Indirect Methods Research Articles

Experimental Evaluation of Estimating Local Bed Shear Stress Using Log Law in a Straight River Channel

Bed shear stress is a critical parameter in riverine environments, directly influencing sediment transport, erosion, deposition, and flow dynamics. However, direct measurement of bed shear stress in natural rivers is nearly impossible, and estimating bed shear stress by extrapolating the Reynolds stress profile, though known for accuracy, faces practical limitations due to the challenges of measuring turbulence in natural rivers. As alternatives, indirect methods, such as global bed shear stress estimation based on bed slope and hydraulic radius (assuming uniform flow) and local bed shear stress estimation through regression of velocity profiles using the log law, have been employed. The estimation of local bed shear stress using the log law has primarily been derived from laboratory flow conditions due to the limitations in observing detailed turbulence in field conditions. Consequently, the applicability of the log-law method under field conditions has not been sufficiently evaluated. This study aims to assess local bed shear stress using the log law through a dedicated field experiment in a specific river condition, comparing it with methods utilizing the Reynolds stress profile. The experiment was conducted in a straight river channel with a width of approximately 6.5 m, a depth of 0.61 m, and a mean flow velocity of 0.56 m/s. A total of 197 points of regularly distributed velocity and turbulence data for the given cross-section were acquired using micro-acoustic Doppler velocimeter measurements with a duration of 90 s. We found that the log-law method overestimated local bed shear stress by an overall factor of 2.3 compared to the method using Reynolds stress profiles. Thus, the experimental results conclusively indicate that local bed shear stress estimated from the log law in natural river conditions could be overestimated. However, additional research is needed under more diverse flow and geometric conditions to develop a correction formula for applying the log law in estimating local bed shear stress.

The equivalent source method is an indirect boundary element method with an implicit Voronoi mesh

The Equivalent Source Method (ESM) consists of modeling the acoustical field radiated or scattered from an object by a set of radiating monopole sources located below its surface. While highly efficient for modeling the scattered field by a smooth object, ESM becomes less effective in representing acoustic diffraction from sharp edges. In this article, ESM is understood as an approximation to the single layer integral equation. In this framework, ESM belongs to the family of Indirect Boundary Element Methods (BEM) with an implicit surface mesh slightly below the object surface, and a zero order integration scheme on each element of the mesh. This implicit mesh is well approximated by the Voronoi diagram associated to the source distribution. This formalism establishes a strong link between these two widely used methods (ESM and BEM) and allows the construction of hybrid methods that can combine performances of both methods. On the first hand, a new hybrid method able to model edge diffraction while remaining as computationally efficient as ESM is developed. In this method, labeled “BEM Voronoi”, equivalent sources are positioned on the surface’s object rather than below it and singularities are handled with the integral formulation. On the other hand, a set of new hybrid methods which combines ESM with higher order integration scheme is constructed. Performances of the new methods developed in this paper are numerically compared to each other and to Finite Element simulations (used as a reference) for modeling scattering from an object excited by a plane wave. Each hybrid model is tested on multiple configurations involving two sets of boundary conditions (rigid and elastic objects respectively) successively immersed in two different external environments (water and air) and for both smooth and a sharp-edged objects. The results show that the hybrid method “BEM Voronoi” better handles edge diffraction than conventional ESM, at a much lower computational cost (implementation of BEM Voronoi is 50 times faster than conventional BEM implementation).

Should we depend on reference intervals from manufacturer package inserts? Comparing TSH and FT4 reference intervals from four manufacturers with results from modern indirect methods and the direct method.

