bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comprehensive correlation analysis of electromechanical behavior in high-stretchable carbon nanotube/polymer composites
Authors: Jin Seong-Won , Go Myeong-Seok , Lee Youngu , Ryu Seunghwa , Lim Jae Hyuk 
Published: June 2024

Abstract
In this study, a comprehensive correlation analysis of highly stretchable carbon nanotube (CNT)/polymer composites was conducted to predict the change in electrical conductivities in response to uniaxial deformation. To this end, the representative volume elements (RVEs) were generated by randomly distributing CNTs in a polymer matrix using a Monte Carlo simulation algorithm. The effective electrical conductivity was then calculated through a network model. Under uniaxial tensile strain, where the length of CNTs was maintained constant and their configuration kept straight, CNT translation and rotation were considered along with the effects of tensile strain and shrinkage, incorporating Poisson’s ratio. The RVE configuration was updated to account for changes in the network under these conditions. To achieve a strong correlation between the simulation and test results from the previously published works, numerous trade-off studies have been conducted on the RVE size, geometric periodicity, the length of CNT fibers, the mixing ratio of CNT fibers of CNT/polymer composites, and tensile strain. From the results it can be seen that excellent correlations can be only achieved with careful control of the aforementioned parameters.
A novel method for high-sensitivity detection of SARS-CoV-2 using dual double-quenched fluorescence probes
Authors: Zhu Chunsen , Fang Hao , Ma Houshi , Xue Jinbing , Li Zeqin , Wu Xi , Luo Gangyin 
Published: June 2024

ABSTRACT
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected many people around the world; fast and accurate detection of the virus can help control the spread of the virus. Reverse transcription-polymerase chain reaction (RT-PCR) is the gold standard method for SARS-CoV-2 detection. In this study, we improved the RT-PCR by proposing a novel method using dual double-quenched fluorescence probes. We used the improved probes to detect the plasmid DNA and RNA reference materials of SARS-CoV-2, respectively. The results show that, the background fluorescence intensity reduced by 50%, the fluorescence increment increased to 2.8 folds, and the Ct value significantly reduced by 3 or more, indicating that the detection sensitivity increased at least 8 times. In addition, we demonstrated that the improved probes have well performance in detecting SARS-CoV-2, with the minimum concentration of 6.2 copies/µL. This study will help biological companies develop better products for SARS-CoV-2 and other clinical pathogen infection.
Can developmental plasticity shape sexual competition and promote reproductive isolation?
Authors: Hubakk Kristin , Wylde Zachariah , Bonduriansky Russell 
Published: June 2024

Abstract
Environmental factors, such as dietary nutrients, can shape the expression of developmentally plastic sexual traits in many species. However, while there has been extensive research into the developmental plasticity of sexual traits at the individual level, the broader consequences of this variation at the population scale remain poorly understood. Here, we asked whether plastic responses to the developmental environment can shape sexual competition and initiate reproductive isolation between populations. We reared neriid flies, Telostylinus angusticollis, on nutrient-rich and nutrient-poor larval diets, generating adult flies that differed in body size and secondary sexual trait expression. We then investigated sexual competition in experimental populations from each developmental environment and tested for reproductive isolation between flies from mismatched environments. We found that, compared with poor-diet populations, rich-diet populations exhibited more frequent and escalated male–male combat and more frequent mating and mate-guarding. However, we found no evidence that sexual selection was affected by the developmental environment. Mismatched female–male pairs tended to take longer to mate and rich-diet females often rejected poor-diet males, but mismatched pairs were not less likely to mate within 1 h or produce viable offspring. Our findings suggest that developmental plasticity could generate dramatic differences in sexual competition between populations and could contribute to reproductive isolation.
Effects of Rock Type and Food Availability on Bioerosion by the Purple Sea Urchin, Strongylocentrotus purpuratus
Authors: Troha Lukas U , Narvaez Carla A , Russell Michael P 
Published: June 2024

