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Oxytetracycline (OTC) is a widely employed antibiotic in veterinary treatment and in the prevention of infections, potentially leaving residues in animal-derived food products, such as milk, that are consumed by humans. Given the detrimental effects of prolonged human exposure to antibiotics, it has become imperative to develop precise and sensitive methods for monitoring the presence of OTC in food. Herein, we describe the development and results of a preliminary label-free electrochemical aptasensor with antifouling properties designed to detect OTC in milk samples. The sensor was realized by modifying a gold screen-printed electrode with α-lipoic acid–NHS and an amine-terminated aptamer. Different electrochemical techniques were used to study the steps of the fabrication process and to quantify OTC in the presence of the Fe(CN)64−/Fe(CN)63− redox couple The detectable range of concentrations satisfy the maximum residue limits set by the European Union, with an limit of detection (LOD) of 14 ng/mL in phosphate buffer (BP) and 10 ng/mL in the milk matrix, and a dynamic range of up to 500 ng/mL This study is a steppingstone towards the implementation of a sensitive monitoring method for OTC in dairy products. [ABSTRACT FROM AUTHOR]

Electrochemical biosensors are valued for their sensitivity and selectivity in detecting biological molecules. Having the advantage of generating signals that can be directly or indirectly proportional to the concentration of the target analyte, these biosensors can achieve specificity by utilizing a specific biorecognition surface designed to recognize the target molecule. Electrochemical biosensors have garnered substantial attention, as they can be used to fabricate compact, cost-effective devices, making them promising candidates for point-of-care testing (POCT) devices. This study introduces a label-free electrochemical biosensor employing a gold screen-printed electrode (SPE) to detect lysophosphatidic acid (LPA), a potential early ovarian cancer biomarker. We employed the gelsolin–actin system, previously introduced by our group, in combination with fluorescence spectrometry, as a biorecognition element to detect LPA. By immobilizing a gelsolin–actin complex on an SPE, we were able to quantify changes in current intensity using cyclic voltammetry and differential pulse voltammetry, which was directly proportional to the LPA concentration in the solution. Our results demonstrate the high sensitivity of the developed biosensor for detecting LPA in goat serum, with a limit of detection (LOD) and a limit of quantification (LOQ) of 0.9 µM and 2.76 µM, respectively, highlighting its potential as a promising tool for early-stage diagnosis of ovarian cancer. [ABSTRACT FROM AUTHOR]

The overall 5-year survival rate of ovarian cancer (OC) is generally low as the disease is often diagnosed at an advanced stage of progression. To save lives, OC must be identified in its early stages when treatment is most effective. Early-stage OC causes the upregulation of lysophosphatidic acid (LPA), making the molecule a promising biomarker for early-stage detection. An LPA assay can additionally stage the disease since LPA levels increase with OC progression. This work presents two methods that demonstrate the prospective application for detecting LPA: the electromagnetic piezoelectric acoustic sensor (EMPAS) and a chemiluminescence-based iron oxide nanoparticle (IONP) approach. Both methods incorporate the protein complex gelsolin–actin, which enables testing for detection of the biomarker as the binding of LPA to the complex results in the separation of gelsolin from actin. The EMPAS was characterized with contact angle goniometry and atomic force microscopy, while gelsolin–actin-functionalized IONPs were characterized with transmission electron microscopy and Fourier transform infrared spectroscopy. In addition to characterization, LPA detection was demonstrated as a proof-of-concept in Milli-Q water, buffer, or human serum, highlighting various LPA assays that can be developed for the early-stage detection of OC. [ABSTRACT FROM AUTHOR]