Correct interpretation of thyroid function tests relies on correct reference intervals (RIs) for thyroid-stimulating hormone (TSH) and free thyroxine (FT4). ISO15189 mandates periodic verification of RIs, but laboratories struggle with cost-effective approaches. We investigated whether indirect methods (utilizing historical laboratory data) could replace the direct approach (utilizing healthy reference individuals) and compared results with manufacturer-provided RIs for TSH and FT4. We collected historical data (2008-2022) from 13 Dutch laboratories to re-establish RIs by employing indirect methods, TMC (for TSH) and refineR (for FT4). Laboratories used common automated platforms (Roche, Abbott, Beckman or Siemens). Indirect RIs (IRIs) were determined perlaboratory per year and clustered per manufacturer (>1.000.000 data points per manufacturer). Direct RIs (DRIs) were established in 125 healthy individuals per platform. TSH IRIs remained robust over the years for all manufacturers. FT4 IRIs proved robust for three manufacturers (Roche, Beckman and Siemens), but the IRI upper reference limit (URL) of Abbott showed a decrease of 2 pmol/L from 2015. Comparison of the IRIs and DRIs for TSH and FT4 showed close agreement using adequate age-stratification. Manufacturer-provided RIs, notably Abbott, Roche and Beckman exhibited inappropriate URLs (overall difference of 0.5-1.0 µIU/mL) for TSH. For FT4, the URLs provided by Roche, Abbott and Siemens were overestimated by 1.5-3.5 pmol/L. These results underscore the importance of RI verification as manufacturer-provided RIs are often incorrect and RIs may not be robust. Indirect methods offercost-effective alternatives for laboratory-specific or platform-specific verification of RIs.

High piezoelectric performance in lead-free (K, Na)NbO3 ceramics under a low driving field

In this work, lead-free (K0.485Na0.485Li0.03)Nb0.8Ta0.2O3 composition was designed to control the orthorhombic-tetragonal phases boundary near the room temperature as confirmed by Rietveld analysis, high-angle annular dark field scanning transmission electron microscopy, and temperature dependent dielectric constant. A comparative study of the direct and indirect synthesis methods was carried out and their functional properties were optimized as a function of sintering temperature (Ts) and dwell time. Here, we achieved a large dynamic piezoelectric constant (d33*) of 510 pm/V under a very low electric field of 15–30 kV/cm. Moreover, an enhanced static piezoelectric constant (d33) of 335 pC/N was obtained with a high Curie temperature (TC) of 315 °C. The large d33 and d33* simultaneously with high TC in a single composition are promising results in lead-free polycrystalline ceramics. The strategic design of this work opens a new door for the possible development of novel functional materials for device applications.

Enhancing Quality Control in Battery Component Manufacturing: Deep Learning-Based Approaches for Defect Detection on Microfasteners

The management of product quality is a crucial process in factory manufacturing. However, this approach still has some limitations, e.g., depending on the expertise of the engineer in evaluating products and being time consuming. Various approaches using deep learning in automatic defect detection and classification during production have been introduced to overcome these limitations. In this paper, we study applying different deep learning approaches and computer vision methods to detect scratches on the surface of microfasteners used in rechargeable batteries. Furthermore, we introduce an architecture with statistical quality control (SQC) to continuously improve the efficiency and accuracy of the product quality. The proposed architecture takes advantage of the capability of deep learning approaches, computer vision techniques, and SQC to automate the defect detection process and quality improvement. The proposed approach was evaluated using a real dataset comprising 1150 microfastener surface images obtained from a factory in Korea. In the study, we compared the direct and indirect prediction methods for predicting the scratches on the surface of the microfasteners and achieved the best accuracy of 0.91 with the indirect prediction approach. Notably, the indirect prediction method was more efficient than the traditional one. Furthermore, using control charts in SQC to analyze predicted defects in the production process helped operators understand the efficiency of the production line and make appropriate decisions in the manufacturing process, hence improving product quality management.

Comparison between direct and indirect "digital image" dental visual shade matching considering the effect of clinical experience and gender.

