Improve Sample Quality Research Articles

Role of macroscopic on-site evaluation of endoscopic ultrasound-guided fine-needle aspiration/biopsy: Results of a multicentric prospective study.

The concept of macroscopic on-site evaluation (MOSE) was introduced in 2015 when the endoscopist observed better diagnostic yield when the macroscopically visible core on MOSE was superior to 4 mm. Recent studies suggest that MOSE by the endoscopist may be an excellent alternative to rapid on-site evaluation, and some classifications have been published. Few studies have assessed the adequacy of histologic cores in MOSE during endoscopic ultrasound-guided fine-needle aspiration/biopsy (EUS-FNA/FNB). To evaluate the performance of MOSE during EUS-FNA/FNB. This multicentric prospective study was conducted in 16 centers in 3 countries (Egypt, Iraq, and Morocco) and included 1108 patients with pancreatic, biliary, or gastrointestinal pathology who were referred for EUS examination. We prospectively analyzed the MOSE in 1008 patients with available histopathological reports according to 2 classifications to determine the adequacy of the histological core samples. Data management and analysis were performed using a Statistical Package for Social Sciences (SPSS) version 27. A total of 1074 solid lesions were biopsied in 1008 patients with available cytopathological reports. Mean age was 59 years, and 509 patients (50.5%) were male. The mean lesion size was 38 mm. The most frequently utilized needles were FNB-Franseen (74.5%) and 22 G (93.4%), with a median of 2 passes. According to 2 classifications, 618 non-bloody cores (61.3%) and 964 good samples (95.6%) were adequate for histological evaluation. The overall diagnostic yield of cytopathology was 95.5%. The cytological examination confirmed the diagnosis of malignancy in 861 patients (85.4%), while 45 samples (4.5%) were inconclusive. Post-procedural adverse events occurred in 33 patients (3.3%). Statistical analysis showed a difference between needle types (P = 0.035) with a high sensitivity of FNB (97%). The analysis of the relationship between the MOSE-score and the final diagnosis showed a significant difference between the different scores of the MOSE (P < 0.001). MOSE is a simple method that allows endoscopists to increase needle passes to improve sample quality. There is significantly higher FNB sensitivity and cytopathology diagnostic yield with good MOSE cores.

Advances in Oral Exfoliative Cytology: From Cancer Diagnosis to Systemic Disease Detection.

Oral exfoliative cytology has emerged as a valuable tool in the early detection of oral cancer and other systemic diseases. This review comprehensively examines the current applications and recent advancements in oral exfoliative cytology techniques. We analyzed published literature from the past decade, focusing on methodological improvements, diagnostic accuracy, and emerging applications. Key findings include: (1) Enhanced cell collection and preparation methods have significantly improved sample quality and diagnostic reliability. (2) Integration of molecular markers and DNA analysis with traditional cytomorphological assessment has increased diagnostic sensitivity and specificity for oral cancer detection. (3) Novel applications in systemic disease detection, including diabetes and iron overload disorders, demonstrate the expanding utility of this technique. (4) Computer-assisted analysis and deep learning algorithms show promise in improving diagnostic accuracy and efficiency. Despite these advancements, challenges remain in standardization and widespread clinical implementation. This review provides a critical evaluation of oral exfoliative cytology's current status and future potential in oral and systemic disease diagnosis.

Blood self-sampling devices: innovation, interpretation and implementation in total lab automation.

The introduction of the vacuum tube in 1949 revolutionized blood collection, significantly improving sample quality and patient comfort. Over the past 75 years, laboratory diagnostics have evolved drastically, from manual to automated processes, reducing required test volumes by over 1,000 times. Despite these advancements, venous blood collection presents logistical challenges, including centralized scheduling and a large volume of biological waste due to the imbalance between the needed blood volume (often very little) and the collected volume (often in excess). The COVID-19 pandemic further emphasized the need for decentralized healthcare solutions and patient empowerment. Capillary blood collection, widely used in point-of-care testing, offers a promising alternative, particularly for patients facing frequently, or difficulties with, venous sampling. The Leiden University Medical Center in the Netherlands experienced a 15 % reduction in volume of laboratory tests during and after the pandemic, attributed to patient preference for local blood collection and testing. To address these challenges, self-sampling devices are emerging, empowering patients and streamlining sample logistics. However, challenges such as cost, transportation regulations, and sample volume adequacy persists. Robust devices tailored for total lab automation andsustainable practices are crucial for widespread adoption. Despite hurdles, the integration of self-sampling intodiagnostic processes is inevitable, heralding a shift towards patient-centered, proactive healthcare. Practical recommendations include robust device design, ease of use,affordability, sustainability, sufficient quality and acceptability by seamless integration into laboratory workflows. Although obstacles remain, self-sampling represents the future of laboratory diagnostics, offering convenience, cost-effectiveness, interoperability and patient empowerment.