Lysophosphatidic acid (LPA) is a promising biomarker candidate to screen for ovarian cancer (OC) and potentially stratify and treat patients according to disease stage. LPA is known to target the actin-binding protein gelsolin which is a key regulator of actin filament assembly. Previous studies have shown that the phosphate headgroup of LPA alone is inadequate to bind to the short chain of amino acids in gelsolin known as the PIP2-binding domain. Thus, the molecular-level detail of the mechanism of LPA binding is poorly understood. Here, we model LPA binding to the PIP2-binding domain of gelsolin in the gelsolin-actin complex through extensive ten-microsecond atomistic molecular dynamics (MD) simulations. We predict that LPA binding causes a local conformational rearrangement due to LPA interactions with both gelsolin and actin residues. These conformational changes are a result of the amphipathic nature of LPA, where the anionic phosphate, polar glycerol and ester groups, and lipophilic aliphatic tail mediate LPA binding via charged electrostatic, hydrogen bonding, and van der Waals interactions. The negatively-charged LPA headgroup binds to the PIP2-binding domain of gelsolin-actin while its hydrophobic tail is inserted into actin, creating a strong LPA-insertion pocket that weakens the gelsolin–actin interface. The computed structure, dynamics, and energetics of the ternary gelsolin–LPA–actin complex confirms that a quantitative OC assay is possible based on LPA-triggered actin release from the gelsolin-actin complex. [ABSTRACT FROM AUTHOR]

The restoration of soil organic matter (SOM, as measured by soil organic carbon (SOC)) within the world's agricultural soils is imperative to sustaining crop production and restoring other ecosystem services. We compiled long-term studies on the effect of management practices on SOC from Iowa, USA—an agricultural region with relatively high-quality soil data—to highlight constraints on detecting changes in SOC and inform research needed to improve SOC measurement and management. We found that strip-tillage and no-tillage increased SOC by 0.25–0.43 Mg C ha−1 yr−1 compared to losses of 0.24 to 0.46 Mg C ha−1 yr−1 with more intensive tillage methods. The conversion of cropland to perennial grassland increased SOC by 0.21–0.74 Mg C ha−1 yr−1. However, diversifying crop rotations with extended rotations, and supplementing synthetic fertilizer with animal manure, had highly variable and inconsistent effects on SOC. The improved prediction of changes in SOC requires: the use of methods that can identify and disentangle multiple sources of variability; looking beyond total SOC and toward systematic collection of data on more responsive and functionally relevant fractions; whole-profile SOC monitoring; monitoring SOC in long-term studies on the effect of multiple conservation practices used in combination; and deeper collaboration between field soil scientists and modelers. [ABSTRACT FROM AUTHOR]

A fundamental question of the 21st century centers around the role and place of humans in their environment. Given the great acceleration of consumptive practices engaged in the 20th century, humans stand on the brink of a 6th extinction event. In order to determine our place and role in our global environment, we need to reflect on where we are and what the future will be—we need to focus on the habits of our "co-inhabitation" of the planet. Given the positive and negative impacts of international and global activities, intercultural dialogues are necessary for the care of the ecology of the planet, and one of the most prescient dialogues is between Eastern and Western world views. While much comparative research has been conducted regarding the connection between American Transcendentalism and Chinese ancient philosophy, relatively little philosophical work has been conducted to demonstrate the connectivity between Henry David Thoreau and Taoism. Yet there are, in fact, profound similarities between the American naturalist and Chinese philosophy, in particular Taoism. This paper aimed to discover and manifest the connection and similarities between the philosophy of Thoreau and the ancient worldview of Taoism. Through this comparative study and intercultural dialogue, we seek to trace historical precedents and intercultural dialogue between American Transcendentalism and ancient Chinese philosophy in order to explore the groundwork for a new vision of environmental awareness in order to promote a better future with a community of co-inhabitants and emphasis on the well-being of all. [ABSTRACT FROM AUTHOR]

