Direct Identification Research Articles

Failure Forensics of Shaped PDC Cutters Using Image Analysis and Deep Learning

Summary One of the major advances in polycrystalline diamond compact (PDC) bits in the last 10 years is the global adoption of 3D-shaped PDC cutters. By manipulating the cutter shape based on the understandings of cutter–rock interaction mechanisms, the cutting efficiency and mechanical properties of PDC cutters have been greatly improved. Ongoing innovations in 3D-shaped PDC cutter technology are critical to overcoming the more and more challenging formations in ultradeep wells, such as the 10 000-m-deep wells being drilled in China. Such an important role for 3D-shaped PDC cutters in oil and gas drilling applications necessitates a complete and effective failure analysis method. However, the current International Association of Drilling Contractors (IADC) dull grading cannot fulfill this objective. It is out of date in judging the damages to PDC bits and exhibits more limitations in addressing the unique challenges presented by complicated cutter shapes. To address this issue, an intelligent recognition model for PDC bit damage identification was developed based on the image analysis technology and the YOLOv7 algorithm. More than 10,000 dull bit images were used to train and validate this intelligent recognition model, which were collected from 363 PDC bits that suffered different degrees of damage after being used to drill 185 wells in the Sinopec Shengli Oilfield. Compared to the existing models, the developed intelligent recognition model has several notable contributions. First, the developed model is capable of recognizing the damages of various shaped PDC cutters commonly used by the global bit manufacturers, enabling a more accurate assessment of the failure behaviors of shaped cutters and their bits. The detection accuracy of the developed model exceeds 80% based on the confusion matrix. The recognition results by the developed artificial intelligence (AI) model are consistent with the actual failure modes judged by experienced drilling engineers. Second, the developed AI model provides direct qualitative identification of the failure modes and failure reasons for both cutters and PDC bits rather than the quantitative evaluation of the missing diamond layer used by IADC dull grading. Furthermore, the developed model eliminates the effect of reclaimed cutters on the AI detection results based on the implicit use of spatial cues in the YOLOv7 algorithm. The intelligent recognition model developed in this work can provide reliable and valuable guidance for the post-run evaluation, the bit selection for the next run, and the iterative optimization of bit design.

Direct identification of pathogens via microbial cellular DNA in whole blood by MeltArray.

Rapid identification of pathogens is critical for early and appropriate treatment of bloodstream infections. The various culture-independent assays that have been developed often have long turnaround times, low sensitivity and narrow pathogen coverage. Here, we propose a new multiplex PCR assay, MeltArray, which uses intact microbial cells as the source of genomic DNA (gDNA). The successive steps of the MeltArray assay, including selective lysis of human cells, microbial cell sedimentation, microbial cellular DNA extraction, target-specific pre-amplification and multiplex PCR detection, allowed the detection of 35 major bloodstream infectious pathogens in whole blood within 5.5 h. The limits of detection varied depending on the pathogen and ranged from 1 to 5 CFU/mL. Of 443 blood culture samples, including 373 positive blood culture samples and 70 negative blood culture samples, the MeltArray assay showed a sensitivity of 93.8% (350/373, 95% confidence interval [CI] = 90.7%-96.0%), specificity of 98.6% (69/70, 95% CI = 91.2%-99.9%), positive predictive value of 99.7% (95% CI = 98.1%-99.9%), and negative predictive value of 75.0% (95% CI = 64.7%-83.2%). The MeltArray detection results of 16 samples differed from MALDI-TOF and were confirmed by Sanger sequencing. Further testing of 110 whole blood samples from patients with suspected bloodstream infections using blood culture results revealed that the MeltArray assay had a clinical sensitivity of 100% (9/9, 95% CI = 62.8%-100.0%), clinical specificity of 74.5% (70/94, 95% CI = 64.2%-82.7%), positive predictive value of 27.3% (95% CI = 13.9%-45.8%), and negative predictive value of 100.0% (95% CI = 93.5%-100.0%). Compared with metagenomic next-generation sequencing, the MeltArray assay displayed a positive agreement of 85.7% (6/7, 95% CI = 42.0%-99.2%) and negative agreement of 100.0% (4/4, 95% CI = 39.6%-100.0%). We conclude that the MeltArray assay can be used as a rapid and reliable tool for direct identification of pathogens in bloodstream infections.

