, the groundwater mixing process in areas with ejecta can be approximated by the binary mixing model. In contrast, tracer values increased after heavy rainfall in areas near agricultural land, which suggests that nitrate ions were loaded into groundwater. Thus, the changes in various groundwater flow processes in volcanic regions after rainfall can be attributed to not only geological/geographical differences but also the groundwater stored in mountain bodies. [ABSTRACT FROM AUTHOR]

Peatlands are hydrologically significant landscape units in mountain headwater catchments in Central Europe. In this study, the contribution of a peat bog to runoff and its annual water balance were analysed and compared with those of a forested mineral soil hillslope. A mixing model method using the water temperature as a tracer was applied, and the resulting ratio of peat bog water in streams was incorporated into a hydrological model. The mean peat bog contribution during baseflow ranged from 33.4% during the cold season to 48.9% during the warm season, while during runoff events, the contribution reached over 83%. The simulated water balance results showed a higher actual evapotranspiration on the mineral hillslope, which suggests a higher total runoff from the peat bog (1523 versus 1327 mm/year on the mineral hillslope). The results of this study enable more reliable modelling assessments of peatland reactions to climate change. [ABSTRACT FROM AUTHOR]

Detecting the concrete crack depth has always been a technical problem. The traditional detection methods，which are based on stress wave theory, have limitations such as low accuracy, complex operation, time-consuming and laborious procedures. This paper proposes a new method based on the combination of tracer and hand-held radar to better complete this task. Its main procedures include firstly spreading tracer diffusion to the bottom of the crack propagation, and then mapping the location of the air-tracer interface by radar waves, thus visualising the crack depth information. This paper elaborates the detection principle of this new method, carried out the feasibility numerical analysis and simulation verification. Also, the concrete standard crack specimens were made, together with relevant experimental researches. As to the feasibility of the method, it is verified by using common distilled water and saturated sodium chloride solution as tracers. The detection effects of these two tracers are compared and analysed by comparing the test data with the actual depth of the specimen. This research innovatively applies tracers to actively improve the electrical ability of concrete cracks, and then uses radar to detect the electrical distribution of cracks, realising the visual detection of crack depth. [ABSTRACT FROM AUTHOR]

In-situ tracer experiment is considered an effective means of understanding the migration characteristics of groundwater solutes under actual underground environments. The authors have developed tracer test equipment applicable to mainly fractured rock masses, and methods for evaluating experimental results. To confirm their usefulness, a tracer experiment was conducted for a single fracture in a granitic rock mass at the Mizunami Underground Research Laboratory. A numerical analysis was performed for the breakthrough curves obtained from the experiment. As a result, we were able to estimate the solute transport characteristics of the target fracture, including the aperture, the dispersion length, and the sorption coefficients of the sorbing tracers on the fracture surface and the rock matrix. Batch sorption tests were also conducted for rock samples collected at the test site. The differences between the sorption coefficients estimated from in-situ tracer tests and those obtained from batch tests were shown for Toki granite. [ABSTRACT FROM AUTHOR]