Abstract 2930: Recovery of limited viable cells from low-quality precious samples for scRNA-seq

Abstract Biomarker discovery is a critical milestone in pursuing personalized and targeted cancer treatments, yet it faces formidable challenges hindering success rates. Limited access to high-quality samples restricts in-depth biological investigation, with scarce and compromised viable cells acting as barriers to progress. Levitation Technology™ addresses these challenges by significantly improving sample quality and preserving maximum viable cells for single-cell RNA sequencing (scRNA-seq). This innovative approach overcomes limitations in sample quality and availability and heralds a new era of possibilities, propelling significant advancements in biomarker discovery for personalized cancer treatment. To assess the performance of Levitation Technology using the LeviCell® 1.0 system, 105 cryopreserved samples derived from diseased human tissues were processed by Discovery Life Sciences™. This diverse sample set covered 20 disease indications, including 17 types of cancer. A staggering 70% of the samples (n=74) exhibited cell viability ranging between 14-69%, underscoring the need for enhanced viability for effective scRNA-seq analysis. Notably, 45 of these samples presented fewer than 500,000 cells, a scenario marked by low quality and limited viable cells. Traditional methods fail to recover viable cells from such samples without considerable or complete viable cell loss. After processing the samples with the LeviCell 1.0 system, all samples had improved quality, with an impressive 90% of the most difficult samples (n=40) presenting a viability increase to 70-94%, meeting the minimum quality criteria for scRNA-seq. A notable success story was a particular breast cancer sample with only 31,000 cells and 14% viability. Processing with the LeviCell 1.0 system yielded 13,300 viable cells and a substantial 4.5-fold increase in viability to 64%. Such enhancements in sample quality translate into significant improvements in scRNA-seq data quality, enabling more single-cell data extraction from each invaluable sample. Levitation Technology represents a paradigm shift in sample processing, rescuing even the most challenging samples. This groundbreaking technology maximizes the retention of viable cells while efficiently eliminating dead cells and debris, factors that have traditionally compromised scRNA-seq data quality. By revolutionizing this aspect of sample preparation, Levitation Technology opens up unparalleled opportunities to explore deeper into disease biology, providing a leap forward in biomarker discovery. Citation Format: Camila Egidio, Dinesh Bhosale, Lanxin Shen, Susana Jett, Amir Malek, Teddy de Groot, Suzanne Weaver, Gang Sun, Kevin Travers, Geoff Facer. Recovery of limited viable cells from low-quality precious samples for scRNA-seq [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2930.

Herding behavior, information type, and overconfidence bias: an experimental study on novice investors’ investment decisions

Research aims: By the end of 2023, Indonesian Central Securities Depository data revealed a significant increase in the number of investors dominated by millennial investors (56.41%). They are categorized as novice investors who have distinctive characteristics from professional investors. This study, thus, aims to examine whether herding behavior dominates the characteristics of novice investors and whether information type and overconfidence bias affect the herding behavior of novice investors.Design/Methodology/Approach: This study used a quasi-experimental 2x2 mixed design on 42 student participants who were members of the Capital Market Study Group. The data obtained were then tested using non-parametric statistics.Research findings: The test results uncovered that herding dominated the investment behavior of novice investors. This behavior was supported by the information type that participants paid attention to in making decisions. However, testing for overconfidence demonstrated that this variable was not the cause of novice investors' herding behavior.Theoretical contribution/Originality: The results of this study contribute theoretically to the investment behavior of novice investors by strengthening the argument that they tend to behave herding when making stock investment decisions. Testing with an experimental design allows researchers to confirm that such herding behavior is reinforced by the preference for the information type they use in decision-making. The results also provide insight into the fact that the overconfidence level of novice investors may be different from that of professional investors.Practitioner/Policy implication: The tendency of herding behavior of novice investors needs attention from the Financial Services Authority as a regulator to consider protection for novice investors who dominate the number of investors in the capital market.Research limitation/Implication: The tests in this study employed non-parametric statistics, which are not as good as parametric tests, so the study results should be understood wisely. Future research needs to consider the adequacy of the sample and use capital market groups in several universities to improve sample quality.

