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To accurately characterize the geometric features in the repair of Ti-6Al-4 V alloy, a laser cladding mathematical model was developed and experimentally validated. The model employed a quartic polynomial function to analyze the geometric features of the clad layer, investigating correlations among deposition angle, clad layer width, melt pool depth, and clad layer area. Additionally, it utilized a quadratic polynomial function to characterize the geometric profile of the melt pool, establishing relationships involving clad layer width, melt pool depth, and melt pool area simultaneously. By means of the areas of the cladding layer and the melt pool, the value of the dilution rate can be obtained. Subsequently, the measured and predicted values of the clad layer, melt pool, and dilution rate were compared. The results demonstrated the mathematical model's capability to accurately forecast geometric features in laser cladding. Furthermore, an orthogonal experiment was conducted to investigate how process parameters—laser power, scanning speed, and powder feeding rate—affect the geometric dimensions (height, width, and melt pool depth) of single-pass, single-layer cladding, and to elucidate the underlying reasons. These investigations offered theoretical insights and practical guidelines for controlling the clad layer, melt pool, and dilution rate. [ABSTRACT FROM AUTHOR]

Fish biologists have long assumed a link between intestinal length and diet, and relative gut length or Zihler's index are often used to classify species into trophic groups. This has been done for specific fish taxa or specific ecosystems, but not for a global fish dataset. Here, we assess these relationships across a dataset of 468 fish species (254 marine, 191 freshwater, and 23 that occupy both habitats) in relation to body mass and fish length. Herbivores had significantly relatively stouter bodies and longer intestines than omni- and faunivores. Among faunivores, corallivores had longer intestines than invertivores, with piscivores having the shortest. There were no detectable differences between herbivore groups, possibly due to insufficient understanding of herbivorous fish diets. We propose that reasons for long intestines in fish include (i) difficult-to-digest items that require a symbiotic microbiome, and (ii) the dilution of easily digestible compounds with indigestible material (e.g., sand, wood, exoskeleton). Intestinal indices differed significantly between dietary groups, but there was substantial group overlap. Counter-intuitively, in the largest dataset, marine species had significantly shorter intestines than freshwater fish. These results put fish together with mammals as vertebrate taxa with clear convergence in intestine length in association with trophic level, in contrast to reptiles and birds, even if the peculiar feeding ecology of herbivorous fish is probably more varied than that of mammalian herbivores. [ABSTRACT FROM AUTHOR]

The optical properties of Carbon dot (CD) solution significantly change on dilution. Herein, the effect of dilution on the optical properties of folic acid-derived CD was meticulously analyzed using absorption and photoluminescence (PL) spectroscopy. Absorption spectra of as-prepared CD solution consist of four overlapping yet discernable absorption bands centered at ~ 249, 302, 348, and 330 nm, respectively, attributed to originate from the π-π* transition and n-π* transitions and/or surface states. As the CD solution is diluted from 100 to 5%, these four absorption bands become more resolved. Moreover, we observed a blueshift of ~ 30 nm for the transitions at ~ 302 nm due to surface state with dilution up to 20% CD concentration. This is attributed to the decrease in the interaction between surface states due to the increase in the interparticle distance with dilution. PL emission from the as-prepared CD solution is centered at 463 nm and is asymmetric. This can be resolved into three components centered at 446 nm (intense), 474 nm (intense) and 508 nm (weak) respectively. With dilution, the PL intensity corresponding to the 463 nm emission seems to increase up to an optimum concentration of 15% CD and then decreases. The high concentration effectively quenches the luminescence through inner filter effect which is evident from the overlapping of absorption peak with the peak in the excitation spectrum together with no notable change in the average decay time. The decrease in the percentage of overlapping area of the absorption and excitation spectra with dilution causes the reduction of inner filter effect and enhances the luminescence for diluted solutions. Furthermore, we found that the surface states become more dominant in the contribution of luminescence of CD, whose influence diminishes in extremely diluted solutions, thereby the intensity decrease below 15% dilution. [ABSTRACT FROM AUTHOR]

A simple and effective heuristic approach was developed and validated to predict the concentration of non-relevant metabolites (nrM) of pesticides in groundwater and drinking water resources based on the simulated concentrations in leachate as used in product authorizations. The evaluation of extensive monitoring data for 50 nrM has demonstrated that the heuristic has a high predictive performance, i.e., concentrations of < 10 µg/l in shallow leachate in the unsaturated zone of the soil in 1 m depth are protective of 1 µg/l in groundwater and raw water in 98 % of cases (49/50 nrM). The reason for the excellent predictive power of the heuristic approach is the large concentration attenuation from leachate to groundwater and to raw water, which was determined to be, on average, 25- and 45-fold, respectively. [ABSTRACT FROM AUTHOR]

Detecting life has driven research and exploration for centuries, but recent attempts to compile and generate a framework that summarizes life features, aimed to develop strategies for life detection missions beyond planet Earth, have disregarded a key life feature: behavior. Yet, some behaviors such as biomineralization or motility have occasionally been proposed as biosignatures to detect life. Here, we capitalize on a specific taxis' motility behavior, magnetotaxis, to experimentally provide insights in support of behavior as an unambiguous, sensitive biosignature, and magnetic forces as a prescreening option. Using a magnetotactic bacterial species, Magnetospirillum magneticum, we conducted a lab sensitivity experiment comparing PCR with the hanging drop behavioral assay, using a dilution series. The hanging drop behavioral assay visually shows the motility of MTB toward magnetic poles. Our findings reveal that the behavioral assay exhibits higher sensitivity in the detection of M. magneticum when compared to the established PCR protocol. While both methods present similar detection sensitivities at high concentrations, at ≥ 10–7 fold dilutions, the behavioral method proved more sensitive. The behavioral method can detect bacteria even when samples are diluted at 10–9. Comparable results were obtained with environmental samples from the Hula Valley. We propose behavioral cues as valuable biosignatures in the ongoing efforts of life detection in unexplored aquatic habitats on Earth and to stimulate and support discussions about how to detect extant life beyond Earth. Generic and robust behavioral assays can represent a methodological revolution. [ABSTRACT FROM AUTHOR]

Objective: Arterial-phase artifacts are gadoxetic acid (GA)–enhanced MRI's major drawback, ranging from 5 to 39%. We evaluate the effect of dilution and slow injection of GA using automated fluoroscopic triggering on liver MRI arterial-phase (AP) acquisition timing, artifact frequency, and lesion visibility. Methods and materials: Saline-diluted 1:1 GA was injected at 1 ml/s into 1413 patients for 3 T liver MRI. Initially, one senior abdominal radiologist, i.e., principal investigator (PI), assessed all MR exams and compared them to previous and follow-up images, as well as the radiology report on record, determining the standard of reference for lesion detection and characterization. Then, three other readers independently evaluated the AP images for artifact type (truncation (TA), transient severe motion (TSM) or mixed), artifact severity (on a 5-point scale), acquisition timing (on a 4-point scale) and visibility (on a 5-point scale) of hypervascular lesions ≥ 5 mm, selected by the PI. Artifact score ≥ 4 and artifact score ≤ 3 were considered significant and non-significant artifacts, respectively. Results: Of the 1413 exams, diagnostic-quality arterial-phase images included 1100 (77.8%) without artifacts, 220 (15.6%) with minimal, and 77 (5.4%) with moderate artifacts. Only 16 exams (1.1%) had significant artifacts, 13 (0.9%) with severe artifacts (score 4), and three (0.2%) non-diagnostic artifacts (score 5). AP acquisition timing was optimal in 1369 (96.8%) exams. Of the 449 AP hypervascular lesions, 432 (96.2%) were detected. Conclusion: Combined dilution and slow injection of GA with MR results in well-timed arterial-phase images in 96.8% and a reduction of exams with significant artifacts to 1.1%. Clinical relevance statement: Hypervascular lesions, in particular HCC detection, hinge on arterial-phase hyperenhancement, making well-timed, artifact-free arterial-phase images a prerequisite for accurate diagnosis. Saline dilution 1:1, slow injection (1 ml/s), and automated bolus triggering reduce artifacts and optimize acquisition timing. Key Points: • There was substantial agreement among the three readers regarding the presence and type of arterial-phase (AP) artifacts, acquisition timing, and lesion visibility. • Impaired AP hypervascular lesion visibility occurred in 17 (3.8%) cases; in eight lesions due to mistiming and in nine lesions due to significant artifacts. • When AP timing was suboptimal, it was too late in 40 exams (3%) and too early in 4 exams (0.2%) of exams. [ABSTRACT FROM AUTHOR]