Background: Both in clinical routine and in preclinical research, the established standard procedure for the final purification of radiometal-labeled peptide radiopharmaceuticals is cartridge-based reversed-phase (RP) solid phase extraction (SPE). It allows the rapid and quantitative separation of the radiolabeled peptide from hydrophilic impurities and easy integration into automated synthesis procedures. However, product elution from RP cartridges necessitates the use of organic solvents and product recovery is sometimes limited. Thus, an alternative purification method based on commercially available size exclusion cartridges was investigated. Results: Since most peptide radiopharmaceuticals have a molecular weight > 1 kDa, Sephadex G10 cartridges with a molecular size cut-off of 700 Da were used for the final purification of a broad palette of 68Ga-, 64Cu- and 99mTc-labeled experimental peptide radiotracers as well as the clinically relevant ligand PSMA-617. Results (radiochemical purity (RCP, determined by ITLC), recovery from the solid support) were compared to the respective standard RP-SPE method. Generally, retention of unreacted 68Ga, 64Cu and 99mTc salts on the G10 cartridges was quantitative up to the specified elution volume (1.2 mL) for 68Ga and 99mTc and 99.6% for 64Cu. Even at increased elution volumes of 1.5-2 mL, RCPs of the eluted 68Ga- and 99mTc -radiopeptides were > 99%. For all peptides with a molecular weight ≥ 2 kDa, product recovery from the G10 cartridges was consistently > 85% upon respective adjustment of the elution volume. Product recovery was lowest for [68Ga]Ga-PSMA-617 (67%, 1.2 mL to 84%, 2 mL). The pH of the final product solution was found to be volume-dependent (1.2 mL: pH 6.3; 1.5 mL: pH 5.9; 2 mL: pH 5.5). Notably, the G10 cartridges were reused up to 20 times without compromising performance, and implementation of the method in an automated radiosynthesis procedure was successful. Conclusions: Overall, size exclusion purification yielded all peptide radiopharmaceuticals in excellent radiochemical purities (> 99%) in saline within 10–12 min. Although product recovery is marginally inferior to classical SPE purifications, this method has the advantage of completely avoiding organic solvents and representing a cost-effective, easy-to-implement purification approach for automated radiotracer synthesis. [ABSTRACT FROM AUTHOR]

The study focuses on the application range of nitrous oxide as a hold-up time marker in supercritical fluid chromatography (SFC). This compound has been suggested a decade ago to be used as unretained marker, something that the field of SFC was missing for a long time, since its beneficial properties make it an ideal candidate as hold-up time marker. Determination of the hold-up volume and actual volumetric flow rates have always been problematic in SFC due to the compressibility of carbon dioxide and one part of this is the difficulty of hold-up time measurements. Depending on the mobile phase, different methods have been used to measure the hold-up time with varying results. Nitrous oxide and other molecules have been compared in different conditions, mobile phases and stationary phases. In all cases, nitrous oxide gave the lowest elution times. However, detection was difficult in mobile phases containing 10% or more of organic modifier, because most solvents mask the signal of nitrous oxide. Interestingly, the choice of stationary phase also had a slight effect on detection, while different pressure and temperature settings affected each compound in a different manner. [ABSTRACT FROM AUTHOR]

Tracer testing in reservoir formations is utilised to determine residual oil saturation as part of optimum hydrocarbon production. Here, we present a novel detection method of liquid organic compounds by monodisperse SiO2 nanoparticles (NPs) containing two luminophores, a EuIII:EDTA complex and a newly synthesised fluorophore based on the organic boron‐dipyrromethene (BODIPY)‐moiety. The particles exhibited stable EuIII PL emission intensity with a long lifetime in aqueous dispersion. The fluorescence of the BODIPY was also preserved in the aqueous environment. The ratiometric PL detection technique was demonstrated by using toluene and 1‐octanol as model compounds of crude oil. The optimal synthesis conditions were found to give NPs with a diameter of ~100 nm, which is suitable for transport through porous oil reservoir structures. The cytotoxicity of the NPs was confirmed to be very low for human lung cell and fish cell lines. These findings demonstrate the potential of the NPs to replace the hazardous chemicals used to estimate the residual oil saturation. Moreover, the ratiometric PL detection technique is anticipated to be of benefit in other fields, such as biotechnology, medical diagnostics, and environmental monitoring, where a reliable and safe detection of a liquid organic phase is needed. [ABSTRACT FROM AUTHOR]

