Deconstructing 3D growth rates from transmission microscopy images of facetted crystals as captured in situ within supersaturated aqueous solutions.

Here, a morphologically based approach is used for the in situ characterization of 3D growth rates of facetted crystals from the solution phase. Crystal images of single crystals of the ß-form of l-glutamic acid are captured in situ during their growth at a relative supersaturation of 1.05 using transmission optical microscopy. The crystal growth rates estimated for both the {101} capping and {021} prismatic faces through image processing are consistent with those determined using reflection light mode [Jiang, Ma, Hazlehurst, Ilett, Jackson, Hogg & Roberts (2024 ▸). Cryst. Growth Des. 24, 3277-3288]. The growth rate in the {010} face is, for the first time, estimated from the shadow widths of the {021} prismatic faces and found to be typically about half that of the {021} prismatic faces. Analysis of the 3D shape during growth reveals that the initial needle-like crystal morphology develops during the growth process to become more tabular, associated with the Zingg factor evolving from 2.9 to 1.7 (>1). The change in relative solution supersaturation during the growth process is estimated from calculations of the crystal volume, offering an alternative approach to determine this dynamically from visual observations.

Time-resolved observation of DHR123 nano-clay radio-fluorogenic gel dosimeters by photoluminescence-detected pulse radiolysis.

The importance of real-time dose evaluation has increased for recent advanced radiotherapy. However, conventional methods for real-time dosimetry using gel dosimeters face challenges owing to the delayed dose response caused by the slow completion of radiation-induced chemical reactions. In this study, a novel technique called photoluminescence-detected pulse radiolysis (PLPR) was developed, and its potential to allow real-time dose measurements using nano-clay radio-fluorogenic gel (NC-RFG) dosimeters was investigated. PLPR is a time-resolved observation method, and enables time-resolved fluorescence measurement. NC-RFG dosimeters were prepared, typically consisting of 100 µM dihydrorhodamine 123 (DHR123) and 2.0 wt.% nano-clay, along with catalytic and dissolving additives. We successfully achieved time-resolved observation of the increase in fluorescence intensity upon irradiation of the dosimeter. Dose evaluation was possible at 1 s after irradiation. The dose-rate effect was not observed for the deoxygenated dosimeter, but was observed for the aerated dosimeter. Besides the dose-rate effect, linear dose responses were obtained for both conditions. Furthermore, we made a novel observation of a decay in the fluorescence intensity over time in the early stages which named fluorescence secondary loss (FSL) and elucidated the conditions under which this phenomenon occurs.

TENSOR REGRESSION FOR INCOMPLETE OBSERVATIONS WITH APPLICATION TO LONGITUDINAL STUDIES.

Multivariate longitudinal data are frequently encountered in practice such as in our motivating longitudinal microbiome study. It is of general interest to associate such high-dimensional, longitudinal measures with some univariate continuous outcome. However, incomplete observations are common in a regular study design, as not all samples are measured at every time point, giving rise to the so-called blockwise missing values. Such missing structure imposes significant challenges for association analysis and defies many existing methods that require complete samples. In this paper we propose to represent multivariate longitudinal data as a three-way tensor array (i.e., sample-by-feature-by-time) and exploit a parsimonious scalar-on-tensor regression model for association analysis. We develop a regularized covariance-based estimation procedure that effectively leverages all available observations without imputation. The method achieves variable selection and smooth estimation of time-varying effects. The application to the motivating microbiome study reveals interesting links between the preterm infant's gut microbiome dynamics and their neurodevelopment. Additional numerical studies on synthetic data and a longitudinal aging study further demonstrate the efficacy of the proposed method.

Accurate locomotor activity profiles of group-housed mice derived from home cage monitoring data.