Contamination of food by pathogens can pose a serious risk to health. Therefore, monitoring for the presence of pathogens is critical to identify and regulate microbiological contamination of food. In this work, an aptasensor based on a thickness shear mode acoustic method (TSM) with dissipation monitoring was developed to detect and quantify Staphylococcus aureus directly in whole UHT cow's milk. The frequency variation and dissipation data demonstrated the correct immobilization of the components. The analysis of viscoelastic properties suggests that DNA aptamers bind to the surface in a non-dense manner, which favors the binding with bacteria. The aptasensor demonstrated high sensitivity and was able to detect S. aureus in milk with a 33 CFU/mL limit of detection. Analysis was successful in milk due to the sensor's antifouling properties, which is based on 3-dithiothreitol propanoic acid (DTTCOOH) antifouling thiol linker. Compared to bare and modified (dithiothreitol (DTT), 11-mercaptoundecanoic acid (MUA), and 1-undecanethiol (UDT)) quartz crystals, the sensitivity of the sensor's antifouling in milk improved by about 82–96%. The excellent sensitivity and ability to detect and quantify S. aureus in whole UHT cow's milk demonstrates that the system is applicable for rapid and efficient analysis of milk safety. [ABSTRACT FROM AUTHOR]

Domain experts prefer interactive and targeted control-point tone mapping operations (TMOs) to enhance underwater image quality and feature visibility; though this comes at the expense of time and training. In this paper, we provide end-users with a simpler and faster interactive tone-mapping approach. This is built upon Weibull Tone Mapping (WTM) theory; introduced in previous work as a preferred tool to describe and improve domain expert TMOs. We allow end-users to easily shape brightness distributions according to the Weibull distribution, using two parameter sliders which modify the distribution peak and spread. Our experiments showed that 10 domain experts found the two-slider Weibull manipulation sufficed to make a desired adjustment in >80% of images in a large dataset. For the remaining ∼20%, observers opted for a control-point TMO which can, broadly, encompass many global tone mapping algorithms. Importantly, 91% of these control-point TMOs can actually be visually well-approximated by our Weibull slider manipulation, despite users not identifying slider parameters themselves. Our work stresses the benefit of the Weibull distribution and significance of image purpose in underwater image enhancement. [ABSTRACT FROM AUTHOR]

Herbicide resistance is an important weed management issue. Glyphosate is the most dominant herbicide, which controls a broad spectrum of weeds, including grasses such as Lolium rigidum. Lolium rigidum is a major weed of winter crops in Australia that is developing glyphosate resistance in increasing numbers of populations and has been observed growing throughout summer in recent years. Three L. rigidum populations, one summer-emerging glyphosate-resistant (GR), one winter-emerging glyphosate-susceptible (GS), and one winter-emerging population with unknown resistance status (CC04), were analyzed for target-site resistance to glyphosate after confirming their resistance or susceptibility to glyphosate in a dose–response experiment. Population GR was obtained from plants that emerged in summer and contained plants that survived all rates of glyphosate applied (0 to 4560 g a.e. ha−1). It was found to be 6.1 and 4.4 times more resistant than population GS across two experiments. Population CC04 was identified as susceptible. Plants from each population were analyzed for the presence of target-site mutations in the conserved region of the EPSPS gene; however, no mutations were identified that could cause resistance, suggesting non-target-site resistance in population GR. The effectiveness of alternative herbicides was also analyzed for each population. Paraquat was the most effective herbicide, with 0% survival across all populations. The ACCase-inhibiting herbicide clethodim was also highly effective (0 to 8% survival across populations). Other ACCase-inhibiting herbicides, propaquizafop, haloxyfop, and pinoxaden, were effective at controlling the two susceptible populations, CC04 and GS (0 to 36% and 0 to 20% survival, respectively), but were only moderately effective for controlling GR (28 to 51% survival). Paraquat and clethodim may be alternative options for controlling GR populations of L. rigidum and could be effective for use in management programs to slow the development of GR populations. [ABSTRACT FROM AUTHOR]