Simple Summary: The transfer of a target directly from pigs or indirectly from the environment into pen-based oral fluid samples was documented using a fluorescent tracer (red food coloring). Pens of ~30, ~60, and ~125 14-week-old pigs (32 pens/size) on commercial swine farms received one of two treatments: (1) pig exposure, i.e., ~3.5 mL of tracer solution sprayed into the mouth of 10% of the pigs in the pen; (2) environmental exposure, i.e., 20 mL of tracer solution was poured on the floor in the center of the pen. Oral fluids collected one day prior to treatment (baseline fluorescence control) and immediately after treatment were tested for fluorescence. Data were evaluated by receiver operating characteristic (ROC) analysis, with Youden's J statistic used to set a threshold. Pretreatment oral fluid samples with fluorescence responses above the ROC threshold were removed from further analysis (7 of 96 samples). Analysis of post-treatment samples showed detectable levels of red food coloring in oral fluid samples from 78 of 89 pens (87.6%), including 43 of 47 (91.5%) pens in which pigs were directly exposed and 35 of 42 (83.3%) pens in which the tracer was placed in the environment. Thus, oral fluid samples contain both pig-derived and environmental targets. Laboratory methods for detecting specific pathogens in oral fluids are widely reported, but there is little research on the oral fluid sampling process itself. In this study, a fluorescent tracer (diluted red food coloring) was used to test the transfer of a target directly from pigs or indirectly from the environment to pen-based oral fluid samples. Pens of ~30, ~60, and ~125 14-week-old pigs (32 pens/size) on commercial swine farms received one of two treatments: (1) pig exposure, i.e., ~3.5 mL of tracer solution sprayed into the mouth of 10% of the pigs in the pen; (2) environmental exposure, i.e., 20 mL of tracer solution was poured on the floor in the center of the pen. Oral fluids collected one day prior to treatment (baseline fluorescence control) and immediately after treatment were tested for fluorescence. Data were evaluated by receiver operating characteristic (ROC) analysis, with Youden's J statistic used to set a threshold. Pretreatment oral fluid samples with fluorescence responses above the ROC threshold were removed from further analysis (7 of 96 samples). Based on the ROC analyses, oral fluid samples from 78 of 89 pens (87.6%), contained red food coloring, including 43 of 47 (91.5%) pens receiving pig exposure and 35 of 42 (83.3%) pens receiving environmental exposure. Thus, oral fluid samples contain both pig-derived and environmental targets. This methodology provides a safe and quantifiable method to evaluate oral fluid sampling vis-à-vis pen behavior, pen size, sampling protocol, and target distribution in the pen. [ABSTRACT FROM AUTHOR]

The eastern coast of India, particularly near the Rushikulya River Bay, has several industries, port and urban settlements, which makes it important to study the dissolved radon concentration in the groundwater as well as in the seawater of this area. In the present study, 20 samples (9 groundwater and 11 seawater samples) were analysed using the AlphaGUARD radon monitor for the naturally occurring 222Rn. The study reveals that radon concentration in the groundwater is higher, which varies between 631 and 3142 Bq m−3 in comparison with the radon concentration in coastal waters that have a range between 160 and 289 Bq m−3. The difference in the concentration of radon in the shallow groundwater and the seawater shows that proper accounting for radon in the system will lead to quantification of the submarine groundwater discharge in this coastal region. [ABSTRACT FROM AUTHOR]

Copyright of Acta Petrologica et Mineralogica / Yanshi Kuangwuxue Zazhi is the property of Acta Petrologica et Mineralogica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Petroleum Geology & Recovery Efficiency is the property of Petroleum Geology & Recovery Efficiency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Immunotherapy targeted to immune checkpoint inhibitors, such as the program cell death receptor (PD-1) and its ligand (PD-L1), has revolutionized cancer treatment. However, it is now well-known that PD-1/PD-L1 immunotherapy response is inconsistent among patients. The current challenge is to customize treatment regimens per patient, which could be possible if the PD-1/PD-L1 expression and dynamic landscape are known. With positron emission tomography (PET) imaging, it is possible to image these immune targets non-invasively and system-wide during therapy. A successful PET imaging tracer should meet specific criteria concerning target affinity, specificity, clearance rate and target-specific uptake, to name a few. The structural profile of such a tracer will define its properties and can be used to optimize tracers in development and design new ones. Currently, a range of PD-1/PD-L1-targeting PET tracers are available from different molecular categories that have shown impressive preclinical and clinical results, each with its own advantages and disadvantages. This review will provide an overview of current PET tracers targeting the PD-1/PD-L1 axis. Antibody, peptide, and antibody fragment tracers will be discussed with respect to their molecular characteristics and binding properties and ways to optimize them.