Ceftazidime Dosage Investigation using Differential Pulse Polarography for Pharmaceuticals

An accurate direct DPP identification of ceftazidime has been made for use in drug discovery and validation. The results showed that a mercury drop of 3 mm3, an acidic medium consisting of a KH phthalate plus HCl buffer solution at pH 2, and 1 ml of NH4Cl, 1 M as a supporting electrolyte were optimal for ceftazidime analysis.Ceftazidime exhibited two peaks, the first at - 0.67V and the second at - 1.06V. For the determination of an unknown concentration, a standard graph of ceftazidime in concentrations ranging from 8.410-6 M to 2.610-5 M was developed. The reliability and accuracy of this technique for analysing the analyte were assessed. For ceftazidime laboratory samples, the SD was 0.1885 and the RSD% did not go above 4.573% at a concentration of 4.6 μg.ml-1, 8.410-6 M, and at a concentration of 8.5 μg.ml-1, 1.510-5 M, the SD was 0.35645 and the RSD% did not go over 4.345%. The peak potential Ep, and the actual number of electrons required for the reduction of ceftazidime are both calculated using the Ilkovic-Heyrovsky equation. The data show that ceftazidime requires five electrons for the reduction reaction to occur. The method has been successfully used to get ceftazidime on the market.Keywords: Ceftazidime, DPP, Analysis.

Combined Surface-Enhanced Raman and Infrared Absorption Spectroscopies for Streamlined Chemical Detection of Polycyclic Aromatic Hydrocarbon-Derived Compounds.

Polycyclic aromatic hydrocarbons (PAHs) constitute a class of universally prevalent carcinogenic environmental contaminants. It is increasingly recognized, however, that PAHs derivatized with oxygen, sulfur, or nitrogen functional groups are frequently more dangerous than their unfunctionalized counterparts. This much larger family of chemicals─polycyclic aromatic compounds─PACs─is far less well characterized than PAHs. Using surface-enhanced Raman and IR Absorption spectroscopies (SERS + SEIRA) combined on a single substrate, along with density functional theoretical (DFT) calculations, we show that direct chemical detection and identification of PACs at sub-parts-per-billion concentration can be achieved. Focusing our studies on 9,10-anthraquinone, 5,12-tetracenequinone, 9-nitroanthracene, and 1-nitropyrene as model PAC contaminants, detection is made possible by incorporating a hydroxy-functionalized self-assembled monolayer that facilitates hydrogen bonding between analytes and the SERS + SEIRA substrate. 5,12-Tetracenequinone was detected at 0.3 ppb, and the limit of detection was determined to be 0.1 ppb using SEIRA alone. This approach is straightforwardly extendable to other families of analytes and will ultimately facilitate fieldable chemical detection of these dangerous yet largely overlooked environmental contaminants.

OneGene PGT: comprehensive preimplantation genetic testing method utilizing next-generation sequencing.

Preimplantation genetic testing for monogenic disorders (PGT-M) allows early diagnosis in embryos conceived in vitro. PGT-M helps to prevent known genetic disorders in affected families and ensures that pathogenic variants in the male or female partner are not passed on to offspring. The trend in genetic testing of embryos is to provide a comprehensive platform that enables robust and reliable testing for the causal pathogenic variant(s), as well as chromosomal abnormalities that commonly occur in embryos. In this study, we describe PGT protocol that allows direct mutation testing, haplotyping, and aneuploidy screening. Described PGT protocol called OneGene PGT allows direct mutation testing, haplotyping, and aneuploidy screening using next-generation sequencing (NGS). Whole genome amplification product is combined with multiplex PCR used for SNP enrichment. Dedicated bioinformatic tool enables mapping, genotype calling, and haplotyping of informative SNP markers. A commercial software was used for aneuploidy calling. OneGenePGT has been implemented for seven of the most common monogenic disorders, representing approximately 30% of all PGT-M indications at our IVF centre. The technique has been thoroughly validated, focusing on direct pathogenic variant testing, haplotype identification, and chromosome abnormality detection. Validation results show full concordance with Sanger sequencing and karyomapping, which were used as reference methods. OneGene PGT is a comprehensive, robust, and cost-effective method that can be established for any gene of interest. The technique is particularly suitable for common monogenic diseases, which can be performed based on a universal laboratory protocol without the need for set-up or pre-testing.