Shade matching is an essential procedure to obtain an esthetic prosthesis. The Direct Visual Shade Matching (DSM) method using shade guides is the most used method by dentists. However, The Indirect Visual Digital Shade Matching (ISM) method based on digital imaging is concerned to be reliable and useful in determining shade matching in dental practice. Several factors such as method, clinical experience, and gender can affect the success of shade matching. This study aimed to compare these two methods and evaluate the effect of experience and gender on the results. Three volunteers' maxillary central incisor teeth were evaluated using (DSM) and (ISM) methods by 87 examiners (42 males, 45 females). These examiners were further divided into three groups based on their clinical experience: Undergraduate Preclinical Dental Students (UPDS) with 31 examiners, Undergraduate Clinical Dental Students (UCDS) with 34 examiners, and Postgraduate Dental Students from the Department of Prosthodontics (PDS) with 22 examiners. The spectrophotometer device results of three teeth were considered as a reference for shade matching. Statistical analyses of the data were performed using Kruskal-Wallis, Mann-Whitney U, and Chi-square tests. No significant difference was found between indirect and direct methods according to Perfect Matches (p > 0.05). However, according to Shade Matching Deviation Score (SMDS) values a statistically significant difference was found between the two methods where the best result was obtained with the ISM method (p < 0.05). There was a significant difference between the PDS group and the other two groups in terms of clinical experience (p < 0.05). There was no significant difference between gender groups (p > 0.05). Digital images, captured under standardized lighting conditions, may serve as a reliable alternative method for direct shade matching. The (ISM) method requires a camera, related accessories, and computer skills. However, as these tools are commonly available nowadays, the focus for practitioners should be on effectively learning and applying these tools to achieve the best results. While clinical experience plays a significant role in the shade matching process, gender does not appear to have a substantial influence. This study found no significant differences between the (DSM) and (ISM) methods, leaving the clinical relevance of this method open to debate. However, the ISM method yielded superior responses. Despite requiring specialized tools, conditions, and training, the widespread use of cameras and computers in modern clinics makes the necessary equipment and software readily available. This method enhances clinician-technician communication, potentially improving prosthesis esthetics and patient satisfaction, especially for less experienced clinicians or those with color deficiencies. Further research is crucial to determine its clinical significance.

An original set of nanometer-scale mineralogical analyses of cookeite and the implications for Li enrichment: No. 21 coal, Mengjin Mine, western Henan

Critical elements in coal deposits, such as lithium (Li), have attracted attention recently due to their economic value. Many studies have suggested that the high enrichment of Li in coals is predominantly associated with cookeite, a Li–bearing chlorite mineral of hydrothermal origin. However, the identification of cookeite in coal has primarily relied on indirect methods, owing to the low atomic number of Li, which presents significant challenges for precise observation. The Shanxi Formation No. 21 coal in North China is enriched in Li. This study established a nanometer–scale mineralogical analytical technique (including high–resolution transmission electron microscopy (HR–TEM), fast Fourier transformation (FFT), and standard mineral simulation single-crystal diffraction (SSCD)) for the identification of the cookeite and evaluated the Li enrichment mechanism and recovery in this coal (low–volatile bituminous to semi–anthracite) based on a model for the Li mineralization. The Li content of the No. 21 coal ranges from 25.2 to 203 ppm. The Li content shows a strong correlation with the ash yield, Al2O3, SiO2, and detrital elements, indicating a dominant aluminosilicate affinity and detrital origin. The major aluminosilicate minerals in coal are kaolinite, chlorite, and illite. The geochemical indicators (the Al2O3/TiO2 ratio and its relationships with the Zr/TiO2, Nb/Y, and Nb/Yb ratios) indicate that the sediment sources are determined to be intermediate–felsic igneous rocks, probably the Mesoproterozoic moyite (a type of K– feldspar granite) in the Yinshan Oldland. Additionally, the coal can be divided vertically into three sections (Sections I, II, and III), corresponding to three stages of peat formation. Overall, from Section I to Section III, the degree of detrital input increased, and the groundwater and marine influences strengthened and weakened, respectively. Section II exhibits anomalous Li enrichment mainly associated with reducing environments and the geochemical barrier caused by the interaction between infiltrating seawater and groundwater. The detrital kaolinite assemblage with authigenic minerals such as secondary REE–rich minerals (bastnasite), chamosite, and quartz, as well as the REY enrichment patterns, suggests that the No. 21 coals, mainly Section II, may have existed the hydrothermal alteration. Cookeite is identified primarily in Section II and coexists with kaolinite based on TEM observations, suggesting that the cookeite is of hydrothermal origin and formed from pre–existing Li–rich kaolinite. Most samples from Section II meet the mining grade of Be–Li–Nb–Ta ore deposits (Li2O > 0.2%). Thus, this study offers valuable insights into the extraction and recovery of Li from coal combustion residues, particularly when cookeite is the primary Li–bearing mineral.