Introduction: Holistic phenotyping of rodent models is increasing, with a growing awareness of the 3Rs and the fact that specialized experimental setups can also impose artificial restrictions. Activity is an important parameter for almost all basic and applied research areas involving laboratory animals. Locomotor activity, the main form of energy expenditure, influences metabolic rate, muscle mass, and body weight and is frequently investigated in metabolic disease research. Additionally, it serves as an indicator of animal welfare in therapeutic, pharmacological, and toxicological studies. Thus, accurate and effective measurement of activity is crucial. However, conventional monitoring systems often alter the housing environment and require handling, which can introduce artificial interference and lead to measurement inaccuracies. Methods: Our study focused on evaluating circadian activity profiles derived from the DVC and comparing them with conventional activity measurements to validate them statistically and assess their reproducibility. We utilized data from metabolic studies, an Alzheimer's disease model known for increased activity, and included DVC monitoring in a project investigating treatment effects on activity in a type-1-like diabetes model. Results: The DVC data yielded robust, scientifically accurate, and consistent circadian profiles from group-housed mice, which is particularly advantageous for longitudinal experiments. The activity profiles from both systems were fully comparable, providing matching profiles. Using DVC monitoring, we confirmed the hyperactivity phenotype in an AD model and reproduced a decline in activity in type-1-like diabetes model. Discussion: In our work, we derived robust circadian activity profiles from the DVC data of group-housed mice, which were scientifically accurate, reproducible and comparable to another activity measurement. This approach can not only improve animal welfare according to the 3R principles but can also be implement in high-throughput longitudinal studies. Furthermore, we discuss the advantages and limitations of DVC activity measurements to highlight its potential and avoid confounders.

Patterns and determinants of micronutrient dietary biomarkers and their associations with dietary intakes in young children.

BACKGROUND: Circulating dietary biomarkers are not direct proxies for intake, as the biomarkers reflect not only food and supplement consumption but also nutrient absorption, metabolism, and tissue distribution. Therefore, along with nutrient intake, several other upstream factors can impact dietary biomarker concentrations, including demographic, medical history, and genetic factors. OBJECTIVE: The aim of this study was to explore the dietary and nondietary determinants of circulating levels of vitamins A, C, D, and E among children aged 6 months to 4 years. METHODS: Plasma retinol, beta-carotene, ascorbic acid, 25(OH)D, alpha-tocopherol, and gamma-tocopherol were measured in 2887 samples from 1490 children enrolled in The Environmental Determinants of Diabetes in the Young (TEDDY) study. Dietary intake was assessed with 3-day food records. Associations of genetic and environmental factors with biomarker concentrations were examined using multivariable linear regression models with random intercepts. RESULTS: All biomarkers except retinol were positively associated with intake of the same nutrient. Inverse associations were identified between recent gastrointestinal infection and ß-carotene, ascorbic acid, and α-tocopherol, while recent respiratory infection was associated inversely with plasma retinol. Several genetic determinants of biomarker status were identified, validating previously reported findings. For some genetic and environmental exposures, we found evidence of statistical interaction with same-nutrient intake, indicating that the association between intake and biomarker concentration is dependent upon the level or status of these other exposures. For example, the association between ß-carotene intake and concentration is weaker among children with a recent respiratory infection. CONCLUSIONS: Our findings suggest that non-dietary exposures including childhood infections can alter micronutrient metabolism. This summary of micronutrient determinants will facilitate improved design of future analyses exploring the role of diet in childhood chronic disease etiology through a better understanding of relevant potential confounders and mediators of the diet-outcome relationships.

Significance of resected stomach measurements in postoperative delayed gastric emptying following laparoscopic pylorus-preserving gastrectomy.

PURPOSE: We investigated the relationship between the resected stomach measurements, the incidence of delayed gastric emptying (DGE), and food residue 1 year after surgery in patients who underwent laparoscopic pylorus-preserving gastrectomy (PPG). MATERIALS AND METHODS: The DGE group included 10 patients fasting due to nausea, vomiting, abdominal distension, or remnant stomach distension on radiographs; the control group included 36 patients without these symptoms. We compared the size and length of lesser and greater curvatures of the resected stomach and endoscopic findings after 1 year. RESULTS: No significant differences were observed between groups in terms of sex, body mass index, gross type, histology, tumor progression, number of dissected lymph nodes, operating time, or blood loss. The DGE group was older, had a longer postoperative stay, and showed a smaller size and shorter greater curvature of the resected stomach than the control group (p < 0.01 for all). No difference was observed in the length of the lesser curvature of the resected stomach. In addition, there were no disparities in residual food, degree and extent of gastritis, or bile reflux 1 year after gastrectomy. CONCLUSIONS: Measurements of the resected stomach suggest that preventing DGE may be achievable by removing a larger area of the greater curvature and/or stomach during laparoscopic PPG. This implies potential surgical strategy improvements for better outcomes. Further multicenter trials are needed to validate and refine techniques.