Surfaces with antifouling properties are critical for optimizing biosensors to improve the selectivity and specificity of analyte detection in complex biological samples. This work describes the four-step synthesis of 3-dithiothreitol propanoic acid (DTTCOOH), a new antifouling thiol linker that (a) significantly reduces fouling of raw human serum samples and (b) binds amino receptors via its terminal carboxylic acid group. DTTCOOH was successfully functionalized on quartz crystal microbalance (QCM) discs and used to anchor penicillin-binding aptamers. Relative to bare and coated (11-mercaptoundecanoic acid (MUA) and 1-undecanethiol (UDT)) QCM crystals, DTTCOOH's antifouling improved by approximately 75–86%. Following aptamer/ethanolamine extension, the modified DTTCOOH layer reduced serum fouling by approximately 95–97% compared to bare and coated (MUA, UDT) crystals. QCM with dissipation (QCM-D) monitoring, contact goniometry, and cyclic voltammetry techniques were used to compare the DTTCOOH surfaces with quartz crystals functionalized with hydrophobic and hydrophilic molecules. [ABSTRACT FROM AUTHOR]

Indwelling urinary catheters are employed widely to relieve urinary retention in patients. A common side effect of the use of these catheters is the formation of urinary tract infections (UTIs), which can lead not only to severe medical complications, but even to death. A number of approaches have been used to attempt reduction in the rate of UTI development in catheterized patients, which include the application of antibiotics and modification of the device surface by coatings. Many of these coatings have not seen use on catheters in medical settings due to either the high cost of their implementation, their long-term stability, or their safety. In previous work, it has been established that the simple, stable, and easily applicable sterilization surface coating 2-(3-trichlorosilylpropyloxy)-ethyl hydroxide (MEG-OH) can be applied to polyurethane plastic, where it greatly reduces microbial fouling from a variety of species for a 1-day time period. In the present work, we establish that this coating is able to remain stable and provide a similarly large reduction in fouling against Escherichia coli and Staphylococcus aureus for time periods in an excess of 30 days. This non-specific coating functioned against both Gram-positive and Gram-negative bacteria, providing a log 1.1 to log 1.9 reduction, depending on the species and day. This stability and continued efficacy greatly suggest that MEG-OH may be capable of providing a solution to the UTI issue which occurs with urinary catheters. [ABSTRACT FROM AUTHOR]

This correction notice addresses errors in the affiliations and contact information of the authors of the publication titled "Long-Term Reduction of Bacterial Adhesion on Polyurethane by an Ultra-Thin Surface Modifier" in the journal Biomedicines. The correction includes updating the affiliation of Dalal Asker to include the Food Science and Technology Department at Alexandria University, as well as providing a permanent email address for her. Additionally, the misspelling of the address for Brian De La Franier and Michael Thompson has been corrected. The authors assure that these corrections do not impact the scientific conclusions of the publication. [Extracted from the article]

Al-Ce based alloys have gained recent interest and have proven to have excellent strength without heat treatment and high thermal stability. Challenges with the production of Al-Ce samples from elemental powders arise due to the elemental material before alloying being susceptible to rapid oxidation. The methodology for making superconductive wire, powder-in-tube, was used as a consolidate Al and Ce elemental powder, and Al-8 wt % Ce-10 wt % Mg composite powder into bulk nanostructured material. Powder samples are fabricated in an inert controlled atmosphere, then sealed in a tube to avoid oxidation of powders. Therefore, most of the powder is used without much loss. We used 316 stainless-steel tubes as a sheathing material. For Al-xCe wt % (x = 8 to 14) samples of elemental powder, liquid phase sintering was used and for Al-Ce-Mg powder solid-state sintering. Characterization of the bulk consolidated material after sintering, and before and after heat treatment, was made using optical and Scanning Electron Microscope imaging, Energy Dispersive Spectroscopy, Microhardness and Rockwell Hardness test. We demonstrated that microstructure stability in Al-Ce-based specimens can be retained after thermomechanical processing. Densification was achieved and oxidation of powder was avoided in most samples. In addition, we found that Fe and Ni in the sheathing material react with Al in the process, and Ce concentration modifies the reactivity the sheath. [ABSTRACT FROM AUTHOR]