Digital transformation and corporate environmental performance: Evidence from Chinese listed companies

This paper constructs a theoretical model to explain the impact of digital technology transformation on corporate environmental performance (CEP). Then, data mining technology is used to crawl the annual report data of Shanghai and Shenzhen A-share listed companies from 2008 to 2021. With the help of text mining analysis, this study quantifies the digital transformation of enterprises and empirically analyses the impact of digital transformation on CEP. The results indicate that digital transformation has significantly improved CEP. The evidence remains valid after a series of robustness tests, including replacing core variables, eliminating the impact of external major events, improving sample quality and instrumental variable regression. Mechanism verification shows that Digital transformation (DT) enhances CEP through ‘green technology upgrading’, ‘increasing external media attention’ and ‘enhancing internal management control’ effects. Heterogeneity analysis shows that DT has a more significant positive impact on non-private, industry technology-intensive, high regional environmental regulation, high energy consumption and high emission CEP, Internet business models are less conducive to improving corporate environmental performance than other digital technologies. Further tests show that resource reallocation improves the industry’s environmental performance and is an important channel for DT to play a catalytic role.

Landslide detection with Mask R-CNN using complex background enhancement based on multi-scale samples

Deep learning has been widely used in landslides detection. However, in practical application, the sample quality often cannot meet the requirements of training models. Some smaller landslides are easy to be omitted if there are multiple landslide objects in one sample. Furthermore, there are some objects with similar shape, texture and colour to landslides (complex backgrounds), such as bare land, roads, water surfaces and artificial buildings. The traditional landslides detection method is easy to confuse landslides and complex backgrounds, which leads to false and omissive detections. To solve the above two problems, a complex background enhancement method with multi-scale samples (MSSCBE) was proposed to improve sample quality. Using the background enhanced samples, the deep learning model can not only learn differences between landslides and complex backgrounds, but also learn the multi-scale features of landslides better. The proposed method was applied to detect landslides that occurred in Jiuzhaigou County, Sichuan Province. Comparative experiments were conducted using Mask R-CNN model. And the model trained with both MSSCBE background enhanced samples and original samples has the best performance. Compared with the model trained with only original samples, Precision, Recall, F1 Score and mIoU is improved by 29.76%, 5.59%, 17.82% and 25.80%, respectively.

Enhanced Energy Storage Capabilities in PbHfO3-Based Antiferroelectric Ceramics through Delayed Phase Switching and Induced Multiphase Transitions

PbHfO3-based antiferroelectric ceramics have garnered considerable attention for their promising applications in energy storage due to their unique phase transition characteristics. However, the inherent conflict between breakdown field and phase...

Sample Preparation for Electron Cryo-Microscopy of Macromolecular Machines.

High-resolution structure determination by electron cryo-microscopy underwent a step change in recent years. This now allows study of challenging samples which previously were inaccessible for structure determination, including membrane proteins. These developments shift the focus in the field to the next bottlenecks which are high-quality sample preparations. While the amounts of sample required for cryo-EM are relatively small, sample quality is the key challenge. Sample quality is influenced by the stability of complexes which depends on buffer composition, inherent flexibility of the sample, and the method of solubilization from the membrane for membrane proteins. It further depends on the choice of sample support, grid pre-treatment and cryo-grid freezing protocol. Here, we discuss various widely applicable approaches to improve sample quality for structural analysis by cryo-EM.

Collection of epididymal semen in the tomcat (Felix catus) by stereomicroscope-aided retrograde flushing (SARF) improves sample quality

In small and laboratory animals epididymal spermatozoa can be collected only by the mincing technique however, blood and cell debris contamination may adversely affect the quality of the samples. This study aimed at performing the retrograde flushing technique, for the first time, in the tomcat. In the first experiment attempts to insert a blunted needle into tomcats’ ductus deferentes were made and the cannulation time and the success rate were recorded. In the second experiment, insertion of the needle into the ductus was carried out under a stereomicroscope for one testis, while the other was submitted to mincing for sperm recovery and the samples obtained from paired testes were compared. In the first study, only twenty-eight percent of the cannulation attempts were successful whereas in the second experiment, 91% of the deferentes were successfully cannulated: 80% of the ducts were cannulated in less than three minutes. The stereomicroscope-aided retrograde flushing samples showed significantly higher sperm viability, motility and velocities, as compared to those resulted from mincing. The domestic cat serves as a model for more than 36 species of wild felids; the developed stereomicroscope-aided retrograde flushing technique has the potential to become the gold standard method for harvesting spermatozoa of endangered species that have a small ductus deferens.