The cooling capacity of a typical dilution refrigerator is mainly determined by the circulating flow of the He-3 in the system, which is usually realized by the external circulation pump. In order to increase the concentration of circulating He-3, the still often take the orifice structure to limit the influence of the superfluid helium film, and this structure will also have a certain impact on the flow rate of He-3. This paper summarizes the flow rate models of each part of the orifice structure, and establishes a model related to the influence of pumping speed and the diameter of orifice on the flow rate of circulating He-3. The relationship between pumping speed and flow rate is developed and the relation is divided into three phases for detailed analysis. It is found that the flow rate and the concentration of circulating He-3 increase first and then decrease with the increasing diameter of orifice at a certain pumping speed, and the possible reasons for this phenomenon are analyzed. The results indicate that there is an optimal orifice diameter at a determined pumping speed. [ABSTRACT FROM AUTHOR]

We investigate the zero-temperature hysteresis characteristics of the diluted random field 3-state clock model under a cyclic driving field with zero frequency. This analysis is conducted in the presence of two types of quenched random fields within the mean field approximation. The influence of dilution on the hysteretic response of the model at moderate concentration levels is observed to be contingent on the particular form of disorder. Following this, simulations on a simple cubic lattice are performed for a comparative analysis with mean field predictions. [ABSTRACT FROM AUTHOR]

This study addresses the effect of using animal excreta on the nutritional content of forages, focusing on macro- and micro-element concentrations (nitrogen; N, phosphorus; P, sulphur; S, copper; Cu, zinc; Zn, manganese; Mn, selenium; Se) from animal feed to excreta, soil, and plants. Data were collected from pot and field trials using separate applications of sheep or cattle urine and faeces. Key findings indicate that soil organic carbon (SOC) and the type of excreta significantly influences nutrient uptake by forages, with varied responses among the seven elements defined above. Although urine contributes fewer micronutrients compared to faeces (as applied at a natural volume/mass basis, respectively), it notably improves forage yield and micronutrient accumulation, thus potentially delivering positive consequences at the farm level regarding economic performance and soil fertility when swards upon clayey soil types receive said urine in temperate agro-climatic regions (i.e., South West England in the current context). In contrast, faeces application in isolation hinders Se and Mn uptake, once again potentially delivering unintended consequences such as micronutrient deficiencies in areas of high faeces deposition. As it is unlikely that (b)ovine grazing fields will receive either urine or faeces in isolation, we also explored combined applications of both excreta types which demonstrates synergistic effects on N, Cu, and Zn uptake, with either synergistic or dilution effects being observed for P and S, depending largely on SOC levels. Additionally, interactions between excreta types can result in dilution or antagonistic effects on Mn and Se uptake. Notably, high SOC combined with faeces reduces Mn and Se in forages, raising concerns for grazed ruminant systems under certain biotic situations, e.g., due to insufficient soil Se levels typically observed in UK pastures for livestock growth. These findings underscore the importance of considering SOC and excreta nutritional composition when designing forage management to optimize nutrient uptake. It should be noted that these findings have potential ramifications for broader studies of sustainable agriculture through system-scale analyses, as the granularity of results reported herein elucidate gaps in knowledge which could affect, both positively and negatively, the interpretation of model-based environmental impact assessments of cattle and sheep production (e.g., in the case of increased yields [beneficial] or the requirement of additional synthetic supplementation [detrimental]). [ABSTRACT FROM AUTHOR]

The GMAW process with rotating electrode (GMAW-RE) process is an advance of the GMAW process, with the rotational movement of the wire-electrode providing more homogeneous weld bead profiles suitable to weld claddings. Besides the lower dilution, it can contribute to achieving the main geometric parameters, reinforcement, and penetration, useful to acceptable mechanical and corrosion properties using less volume of deposited metal. Based on these characteristics, this work evaluates the feasibility of the GMAW-RE to deposit a single layer of Inconel 625 weld cladding with suitable properties. Initially, the effect of the diameter and rotation frequency was investigated through single layer claddings with three welding passes. Afterward, the properties of the single and double layer claddings using the selected parameters were studied. The microstructure was observed by electron microscopy while tension, bending, and microhardness tests evaluated the mechanical properties. Electrochemical corrosion tests were conducted to obtain the pitting potential and critical pitting temperature. The results showed a homogeneous weld penetration profile, low dilution ratio, and adequate reinforcement. The austenitic microstructure containing a low amount of secondary phases provided mechanical and corrosion resistance equivalent to those obtained by low dilution processes and base metals. These results indicate that the GMAW-RE process has the potential to be an alternative for claddings used in the oil and gas industry because single layer deposits can show acceptable performance. [ABSTRACT FROM AUTHOR]

Submerged cultivation of edible filamentous fungi (Agaricomycetes) in bioreactors enables maximum mass transfer of nutrients and has the potential to increase the volumetric productivity of fungal biomass compared to solid state cultivation. These aspects are paramount if one wants to increase the range of bioactives (e.g. glucans) in convenient time frames. In this study, Trametes versicolor (M9911) outperformed four other Agaricomycetes tested strains (during batch cultivations in an airlift bioreactor). This strain was therefore further tested in semi-continuous cultivation. Continuous and semi-continuous cultivations (driven by the dilution rate, D) are the preferred bioprocess strategies for biomass production. We examined the semi-continuous cultivation of T. versicolor at dilution rates between 0.02 and 0.1 h−1. A maximum volumetric productivity of 0.87 g/L/h was obtained with a D of 0.1 h−1 but with a lower total biomass production (cell dry weight, CDW 8.7 g/L) than the one obtained at lower dilution rates (12.3 g/L at D of 0.04 and vs 13.4 g/L, at a D of 0.02 h−1). However, growth at a D of 0.1 h−1 resulted in a very short fermentation (18 h) which terminated due to washout (the specific D exceeded the maximum growth rate of the fungal biomass). At a D of 0.04 h−1, a CDW of 12.3 g/L was achieved without compromising the total residence time (184 h) of the fermentation. While the D of 0.04 h−1 and 0.07 h−1 achieved comparable volumetric productivities (0.5 g/L/h), the total duration of the fermentation at D of 0.07 h−1 was only 85 h. The highest glucan content of cells (27.8 as percentage of CDW) was obtained at a D of 0.07 h−1, while the lowest glucan content was observed in T. versicolor cells grown at a D of 0.02 h−1. Key points: • The highest reported volumetric productivity for fungal biomass was 0.87 g/L/h. • Semi-continuous fermentation at D of 0.02 h−1 resulted in 13.4 g/L of fungal biomass. • Semi-continuous fermentation at D of 0.07 h−1 resulted in fungal biomass with 28% of total glucans. [ABSTRACT FROM AUTHOR]