ANCA: artificial nucleic acid circuit with argonaute protein for one-step isothermal detection of antibiotic-resistant bacteria

Endonucleases have recently widely used in molecular diagnostics. Here, we report a strategy to exploit the properties of Argonaute (Ago) proteins for molecular diagnostics by introducing an artificial nucleic acid circuit with Ago protein (ANCA) method. The ANCA is designed to perform a continuous autocatalytic reaction through cross-catalytic cleavage of the Ago protein, enabling one-step, amplification-free, and isothermal DNA detection. Using the ANCA method, carbapenemase-producing Klebsiella pneumoniae (CPKP) are successfully detected without DNA extraction and amplification steps. In addition, we demonstrate the detection of carbapenem-resistant bacteria in human urine and blood samples using the method. We also demonstrate the direct identification of CPKP swabbed from surfaces using the ANCA method in conjunction with a three-dimensional nanopillar structure. Finally, the ANCA method is applied to detect CPKP in rectal swab specimens from infected patients, achieving sensitivity and specificity of 100% and 100%, respectively. The developed method can contribute to simple, rapid and accurate diagnosis of CPKP, which can help prevent nosocomial infections.

A deep learning-based mobile app system for visual identification of tomato plant disease

<span lang="EN-US">Tomato is one of many horticulture crops in Indonesia which plays a vital role in supplying public food needs. However, tomato is a very susceptible plant to pests and diseases caused by bacteria and fungus. The infected diseases should be isolated as soon as it was detected. Therefore, developing a reliable and fast system is essential for controlling tomato pests and diseases. The deep learning-based application can help to speed up the identification of tomato disease as it can perform direct identification from the image. In this research, EfficientNetB0 was implemented to perform multi-class tomato plant disease classification. The model was then deployed to an android-based application using machine learning (ML) kit library. The proposed system obtained satisfactory results, reaching an average accuracy of 91.4%.</span>

SBioSITe enables sensitive identification of the cell surface proteome through direct enrichment of biotinylated peptides

BackgroundCell surface proteins perform critical functions related to immune response, signal transduction, cell–cell interactions, and cell migration. Expression of specific cell surface proteins can determine cell-type identity, and can be altered in diseases including infections, cancer and genetic disorders. Identification of the cell surface proteome remains a challenge despite several enrichment methods exploiting their biochemical and biophysical properties.MethodsHere, we report a novel method for enrichment of proteins localized to cell surface. We developed this new approach designated surface Biotinylation Site Identification Technology (sBioSITe) by adapting our previously published method for direct identification of biotinylated peptides. In this strategy, the primary amine groups of lysines on proteins on the surface of live cells are first labeled with biotin, and subsequently, biotinylated peptides are enriched by anti-biotin antibodies and analyzed by liquid chromatography–tandem mass spectrometry (LC–MS/MS).ResultsBy direct detection of biotinylated lysines from PC-3, a prostate cancer cell line, using sBioSITe, we identified 5851 peptides biotinylated on the cell surface that were derived from 1409 proteins. Of these proteins, 533 were previously shown or predicted to be localized to the cell surface or secreted extracellularly. Several of the identified cell surface markers have known associations with prostate cancer and metastasis including CD59, 4F2 cell-surface antigen heavy chain (SLC3A2) and adhesion G protein-coupled receptor E5 (CD97). Importantly, we identified several biotinylated peptides derived from plectin and nucleolin, both of which are not annotated in surface proteome databases but have been shown to have aberrant surface localization in certain cancers highlighting the utility of this method.ConclusionsDetection of biotinylation sites on cell surface proteins using sBioSITe provides a reliable method for identifying cell surface proteins. This strategy complements existing methods for detection of cell surface expressed proteins especially in discovery-based proteomics approaches.