Abstract B033: Direct and sensitive in-situ detection of DNA breaks by STRIDE and its potential as a new biomarker

Abstract DNA damage is usually detected using indirect methods which require active signaling and triggered DNA repair mechanisms. These methods, although relatively sensitive, are prone to false (positive or negative) results. Methods for direct DNA damage detection, on the other hand, suffer from low sensitivity or require DNA isolation, what can result in misleading artefactual readouts of the analysis. Here we present a method called STRIDE (SensiTive Recognition of Individual DNA Ends), which allows for specific, very sensitive in-situ detection of DNA breaks. This fluorescence-based method, in its two variants (dSTRIDE and sSTRIDE), allows selective labelling of double-or single-strand breaks, respectively. STRIDE enables highly sensitive and specific detection and quantification of single and double-strand DNA breaks in cultured cells and FFPE human tissues, both PBMCs as well as solid tumors. STRIDE is superior to classic methods used to measure DNA damage, as it combines a direct detection that is independent of DNA repair mechanisms with an unprecedented sensitivity. With its versatility it can be used in any type of biological material, including liquid biopsies as well as different types of tumors. STRIDE has the potential to become a very useful biomarker reporting about the efficiency of therapies based on DNA damage induction, such as DNA repair inhibitors or radiotherapy. Citation Format: Kamil Solarczyk, Brian Patterson. Direct and sensitive in-situ detection of DNA breaks by STRIDE and its potential as a new biomarker [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: DNA Damage Repair: From Basic Science to Future Clinical Application; 2024 Jan 9-11; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2024;84(1 Suppl):Abstract nr B033.

Comparative efficacy and safety of tisagenlecleucel and axicabtagene ciloleucel among adults with r/r follicular lymphoma

Regulatory approvals of tisagenlecleucel (tisa-cel) and axicabtagene ciloleucel (axi-cel) have established the feasibility of chimeric antigen receptor T-cell therapies for the treatment of adults with relapsed or refractory follicular lymphoma (r/r FL). This study used individual patient data from ELARA (tisa-cel) and aggregate published patient data from ZUMA-5 (axi-cel) to compare efficacy and safety outcomes in r/r FL using matching-adjusted indirect comparison methods. After adjustment for baseline differences in the trial populations, the results suggested that tisa-cel (n = 52), compared with axi-cel (n = 86), had similar effects on overall response rate (91.2% vs. 94.2%; p = .58), complete response rate (74.0% vs. 79.1%; p = .60), progression-free survival (HR [95% CI]: 0.8 [0.4, 1.9]; p = .67), and overall survival (HR [95% CI]: 0.5 [0.2, 1.5]; p = .21). Tisa-cel (n = 53) was associated with better safety outcomes than axi-cel (n = 124), reflected by lower rates of any grade and grade ≥3 cytokine release syndrome and neurological events.

Effects of an empathy enhancement program using patient stories on attitudes and stigma toward mental illness among nursing students.

This study aims to explore the impact of an empathy intervention through patients' stories and investigate its impact on attitudes and stigma toward mental illness among nursing students prone to hold prejudices against this condition. Using a quasi-experimental pretest-posttest design, this study focused on nursing students and examined the effects of an empathy enhancement program targeting individuals with mental illnesses on communication, social distance, and prejudice. Ninety third-year nursing students from S and C cities and H and C universities enrolled in psychiatric nursing courses participated in the study. The intervention lasted 4 weeks and used the patient's story to facilitate a participatory approach to understanding the patient's life and encouraging mutual growth and expansion of consciousness in the therapeutic relationship. Age was treated as a covariate and analyzed using a two-way repeated-measure analysis of covariance. The Empathy Enhancement Program Using Patient Stories (EEP-PS) group and the clinical practicum group showed no significant differences in communication, social distance, and empathy scores between the two groups or across different time points. However, variations were observed when examining specific subdomains within each group and across time points. Informative communication (F = 10.34, p = 0.002) and affiliative communication (F = 21.60, p < 0.001), which are subcategories of communication, increased significantly in the posttest compared to the pretest. Among social distances, interpersonal-physical distance decreased significantly in the posttest compared to the pretest (F = 31.02, p < 0.001). Prejudice of incompetence (F = 6.52, p = 0.012) and prejudice of risk (F = 14.37, p < 0.001) were significantly lower in the posttest than in the pretest. Both the EEP-PS and clinical practicum groups experienced improvements in communication, social distance, and prejudice toward individuals with mental illness. This study suggests that direct patient interactions and the use of patient narratives as indirect methods are effective approaches for enhancing attitudes and reducing stigma toward mental illness among nursing students.