Synopsis
Purple sea urchins (Strongylocentrotus purpuratus) profoundly impact nearshore rocky coasts through their feeding habits. Their intense grazing sculpts substrates through bioerosion using their teeth and spines and controls the alternative stable state dynamic between kelp bed and urchin barrens. These states have contrasting food availability for sea urchins, with abundant food in kelp beds and scarce food in barren grounds. However, the relationship between food availability and bioerosion is unknown. We predicted that when kelp is available, it would ameliorate the action of teeth on the substrate. Our 11-week long, 2 × 2 factorial experiment, crossed community state (kelp present vs absent) and rock type (sandstone vs mudstone). We also quantified the contribution of spine abrasion to bioerosion on the two rock types. The bioerosion rates did not differ between treatments with and without kelp. Although there was no significant difference in net bioerosion between the rock types, there was a large difference between the proportion of bioerosion from teeth vs spine abrasion. Approximately a third of the sandstone bioerosion was from spines whereas less than 2% of mudstone bioerosion could be attributed to spines. As anticipated, growth of sea urchins fed kelp ad-libitum was higher than food-limited sea urchins. Surprisingly, sea urchins on mudstone (which has a higher organic component) grew faster than sea urchins on sandstone. Although bioerosion rates may not differ on a per-urchin basis between community states, the sea urchin population densities between kelp beds and urchin barrens likely causes a difference in net bioerosion between these communities. Our results point to the importance of lithology on the mechanics of sea urchin bioerosion. Differences in texture, grain size, and hardness of rock substrates undoubtedly contribute to bioerosion rates and dynamics.
Exact and numerical solutions of a free boundary problem with a reciprocal growth law
Authors: McDonald N R , Harris Samuel J 
Published: June 2024

Abstract
A two-dimensional free boundary problem is formulated in which the normal velocity of the boundary is proportional to the inverse of the gradient of a harmonic function $T$. The field $T$ is defined in a simply connected region which includes the point at infinity where it has a logarithmic singularity. The growth problem in which the boundary expands outwards is formulated both in terms of the Schwarz function of the boundary and a Polubarinova–Galin equation for the conformal map of the region from the exterior of the unit disk. An expanding free boundary is shown to be stable and explicit solutions for growing ellipses and a class of polynomial lemniscates are derived. Numerical solution of the Polubarinova–Galin equation is used to compute the evolution of the boundary having other initial shapes.
Antibiotic resistance in Mycobacterium tuberculosis alters tolerance to cell wall-targeting inhibitors
Authors: Jowsey William J , Cook Gregory M , McNeil Matthew B 
Published: June 2024

Abstract

Background
A limited ability to eliminate drug-resistant strains of Mycobacterium tuberculosis is a major contributor to the morbidity of TB. Complicating this problem, little is known about how drug resistance-conferring mutations alter the ability of M. tuberculosis to tolerate antibiotic killing. Here, we investigated if drug-resistant strains of M. tuberculosis have an altered ability to tolerate killing by cell wall-targeting inhibitors.

Methods
Bacterial killing and MIC assays were used to test for antibiotic tolerance and synergy against a panel of drug-resistant M. tuberculosis strains.

Results
Our results demonstrate that vancomycin and thioacetazone exhibit increased killing of diverse drug-resistant strains. Mutations in mmaA4 and mmpL3 increased vancomycin killing, which was consistent with vancomycin synergizing with thioacetazone and MmpL3-targeting inhibitors. In contrast, mutations in the mce1 operon conferred tolerance to vancomycin.

Conclusions
Overall, this work demonstrates how drug-resistant strains experience perturbations in cell-wall production that alters their tolerance to killing by cell wall-targeting inhibitors.
A Comparative Analysis of Two Commonly Used FDA-Approved Immunoassays for Fentanyl Detection
Authors: Lam K H Brian , Menlyadiev Marlen , Buggs Vincent , Parnprome Suttida , Pesce Amadeo , Suhandynata Raymond T , Fitzgerald Robert L , Song Lu , Metushi Imir G 
Published: June 2024

Abstract

Background
Given the opioid epidemic, fentanyl screening in urine has become increasingly important. Immunoassays remain the most common screening methodology due to the high throughput and ease of integration into automated chemistry systems. The fentanyl ARK II from Ark Diagnostics is a widely used immunoassay, while a novel fentanyl assay called FEN2 by Lin-Zhi has become available on the Roche platform. Here, we evaluate and compare their performance.