570. Impact of a Blood Culture Direct Identification Procedure on Time to Identification for Gram-Negative Organisms and Antimicrobial Management in Bloodstream Infections

Abstract Background Multiplex polymerase chain reaction (PCR) and microarray diagnostic methods for rapid identification (ID) in Gram-negative bloodstream infections (GNBSI) remain unavailable in many healthcare facilities. Use of other methods such as matrix-associated laser desorption/ionization time-of-flight (MALDI-TOF) along with rapid sample preparation from positive blood cultures, may decrease time to ID and targeted antimicrobial therapy in BSI. This study compares time to ID and final susceptibilities of Gram-negative bacteria (GNB) in positive blood cultures using a rapid MALDI-TOF direct ID process versus conventional culture methods, as well as impact on antimicrobial therapy in GNBSI. Methods This retrospective cohort included patients ≥18 years of age who had a positive blood culture with a GNB from January 1 through December 31, 2022, at a hospital serviced by the microbiology lab at Banner University Medical Center Phoenix (conventional ID) or Banner University Medical Center Tucson (direct ID). Direct ID consisted of using MALDI-TOF for immediate ID of a centrifuged sample from a GNB-positive blood culture bottle. The primary outcome was time to GNB ID between the two groups. Secondary outcomes included time from positive blood culture to susceptibility reporting, definitive antibiotic regimen, and hospital discharge. Statistical analysis performed with Wilcoxon Rank-Sum testing for continuous data, and Chi square testing for nominal data. Results A total of 254 patients were evaluated, with 100 included in each group. Median time to bacterial ID in the direct group vs. conventional group was 6.1 hr vs 29.2 hr (P< 0.0001). No differences in secondary outcomes, including times to final susceptibility (54.0 hr vs 60.9 hr, P=0.73), definitive antibiotic regimen (49.5 hr vs 44.9 hr, P=0.42), and hospital discharge (132.5 hr vs. 124.4 hr, P=0.85) were noted, though this study may have been unable to detect differences in such outcomes due to variance in organism resistance patterns and clinical practice between facilities. Conclusion Direct MALDI-TOF ID significantly decreases time to organism identification in GNBSI compared with conventional methods. Utilization of direct ID plus antimicrobial stewardship interventions in GNBSI is an area of opportunity. Disclosures All Authors: No reported disclosures

PROBLEM-BASED LEARNING MODEL IN ACHIEVEMENT OF COMPETENCE OF NURSING STUDENTS DURING THE COVID-19 PANDEMIC

Background: A new policy has occurred in the world of education due to the impact of the COVID-19 pandemic, which has changed learning that must come to a class or a building or campus, to become independent learning, including nursing students. In this case, they are still required to have abilities by existing competency standards, including cognitive, affective, and psychomotor abilities that can be achieved by applying case-based learning and project-based learning models.
 Objectives: Find out the problem-based learning model in the competency achievement of nursing students during the COVID-19 pandemic.
 Methods: The research method used is analytic observational with a case-control approach. The variables in this research are teaching methodology as an independent variable and competency achievement as a dependent variable. The research was conducted for 5 months at the Diploma Nursing Study Program, Faculty of Nursing, Universitas Jember. The data collection technique in this study was by using an instrument in the form of Nursing Clinical Exercise (NCEx). The research respondents were Diploma Nursing Study Program Students with a total of 101 treatment groups with the criteria of having passed in 2022.
 Results: The research results show that learning models based on Case case-based learning and project-based learning are very important to develop in the classroom, laboratory, and clinical learning where students need real conditions about real cases that require direct identification and recognition. The use of PjBL may lead to improved competency achievement among nursing students. This could be reflected in higher scores on competency assessments, better clinical performance, and a deeper understanding of nursing concepts. Students also really need to be in real contact with nursing cases, especially the conditions of the COVID-19 pandemic which is a challenge for educators and students in the world of health.
 Conclusion: The problem-based learning method is very helpful for students in meeting the competency targets for graduates of the third diploma in nursing.