Increase in transendothelial water permeability is an essential etiological factor in a variety of diseases like edema and shock. Despite the high clinical relevance, there has been no precise method to detect transendothelial water flow until now. The deuterium oxide (D2O) dilution method, already established for measuring transepithelial water transport, was used to precisely determine the transendothelial water permeability. It detected appropriate transendothelial water flow induced by different hydrostatic forces. This was shown in four different endothelial cell types. The general experimental setup was verified by gravimetry and absorbance spectroscopy. Determination of transendothelial electrical resistance (TEER) and immunocytochemical staining for proteins of the cell-cell contacts were performed to ensure that no damage to the endothelium occurred because of the measurements. Furthermore, endothelial barrier function was modulated. Measurement of transendothelial water flux was verified by measuring the TEER, the apparent permeability coefficient and the electrical capacity. The barrier-promoting substances cyclic adenosine monophosphate and iloprost reduced TEER and electrical capacity and increased permeability. This was accompanied by a reduced transendothelial water flux. In contrast, the barrier-damaging substances thrombin, histamine and bradykinin reduced TEER and electrical capacity, but increased permeability. Here, an increased water flow was shown. This newly established in vitro method for direct measurement of transendothelial water permeability was verified as a highly precise technique in various assays. The use of patient-specific endothelial cells enables individualized precision medicine in the context of basic edema research, for example regarding the development of barrier-protective pharmaceuticals. [ABSTRACT FROM AUTHOR]

Background: The losses due to the COVID-19 pandemic has led to widespread impacts on mental health. Although affective attentional processes are implicated in mental health concerns broadly, there has been limited research on the influence of COVID-19 related loss on affective attentional processes. The primary aim of this study was to investigate the impact of a COVID-19 related loss on affective attentional processes. Methods: We recruited participants through Amazon Mechanical Turk in an initial study (Study 1: n = 136) and pre-registered replication (Study 2: n = 206). To measure affective attentional processes, participants completed the Emotional Stroop Dilution Task with word stimuli that were either neutral, generally trauma-related, or specific to COVID-19. To quantify affective attentional processes, novel response-based computation with superior psychometric properties and traditional attention bias computation approaches were used. Results: Using response-based measures COVID-19 related loss was associated with greater attention capture and facilitation in response to COVID-19 specific words in Study 1. In Study 2 (pre-registered replication), we again found COVID-19 related loss was associated with high conflict attention capture and facilitation for COVID-19 related stimuli only. No associations between the two studies were replicated with the traditional approach. Conclusions: Taken together, findings from these studies suggest that experiencing a COVID-19 related loss is associated with dysregulation of affective attentional processes, specific to COVID-related stimuli. Future research should examine whether dysregulated affective attentional processes can be addressed (e.g., with attention bias modification) which may be helpful for addressing mental health concerns in the wake of COVID-19 related loss. [ABSTRACT FROM AUTHOR]

This study characterized metal contamination in the Blesbokspruit River waters, near the coal-mining town of Emalahleni in Mpumalanga, South Africa, using enrichment factors (EFs) and contamination factors (CFs). We investigated the potential of Fe and Al 'dilution factors' (stream water divided by overbank sediment concentrations) under base flow hydrological conditions to detect AMD-related trace metal contamination in the study site. Waters of the Blesbokspruit River were characterized by acidic (< 3) to near neutral (≈7) pH, high EC (up to 2240 µS/cm), high sulfate (up to 1530 mg/L), ultra-high degrees of Fe contamination and minor to moderately severe enrichment of trace metals, all of which strongly indicate that the river is affected by AMD. Fe and Al dilution factors showed moderate to strong positive correlations with dissolved trace metals (Co, Ni, Zn, Pb, Cr, and Cd), but not with Cu, which is likely more associated with kaolinite in the study area. In addition, correlation analysis showed that dilution factors were better for detecting aqueous Co and Cd, and comparable for detecting aqueous Ni, relative to stream pH and aqueous Fe and Al. Dilution factors have an advantage over stream pH and aqueous Al and Fe because, once calculated, they can be used to monitor AMD-related trace metal contamination in streams during dry seasons by using only Al and Fe content in sediments. This can be beneficial when preservation methods or storage necessary for water samples are not available. However, the robustness of dilution factors during wet seasons requires further investigation. [ABSTRACT FROM AUTHOR]

The effect of heat and momentum losses on the steady solutions admitted by the reactive Euler equations with sink/source terms is examined for stoichiometric hydrogen–oxygen mixtures. Varying degrees of nitrogen and argon dilution are considered in order to access a wide range of effective activation energies, E a,eff / R u T 0 , when using detailed thermochemistry. The main results of the study are discussed via detonation velocity-friction coefficient (D– c f ) curves. The influence of the mixture composition is assessed, and classical scaling for the prediction of the velocity deficits, D (c f,crit) / D CJ , as a function of the effective activation energy, E a,eff / R u T 0 , is revisited. Notably, a map outlining the regions where set-valued solutions exist in the E a,eff / R u T 0 -- α space is provided, with α denoting the momentum–heat loss similarity factor, a free parameter in the current study. [ABSTRACT FROM AUTHOR]

A crucial problem in the design of heat exchangers (HEx) for dilution refrigerators is thermal boundary resistances between liquid helium and substances rapidly increasing at low temperatures. In addition, thermal resistivity of liquid helium in restricted geometries also increases with decreasing temperature. To solve these problems, recently we developed the nanopore heat exchanger (NHEx), where nanoporous silicate and 75000-nm silver powder are used. Nanoporous materials have huge specific area about of 1000 m 2 /g, which is 3 orders larger compared with conventional fine silver powder sinters widely used for HExs. We have measured the Kapitza resistance of NHEx down to 22 mK and found that it is nearly 10 times smaller than that of conventional sinters with the same size. Use of 75000-nm silver powder instead of 70 nm also allows to reduce thermal resistivity of the liquid. In order to examine performance of the NHEx, quantitative evaluation is performed using numerical simulations. The result shows 3–10 times better performance of NHEx, compared with conventional HExs. [ABSTRACT FROM AUTHOR]

While the current practice in designing brine outfalls for seawater desalination plants has provided a level of protection to the coastal environment that is deemed acceptable, additional research can be pursued to further improve the state-of-the-art understanding as well as enable the integration of beneficial features introduced by the brine outfall. The present study performed both numerical simulations and laboratory experiments to investigate the mixing and spreading of an 45º inclined dense jet in coastal regions with submerged vegetation canopies at the seabed. The numerical simulations utilized the Reynolds-Averaged Navier-Stokes (RANS) equations with the standard k-ε turbulence closure and non-interactive species transport model. The experiments were performed using the technique of Planar Laser Induced Fluorescence (PLIF) for verification. The overall results showed that the mixing of the inclined dense jet is enhanced just above the top of the submerged canopy due to the presence of stem-scale wakes and increased dispersity promoted by the spatial inhomogeneity near the canopy interface. A threshold value of 0.6 for the characteristic parameter, ϕFr, where Fr is the densimetric Froude number of jets and ϕ is the canopy density, has been observed above which the dilution coefficients reach a plateau and are no longer influenced by the canopy density. Within the canopy, however, the barrier effect prevails in the mixing process leading to constrained dilution particularly with denser canopies. In particular, the concentration at the impingement region within the canopy near the bottom is observed to increase with the increase in the general canopy density. Highlights: The effects of submerged canopy on the mixing and spreading of inclined dense jets are investigated numerically and experimentally. The presence of the canopy enhances the dilution of the inclined dense jet above canopies while increase the concentration within canopies. Quantitative influence depends on the discharge characteristics of the inclined dense jet as well as the characteristics of the canopy. [ABSTRACT FROM AUTHOR]