Development of a Topological-Insulator-Based Quantum Resistance Standard.

This paper describes the characterization of the quantum anomalous Hall (QAH) effect resistor with Chromium-doped Bismuth Antimony Telluride with the efforts in coupling directly to a programmable Josephson voltage standard (PJVS) at zero magnetic field. The precision measurement of the QAH resistance was performed under the presence of microwave signal biased to the PJVS. Understanding such effect will help to improve the experimental set-up for integrating multiple quantum electrical standards in a single system.

Influences of Variability in Attenuation Compensation on the Estimation of Backscatter Coefficient of Median Nerves in Vivo.

OBJECTIVE: Peripheral nerves remain a challenging target for medical imaging, given their size, anatomical complexity, and structural heterogeneity. Quantitative ultrasound (QUS) applies a set of techniques to estimate tissue acoustic parameters independent of the imaging platform. Many useful medical and laboratory applications for QUS have been reported, but challenges remain for deployment in vivo, especially for heterogeneous tissues. Several phenomena introduce variability in attenuation estimates, which may influence the estimation of other QUS parameters. For example, estimating the backscatter coefficient (BSC) requires compensation for the attenuation of overlying tissues between the transducer and the underlying tissue of interest. The purpose of this study is to extend prior studies by investigating the efficacy of several analytical methods of estimating attenuation compensation on QUS outcomes in the human median nerve. METHODS: Median nerves were imaged at the volar wrist in vivo and beam-formed radiofrequency (RF) data were acquired. Six analytical approaches for attenuation compensation were compared: 1-2) attenuation estimated by applying spectral difference method (SDM) and spectral log difference method (SLDM) independently to regions of interest (ROIs) overlying the nerve and to the nerve ROI itself; 3-4) attenuation estimation by applying SDM and SLDM to ROIs overlying the nerve, and transferring these properties to the nerve ROI; and 5-6) methods that apply previously published values of tissue attenuation to the measured thickness of each overlying tissue. Mean between-subject estimates of BSC-related outcomes as well as within-subject variability of these outcomes were compared among the 6 methods. RESULTS: Compensating for attenuation using SLDM and values from the literature reduced variability in BSC-based outcomes, compared to SDM. Variability in attenuation coefficients contributes substantially to variability in backscatter measurements. CONCLUSION: This work has implications for the application of QUS to in vivo diagnostic assessments in peripheral nerves and possibly other heterogeneous tissues.

From Molecular Electronics to Molecular Intelligence.

Molecular electronics is a field that explores the ultimate limits of electronic device dimensions by using individual molecules as operable electronic devices. Over the past five decades since the proposal of a molecular rectifier by Aviram and Ratner in 1974 ( Chem. Phys. Lett.1974,29, 277-283), researchers have developed various fabrication and characterization techniques to explore the electrical properties of molecules. With the push of electrical characterizations and data analysis methodologies, the reproducibility issues of the single-molecule conductance measurement have been chiefly resolved, and the origins of conductance variation among different devices have been investigated. Numerous prototypical molecular electronic devices with external physical and chemical stimuli have been demonstrated based on the advances of instrumental and methodological developments. These devices enable functions such as switching, logic computing, and synaptic-like computing. However, as the goal of molecular electronics, how can molecular-based intelligence be achieved through single-molecule electronic devices? At the fiftieth anniversary of molecular electronics, we try to answer this question by summarizing recent progress and providing an outlook on single-molecule electronics. First, we review the fabrication methodologies for molecular junctions, which provide the foundation of molecular electronics. Second, the preliminary efforts of molecular logic devices toward integration circuits are discussed for future potential intelligent applications. Third, some molecular devices with sensing applications through physical and chemical stimuli are introduced, demonstrating phenomena at a single-molecule scale beyond conventional macroscopic devices. From this perspective, we summarize the current challenges and outlook prospects by describing the concepts of "AI for single-molecule electronics" and "single-molecule electronics for AI".