Methods
Four hundred and thirty-four urine samples were analyzed for fentanyl across the Lin-Zhi FEN2 and ARK II assays on the Cobas c502 platform. Samples were analyzed immediately upon request for drug of abuse screening or frozen for subsequent analysis. For confirmation testing, a liquid chromatography–tandem mass spectrometry (LC-MS/MS) method with a limit of detection of 1 ng/mL for fentanyl/norfentanyl was used. Any sample with either fentanyl or norfentanyl above the LC-MS/MS cutoff was deemed positive.

Results
The ARK II had 11 false negatives and 7 false positives, while the Lin-Zhi FEN2 had 12 false negatives and 2 false positives. This resulted in ARK II having a sensitivity and specificity of 90.4% and 97.8% respectively, while Lin-Zhi FEN2 had a sensitivity and specificity of 89.5% and 99.4%.

Conclusions
Both the ARK II and Lin-Zhi FEN2 immunoassays detected fentanyl well. Overall, the Lin-Zhi assay had slightly better specificity than ARK II, in our data set. While some discrepant results were observed between the 2 immunoassay systems, most occurred near the immunoassay detection cutoffs.
Role and significance of virus–bacteria interactions in disease progression
Authors: Pokhrel Vatsala , Kuntal Bhusan K , Mande Sharmila S 
Published: June 2024

Abstract
Understanding disease pathogenesis caused by bacteria/virus, from the perspective of individual pathogen has provided meaningful insights. However, as viral and bacterial counterparts might inhabit the same infection site, it becomes crucial to consider their interactions and contributions in disease onset and progression. The objective of the review is to highlight the importance of considering both viral and bacterial agents during the course of coinfection. The review provides a unique perspective on the general theme of virus−bacteria interactions, which either lead to colocalized infections that are restricted to one anatomical niche, or systemic infections that have a systemic effect on the human host. The sequence, nature, and underlying mechanisms of certain virus−bacteria interactions have been elaborated with relevant examples from literature. It also attempts to address the various applied aspects, including diagnostic and therapeutic strategies for individual infections as well as virus–bacteria coinfections. The review aims to aid researchers in comprehending the intricate interplay between virus and bacteria in disease progression, thereby enhancing understanding of current methodologies and empowering the development of novel health care strategies to tackle coinfections.
Development and Performance Evaluation of a New Test Kit for Quantifying the Degree of DNA Fragmentation
Authors: Toyota Kazuki , Noma Satoshi , Kikuchi Yosuke , Satou Megumi , Tanaka Tomoki , Takiya Toshiyuki , Kokutani Ryota , Minegishi Yasutaka , Futo Satoshi , Takabatake Reona , Kitta Kazumi , Mano Junichi 
Published: June 2024

Abstract

Background
PCR-based genetic testing of agricultural products and foods is widely used for detecting various analytical targets such as genetically modified organisms and food allergens. However, it is difficult to obtain accurate genetic testing results from processed foods because DNA is fragmented by heat and pressure during food processing. Thus, we previously developed an analytical method to quantitatively evaluate the degree of DNA fragmentation for the purpose of QC of genetic testing for processed foods.

Objective
Our previous analytical method requires four PCR primer sets, resulting in high reagent costs and heavy analytical workloads. Therefore, we attempted to develop an easy-to-use test kit for quantifying the degree of DNA fragmentation and to evaluate its analytical performance.

Methods
To simplify the analysis procedure, we used only two primer sets. In addition, no-fragmentation control templates were prepared to obtain stable measurement results. The precision of the simplified analysis was evaluated through blind tests between laboratories.