Tribaloy™ T800, a Co-based alloy, exhibits remarkable tribological properties by virtue of its high-volume fraction of intermetallic Laves phase making it an attractive hard-facing material. Hard-facing by laser deposition results in dilution from the substrate, and thereby, the properties of the clad are altered. This paper reports the influence of processing parameters on the dilution, microstructure, and wear behaviour of Tribaloy™ T800 on AISI 316 stainless steel. A systematic set of 20 clads was deposited by varying laser power and cladding speed, keeping powder flow and spot diameter constant. While dilution decreased at lower laser powers (800 and 1000 W) with increasing cladding speed (5–20 mm s−1), at higher laser powers (1200 and 1400 W), the opposite trend was observed. The Fe intermixing from the substrate along with the cooling rate governs the volume fraction and size of the Laves phases which controls the properties of T800 clads. The clad with the least geometric dilution (5.7%) exhibits the lowest wear rate of 0.54 × 10−5 mm3 N−1 m−1, increasing to 2.88 × 10−5 mm3 N−1 m−1 as the dilution increased to 60%. [ABSTRACT FROM AUTHOR]

The availability of serology assays to measure antibodies against the SARS coronavirus 2 (SARS-CoV-2) expanded rapidly during the Covid-19 pandemic. The interchangeable use of such assays to monitor disease progression and immune protection requires their standardization, for which suitably characterized monoclonal antibody materials can be useful. The methods, based on isotope dilution mass spectrometry, to value assign the mass fraction of such a material in solution within the context of an international interlaboratory comparison study (CCQM-P216) are described. The mass fraction in solution of a humanized IgG monoclonal antibody (mAb) against the SARS-CoV-2 Spike glycoprotein in the study sample has been value assigned through a combination of liquid chromatography, isotope dilution mass spectrometry (LC-ID-MS) methods and size exclusion chromatography with UV detection (SEC-UV). The former were developed for the quantification of amino acids and proteotypic peptides as surrogate analytes of the mAb while the latter was applied for the determination of the relative monomeric mass fraction. High-resolution mass spectrometry (hrMS) allowed the molecular weight evaluation and ruled out the presence of significant impurities. Method trueness was assessed using a subclass homologous IgG1 material value assigned by amino acid analysis. The assigned mass fraction of monomeric SARS-CoV-2 IgG in solution was 390 ± 16 mg/g. The associated expanded uncertainty originated mainly from acid hydrolysis variability and Trypsin/Lys-C digestion variability and efficiency. [ABSTRACT FROM AUTHOR]

The combination of ceftazidime-avibactam (CAZ-AVI) and aztreonam (ATM) is used to treat MBL-producing Enterobacterales-related infections. The new combination aztreonam-avibactam (AZA) is currently in development. We compared results obtained with the new MIC test strip (MTS) AZA (Liofilchem) with broth microdilution method (BMD) on 41 MBL-producing Enterobacterales from 41 clinical samples. The MTS AZA was also compared to combination testing method using CAZ-AVI and ATM strips. Compared to BMD, categorical agreement (CA) was 100%. Compared with combination testing method, CA was 97.6%. The MTS AZA can be used to determine MICs levels of AZA or CAZ-AVI/ATM combinations. [ABSTRACT FROM AUTHOR]

Numerical simulations on ammonia/hydrogen/air detonation are performed using a detailed reaction model to investigate the cellular instability and detonation dynamics as a function of hydrogen content. The UT-LCS model that includes 32 species and 213 elementary reactions is used in the present simulations. The fifth-order target compact nonlinear scheme captured the unstable detonation dynamics and the complicated flow structure including the propagation of a sub-transverse wave. The simulation performed with different hydrogen dilutions shows that the detonation propagates at the Chapman–Jouguet velocity for all cases, and the cell size for the ammonia/hydrogen mixing ratio α = 0.3 becomes approximately 10 times larger than that for α = 1.0 (hydrogen/air mixture). A transverse detonation produces a finescale cellular structure on the computed maximum pressure history. This complex shock formation is similar to those of a spinning detonation and two-dimensional propane/oxygen detonation. The cellular irregularity increases with decreasing hydrogen content because ammonia destabilizes the detonation cellular structure with a reduced activation energy of more than approximately 8. [ABSTRACT FROM AUTHOR]

Low-temperature scanning probe microscopes (SPMs) are critical for the study of quantum materials and quantum information science. Due to the rising costs of helium, cryogen-free cryostats have become increasingly desirable. However, they typically suffer from comparatively worse vibrations than cryogen-based systems, necessitating the understanding and mitigation of vibrations for SPM applications. Here we demonstrate the construction of two cryogen-free dilution refrigerator SPMs with minimal modifications to the factory default and we systematically characterize their vibrational performance. We measure the absolute vibrations at the microscope stage with geophones and use both microwave impedance microscopy and a scanning single-electron transistor to independently measure tip-sample vibrations. Additionally, we implement customized filtering and thermal anchoring schemes and characterize the cooling power at the scanning stage and the tip electron temperature. This work serves as a reference to researchers interested in cryogen-free SPMs, as such characterization is not standardized in the literature or available from manufacturers. [ABSTRACT FROM AUTHOR]

Much of the work on the valuation of levered (and unlevered) warrants assumes that the volatility of the underlying state variable is constant. This paper extends the literature on warrant pricing to a more general assumption for the state variable process, the so-called constant elasticity of variance (CEV) process. The CEV model is well-known for its ability to capture some empirical observations found in the financial economics literature, namely the asymmetry between equity returns and volatility and the implied volatility skew. Using the CEV process, we are able to reduce pricing bias as the volatility becomes a function of the underlying state variable. We price European-style call warrants without restrictions on the debt maturity. When warrants have the same maturity as debt, it is possible to obtain closed-form solutions for warrants prices. When the maturity of warrants is different from the maturity of debt, prices can be computed numerically through very efficient and simple to implement valuation methodologies. [ABSTRACT FROM AUTHOR]

In the process of excavating the shaft, blasting will generate a large amount of CO, which will pollute the environment inside the shaft and jeopardize the health of the construction workers. In this study, the theoretical equation of CO distribution inside the shaft during the construction period is derived based on the diluted ventilation model. The ventilation process in the shaft under different working conditions was numerically simulated. And the grid convergence index method was used to study the independence of the grid to ensure the accuracy of the numerical simulation. The selection of the location of the duct is the main factor affecting the distribution of the flow field in the shaft. The distance between the outlet of the duct and the working face of the shaft is the main factor affecting the dilution of CO in the shaft. The flow rate of the jet ejected from the outlet of the duct is the main factor influencing the movement rate of the CO peak. The distribution functions of hazardous gases in the shaft with space and time when the shaft is ventilated by forced ventilation are derived. Based on the diameter of the shaft and the ventilation volume, the formula for estimating the ventilation time required for shaft construction was constructed. The accuracy of the formula was verified by the actual projects. The optimized ventilation measures by using the results of this study can effectively improve the construction environment in the shaft, which has certain significance for similar projects. [ABSTRACT FROM AUTHOR]

Flame self-interaction (FSI) events in Moderate or Intense Low-Oxygen Dilution (MILD) combustion of homogeneous and inhomogeneous mixtures of methane and oxidiser have been analysed using three-dimensional Direct Numerical Simulations (DNS). The simulations have been conducted at the same global equivalence ratio ( ⟨ ϕ ⟩ = 0.8 ) for different levels of O 2 concentration (dilution) and initial turbulence intensities. It has been reported that both homogeneous and inhomogeneous mixture MILD combustion cases exhibit significant occurrences of FSI events, with the peak frequency of FSI events occurring towards the burned gas side in all cases. Moreover, the frequency of FSI events increases with increasing dilution level and turbulence intensity, but the presence of mixture inhomogeneity leads to a reduction in total FSI events. In all cases, the cylindrical FSI topologies (i.e. tunnel formation and tunnel closure) were found to have a higher likelihood of occurrence compared to spherical FSI topologies (i.e. unburned and burned gas pockets). The geometries of FSI topologies were also analysed using the mean and Gaussian curvatures. It has been shown that the inward propagating spherical FSI topologies (i.e. unburned gas pockets) are associated with negative mean curvature, while outward propagating spherical FSI topologies (i.e. burned gas pockets) are associated with positive mean curvature. Moreover, tunnel formation (tunnel closure) FSI topologies predominantly exhibit either elliptic geometries with positive (negative) mean curvature or hyperbolic saddle geometries with negative (positive) mean curvature. It has been shown for the first time in MILD combustion that the mean values of kinematic restoration and dissipation terms in the transport equation of the magnitude of the reaction progress variable conditional upon the reaction progress variable tend to cancel each other in the vicinity of the critical points associated with cylindrical topologies. Thus, the singular contributions in these terms, which are obtained from analytical descriptions in the vicinity of tunnel formation and tunnel closure topologies, do not affect the balance equation of the magnitude of the gradient of the reaction progress variable. Consequently, there is no need for a separate model treatment for singularities in modelling approaches based on the magnitude of the gradient of the reaction progress variable. The FSI events in the reaction dominated and propagating flame regions of MILD combustion have also been analysed for the first time. It has been found that more FSI events occur in the reaction dominated region, particularly towards the burned gas side. However, the majority of spherical FSI topologies are found in the propagating flame region. The findings from this study indicate that turbulence intensity, dilution level and mixture inhomogeneity effects need to be considered in any attempt to extend flame surface-based modelling approaches to MILD combustion. [ABSTRACT FROM AUTHOR]