TOFIMS mass spectrometry-based immunopeptidomics refines tumor antigen identification

T cell recognition of human leukocyte antigen (HLA)-presented tumor-associated peptides is central for cancer immune surveillance. Mass spectrometry (MS)-based immunopeptidomics represents the only unbiased method for the direct identification and characterization of naturally presented tumor-associated peptides, a key prerequisite for the development of T cell-based immunotherapies. This study reports on the implementation of ion mobility separation-based time-of-flight (TOFIMS) MS for next-generation immunopeptidomics, enabling high-speed and sensitive detection of HLA-presented peptides. Applying TOFIMS-based immunopeptidomics, a novel extensive benignTOFIMS dataset was generated from 94 primary benign samples of solid tissue and hematological origin, which enabled the expansion of benign reference immunopeptidome databases with > 150,000 HLA-presented peptides, the refinement of previously described tumor antigens, as well as the identification of frequently presented self antigens and not yet described tumor antigens comprising low abundant mutation-derived neoepitopes that might serve as targets for future cancer immunotherapy development.

Characterization and antifungal susceptibility of <i>Trichophyton mentagrophytes</i> isolated from a goat presented with severe dermatophytosis in Zaria, Nigeria

Dermatophytosis is a contagious skin disease affecting domestic and wild animals with considerable zoonotic significance. The disease is caused by fungi known as dermatophytes in the genera Trichophyton, Microsporum and Epidermophyton. A goat was observed with circumscribed alopecic, highly inflammatory, thickly crusted skin lesions on the head region, especially around the eyes. Skin scraping, including hair pullouts, was aseptically obtained and processed for direct examination, isolation and microscopic identification of etiologic agent and supplemented with urease test. The isolate was tested for its susceptibility to fluconazole, griseofulvin, itraconazol and ketoconazole. Direct examination revealed hyaline, septate hyphae in skin scales and chains of endothrix spores within hair shafts, suggesting Trichophyton infection. Colonies on Sabouraud’s dextrose agar were white, flat and granular. Microscopic examination of the isolate revealed many oval micro-conidia arranged in grapelike clusters with multi-septate, club- shaped, thin, and smooth-walled macroconidia typical of Trichophyton mentagrophytes. The isolate was urease-positive and sensitive to itraconazole and ketoconazole but resistant to fluconazole and griseofulvin. It was concluded that T. mentagrophytes was the cause of the severe skin lesions in the goat. The need to perform antifungal susceptibility testing on dermatophytes isolated from clinical specimens for effective management of dermatophytosis was emphasized.

Rapid identification of erosion thinning and scaling thickening of inner wall of circular tube based on inverse heat conduction problem method

Due to the erosion of fluid and the deposition of fouling in pipes, the internal defects of pipelines are widespread and seriously threaten the safety of industrial production. In this paper, an indirect inversion model based on modified one-dimensional correction method (MODCM) is proposed to identify the erosion thinning and fouling deposition of the inner wall of a two-dimensional circular tube. By constructing the relationship between the equivalent thermal conductivity and the geometric parameters of defect, the inversion of defects is transformed into the inversion of the equivalent thermal conductivity, which overcomes the difficulty of re-gridding caused by the change of the geometric domain during the iterative process, and effectively improves the calculation efficiency. In order to explore the validity and timeliness of the constructed models, the numerical experiments are carried out. The influence of measurement errors, thermal conductivity of pipe and thermal conductivity of fouling on the identification results are systematically analyzed. The research results show that the thermal conductivities of pipes and fouling have little effect on the inversion results, and the inversion accuracy decreases with the increase of measurement errors. When the measurement error is σ = 0.5 ℃, the identification error remains about 0.2 %, which shows that the method has good robustness. In addition, compared with the typical direct identification models of Levenberg-Marquardt method (LMM) and conjugate gradient method (CGM), the proposed indirect inversion model is superior in computational efficiency and tracking ability of discontinuous boundaries.