ETIKA DAN SOLIDARITAS SOSIAL DALAM GERAKAN BERBAGI NASI DI BANDUNG: MEMBANGUN JIWA SOLIDARITAS MASYARAKAT KOTA BANDUNG

This research aims to determine the ethics and social solidarity carried out in the Sharing Rice movement in Bandung to build high social solidarity, especially in the community in Bandung City. In this research, data collection was used using indirect research methods. Data analysis starts from understanding the theory and case studies, then conclusions and outlines are drawn from the case studies. The results of this research show that the ethics and social solidarity that exist in the case of the Sharing Rice movement are very good and this is also the right opportunity and means for the community, especially the city of Bandung, who want to increase their spirit of solidarity, either on social media or directly.

Comparison of three indirect methods for density estimation of the wild boar (Sus scrofa) in different habitats in South Korea

Increasing human-wild boar conflicts in South Korea have led to a demand for effective management strategies. Absolute abundance, rather than relative indices, is needed for the long-term monitoring and population control of wild boars. Indirect methods for density estimation have become increasingly popular because they are cost-effective and do not have the risk of capture probability bias. We compared three indirect methods, including the non-invasive capture-recapture model (NICRM), random encounter model (REM), and fecal standing crop (FSC), in two different sites characterized by specific habitats (urban and agricultural environments). NICRM and REM reflected population fluctuation and hunting intensity assumptions at both sites; however, FSC did not reflect the latter. While using NICRM, efforts are needed for achieving a low genotyping error rate; this model would achieve more reliable results in low-density areas. REM with accurate parameter information (i.e., daily range, detection zone, and camera placement) could be the most effective density estimation method for long-term monitoring in South Korean environments. Conversely, FSC may not be recommended because of many factors, such as decomposition rate, rainfall, biased distribution of feces that might affect pellet groups. Additionally, the density estimates from this study can provide information for developing effective management strategies in South Korean environments.

Feasibility of direct brain 18F-fluorodeoxyglucose-positron emission tomography attenuation and high-resolution correction methods using deep learning.

To develop the following three attenuation correction (AC) methods for brain 18F-fluorodeoxyglucose-positron emission tomography (PET), using deep learning, and to ascertain their precision levels: (i) indirect method; (ii) direct method; and (iii) direct and high-resolution correction (direct+HRC) method. We included 53 patients who underwent cranial magnetic resonance imaging (MRI) and computed tomography (CT) and 27 patients who underwent cranial MRI, CT, and PET. After fusion of the magnetic resonance, CT, and PET images, resampling was performed to standardize the field of view and matrix size and prepare the data set. In the indirect method, synthetic CT (SCT) images were generated, whereas in the direct and direct+HRC methods, a U-net structure was used to generate AC images. In the indirect method, attenuation correction was performed using SCT images generated from MRI findings using U-net instead of CT images. In the direct and direct+HRC methods, AC images were generated directly from non-AC images using U-net, followed by image evaluation. The precision levels of AC images generated using the indirect and direct methods were compared based on the normalized mean squared error (NMSE) and structural similarity (SSIM). Visual inspection revealed no difference between the AC images prepared using CT-based attenuation correction and those prepared using the three methods. The NMSE increased in the order indirect, direct, and direct+HRC methods, with values of 0.281×10-3, 4.62×10-3, and 12.7×10-3, respectively. Moreover, the SSIM of the direct+HRC method was 0.975. The direct+HRC method enables accurate attenuation without CT exposure and high-resolution correction without dedicated correction programs.

Principles of Indirect Co-culture Method Using Transwell.

The co-culture method is a simple type of cell culture method used to evaluate the effects of communication between various types of cells in an in vitro setting. In the co-culture method, two or more eukaryotic cell types, or eukaryotic and prokaryotic cells, are cultured together. The co-culture method reflects in vivo cell behaviors and thereby emerges as a pivotal technique with diverse applications in cancer research and cell biology. Two categories of co-culture methods (indirect methods and direct methods) are well known. Direct co-culture methods allow physical contact between the various cell types (juxtacrine signaling). In indirect methods, cells are physically separated into two different populations (for example, using a Transwell) that allow communication only via secretory factors (paracrine signaling). Herein, we focus on the principles of the indirect co-culture method. Nowadays, this method is used to explore the effects of mesenchymal stem cell (MSC) secretome on cancer cells. These studies have unveiled intricate cell behavior dynamics, demonstrating how the MSC secretome influences cancer cell proliferation, invasion, apoptosis, and polarity.