Results
It was confirmed that plant species and extracted DNA concentrations had little effect on analysis with the newly developed test kit. In addition, the analytical values indicating the degree of DNA fragmentation exhibited small variability between laboratories.

Conclusion
We confirmed the high practicality of the developed test kit. Because DNA fragmentation in cells is a universal phenomenon, we anticipate that the test kit will be used not only for QC of genetic testing but also for food testing, medical diagnostics, and other applications in a range of fields.

Highlights
The newly developed test kit enables quantitative evaluation of the degree of DNA fragmentation in a simple manner.
Understanding the Complexity of Microbiology Method Validation to Meet State-Specific Requirements for Cannabis
Authors: Bird Patrick , Mills John , Johnson Ronald , McIntyre Maria , Valadez Azucena 
Published: June 2024

Abstract

Background
Federal legislation still prohibits the cultivation, sale, and consumption of cultivars of delta 9-tetrahydrocannabinol cannabis (&gt;0.3%); however, as of November 2022, 39 states have legalized cannabis and cannabis derived products for medicinal consumption and 21 states have legalized for adult-use consumption. This state-by-state approach has produced a patch work of regulations that multi-state operators (MSOs) must learn to navigate. Furthermore, cannabis laboratories often lack the space and skill needed to perform method validations, adding another layer of complexity. While these barriers exist, it is paramount for MSOs to demonstrate the fitness of purpose of their methods.

Objective
This review presents the complexity that an MSO navigated in developing microbiology method validation study designs for two proprietary real-time PCR (RT-PCR) assays to meet four state (California, Florida, Michigan, and Oklahoma) testing requirements. The testing in each state was conducted in addition to certification of the assays through the AOAC Performance Tested MethodSM (PTM) program.

Methods
Matrix studies were conducted targeting three analytes (Aspergillus spp., Salmonella spp., and Shiga toxin-producing Escherichia coli) as directed by the state regulatory authorities. For California, inclusivity and exclusivity studies were performed. The number of contamination levels, test portion replicates, and total target organisms evaluated varied by state. Culture confirmation was not performed outside of the AOAC PTM studies.

Results
Data from each study was collected, summarized, and provided to the state regulatory agencies. Review of the data consisted of identifying discrepant results and verification of controls. After review, each assay was certified for use in the respective state.

Conclusion
Requirements from each of the states demonstrate the complexities MSOs face and emphasize the need for a more standardized approach to streamline acceptance of alternative methods.

Highlights
While varying state regulations can be complex, validation studies performed for the candidate methods have led to adoption across 31 states.
Horizontal sodium density variations for laser guide star tip-tilt measurements
Authors: Holdorf Erin , Martínez-Rey Noelia 
Published: June 2024

ABSTRACT
Adaptive optics, particularly with laser guide stars, has revolutionized ground-based astronomy. However, one known limitation is the requirement of a natural guide star to retrieve tip-tilt information. This is the limiting factor in the overall achievable sky coverage with adaptive optics systems as natural guide stars are not available for all science targets. There have been numerous different techniques proposed to overcome this limitation; however, many are restricted by current technology. This work investigates the use of density perturbations in the sodium layer to retrieve the tip-tilt information. In this work, we identify atmospheric gravity waves as a mechanism that could cause perturbations in the sodium layer density. Archival hydroxyl airglow data was analysed to assess whether the density perturbations caused by atmospheric gravity waves are on the correct scales and have enough contrast to be used for laser guide star tip-tilt retrieval. This data showed a median contrast of 1.9 per cent for a laser guide star with a full width half-maximum of 25 arcsec. Then to determine if these perturbations would be visible with a laser guide star at a high enough signal-to-noise ratio, the Mathematica package LGSBloch was utilized. The CaNaPy laser guide star R&D facility was chosen to model as it has a state-of-the-art 70 W sodium laser. Promising results were found when modelling this method with the CaNaPy facility as a framework. This demonstrates that if these same perturbations were present in the sodium layer, sodium density variations are a potential mechanism to retrieve tip-tilt using laser guide stars.
A radio quasi-periodic oscillation in the blazar PKS J2156−0037
Authors: Mao Lisheng , Zhang Xuemei 
Published: June 2024