In order to investigate the influence of primary production, dilution and preservation on organic matter accumulation, geochemical data and geochemical proxies of primary production, clastic influx and redox conditions were presented from the Cambrian Niutitang Formation organic-rich shales. The primary production proxies (TOC, Mo, P, Ba and Babio) and redox proxies (Ni/Co, V/Cr, U/Al and Th/U) suggest that the black organic-rich shales of the Niutitang Formation are deposited in anoxic/euxinic condition with high primary production. The pyrite of the Niutitang Formation is composed of spherical framboids, indicating that the anoxic bottom water could not prevail before organic matter degradation during the Niutitang Formation deposition. High primary production enhances organic carbon flux into chemocline layer and bottom water, leading to the anoxic bottom water from oxygen consumption by microorganisms and organic matter degradation. The anoxic bottom water in turn is beneficial to preservation of organic matter. In addition, Ti/Al ratios correlate well with TOC contents through the Niutitang Formation, indicating that clastic inputs enhance the burial rate for preventing organic matter from degradation during Niutitang Formation deposition. Therefore, the accumulation of organic matter in the Niutitang Formation is mainly influenced by primary production rather than the redox conditions in bottom water. [ABSTRACT FROM AUTHOR]

The generation of gas mixtures of polar organic compounds at the level of their maximum permissible concentrations (several μg/m3) by continuous gas extraction from aqueous solutions with known concentrations in combination with dilution with a diluent gas flow was studied. The distribution coefficients of phenol, isomeric cresols, nitrobenzene, and C4–C6 alkanols between aqueous and gas (nitrogen) phases necessary for this study were determined. A two-stage generation technique based on the saturation of a sorbent (activated carbon) with an extractant gas flow with a given concentration of target components followed by their desorption by a flow of pure extractant gas was proposed. [ABSTRACT FROM AUTHOR]

Context: One of the prevalent methods for evaluating separation performance is to predict the interactions of solvent and solute molecules. The infinite dilution activity coefficient, Gibbs free energy, and sigma profiles provided insights into the solubilization of a solute and revealed the intensity of the solution's molecular interactions. The effective thermodynamic tools (infinite dilution activity coefficient, Gibbs free energy) were evaluated for predicting the efficiency of 18 polar and non-polar organic solvents in rubber seed oil (RSO) extraction. An infinite dilution activity coefficient was computed to evaluate the solubility of the rubber seed oil model compound (linoleic acid) in the organic solvents. Gibbs free energy was evaluated to show the energy change associated with the molecules mixing process and forecast the miscibility of linoleic acid molecules in the solvents. Moreover, the study examined the sigma profiles and sigma surfaces of organic solvents and linoleic acid to acquire a deeper insight into their similarities and how they interact molecularly. According to the computational prediction and experimental verification, the thermodynamic properties of Gibbs free energy and activity coefficient proved to be highly effective tools for screening polar and moderately polar solvents, predicting the molecular interactions with solute. Whereas the sigma profile and sigma surface were found to be the most efficient tools for evaluating the efficacy of non-polar solvents. Solvents with moderate polarity, such as tetrahydrofuran and diethyl ether, as well as non-polar solvents like pentane, heptane, and n-hexane, proved to be effective and favorable for oil extraction, resulting in the highest oil yields of approximately 27.0%. Overall, the COSMO-RS method demonstrates its utility in estimating the solubility of RSO in organic solvents, enabling early identification of the most effective solvent. Methods: The initial geometry optimization of every component was conducted through density functional theory (DFT) using TmoleX software. A single-point density functional theory (DFT) computation using Becke Perdew 86 (BP86) and the Triple-Zeta Valence Potential (TZVPD) was performed to produce.cosmo files. COSMO-RS calculations were performed by applying the parameterization file BP_TZVPD_FINE_19.ctd using COSMOthermX software. The practical extraction of oil from plant seeds was performed using a sonicator bath to verify the accuracy of the COSMO-RS predictions. [ABSTRACT FROM AUTHOR]

Rapid assessment of salinity based on the electrical conductivity of the liquid phase of the soil is widely used throughout the world. However, the results of such an assessment strongly depend on the soil–water relationship, while the known salinity standards based on electrical conductivity are proposed for a soil solution in the state of soil water saturation (full moisture capacity). Thus, a serious underestimation of the degree of salinity may occur when studying water extracts (suspensions) with an obviously higher soil–water ratio compared to the state of full moisture capacity. In this regard, the purpose of the study was to compare the GOST methodology in Russia with a soil–water ratio of 1 : 5 and the classical Richards method with the assessment of the electrical conductivity of the soil solution in a water-saturated state using the example of arid soils of different genesis and dispersion of the Republic of Uzbekistan. In contrast to well-known works on the empirical assessment of the influence of the soil–water relationship on the conductometric assessment of salinity, we applied the fundamental theory of dilution to justify the reduction of the results to a standard state of water saturation and the possibility of using the international classification of soils according to the degree of salinity. The results showed satisfactory agreement between the experimental data and the theory of solution dilution in the range of electrical conductivity values up to 30–35 dS/m, that is, up to a gradation of a very strong degree of salinity according to the international classification. Deviations from the theory can be explained by the nonlinearity of the dependence of electrical conductivity on the concentration of electrolytes and the immobilization of ions by the solid phase and thin pores, as well as a higher yield of electrolytes into solution at high dilution compared to the standard state of water saturation. [ABSTRACT FROM AUTHOR]

Experimental investigations of n-butane oxidation under atmospheric-pressure plasma conditions and in He-dilution have provided detailed information on the power-dependence of the conversion of C 4 H 10 into CO and CO 2 at 450 K surface temperature. The rf-plasma discharge has been equipped with a MnO 2 -catalyst, and a significant impact on the reaction chain due to the presence of the catalyst surface could be observed. We report on ongoing data-based model development. Recently, a reaction kinetic model has been published, which agrees well with the experimental data (Stewig et al. in Plasma Sources Sci Technol 32:105006, 2023). However, that model could not clearly identify the main mechanisms in the interaction of plasma and catalyst. We show that various models can be found that explain the data similarly well. Detailed sensitivity analysis shows that only a maximum of three parameters can be identified in all the models considered for the currently limited data. Despite this limitation, we intend to continue the data analysis using more general models and introduce possible surface effects. Such unified models simultaneously describe the experimental data from both measurements with and without catalyst using a single set of physical parameters. To evaluate the hypotheses, we present numerical results for certain ranges of experimental parameters, which, in a subsequent experimental verification, allows to exclude or confirm one or another model. [ABSTRACT FROM AUTHOR]