Shear rate induced viscosity change of human blood samples and blood mimicking fluids.

Purpose: The aim of this study was to measure blood and blood mimicking fluids viscosity at different shear rates (on the interval of 0.1-5000 1/s and 0.1-10000 1/s) while taking into consideration the measuring device's capability and blood's characteristics. We also provided the measurement results of the most accurate measuring program. Methods: We measured blood samples from five donors, and four different blood mimicking fluid compositions. The measurements were done on an Anton Paar Physica MCR301 rotational rheometer with two measuring programs varying in the shear rate intervals, the number of measuring points and the measuring point durations. Results: The results confirmed the significant shear thinning and thixotropic effects of blood. Blood mimicking fluids also had these characteristics. The measured blood viscosity values are in agreement with those of the literature. Conclusions: It can be concluded that the step test program was able to give more stable results as the measured torque was over the nominal limit of 0.05 ìNm over 0.1 1/s and over the selected torque limit of 0.5 ìNm over 31.6 1/s. Blood mimicking fluid measurement results were different from that of the literature due to different measuring conditions. The sample consisting of water, glycerol and starch mimicked well blood's behaviour and viscosity values at 37 degrees Celsius.

A comparative study of anti-ADAMTS-13 antibody dynamics in immune-mediated thrombotic thrombocytopenic purpura.

Background: Thrombotic thrombocytopenic purpura, particularly its immune-mediated variant (iTTP), necessitates accurate diagnostic approaches for effective management. Objectives: To compare a chemiluminescence immunoassay (CLIA) and an enzyme-linked immunosorbent assay (ELISA) for testing ADAMTS-13 activity and detecting anti-ADAMTS-13 autoantibodies (AAbs) in patients with iTTP. Methods: This study involved 31 paired samples from 12 iTTP patients. ADAMTS-13 activity was measured using the HemosIL AcuStar (Instrumentation Laboratory, CLIA) and Technozym (Technoclone) activity assay (ELISA). The presence of AAbs was assessed using Technozym ADAMTS-13-INH assay (ELISA) and HemosIL AcuStar activity (CLIA) within a Bethesda assay following mixing with normal pool plasma. von Willebrand factor (VWF) multimers were analyzed using the HYDRASYS-2 SCAN system and the HYDRAGEL 5- or 11-VW Multimer kits (Sebia). VWF activity levels were measured with the HemosIL AcuStar VWF:GPIbR on the ACL AcuStar Analyzer (IL). Results: For ADAMTS-13 activity, a strong linear relationship and no bias between CLIA and ELISA were confirmed (slope = 1.01 [0.91, 1.11], intercept = 0.00 [-0.47, 0]). However, significant discrepancies were found in AAb detection during remission phases with ADAMTS-13 activity between 10% and 50%, with CLIA and ELISA showing significant divergence (P < .001, Cohen's g = 0.34). Consistently, VWF multimers and activity levels exhibited significantly different values between remission samples with ADAMTS-13 activity below 50% and above 50%. In longitudinal analysis of patients with multiple iTTP relapses, positivity to CLIA appears to precede ELISA in predicting exacerbations. Conclusion: While CLIA and ELISA might be interchangeable for assessing ADAMTS-13 activity, they are not equivalent for detecting AAbs, particularly in patients in clinical remission with ADAMTS-13 activity between 10% and 50%.

Quantum Sensing Unravels Antioxidant Efficacy Within PCL/Matrigel Skin Equivalents.