A Sample-Aware Database Tuning System With Deep Reinforcement Learning

Based on the relationship between client load and overall system performance, the authors propose a sample-aware deep deterministic policy gradient model. Specifically, they improve sample quality by filtering out sample noise caused by the fluctuations of client load, which accelerates the model convergence speed of the intelligent tuning system and improves the tuning effect. Also, the hardware resources and client load consumed by the database in the working process are added to the model for training. This can enhance the performance characterization ability of the model and improve the recommended parameters of the algorithm. Meanwhile, they propose an improved closed-loop distributed comprehensive training architecture of online and offline training to quickly obtain high-quality samples and improve the efficiency of parameter tuning. Experimental results show that the configuration parameters can make the performance of the database system better and shorten the tuning time.

High Gas Pressure and High-Temperature Synthesis (HP-HTS) Technique and Its Impact on Iron-Based Superconductors

The high-pressure growth technique generally plays an important role in the improvement of sample quality and the enhancement of various physical and magnetic properties of materials. The high gas pressure technique provides a large sample space (10–15 cm) to grow various kinds of materials. In this paper, we introduce the high gas pressure and high-temperature synthesis (HP-HTS) technique that is present at our institute and is applied to the growth process of different kinds of superconducting materials, particularly iron-based superconductors. More details and the working principle of this HP-HTS technique are discussed. We have also demonstrated the current results based on iron-based superconductors by using this unique HP-HTS technique. These results demonstrate the enhancement of the superconducting properties with improved sample quality compared to the conventional synthesis process at ambient pressure.

A Novel Biopsy Needle with Double Concave-Curved Cutting Edges

BackgroundVacuum-assisted biopsy is a minimally invasive sampling technique that relies on rotational cutting as a major tissue retrieving method. A precise diagnosis of the disease requires large, uncrushed samples, which are impacted by the cutting force of the biopsy needle. ObjectivesThis study proposes a novel needle design with double-concave-curved cutting edges, which is more suited for rotational needle cutting. We aimed to optimize the design so that large, undamaged samples could be extracted with minimal cutting force. Materials and MethodsFive-factor experiments were designed using the Taguchi method. Experiments involving rotational needle insertion and tissue sampling were conducted to examine the effects of these variables on the cutting force and sampling quality, respectively. The relationship between the cutting force and sampling quality was analyzed. ResultsFor needle insertion, the optimal design within the design space demonstrated a marked improvement in cutting force from 1.2107 to 0.1888 N. Furthermore, the optimized double concave-curved needle outperformed the blunt needle under the same needle speeds, showing a 24.4% reduction in cutting force (0.1888 vs. 0.2496 N). Increasing rotation-translation ratio or insertion speed would allow for extracting a larger sample (increased up to 21.95% in weight and 17.21% in total length) but may also increase the rotation speed, resulting in sample fragmentation. To simultaneously improve sampling quality and cutting force, a higher K value, larger rotation-translation ratio, and slower insertion speed are suggested. Based on the conditions examined in this study, the optimal needle configuration should include a sharpened cutting edge with a K value of 0.2, a rotation-translation ratio of 8, and an insertion speed of 1 mm/s.

Monoclinic Distortion in Hyperhoneycomb Kitaev Material β-ZnIrO3 Revealed by Improved Sample Quality

Monoclinic Distortion in Hyperhoneycomb Kitaev Material β-ZnIrO₃ Revealed by Improved Sample Quality

Online Surveys in Latin America

ABSTRACTOnline surveys of public opinion are less expensive and faster to administer than other surveys. However, nonprobability online samples diverge from the gold standard of probabilistic sampling. Although scholars have examined the quality of nonprobability samples in the United States and Europe, we know little about how these samples perform in developing contexts. We use nine online surveys fielded in six Latin American countries to examine the bias in these samples. We also ask whether two common tools that researchers use to mitigate sample bias—post-stratification and sample matching—improve these online samples. We find that online samples in the region exhibit high levels of bias, even in countries where Internet access is widespread. We also find that post-stratification does little to improve sample quality; sample matching outperforms the provider’s standard approach, but the gains are substantively small. This is partly because unequal Internet access and lack of investment in panel recruitment means that providers are unlikely to have enough panelists in lower socioeconomic categories to draw representative online samples, regardless of the sampling method. Researchers who want to draw conclusions about the attitudes or behaviors of the public as a whole in contexts like Latin America still need probability samples.