Milk is a significant foodstuff around the world, being produced and consumed in large quantities. The safe consumption of milk requires that the liquid has an acceptably low level of microbial contamination and has not been subjected to spoiling. Bacterial safety limits in milk vary by country but are typically in the thousands per mL of sample. To rapidly determine if samples contain an unsafe level of bacteria, an aptamer-based sensor specific to Escherichia coli bacteria was developed. The sensor is based on an ultra-high frequency electromagnetic piezoelectric acoustic sensor device (EMPAS), with the aptamer being covalently bound to the sensor surface by the anti-fouling linker, MEG-Cl. The sensor is capable of the selective measurement of E. coli in PBS and in cow's milk samples down to limits of detection of 35 and 8 CFU/mL, respectively, which is well below the safe limits for commercial milk products. This sensing system shows great promise for the milk industry for the purpose of rapid verification of product safety. [ABSTRACT FROM AUTHOR]

Bacterial endotoxin, also known as lipopolysaccharide (LPS), plays a major role in the initiation of sepsis, a severe inflammatory condition. Removal of the toxin from blood is one accepted method of patient treatment. Polymyxin B (PMB)-modified columns have been employed successfully for this purpose via extra-corporeal blood-flow systems that incorporate a cartridge for toxin removal. Herein we demonstrate that PMB-modified glass beads are able to reduce the presence of LPS competitively with the equivalent fiber column used in a commercial cartridge. Analysis by gas chromatography-mass spectrometry and ELISA of released fatty acids from the toxin indicates that PMB does not physically capture or significantly remove LPS from the blood samples. In reality, interaction between the surface-bound PMB and the toxin may lead to disaggregation or monomerization of LPS aggregates. As aggregates are the bioactive form of LPS, it is possible that the monomerization of these entities may be the mechanism by which their toxicity is reduced. Moreover, this work indicates that LPS monomers are stabilized subsequent to disaggregation induced by PMB. [ABSTRACT FROM AUTHOR]

Detecting warfarin levels in the blood is of critical importance in anticoagulant therapy because it is imperative that the concentration of the drug is maintained within a specific range. In this paper, we present a proof-of-concept of a novel sensing device based on ion-selective electrode (ISE) technology for the direct detection of warfarin in blood samples without any sample pretreatment. We used tetradodecylammonium chloride (TDDA) as an ion-exchanger to fabricate an ion-selective membrane. The ISE we developed showed high sensitivity, with a limit of detection (LOD) of 1.25 × 10−7 M and 1.4 × 10−5 M for detecting warfarin in buffer and blood, respectively. The sensor also exhibited promising selectivity in identifying the presence of various ions including chloride and salicylate, the most abundant ions in blood with a calibration slope of 58.8 mV/dec. We envision combining the ISE with a microfluidic system and a simple potentiometer to produce a sensitive, selective, and portable point-of-care testing device for monitoring the level of warfarin in patients' blood during treatment. [ABSTRACT FROM AUTHOR]

Some plant species are able to acquire non-exchangeable forms of K, which improve K availability and cycling in cropping systems, and which may explain the lack of response to K. However, this would not be expected in soils dominated by kaolinite. The aim of this study was to assess non-exchangeable K (Kne) use by three selected plant species grown in a tropical Haplic Plinthosol with low exchangeable K (Ke). A greenhouse experiment was conducted with soybean (Glycine max L., Merr.), maize (Zea mays L.), and ruzigrass (Urochloa ruziziensis) with or without K fertilization for three growing cycles. The crop treatments were compared with a control without plants. In the absence of K fertilization, all the tested plants were able to use non-exchangeable K and non-exchangeable K contributed more than 80% of the K demand of the plants in the first growing cycle, even in this kaolinitic soil. In the first growing cycle, soybean and maize took up more non-exchangeable K than ruzigrass, concomitant with higher dry matter yields. Over the three crop cycles, as both biomass yield and K uptake decreased in the unfertilized systems, the dependence of plants on non-exchangeable K decreased. Unfertilized ruzigrass showed a strong ability to acquire non-exchangeable K from the soil. Over the course of three growing cycles, K application decreased the absolute uptake of non-exchangeable K as well as its fractional contribution to total K uptake by the crops. [ABSTRACT FROM AUTHOR]