5-Fluorouracil is a chemotherapeutic agent used for the treatment of different kinds of cancers and Amlodipine Besylate is a vasodilator used to cure hypertension and angina. In order to improve different properties of drugs like drug solubility, mask bitter taste, prevent photodegradation, and for controlled drug delivery, the host–guest, solid inclusion complexes of 5-flurouracil (5-FU) and Amlodipine Besylate (ABS) with beta-cyclodextrin (β-CD) were utilized for different studies in this manuscript which were prepared through traditional methods and microwave-prompted technique. Different parameters such as apparent molar volume (Vϕ), partial molar volume at infinite dilution (Vϕ0), apparent molar isentropic compression (Kϕ,s), partial molar isentropic compression at infinite dilution (K0ϕ,s) were obtained from experimental density and speed of sound data. The partial molar volume at infinite dilution (Vϕ0 × 106/m3 mol−1) values of β-CD in aqueous solution of drug ABS was found 79.83, 80.32 and 80.64 at 305.15, 310.15 and 315.15 K, respectively. The partial molar volume at infinite dilution (Vϕ0 × 106/m3 mol−1) values of β-CD in aqueous solution of drug 5-FU was found − 252.61, − 246.42 and − 255.74 at 305.15, 310.15 and 315.15 K, respectively. The value of solubility constant (Ks) was found to be 74.3822 ± 4 M−1 for 5-FU and 204.0811 ± 4.75 M−1 for ABS in phase solubility studies. The inclusion complexes (ICs) were incorporated into the hybrid polymer networks (HPNs) of chitosan and gelatin to explore drug release studies. A comparison of directly loaded drug into the HPNs was made with the cyclodextrin-mediated release. The ICs prepared by different methods were also compared for the drug release. [ABSTRACT FROM AUTHOR]

Biological assays around "lab-on-a-chip (LoC)" are required in multiple concentration (or dilution) factors, satisfying specific sample concentrations. Unfortunately, most of them suffer from non-locality and are non-protectable, requiring a large footprint and high purchase cost. A digital geometric technique can generate arbitrary gradient profiles for digital microfluidic biochips (DMFBs). A next- generation DMFB has been proposed based on the microelectrode-dot-array (MEDA) architectures are shown to produce and disperse droplets by channel dispensing and lamination mixing. Prior work in this area must address the problem of reactant and waste minimization and concurrent sample preparation for multiple target concentrations. This paper proposes the first splitting-droplet sharing algorithm for reactant and waste minimization of multiple target concentrations on MEDAs. The proposed algorithm not only minimizes the consumption of reagents but also reduces the number of waste droplets by preparing the target concentrations concurrently. Experimental results on a sequence of exponential gradients are presented in support of the proposed method and demonstrate its effectiveness and efficiency. Compared to prior work, the proposed algorithm can achieve up to a 24.8% reduction in sample usage and reach an average of 50% reduction in waste droplets. [ABSTRACT FROM AUTHOR]

We analytically investigate the zero-temperature hysteresis loops in a one-dimensional 3-state clock model in the low disorder limit, incorporating dilution and quenched spins. Utilizing a probabilistic approach with continuous random fields, we study the behavior of the model at nearly zero frequency limit of the applied field and confirming our analytical results via simulations. Dilution reproduces distorted hysteresis loop shapes akin to those in geological magnetic rocks, while quenched spins significantly contribute to hysteresis loop asymmetry. [ABSTRACT FROM AUTHOR]

In the flux cored arc welding of high-Mn steels, the effects of the welding position and heat input on the dilution rate and mechanical properties were investigated using an austenitic stainless steel filler with a lower strength than that of the base metal. Horizontal (2G) and vertical-up (3G-UP) position welding was conducted under low- and high-heat input conditions. The 3G-UP welding position had a higher dilution rate than the 2G welding position, and the yield strength and tensile strength were relatively high at appropriate heat input rather than excessive heat input in 3G-UP. A fully austenitic microstructure with a dendritic structure was primarily observed, and oxide inclusions were observed in the weld metal. The primary dendrite arm spacing was dependent on the heat input rather than on the chemical composition. From the multiple regression model based on the chemical composition and heat input, the strength of the weld metal was determined mainly by monitoring the welding heat input and C, Cu, Mo, and Cr contents. The soundness of high-Mn steel welds with an under-matched filler was confirmed to fulfill the mechanical property requirements for cryogenic applications regardless of the welding position and heat input, and an empirical model to estimate the strength of high-Mn welds was established as follows: Yield Strength (MPa) = 297.7 + 382 × C + 23.2 × Mo + 2.93 × Cr + 438 × Cu – 2.58 × Heat Input (HI). [ABSTRACT FROM AUTHOR]

Heat shock protein 90α (HSP90α) has been regarded as an important indicator for judging tumor metastasis and prognosis due to its significant upregulation in various tumors. Therefore, the accurate quantification of HSP90α is of great significance for clinical diagnosis and therapy of cancers. However, the lack of HSP90α certified reference material (CRM) leads to the accuracy and consistency of quantification methods not being effectively evaluated. Besides, quantitative results without traceability make comparisons between different studies difficult. In this study, an HSP90α solution CRM was developed from the recombinant protein raw material. The recombinant protein is a dimer, and the purity of the CRM candidate reached 96.71%. Both amino acid analysis-isotope dilution mass spectrometry (AAA-IDMS) and unique peptide analysis-isotope dilution mass spectrometry (UPA-IDMS) were performed to measure the content of HSP90α in the solution CRM candidate, and the certified value was assessed to be 66.2 ± 8.8 µg/g. Good homogeneity of the CRM was identified, and the stability examination suggested that the CRM was stable for at least 4 months at − 80 °C and for 7 days at 4 °C. With traceability to SI unit (kg), this CRM has potential to help establish a metrological traceability chain for quantification of HSP90α, which will make the quantification results standardized and comparable regardless of the quantitative methods. [ABSTRACT FROM AUTHOR]

To guide the development of CaO–Al2O3-based non-reactive mold flux for low-density high-strength steel production, CaO–Al2O3–CaF2 slags were calculated by first-principles molecular dynamics. The results showed that the stability order of corresponding bonds was Al–O > Ca–F > Ca–O > Al–F. With F− addition, the stability of Al–O and Al–F bonds enhanced, and that of Ca–O bond decreased while Ca–F bond almost did not change. Furthermore, although lower CaO/Al2O3 ratio increased the structure complex, the depolymerization and dilution of F played a dominant role to reduce the viscosity. Al–O and Al–F were charge-transfer bond, while Ca–O and Ca–F were ionic bond. The unstable hexahedron AlO4F evolved into tetrahedral AlO3F and AlO4 dynamically. In addition, the low content of F mainly formed AlO3F structure to depolymerize and stabilize the Al–O network structure, while the high content of F promoted AlO4F structure to reduce the symmetry and stability of slag. [ABSTRACT FROM AUTHOR]

A freeze-dried bovine muscle–certified reference material (CRM), known as BOTS-1 (DOI: https://doi.org/10.4224/crm.2018.bots-1), containing incurred residues of commonly used veterinary drugs was produced and certified for the mass fraction of eight veterinary drug residues. Value assignment was carried out using liquid chromatography tandem mass spectrometry (LC–MS/MS) methods in conjunction with isotope dilution and standard addition approaches involving stable isotope internal standards. Data from the National Research Council of Canada (NRC), Canadian Food Inspection Agency (CFIA), United States Department of Agriculture (USDA), and the Federal Office of Consumer Protection and Food Safety in Germany (BVL) were used for value assignment. Results for two drug residues were also obtained through an international inter-laboratory comparison CCQM-K141/P178 organized under the auspices of the International Bureau of Weights and Measures (BIPM). Quantitative NMR (1H-qNMR) was used to characterize primary standards of all veterinary drugs certified. The certified mass fractions of the veterinary drug residues were 490 ± 100 µg/kg for chlorpromazine, 44 ± 4.4 µg/kg for ciprofloxacin, 3.3 ± 1.4 µg/kg for clenbuterol, 9.5 ± 0.8 µg/kg for dexamethasone, 57 ± 4.8 µg/kg for enrofloxacin, 3.0 ± 0.4 µg/kg for meloxicam, 12.4 ± 1.2 µg/kg for ractopamine, and 2290 ± 120 µg/kg for sulfadiazine with expanded uncertainties quoted (95% confidence) which include the effects due to between-bottle inhomogeneity, instability during long-term storage and transportation, and characterization. [ABSTRACT FROM AUTHOR]