Concerning the presumptive identification of Candida kefyr on Uriselect™4 agar.

Non-albicans Candida species, such as Candida kefyr, are emerging pathogens. Chromogenic media are highly useful for the diagnosis of urinary tract infections (UTIs). The aim was to describe the behavior of this specie on a non-specific chromogenic medium. A retrospective study of cases of candiduria detected in the Microbiology laboratory of the Virgen de las Nieves Hospital in Granada (Spain) between 2016 and 2021 (N=2,130). Urine samples were quantitatively seeded on non-selective UriSelect™4 chromogenic agar. Between 2016 and 2021, C. kefyr was the seventh most frequent Candida species responsible for candiduria in our setting (n=15). The macroscopic appearance of C. kefyr colonies, punctiform and bluish, allowed the direct identification of these microorganisms. This study provides the first description of the specific behavior of C. kefyr on UriSelect™4 agar, which differentiates it from other Candida species based on its enzymatic characteristics.

Investigation of the influence of the loading arrangement on the measured mode-I fracture resistance

This paper investigates the influence of the loading arrangement of double cantilever beam (DCB) test on the computed fracture resistance parameters of a structural adhesive. Aluminium joints were tested on three conventional loading arrangements from the BS ISO 25217:2009. We have found that the compliance of different loading arrangements can lead to significant differences in the fracture resistance computed using the cross-head displacement of the tensile-testing machine, even after considering the take-up of play and machine-compliance effects. In contrast, using the digital image correlation to measure the load-line displacement results in fracture resistance that is essentially independent of the loading arrangement. This finding was confirmed using three different data-reduction schemes, which yielded almost identical values of fracture resistance (less than 1% difference). Furthermore, direct identification of the traction-separation law at the crack tip was performed using Savitzky–Golay filter to compute the derivative of the J integral with regard to normal separation. Again, no significant influence of the loading arrangement was found since identified values of the separation at the peak traction and maximum separation are in excellent agreement. The identified maximum separation can be used as a threshold value of the relative deflection of the DCB arms to automatically determine the crack-tip position.

Evaluation of Immulex S. pneumoniae Omni test for the direct detection of S. pneumoniae from positive blood cultures

Rapid and early identification of Streptococcus pneumoniae from positive blood cultures is crucial for the management of patients with bloodstream infections (BSI). Many identification systems in microbiology laboratories have difficulty differentiating S. pneumoniae from other closely related species in the Streptococcus mitis group. To overcome this limitation, we developed a rapid workflow in our laboratory combining direct MALDI-TOF MS identification with the Immulex S. pneumoniae Omni test (SSI Diagnostica, Denmark) for rapid detection of S. pneumoniae directly from positive blood cultures. The workflow was evaluated using 51 Streptococcus isolates. Compared to conventional biochemical testing, our new workflow demonstrates 100 % specificity and sensitivity for the detection and differentiation of S. pneumoniae from other closely related species. Our new workflow is accurate, cost-effective, and can easily be implemented in microbiology laboratories that already perform direct MALDI-TOF identification from positive blood cultures to improve the management of patients with invasive pneumococcal disease. ImportanceInvasive pneumococcal disease remains a major public health problem worldwide. Reducing the time to identify Streptococcus pneumoniae in positive blood cultures allows patients to be treated sooner with more targeted and effective antibiotics. We evaluated a two-step protocol where positive blood cultures are first tested directly by MALDI-TOF MS and any samples containing Streptococcus species are tested by Immulex S. pneumoniae Omni test to both detect and differentiate S. pneumoniae from other closely related Streptococcus species. Our study results showed 100 % sensitivity and specificity, and a much faster turn-around time than conventional methods.