The role of norm-referenced regulation and indirect methods in optimizing law and reducing regulatory risks

The subject of the study is public relations in dynamically developing areas, where direct methods of public administration and traditional legal tools show their ineffectiveness. The purpose of the article is to develop an approach to the applicability of indirect methods in administrative and legal regulation in the context of the transition to Industry 4.0. The research was carried out on the basis of an interdisciplinary approach using method of system analysis and the dogmatic method. As a result of the study, it was concluded that increased government influence on the economy led to the formation of a process approach to administrative and legal regulation. However, the use of this approach assumes that identifying a defect is a norm that cannot, as a general rule, entail negative consequences for an economic entity. This feature is dissonant with the approach to legal regulation, and in a process sense it contains the less social value and carries the more threats, risks and costs, the more detailed it is. Overcoming the negative consequences of direct regulation is possible by using indirect methods of public administration, in which the solidarity of non-state actors with state goals is achieved through economic interest. Non-state regulation not only includes rule-making and control, but also requires providing incentives. Norm-referenced regulation is used in semi-formalized areas in which the state does not have awareness and effective tools for influence, but can use an incentive mechanism in areas of interest to the private sector. In such cases, the emphasis shifts from state to non-state regulation. In the context of the transition to Industry 4.0, the state will transfer regulatory functions to the private sector for self-regulation and local regulation with indirect influence from the state.

Detour to success: photoswitching via indirect excitation.

Photoswitchable molecules that undergo nanoscopic changes upon photoisomerisation can be harnessed to control macroscopic properties such as colour, solubility, shape, and motion of the systems they are incorporated into. These molecules find applications in various fields of chemistry, physics, biology, and materials science. Until recently, research efforts have focused on the design of efficient photoswitches responsive to low-energy (red or near-infrared) irradiation, which however may compromise other molecular properties such as thermal stability and robustness. Indirect isomerisation methods enable photoisomerisation with low-energy photons without altering the photoswitch core, and also open up new avenues in controlling the thermal switching mechanism. In this perspective, we present the state of the art of five indirect excitation methods: two-photon excitation, triplet sensitisation, photon upconversion, photoinduced electron transfer, and indirect thermal methods. Each impacts our understanding of the fundamental physicochemical properties of photochemical switches, and offers unique application prospects in biomedical technologies and beyond.

RNA sequencing analysis of early-stage atherosclerosis in vascular-on-a-chip and its application for comparing combustible cigarettes with heated tobacco products

Our previous study showed promising results in replicating early-stage atherosclerosis when vascular endothelial cells (VECs) were exposed to cigarette smoke (CS) extract via M0 macrophages. We used an organ-on-a-chip system as an alternative to animal testing to model atherosclerosis, which is a complex disease involving endothelial and immune cell communications. By incorporating macrophages into the vascular-on-a-chip system, we aimed to mimic the indirect effects of inhalable substances, such as CS, on VECs. In the current study, we further examined the suitability of our in vitro system for mimicking early-stage atherosclerosis by transcriptomic analyses of VECs exposed to CS directly or indirectly via macrophages. We also incorporated M1 macrophages to replicate a preexisting inflammatory state. We found a greater number of differentially expressed genes (DEGs) in direct exposure methods than indirect exposure methods. However, a pathway analysis showed that the direct exposure of CS to VECs primarily caused cell death-related pathway alterations, and the “Atherosclerosis Signaling” pathway was predicted to be negatively regulated. Indirect exposure via M0 macrophages similarly showed that the identified DEGs were related to cell death, while the “Atherosclerosis Signaling” pathway was predicted to be activated. In contrast, cell death-related pathway alterations were not observed by indirect exposure of CS to VECs via M1 macrophages, but the pathway perturbations were similar to a pro-inflammatory positive control. In addition, the “Atherosclerosis Signaling” pathway was predicted to be activated in VECs that were indirectly exposed to CS via M1 macrophages. These results suggest that M0 or M1 macrophages contribute to atherogenic transcriptomic changes in VECs, although they affect cell death-related pathways differently. We also used indirect exposure methods to compare the effects of CS and heated tobacco product (HTP) aerosol. Notably, gene expression changes related to atherosclerosis were less pronounced in HTP aerosol-exposed VECs than CS. Our study highlights the utility of the vascular-on-a-chip system with indirect exposure of CS extract via macrophages for replicating atherogenesis and suggests a reduced risk potential of the HTP. This research contributes to advancing alternatives to animal testing for toxicological and disease modeling studies.