To enhance the combustion efficiency and reduce NOx emissions in large-scale semicoke and bituminous coal blends, an extensive numerical study was conducted. The focus of this study was to optimize the quaternary air vane angle (αv) through detailed analysis of the temperature and flow fields, turbulence–chemistry interactions, char burnout, and NOx formation in a carefully scaled 1:5 dual-swirl burner. The results showed that with increasing αv, the high-temperature flame region was narrowed and the peak temperature was reduced along with the broadened inner recirculation zone and the shrunken external recirculation zone due to better pulverized fuel-oxidant blending and reinforced convective heat transfer. The peak turbulent Damköhler number Dat evidently increased from 197.5 to 496 with increasing αv, which implied a strengthened homogeneous combustion. Additionally, the corresponding mixing time scales increased while the chemical kinetics time scales decreased, which denoted that an intense diffusing flame was generated with a strong turbulent intensity. The peak heterogeneous Damköhler number Das-O2 showed a reduction from 2.54 to 2.27, while the peak values of Das-CO2 and Das-H2O decreased from 0.1 to 0.077 and from 0.02 to 0.015, respectively. The char–O2 reaction was controlled by diffusion/kinetics; both char–CO2 and char–H2O reactions were determined by kinetics, and all gas‒solid reactions showed a kinetically controlled regime. With increasing αv, the enlarged inner recirculation region increased the residence time, and a higher dilution level lessened the peak temperature, which led to reductions in fuel-NOx and the thermal-NOx. The αv range of 30–45° (or swirl number Sn = 0.55–0.95) was suggested by taking the high burnout and low-NOx formation into account. [ABSTRACT FROM AUTHOR]

Nest survival may be affected in several ways by predator-mediated interactions. According to the "predator dilution effect hypothesis", the daily nest survival rate (DSR) can be density-dependent, because the probability of nest predation decreases as the number of active nests increases. Additionally, parental activity may increase with clutch size, nest age, and after low-temperature periods, while climatic components such as air humidity and moderate winds can increase odour dissipation from nests. Consequently, predators can use these cues to locate nests, reducing the DSR. Determining such predator-mediated interactions is important to understand how multiple causes can affect avian reproductive success. Thus, we evaluated the effects of predation and predator-mediated interactions of abundance of active nests, parental investment and climate on annual and seasonal variations in DSR of the Chilean Elaenia (Elaenia chilensis), a long-distance migratory passerine that breeds in the Andean-Patagonian Forest. We monitored nests over four breeding seasons and modelled DSR for 86 nests. The mean ± SE DSR was 0.960 ± 0.005, corresponding to an overall nest success of 29.5%. DSR increased with the abundance of active nests, but it did not vary among years or throughout the breeding season, nor was it affected by other variables. Hence, there was no influence of parental investment and climate on predation. Instead, the increase in abundance of active nests towards the middle of the breeding season reduces the probability of predation per nest, resulting in greater Chilean Elaenia nest survival, and providing empirical support for the "predator dilution effect hypothesis". [ABSTRACT FROM AUTHOR]

The solubility of propane (C3H8, component 2) in pure liquid water (H2O, component 1) was determined at a total pressure of about 100 kPa from about T = 278 K to T = 318 K using an analytical method characterized by an imprecision of about ± 0.1% or less. The measurements were made with a Benson-Krause-type apparatus at roughly 5 K intervals. From the experimental results, Henry's law constants h 2 , 1 T , P σ , 1 , also known as Henry fugacities, at the vapor pressure P σ , 1 T of water, as well as the Ostwald coefficient L 2 , 1 ∞ T , P σ , 1 at infinite dilution are rigorously obtained. The temperature dependence is accounted for by a three-constant Benson-Krause equation, i.e., by fitting ln h 2 , 1 T , P σ , 1 / kPa to a power series in 1/T. Subsequently, the partial molar enthalpy changes on solution Δ H 2 ∞ of propane in water, and the partial molar heat capacity changes on solution Δ C P , 2 ∞ , are reported (van 't Hoff analysis) and compared with calorimetrically determined quantities: agreement is highly satisfactory. We believe that our new values for the Henry fugacity and the Ostwald coefficient of propane dissolved in liquid water are the most reliable ones to date. [ABSTRACT FROM AUTHOR]

Productivity benefits from diversity can arise when compatible pathogen hosts are buffered by unrelated neighbors, diluting pathogen impacts. However, the generality of pathogen dilution has been controversial and rarely tested within biodiversity manipulations. Here, we test whether soil pathogen dilution generates diversity- productivity relationships using a field biodiversity-manipulation experiment, greenhouse assays, and feedback modeling. We find that the accumulation of specialist pathogens in monocultures decreases host plant yields and that pathogen dilution predicts plant productivity gains derived from diversity. Pathogen specialization predicts the strength of the negative feedback between plant species in greenhouse assays. These feedbacks significantly predict the overyielding measured in the field the following year. This relationship strengthens when accounting for the expected dilution of pathogens in mixtures. Using a feedback model, we corroborate that pathogen dilution drives overyielding. Combined empirical and theoretical evidence indicate that specialist pathogen dilution generates overyielding and suggests that the risk of losing productivity benefits from diversity may be highest where environmental change decouples plant-microbe interactions. Soil pathogen dilution can improve plant production. Here, the authors combine an empirical and theoretical approaches finding that specialist pathogens suppress yield in monocultures while pathogen dilution drives yield benefits in diverse plant communities. [ABSTRACT FROM AUTHOR]

The anomalous viscosity of colloidal dispersions of silica has been known and studied for a long time. Several different mechanisms have been proposed to explain it, related to the electrical double layer, hydration layer, and porous/gel layer at the silica-water interface. However, it is still not entirely clear which mechanism is actually operative. Here, based on measurements of viscosity dependence on the concentration of indifferent electrolyte in highly diluted colloidal silica systems and its interpretation using the well-known Einstein equation, the concept of a swellable polyelectrolyte gel layer is corroborated. [ABSTRACT FROM AUTHOR]

l-Aspartic acid (ASP) and l-glutamic acid (GLU) in aqueous solution of a food additive, sodium acetate (SA) have been taken for acoustic and conductometric studies. The experimental results are analysed to predict and assess the solvation behaviour and types of interactions occurring in these ternary solutions [ASP/GLU + SA + water]. Compressibility parameters like isentropic compressibility and apparent molar isentropic compressibility along with their values at infinite dilution have been computed. Transfer values and ion pair and triplet interactions have been determined. Other thermodynamic parameters like internal pressure, molar free volume, relative association and acoustic impedance, have also been derived from the acoustic data. Specific conductance values measured experimentally led to the calculation of molar conduction of electric charge. Walden product sheds light on structure building or breaking properties of the amino acids. Gibbs thermodynamic functions predict the spontaneity of ion association process. Arrhenius equation is used to calculate activation energy which is indicative of the formation of high-energy transition state required for migration of ions. Analysis of these results establishes the amino acids as water-structure forming agents and predominance of ion–solvent, ion–ion and ion–hydrophilic interactions in the studied systems. [ABSTRACT FROM AUTHOR]