Skin equivalents (SE) that recapitulate biological and mechanical characteristics of the native tissue are promising platforms for assessing cosmetics and studying fundamental biological processes. Methods to achieve SEs with well-organized structure, and ideal biological and mechanical properties are limited. Here, the combination of melt electrowritten PCL scaffolds and cell-laden Matrigel to fabricate SE is described. The PCL scaffold provides ideal structural and mechanical properties, preventing deformation of the model. The model consists of a top layer for seeding keratinocytes to mimic the epidermis, and a bottom layer of Matrigel-based dermal compartment with fibroblasts. The compressive modulus and the biological properties after 3-day coculture indicate a close resemblance with the native skin. Using the SE, a testing system to study the damage caused by UVA irradiation and evaluate antioxidant efficacy is established. The effectiveness of Tea polyphenols (TPs) and L-ascorbic acid (Laa) is compared based on free radical generation. TPs are demonstrated to be more effective in downregulating free radical generation. Further, T1 relaxometry is used to detect the generation of free radicals at a single-cell level, which allows tracking of the same cell before and after UVA treatment.

Relationship between dietary oxidative balance score, anthropometric measurements and socioeconomic factors in women at low risk of cardiovascular disease.

INTRODUCTION: The aim of this study was to investigate the relationship between the dietary oxidative balance score (OBS), an indicator of oxidative stress, anthropometric measures and socioeconomic factors in women at low risk of cardiovascular disease. METHODS: The participants' 3-day dietary intake, demographic information, anthropometric measurements and blood pressure values were recorded, and the Framingham Risk Score (FRS) and OBS values were determined. Oxidative balance score consists of prooxidant and antioxidant scores. Prooxidant scores were calculated from red meat consumption, total iron and polyunsaturated fatty acid intake, alcohol and cigarette consumption parameters, while antioxidant scores were calculated by assessing cruciferous consumption, dietary total vitamin C, vitamin E, ß-carotene, ß-cryptoxanthin, ß-carotene, ß-cryptoxanthin, lycopene, lutein+zeaxanthin and selenium intake. RESULTS: A total of 145 women were included in the study. Education level was associated with anthropometric measurements, income status with antioxidant and prooxidant scores, and exercise status with OBS (p<0.05). Weight, waist, hip, BMI, waist/hip, and waist/height ratio were significantly lower in subjects with low prooxidant score (p<0.05); there was no significant relationship between age, systolic, diastolic, FRS (p>0.05). CONCLUSION: The study, conducted in healthy women, showed that dietary oxidative balance scoring is promising in preventing the development of CVD and reducing the burden of disease, and that prospective cohort studies should be conducted in this area.

Characterization of Orthophosphate and Orthovanadate in Aqueous Solution Using Polarized Raman Spectroscopy.

Polarized Raman spectroscopy was used to analyze aqueous solutions of sodium orthophosphate and orthovanadate over a wide concentration range (0.00891-0.702 mol/L) at 23 °C. The isotropic scattering profiles were obtained by measuring polarized Raman scattering spectra. Furthermore, R-normalized spectra were calculated and presented. The tetrahedral ions, VO43-(aq) and PO43-(aq), demand four Raman active bands which have been subsequently characterized and assigned. For the PO43-(aq) ion, the deformation modes ν2(e) and ν4(f2) appear at 415 and 557 cm-1, and these modes are depolarized. In the P-O stretching region, the strongest Raman band appears at 936.5 cm-1, which is totally polarized with a depolarization ratio (ρ-value) of 0.002. The broad and depolarized mode at 1010 cm-1 constitutes the antisymmetric stretching band ν3(f2). The Raman spectrum of VO43- shows two depolarized deformation modes ν2(e) and ν4(f2) at 327 and 345.6 cm-1, which are severely overlapped. These bands are very weak. The strongest band in the Raman spectrum of VO43-(aq) is the symmetric stretching mode ν1(a1) at 820.2 cm-1 which is totally polarized with a ρ-value at 0.004. The depolarized antisymmetric stretching mode ν3(f2) appeared at 785 cm-1 as a broad and weak band. Both anions are strongly hydrated and showed extensive hydrolysis in an aqueous solution. Orthovanadate is a much stronger base than orthophosphate in aqueous solution. Therefore, a large amount of NaOH was used to suppress the hydrolysis of VO43-(aq) sufficiently, so, it was possible to characterize the VO43- modes. Quantitative Raman spectroscopy was applied to follow the hydrolysis of PO43- over a wide concentration range from 0.00891 to 0.592 mol/L. The hydrolysis data allowed the calculation of the pKa3 value for H3PO4 to be 12.330 ± 0.02 (25 °C). The hydrolysis of the VO43- ion is ∼21 times larger than that of the PO43-. The pKa3 value for H3VO4 is estimated to be 13.65 ± 0.1 (25 °C).