The effect of job stress on the quality of life of commercial pilots: Testing the mediating effects of mindfulness and job satisfaction

AbstractThe commercial pilots responsible for aircraft and passenger safety are exposed to various environmental job stresses. This study investigates the relationship between job stress and the quality of life of commercial pilots, and examines the mediating effects of mindfulness and job satisfaction in the relationship between job stress and quality of life. The results show that the job stress aced by commercial pilots has a negative impact on quality of life, and that mindfulness and job satisfaction partially mediates this stress. However, despite the mediating effects of mindfulness and job satisfaction, there is a need for a way to reduce job stress more directly. These results indicate the need for various strategies, including direct and indirect methods, to reduce job stress among commercial pilots, as this is directly related to safety.

Feasibility and safety of ultrasound-guided percutaneous transhepatic measurement of portal venous pressure.

The measurement of portal venous pressure (PVP) has been extensively studied, primarily through indirect methods. However, the potential of ultrasound-guided percutaneous transhepatic PVP measurement as a direct method has been largely unexplored. This study aimed to investigate the accuracy, safety, and feasibility of this approach. In vitro, the experiment aimed to select a needle that could accurately transmit pressure, had a small inner diameter and was suitable for liver puncture, and performed on 20 healthy New Zealand white rabbits. An ultrasound-guided percutaneous transhepatic portal vein puncture was undertaken to measure PVP. Additionally, free hepatic venous pressure (FHVP) and wedged hepatic venous pressure (WHVP) were measured under digital subtraction angiography (DSA). The correlation between the two methods was assessed. Enroll study participants from October 18, 2023 to November 11, 2023 with written informed consent. Five patients were measured the PVP under ultrasound guidance before surgery to determine the feasibility of this measurement method. There was no significant difference in the results obtained using 9 different types of needles (P > 0.05). This demonstrated a great repeatability (P < 0.05). The 22G chiba needle with small inner diameter, allowing for accurate pressure transmission and suitable for liver puncture, was utilized for percutaneous transhepatic PVP measurement. There were positive correlations between PVP and HVPG (r = 0.881), PVP and WHVP (r = 0.709), HVPG and WHVP (r = 0.729), IVCP and FHVP (r = 0.572). The PVP was accurately and safely measured in 5 patients with segmental hepatectomy. No complications could be identified during postoperative ultrasound. Percutaneous transhepatic portal venous puncture under ultrasound guidance is accurate, safe and feasible to measure portal venous pressure. This study has been registered in the Chinese Clinical Trial Registry with registration number ChiCTR2300076751.

Customizable ligand exchange on the surface of gold nanotriangles enables their application in LSPR-based sensing.

Nanomaterials made of noble metals have been actively utilized in sensorics and bioanalytics. Nanoparticles of anisotropic shapes are promising for increasing sensitivity due to the generated hotspots of electron density. Such structures can be effectively manufactured by a relatively accessible colloidal synthesis. However, the shape control requires the attachment of a surfactant on specific crystal facets during their growth. Commonly used cetrimonium halides form a closely packed bilayer, lowering the surface accessibility for subsequent (bio)functionalization steps. While there are numerous studies on functionalizing gold nanospheres, novel materials, such as nanotriangles (AuNTs), often require thorough studies to adapt the existing procedures. This is mainly caused by the incomplete characterization of initial nanoparticle colloids in empirically developed protocols. Herein, we report a rational approach utilizing the surface area of AuNTs as a function of both their dimensions and concentration, determined with an express UV-VIS analysis. We demonstrate its efficiency for the exchange of cetyltrimethylammonium chloride (CTAC) with polystyrene sulfonate (PSS) and with biocompatible citrate using direct and indirect methods, respectively. Fourier-transform infrared spectroscopy unequivocally proves the ligand exchange. Such functionalization allows evaluating the bulk refractive index sensitivity of AuNTs as a measure of their potential in LSPR-based sensing.