Efficient Creation and Morphological Analysis of ABC Triblock Terpolymer Libraries

Multiblock copolymers with increasingly complex block sequences─for example, triblock terpolymers─offer unique opportunities to create nanostructured materials, but this potential has been hindered by a vast design space that complicates the exploration of structure–property relationships. Here, we report a versatile and scalable strategy to separate parent ABC and isomeric ACB triblock terpolymers into libraries of fractionated samples spanning a wide range of compositions. Using a combination of controlled polymerization and automated chromatography, the synthesis and separation of less than 10 ABC and ACB parent materials gave rise to over 100 purified triblock terpolymers. Separations follow systematic and predictable trends in volume fraction resulting from an adsorption-based mechanism where chains rich in non-polar blocks elute first, followed by more polar derivatives, yielding fractions with improved purity in composition and molar-mass dispersity. As evidenced by small-angle X-ray scattering, fractionation significantly enhances long-range order compared to as-synthesized parent materials and allows for the definitive identification of various nanoscale morphologies. This user-friendly separation strategy significantly increases the availability of well-defined ABC triblock terpolymer libraries to the polymer community while also improving sample quality and accelerating discovery.

Comparative freezing study of broccoli and cauliflower: Effects of electrostatic field and static magnetic field

The effects of 1, 3, 5 kV/cm electrostatic field (EF) and 2, 5, 8 mT static magnetic field (MF) on the quality of frozen broccoli and cauliflower (B and C) were studied. The freezing parameters were significantly improved by 3, 5 kV/cm EF or 8 mT MF treatment (P < 0.05), a maximum reduction of nucleation time and phase transition time by 20.14 % and 32.09 % was found in 5 kV/cm EF treated cauliflower. EF or MF treatment improved sample quality to some extent, the overall effect of 3 kV/cm EF was the best, which led to a maximum drip loss reduction of 64.3 % in cauliflower, accompanied by lower relative conductivity, higher ascorbic acid and less cell rupture. EF or MF did not significantly reduce the damage of the flavor. MF was less effective than EF in improving the quality of frozen B and C.

Stabilizing invertible neural networks using mixture models

In this paper, we analyze the properties of invertible neural networks, which provide a way of solving inverse problems. Our main focus lies on investigating and controlling the Lipschitz constants of the corresponding inverse networks. Without such a control, numerical simulations are prone to errors and not much is gained against traditional approaches. Fortunately, our analysis indicates that changing the latent distribution from a standard normal one to a Gaussian mixture model resolves the issue of exploding Lipschitz constants. Indeed, numerical simulations confirm that this modification leads to significantly improved sampling quality in multimodal applications.

Flat band carrier confinement in magic-angle twisted bilayer graphene

Magic-angle twisted bilayer graphene has emerged as a powerful platform for studying strongly correlated electron physics, owing to its almost dispersionless low-energy bands and the ability to tune the band filling by electrostatic gating. Techniques to control the twist angle between graphene layers have led to rapid experimental progress but improving sample quality is essential for separating the delicate correlated electron physics from disorder effects. Owing to the 2D nature of the system and the relatively low carrier density, the samples are highly susceptible to small doping inhomogeneity which can drastically modify the local potential landscape. This potential disorder is distinct from the twist angle variation which has been studied elsewhere. Here, by using low temperature scanning tunneling spectroscopy and planar tunneling junction measurements, we demonstrate that flat bands in twisted bilayer graphene can amplify small doping inhomogeneity that surprisingly leads to carrier confinement, which in graphene could previously only be realized in the presence of a strong magnetic field.

Sampling forests with terrestrial laser scanning.

Background and AimsTerrestrial laser scanners (TLSs) have successfully captured various properties of individual trees and have potential to further increase the quality and efficiency of forest surveys. However, TLSs are limited to line of sight observations, and forests are complex structural environments that can occlude TLS beams and thereby cause incomplete TLS samples. We evaluate the prevalence and sources of occlusion that limit line of sight to forest stems for TLS scans, assess the impacts of TLS sample incompleteness, and evaluate sampling strategies and data analysis techniques aimed at improving sample quality and representativeness.MethodsWe use a large number of TLS scans (761), taken across a 255 650-m2 area of forest with detailed field survey data: the Harvard Forest Global Earth Observatory (ForestGEO) (MA, USA). Sets of TLS returns are matched to stem positions in the field surveys to derive TLS-observed stem sets, which are compared with two additional stem sets derived solely from the field survey data: a set of stems within a fixed range from the TLS and a set of stems based on 2-D modelling of line of sight. Stem counts and densities are compared between the stem sets, and four alternative derivations of area to correct stem densities for the effects of occlusion are evaluated. Representation of diameter at breast height and species, drawn from the field survey data, are also compared between the stem sets.Key ResultsOcclusion from non-stem sources was the major influence on TLS line of sight. Transect and point TLS samples demonstrated better representativeness of some stem properties than did plots. Deriving sampled area from TLS scans improved estimates of stem density.ConclusionsTLS sampling efforts should consider alternative sampling strategies and move towards in-progress assessment of sample quality and dynamic adaptation of sampling.