Image dataset for cattle biometric detection and analysis.

The dataset of cattle biometric features is a pivotal asset for improving livestock management and promoting smart agriculture innovation. We obtained a dataset of images capturing the side and back views of Horqin yellow cattle from a farm in eastern Inner Mongolia, China. These data consist of images of 72 free-range Horqin yellow cattle taken with a mobile camera on the grasslands. Each cattle is accompanied by detailed annotations, including oblique body length, withers height, heart girth, hip length, as well as body weight among other crucial data points. This information is considered as high-quality biological feature data. In the field of computer vision, utilizing this dataset can facilitate the construction of deep learning models to develop an automated livestock monitoring system. The aim is to enhance management efficiency and operational effectiveness within the livestock industry. By integrating biological feature information, specific model tools can be employed for body condition assessment and health monitoring research. This approach enables the effective identification and prevention of disease conditions, ultimately providing a deeper level of care and support for livestock welfare and health. The cattle dataset offers support for smart agriculture by enabling the development of intelligent farm management systems. These systems facilitate real-time alerts for livestock health and environmental monitoring. This advancement will drive the modernization and digitization of animal husbandry, fostering agricultural intelligence and sustainable development.

Pain, mindfulness, and placebo: a systematic review.

Introduction: Pain is a complex phenomenon influenced by psychosocial variables, including the placebo effect. The effectiveness of mindfulness-based interventions (MBIs) for pain has been demonstrated in experimental studies and systematic reviews, but the mechanisms of action are only starting to be established. Whether the expectations of individuals experiencing pain can be manipulated during MBIs remains to be systematically evaluated, and what role placebo effects might play remains to be explored. Methods: To evaluate the literature analyzing placebo effects in MBIs for pain, we performed a systematic review based on searches conducted in PubMed, Web of Science, and SCOPUS databases. Our search revealed a total of 272 studies, of which only 19 studies were included (10 acute pain and nine chronic pain), considering the inclusion and exclusion criteria related to expectations and placebo effects. Results: From the 19 included studies, six measured placebo effects only in relation to the pharmacological intervention used in the study and not to an MBI. Discussion: The results of the few studies that focused on the placebo effects of the MBIs indicate that placebo and expectations play a role in the MBIs' effects on pain. Although expectations and placebo effects are frequently discussed in the context of mindfulness and pain research, these results show that these factors are still not routinely considered in experimental designs. However, the results of the few studies included in this systematic review highlight a clear role for placebo and expectancy effects in the overall effects of MBIs for both acute and chronic pain, suggesting that routine measurement and further consideration in future studies are warranted. Additional research in this fascinating and challenging field is necessary to fully understand the connection between MBIs, placebo/expectations, and their effects on pain relief.

CFTR modulators response of S737F and T465N CFTR variants on patient-derived rectal organoids.