Betatron Acceleration of Suprathermal Electrons within a Small-scale Flux Rope in the Solar Wind

A growing body of evidence from observations, theories, and simulations indicates that particles can be effectively accelerated in solar wind regions filled with dynamic small-scale flux ropes (FRs). The main acceleration mechanisms identified in simulations include parallel electric field acceleration, first-order Fermi acceleration, and generalized betatron acceleration in contracting or merging small-scale FRs. However, direct identification of these acceleration mechanisms from in situ measurements remains a challenge. Here we present a distinct event of local betatron acceleration within a contracting small-scale FR in the solar wind, due to a local compression. In this event, the lower-energy halo electrons were effectively accelerated through the betatron mechanism, whereas the higher-energy suprathermal electrons predominated by the superhalo component were almost not energized. The halo electron energization processes via the betatron mechanism are reproduced using an analytical model. Further examination of small-scale FRs in the vicinity of the heliospheric current sheet over the period 1995–2020 indicates that in situ signatures of the betatron acceleration process are essentially elusive.

Hierarchical Fluid Interface Enables Spatiotemporal Regulation of Ligand Distribution to Increase Kinetics and Thermodynamics of Interfacial Binding Reaction

AbstractIn nature, regulation of the spatiotemporal distribution of interfacial receptors and ligands leads to optimum binding kinetics and thermodynamics of receptor–ligand binding reactions within interfaces. Inspired by this, we report a hierarchical fluid interface (HieFluidFace) to regulate the spatiotemporal distribution of interfacial ligands to increase the rate and thermodynamic favorability of interfacial binding reactions. Each aptamer‐functionalized gold nanoparticle, termed spherical aptamer (SAPT), is anchored on a supported lipid bilayer without fluidity, like an “island”, and is surrounded by many fluorescent aptamers (FAPTs) with free fluidity, like “rafts”. Such ligand “island‐rafts” model provides a large reactive cross‐section for rapid binding to cellular receptors. The synergistic multivalency of SAPTs and FAPTs improves interfacial affinity for tight capture. Moreover, FAPTs accumulate at binding sites to bind to cellular receptors with clustered fluorescence to “lighten” cells for direct identification. Thus, HieFluidFace in a microfluidic chip achieves high‐performance capture and identification of circulating tumor cells from clinical samples, providing a new paradigm to optimize the kinetics and thermodynamics of interfacial binding reactions.

Hierarchical Fluid Interface Enables Spatiotemporal Regulation of Ligand Distribution to Increase Kinetics and Thermodynamics of Interfacial Binding Reaction.

In nature, regulation of the spatiotemporal distribution of interfacial receptors and ligands leads to optimum binding kinetics and thermodynamics of receptor-ligand binding reactions within interfaces. Inspired by this, we report a hierarchical fluid interface (HieFluidFace) to regulate the spatiotemporal distribution of interfacial ligands to increase the rate and thermodynamic favorability of interfacial binding reactions. Each aptamer-functionalized gold nanoparticle, termed spherical aptamer (SAPT), is anchored on a supported lipid bilayer without fluidity, like an "island", and is surrounded by many fluorescent aptamers (FAPTs) with free fluidity, like "rafts". Such ligand "island-rafts" model provides a large reactive cross-section for rapid binding to cellular receptors. The synergistic multivalency of SAPTs and FAPTs improves interfacial affinity for tight capture. Moreover, FAPTs accumulate at binding sites to bind to cellular receptors with clustered fluorescence to "lighten" cells for direct identification. Thus, HieFluidFace in a microfluidic chip achieves high-performance capture and identification of circulating tumor cells from clinical samples, providing a new paradigm to optimize the kinetics and thermodynamics of interfacial binding reactions.

Evaluation of a Modified Protocol for the SepsiPrep Kit for Direct Identification and Antimicrobial Susceptibility Testing From Positive Blood Culture Using BACTEC Plus and BacT/Alert Blood Culture Bottles

Evaluation of a Modified Protocol for the SepsiPrep Kit for Direct Identification and Antimicrobial Susceptibility Testing From Positive Blood Culture Using BACTEC Plus and BacT/Alert Blood Culture Bottles