To solve the problem of flammability of cotton fabrics and enhance their application in areas with high fire resistance requirements, we have developed a hybrid coating (TSNP) containing phosphorus, nitrogen, and silicon elements, which can simultaneously impart excellent hydrophobicity and flame retardancy to cotton fabrics. Cotton modified with TSNP can achieve the effect of immediately extinguishing the flame by removing the igniter in vertical combustion experiments, while also have an oxygen index of 26.5%. Cone calorimeter tests show flame-retardant cottons have a lower total heat release and peak of heat release rate compared to pure cotton. In addition, TSNP coating also enhances the hydrophobicity of the cotton fabric, with a hydrophobicity angle of 123.5°. The research on gas phase pyrolysis process from TG-IR reveals that TSNP can exert capture effect on active free radicals and the dilution effect on combustible gases. Meanwhile, the study on the chars after burning from XPS, SEM and IR shows TSNP also can form a dense carbon layer, thereby exerting a barrier effect on heat and combustible gases. [ABSTRACT FROM AUTHOR]

Nova-C is a lunar lander developed by the private company Intuitive Machines to deliver commercial payloads to the Moon. The IM-1 mission will launch and land the Nova-C near the Moon's south pole. In this paper, Batch Dilution of Precision (DOP) methods are explored to assess Orbit Determination (OD) performance based on the nominal IM-1 trajectory. Utilizing a range to range-rate measurement error ratio to normalize the position uncertainties, this paper lays out the methodology to derive and incorporate a recursive, time-series Batch Least-Squares algorithm. Through the normalization, the Batch Least Squares algorithm produces a unitless Position Dilution of Precision metric. The normalized-weighted DOP method is used within a genetic algorithm optimizer to determine ground station tracking schedules that optimize OD performance. An assessment of OD performance is studied for key mission events including trajectory correction maneuvers, lunar orbit insertion, and descent orbit insertion. The long-term goal of this research is to develop a fully integrated DOP and Linear Covariance Analysis optimization tool to minimize operational costs and maximize OD performance. [ABSTRACT FROM AUTHOR]

The Dorfman pooled testing scheme is a process in which individual specimens (e.g., blood, urine, swabs, etc.) are pooled and tested together; if the merged sample tests positive for infection, then each specimen from the pool is tested individually. Through this procedure, laboratories can reduce the expected number of tests required to screen the population, as individual tests are only carried out when the pooled test detects an infection. Several different partitions of the population can be used to form the pools. In this study, we analyze the performance of ordered partitions, those in which subjects with similar probability of infection are pooled together. We derive sufficient conditions under which ordered partitions outperform other types of partitions in terms of minimizing the expected number of tests, the expected number of false negatives, and the expected number of false positive classifications. These sufficient conditions can be easily verified in practical applications once the dilution effect has been estimated. We also propose a measure of equity and present conditions under which this measure is maximized by ordered partitions. [ABSTRACT FROM AUTHOR]

In the ongoing global fight against coronavirus disease 2019 (COVID-19), the sample preparation process for real-time reverse transcription polymerase chain reaction (rRT-PCR) faces challenges due to time-consuming steps, labor-intensive procedures, contamination risks, resource demands, and environmental implications. However, optimized strategies for sample preparation have been poorly investigated, and the combination of RNase inhibitors and Proteinase K has been rarely considered. Hence, we investigated combinations of several extraction-free protocols incorporating heat treatment, sample dilution, and Proteinase K and RNase inhibitors, and validated the effectiveness using 120 SARS-CoV-2 positive and 62 negative clinical samples. Combining sample dilution and heat treatment with Proteinase K and RNase inhibitors addition exhibited the highest sensitivity (84.26%) with a mean increase in cycle threshold (Ct) value of + 3.8. Meanwhile, combined sample dilution and heat treatment exhibited a sensitivity of 79.63%, accounting for a 38% increase compared to heat treatment alone. Our findings highlight that the incorporation of Proteinase K and RNase inhibitors with sample dilution and heat treatment contributed only marginally to the improvement without yielding statistically significant differences. Sample dilution significantly impacts SARS-CoV-2 detection, and sample conditions play a crucial role in the efficiency of extraction-free methods. Our findings may provide insights for streamlining diagnostic testing, enhancing its accessibility, cost-effectiveness, and sustainability. [ABSTRACT FROM AUTHOR]

The need for developing metrological support for the measurement of gas components in metals and alloys and trace impurities in various industrial products (metallurgy, medicine, etc.) is analyzed. The authors examine the needs of industries for the development of more sensitive measurement methods and procedures, as well as an expanded nomenclature of reference materials having a lower error (uncertainty) of the certified characteristic than the certified characteristic error of currently existing type-approved composition reference materials. Reference materials developed for use in state regulation should be traceable to the primary standards of mass (molar) fraction and mass (molar) concentration: GET 196-2023 State Primary Standard for the units of the mass (molar) fraction and mass (molar) concentration of components in liquid and solid substances and materials based on spectral methods; GET 176-2019 State Primary Standard for the units of mass (molar, atomic) fraction and mass (molar) concentration of components in liquid and solid substances and materials based on coulometry; GET 217-2018 State Primary Standard for the units of mass fraction and mass (molar) concentration of inorganic components in aqueous solutions based on gravimetric and spectral methods; GET 208-2019 State Primary Standard for the units of mass (molar) fraction and mass (molar) concentration of organic components in liquid and solid substances and materials based on liquid and gas chromatography-mass spectrometry with isotope dilution and gravimetry. The need for and ways of developing and creating a metrological support system for Raman spectrometry in the Russian Federation are analyzed, including to confirm the traceability of units for quantitative Raman analysis. To address these issues, GET 196-2023 includes sulfur, carbon, and hydrogen analyzers; an inductively coupled plasma mass spectrometer; and a Raman system. The composition and metrological characteristics of GET 196-2023 are presented. In addition, a draft state hierarchy scheme for instruments measuring mass (molar) fraction and mass (molar) concentration, as well as fluorescence, of components in liquid and solid substances and materials based on spectral methods has been developed and presented. The draft state verification scheme establishes the procedure and methods for transferring the units of the mass (molar) fraction (in absolute units) and mass (molar) concentration of components (grams per cubic decimeter; mole per cubic decimeter) from GET 196-2023 to measuring instruments with indication of measurement error and uncertainty. Also, secondary and working standards are used to transfer relative fluorescence units to measuring instruments. [ABSTRACT FROM AUTHOR]

Huangqi Guizhi Wuwu decoction (HGWD), as a classical formula, has been used for thousands of years in China. In this work, a comprehensive strategy was proposed for characterizing the chemical profile of HGWD based on online two-dimensional hydrophilic interaction and reversed-phase liquid chromatography coupled with hybrid linear ion trap-Orbitrap mass spectrometry (online HILIC × RP-ESI/HRMS/MSn). The compounds in HGWD were first separated by the combined use of an XBridge amide column (150 × 4.6 mm, 3.5 μm) and Accucore C18 column (50 mm × 4.6 mm, 2.6 μm). Modulation with assistant technology, including trap columns and online dilution, was optimized and developed to decrease potential analyte loss and improve the resolution of the system. Subsequently, the accurate mass was determined by high-resolution Orbitrap and MSn fragment data by a hybrid linear ion trap (LTQ). In total, 170 chemical constituents were unambiguously identified or tentatively characterized in both positive and negative ion modes. Our study demonstrated that the proposed online HILIC × RP system coupled to the LTQ-Orbitrap MS platform is an efficient analytical technique for characterizing the chemical profile of multicomponent systems. [ABSTRACT FROM AUTHOR]

The growth kinetics of 4He crystals nucleated in a metastable liquid at a supersaturation of up to 10mbar is studied in the temperature range 90–180 mK. An optical dilution cryostat is used to observe and film crystal growth. The boundary supersaturation separating the normal (slow) and abnormal (fast) growth regions is determined. The growth rate of crystal facets in the normal growth mode is measured. The kinetics of fast crystal growth is investigated as a function of supersaturation and temperature. [ABSTRACT FROM AUTHOR]