BACKGROUND: Predictions based on patient-derived materials of CFTR modulators efficacy have been performed lately in patient-derived cells, extending FDA-approved drugs for CF patients harboring rare variants. Here we developed intestinal organoids from subjects carrying S737F- and T465N-CFTR in trans with null alleles to evaluate their functional impact on CFTR protein function and their restoration upon CFTR modulator treatment. The characterization of S737F-CFTR was performed in two subjects recently assessed in nasal epithelial cells but not in colonoids. RESULTS: Our functional analysis (Ussing chamber) confirmed that S737F-CFTR is a mild variant with residual function as investigated in colonoids of patients with S737F/Dele22-24 and S737F/W1282X genotypes. An increase of current upon Elexacaftor/Tezacaftor/Ivacaftor (ETI) treatment was recorded for the former genotype. T465N is a poorly characterized missense variant that strongly impacts CFTR function, as almost no CFTR-mediated anion secretion was registered for T465N/Q39X colonoids. ETI treatment substantially improved CFTR-mediated anion secretion and increased the rescue of mature CFTR expression compared to either untreated colonoids or to dual CFTR modulator therapies. CONCLUSIONS: Our study confirms the presence of a residual function of the S737F variant and its limited response to CFTR modulators while predicting for the first time the potential clinical benefit of Trikafta® for patients carrying the rare T465N variant.

Deep Indentation Tests of Soft Materials Using Mobile and Stationary Devices.

Measurements of the properties of soft materials are important from the point of view of medical diagnostics of soft tissues as well as testing the quality of food products and many technical materials. One of the frequently used techniques for testing such materials, attractive due to its non-invasive nature, is the indentation technique, which does not puncture the material. The difficulty of testing soft materials, which affects the objectivity of the results, is related to the problems of stable positioning of the studied material in relation to the indentation apparatus, especially with a device held by the operator. This work concerns the comparison of test results using an indentation apparatus mounted on mobile and stationary handles. The tested materials are cylindrical samples of polyurethane foams with three different stiffnesses and the same samples with a 0.5 or 1 mm thick silicone layer. The study presented uses an apparatus with a flat cylindrical indenter, with a surface area of 1 cm2, pressed to a depth of 10 mm (so-called deep tests). Based on the recorded force changes over time, five descriptors of the indentation test were determined and compared for both types of handles. The tests performed showed that the elastic properties of foam materials alone and with a silicone layer can be effectively characterized by the maximum forces during recessing and retraction and the slopes of the recessing and retraction curves. In the case of two-layer materials, these descriptors reflect both the characteristics of the foams and the silicone layer. The results show that the above property of the deep indentation method distinguishes it from the shallow indentation method. The repeatability of the tests performed in the mobile and stationary holders were determined to be comparable.

Severe Microbial Corrosion of L245 Transportation Pipeline Triggered by Wild Sulfate Reducing Bacteria in Shale Gas Produced Water.

The development of pitting corrosion on L245 carbon steel in a culture medium solution containing sulfate-reducing bacteria (SRB) was investigated. The results showed that the occurrence of corrosion in L245 carbon steel is closely linked to the evolution of biofilm and product film. As the test duration extended, overall corrosion was inhibited. Simultaneously, bacteria beneath the film layer promoted the generation and development of pitting corrosion, and the aggregation of bacteria (colonies) led to the aggregation of pitting corrosion.

One-Port Coaxial Line Sample Holder Characterisation Method of Dielectric Spectra.

A technique for solving the one-port closed coaxial transmission line sample holder scattering equation for complex permittivity inversion for lossy materials is presented. A non-linear least-squares procedure is used for the determination of parameters for the specification of the spectral functional form of the complex permittivity. The method allows for accurate retrieval of many low- and high-permittivity dielectric materials in the frequency range of 1 GHz to 3 GHz inserted into the coaxial cell. Using this method, the complex permittivity of a number of liquids and a Maltese soil known as Bajjad soil have been extracted by measurements using a short terminated coaxial transmission line sample holder. The proposed novel inversion method is mainly based on the reflection coefficient of the test material. The measured results of the complex permittivity of liquid dielectrics such as ethanol, methanol, and TX100 are validated and compared with previously published data obtained from measurements made by the National Physical Laboratory (NPL) using a two-port measurement setup made with the same commercial coaxial transmission line sample holder used in the one-port setup. Since the technique allows broadband measurements, it has been used to characterise the soil dielectric spectrum in the frequency range of 1-3 GHz, which is also compared with results from a two-port setup of the same coaxial line. The experimental results are a validation of the proposed approach for different types of materials.