Water transit time is now a standard measure in catchment hydrological and ecohydrological research. The last comprehensive review of transit time modeling approaches was published 15+ years ago. But since then the field has largely expanded with new data, theory and applications. Here, we review these new developments with focus on water-age-balance approaches and data-based approaches. We discuss and compare methods including StorAge-Selection functions, well/partially mixed compartments, water age tracking through spatially distributed models, direct transit time estimates from controlled experiments, young water fractions, and ensemble hydrograph separation. We unify some of the heterogeneity in the literature that has crept in with these many new approaches, in an attempt to clarify the key differences and similarities among them. Finally, we point to open questions in transit time research, including what we still need from theory, models, field work, and community practice.

Socioeconomic and environmental losses caused by water erosion have highlighted the importance of quantifying and understanding the dynamics of soil redistribution in the landscape to develop effective soil management practices. Several methods are applied to estimate erosion/deposition rates and identify sources of sediments, among them, the one that uses rare earth elements (REE) as a tracer stands out. However, an alternative not yet explored that can benefit the accuracy of the estimates provided by the method is using a tracer containing a chemical signature composed of more than one REE. The present study aimed to evaluate the performance of a new water erosion tracer based on montmorillonite labeled with rare earth elements (La40-MMT). The innovative aspects of this La40-MMT tracer include its highly stable multi-chemical signature (Nd3+, La3+, and Pr3+), which enhances tracer detection in the environment, and its low production cost due to the use of an industrial residue in the synthesis process. The tracer was evaluated for a typical soil of the Cerrado biome, using a natural rainfall field-scale plot - NRFP (5 m × 20 m) and a physical predictive erosion model (WEPP). The results showed that the La40-MMT tracer could be used to estimate erosion/deposition rates, with agreement between the values observed with the tracer and the WEPP model. Thus, this study confirmed the great potential of La40-MMT as a tool to identify patterns of soil redistribution at the field scale and aid in the validation of erosion models.

This descriptive study aimed to determine the status and profile of Bachelor of Arts in Community Development (BACD) graduates of Iloilo Science and Technology University (ISAT U) 2019-2021. The data was gathered using a researcher-made, properly validated questionnaire. The researcher used Google Forms to gather data. Frequency counts and percentages were utilized as descriptive statistical tools. Data revealed that most of the BACD graduates are female, residing in towns, single, and have not taken examinations for career advancements. Most of them have not pursued graduate education. The study revealed that BACD graduates 2019-2021 have high employment rates and were able to land a job after graduation. The majority of the graduates are employed in the private sector and are holding permanent and temporary positions. Many of the graduates hold high-level positions, while others engage in social work. Most of the graduates find their job as walk-in applicants and through recommendations and referrals. Communication skills, organizing skills, and personal relations have helped the graduates find a job. Strengthening the services of the University Placement office and enhancement to the curricular structure are advanced by this study. To increase their employment prospects, it is also suggested that BACD students be exposed to several government agencies during their fieldwork and OJT. The graduates are highly encouraged to pursue graduate studies and relevant training for career enhancement. It also recommended to continue the conduct of tracer study. [ABSTRACT FROM AUTHOR]

Sulfur hexafluoride (SF6) is the reference tracer gas in many international standards for characterizing respiratory protective devices (RPD), fume cupboards, building ventilations, and other installations. However, due to its significant impact on global warming, its use is becoming increasingly restrictive. Krypton 84 (Kr) was chosen to be a possible replacement based on theoretical and practical criteria for the properties that a substitute gas should possess. While compliance with these criteria is generally sufficient to guarantee the reliability of the choice, it is essential in the case of widespread use such as a standard to validate experimentally that this tracer has the same behavior as SF6. In this regard, numerous tests have been carried out to characterize the face leakage of RPD and the rupture of containment of fume cupboards performance tests under different operating conditions. The results obtained are identical with both tracers and lead us to propose the use of Kr as a new reference gas in standards for which SF6 was used. [ABSTRACT FROM AUTHOR]