ABSTRACT
The detection of quasi-periodic oscillations (QPOs) in blazar light curves is crucial for understanding their nature and fundamental physical processes. PKS J2156−0037 (z = 0.495), a blazar monitored by the Owens Valley Radio Observatory (OVRO) 40-m radio telescope, is the subject of this study. We searched for the presence of QPOs in the publicly available 15 GHz light curve of PKS J2156−0037, spanning 2008 January to 2020 January. We employed four well-established methods (the Jurkevich method, the generalized Lomb–Scargle periodogram, the weighted wavelet Z-transform, and the redfit method) that offer complementary strengths for robust periodicity detection. A consistent and statistically significant QPO signal was detected with a periodicity of around 611 d (at least 4.26σ local significance) and a global significance exceeding 99.83 per cent (or 2.92σ) based on Monte Carlo simulations with 105 simulated light curves (assuming underlying red-noise processes). This is the first reported detection of such a variability feature in this object. The possible physical mechanisms responsible for radio QPOs in blazars are discussed briefly.
Combined therapeutic strategy based on blocking the deleterious effects of AGEs for accelerating diabetic wound healing
Authors: Yang Yang , Huang Siwen , Ma Qing , Li Ning , Li Runchu , Wang Yongjun , Liu Hongzhuo 
Published: June 2024

Abstract
Diabetic foot ulcer is a serious complication of diabetes. Excessive accumulation of advanced glycation end products (AGEs) is one of the critical pathogenic factors in postponing diabetic wound healing. The main pathogenic mechanisms of AGEs include inducing cellular dysfunction, prolonging inflammatory response, increasing oxidative stress and reducing endogenous nitric oxide (NO) production. Combination therapy of blocking the deleterious effects of AGEs and supplementing exogenous NO is hypothesized to promote diabetic wound healing. Here, we presented nanoparticles/hydrogel composite dressings to co-delivery rosiglitazone and S-nitroso glutathione into the wound bed. The designed co-delivery system augmented the survival of fibroblasts, reduced oxidative stress levels, reversed the change of mitochondrial membrane potential and decreased the proinflammatory cytokine expression. Local sustained release of therapeutic agents significantly improved the wound healing of diabetic rats including increasing the wound closure rate, alleviating inflammation, promoting collagen fiber production and angiogenesis. Our finding indicated this local deliver strategy aimed at inhibiting the toxic effects of AGEs has great clinical potential for diabetic wound treatment.
Estimating the Prevalence of Using Suspected Counterfeit Medications in the General Population
Authors: Jewell Jennifer S. , Bemis Elizabeth A. , Black Joshua C. 
Published: June 2024

Introduction
Counterfeit medications, sometimes referred to as “fake” or falsified drugs or pills, are drugs that are illicitly manufactured but designed to look like legitimate pharmaceuticals. Counterfeit medications are a growing public health concern. This study estimated the prevalence of self-reported use of suspected counterfeit medications by adults in the US and to assess what ingredients these individuals suspected were in the counterfeit medications.

Methods
This general population survey, drawn from an online panel, was administered across 2 waves in 2022 (15 April 3 June and 9 September 21 October) to 59,041 adults aged 18 and older. Statistical calibration weighting was used to calculate estimates representative of the national adult population.

Results
An estimated 1.8% (95% CI 1.7%–1.9%) of respondents, corresponding to approximately 4.6 million adults, suspected past 12-month use of counterfeit medications. Fentanyl was the most commonly suspected ingredient in the counterfeit product (16.1%, 95% CI 12.8%–19.3%). The next most prevalent response was “I don’t know” (15.0%, 95% CI 11.0%–18.9%) followed by methamphetamine (14.9%, 95% CI 11.4%–18.4%).

Conclusions
These data show the scale of the issue in relation to other well established drug use data points in the US. System-level methods, such as drug scanning software, should be implemented to reduce the likelihood that counterfeit drugs end up in the hands of individuals.