Copyright of Hipogrifo: revista de literatura y cultura del siglo de oro is the property of Hipogrifo: revista de literatura y cultura del siglo de oro and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Bell Test (ASTM‐D1693) is commonly used to accelerate part failure in order to evaluate resin selection for applications like piping and tanks where environmental stress cracking is possible, even though the method tends to offer less than desirable repeatability. The working hypothesis for this new study with polyethylenes was that the variability seen in failure times may be attributed to a higher sensitivity of the phase morphology primarily at or near the surfaces of a notch than more commonly referenced bulk descriptors of a polymer, affecting stresses and the localized absorption of the preferred stress cracking agent. Using an organic dye tracer to monitor penetration of stress cracking agent into the polymer along with image analysis for the notch dimensions and a load cell, the local aspects of the mechanism were evaluated for up to four grades of polyethylene of varying crystallinity. By this detailed analysis, it was revealed that for failure to occur by ESC, influences in the polymer by absorption of the stress cracking agent preceded the changes in stresses in the specimen, contrary to original expectation. There was an imminent rate increase in both stresses and notch expansion once absorption of the surfactant reached a critical concentration. This critical nature was shown to be dependent on the crystallinity of the polymer under observation, considering the size/arrangement of crystals present and entanglements formed through the amorphous contents to dictate the rate by which IGEPAL can be absorbed into a polyethylene specimen. The results of this study validate the need for greater focus on polymer properties at the notch rather than the bulk of the specimen, though more techniques for providing analysis of these properties at the notch surfaces are needed for future improvements to the mechanism. Highlights: Bromocresol dye acts as a novel visualization aid in tracking IGEPAL CO‐630 sorptionCrystallinity was related to a plasticization threshold for absorption of IGEPALAccelerated increase in internal stresses follow absorption.Variability of the Bell Test was related to crystalline properties at the notch [ABSTRACT FROM AUTHOR]

Cadmium (Cd) is one of the environmental pollutants contaminated in our food. Several previous reports showed that rice polishing cannot be efficient to reduce Cd content in white rice, implying the characteristic Cd distribution in rice grain. However, Cd distribution has not been fully elucidated so far. Herein, 109Cd radiotracer experiment was performed using the rice seedlings at various time points after flowering to obtain autoradiographs of the brown rice to visually understand the Cd transport and distribution during the grain‐filling process. It was shown that 109Cd accumulated in the outermost area of the brown rice, and also in the middle part of the starchy endosperm, resulting in the appearance of the double circle distribution pattern, which was not observed in the autoradiographs of 65Zn. The inner circle of 109Cd located around the center of the endosperm was developed particularly at around 8 and 10 days after flowering. After this period, 109Cd started to deposit at the outer part of the endosperm, which was also found in the autoradiograph of 14C‐sucrose. Considering the physiology of grain development, the contribution of water transport and protein synthesis in the endosperm on the characteristic Cd distribution pattern was hypothesized. [ABSTRACT FROM AUTHOR]

Background: The government has prioritized controlling the spread of the COVID-19 virus in North Musi Rawas Regency by strengthening surveillance efforts. One of the strategies employed to enhance the surveillance system is contact tracing using the Silacak application. Community members are involved as tracers utilizing the Silacak application. Objective: This activity aims to improve COVID-19 contact tracing by community tracers using the Silacak application in North Musi Rawas District. Method: This community service activity involves socialization, application training, and direct contact tracing by tracers utilizing the Silacak application. It follows a health program management approach, encompassing initiation, planning, implementation, monitoring, and evaluation phases. Results: Socialization and application training took place on August 24, 2021, at Sederhana restaurant hall in Muara Rupit Village, Sumatera, from 08:00 to 12:30 WIB. Tracer monitoring occurred from August to December 2021. The 69 participants included health cadres, Babinsa, and Bhabinkamtibmas. The results indicate that the Surulangun Puskesmas tracer conducted the highest percentage of close contact monitoring, reaching 54.14% of the expected number, with 51.49% of close contacts monitored. Each health center monitored fewer close contacts compared to the previous month. Conclusion: Tracer performance in close contact monitoring using the Silacak application has not been optimal due to various challenges, including tracer comprehension, signal interference during data entry, additional responsibilities for Babinsa and Bhabinkamtibmas, and negative community responses. [ABSTRACT FROM AUTHOR]

Preferential flow is ubiquitous in soils, and it affects water infiltration, runoff, and contaminant transport. Undisturbed soil lysimeters (n = 10; 900 cm2) were collected from an agricultural field to quantify the effect of climate, soil moisture, connectivity, and agricultural practices on water transport through the shallow vadose zone. A series of 10 rainfall simulations was conducted on each lysimeter (n = 100 events) and data were analysed within a framework of five case studies where we assessed the impact of rainfall intensity (n = 30 events), soil moisture (n = 28), and tillage (n = 21). Three lysimeters that had near‐zero flow initially were modified to investigate dynamics of direct surface connectivity through an artificial macropore in which we assessed the impacts of soil moisture (n = 12) and subsequent disruption via tillage (n = 9). Stable water isotopes were used to separate leachate into event (Qe) and pre‐event water (Qpe). Results showed that event water transport in leachate was not affected by rainfall intensity (Qe/Q = 49% ± 21% to 50% ± 24%); however, event water decreased from 65% ± 5% to 23% ± 28% with increasing soil moisture. Lysimeters with artificial macropores resulted in leachate that was nearly all event water (85% ± 12% to 92% ± 4%) irrespective of soil moisture. Tillage decreased event water transport for both lysimeters with and without an artificial macropore by ~30%. Findings show how varying initial and boundary conditions produce a continuum of preferential flow. Water and tracer flux data collected in the current study are therefore essential for predicting conditions with high relevance of preferential flow and contaminant transport when assessing or modelling long‐term hydrographs where these conditions are only met during a small proportion of the flow time. [ABSTRACT FROM AUTHOR]

The Greenland Ice Sheet is losing mass at an accelerating pace, increasing its contribution to the freshwater input into the Nordic Seas and the subpolar North Atlantic. It has been proposed that this increased freshwater may impact the Atlantic Meridional Overturning Circulation by affecting the stratification of the convective regions of the North Atlantic and Nordic Seas. Observations of the transformation and pathways of meltwater from the Greenland Ice Sheet on the continental shelf and in the gyre interior, however, are lacking. Here, we report on noble gas derived observations of submarine meltwater distribution and transports in the East and West Greenland Current Systems of southern Greenland and around Cape Farewell. In southeast Greenland, submarine meltwater is concentrated in the East Greenland Coastal Current core with maximum concentrations of 0.8%, thus significantly diluted relative to fjord observations. It is found in water with density ranges from 1,024 to 1027.2 kg m−3 and salinity from 30.6 to 34, which extends as deep as 250 m and as far offshore as 60 km on the Greenland shelf. Submarine meltwater transport on the shelf averages 5.0 ± 1.6 mSv which, if representative of the mean annual transport, represents 60%–80% of the total solid ice discharge from East Greenland and suggests relatively little offshore export of meltwater east and upstream of Cape Farewell. The location of the meltwater transport maximum shifts toward the shelfbreak around Cape Farewell, positioning the meltwater for offshore flux in regions of known cross‐shelf exchange along the West Greenland coast. Plain Language Summary: The Greenland Ice Sheet is losing a lot of ice very quickly and this is causing more lightweight freshwater to flow into the North Atlantic Ocean. This extra freshwater could possibly influence the way that the surface and interior of the ocean interact, impacting global ocean currents. We do not have enough information about how the ice that is melting from Greenland is affecting the ocean, in part because we do not have many tools to observe where the meltwater goes. In this work, we made measurements with the best tools available to follow the ice melted from marine terminating glaciers as it travels around Greenland. We were able to make some of the most comprehensive direct measurements of the oceanic pathways of glacial meltwater in coastal Greenland. We found that the freshwater from Greenlandic glacier's submarine melted ice is not very concentrated when it gets to the ocean, but it does go deep and, at first, not too far away from the shore. The Greenland meltwater stays close to shore along the east coast up to Cape Farewell. However, meltwater moves farther from shore after that and may mix out into the open ocean from there. Key Points: Direct measurements of the pathways and fluxes of glacial meltwater in coastal GreenlandLittle offshore export of meltwater east and upstream of Cape FarewellMeltwater moves offshore toward shelfbreak around Cape Farewell [ABSTRACT FROM AUTHOR]