Range Of Responses Research Articles

An ultrasensitive genosensor for detection of toxigenic and non-toxigenic Clostridioides difficile based on a conserved sequence in surface layer protein coding gene

Clostridioides difficile (C. difficile) is the most common agent of antibiotic-associated diarrhea, leading to intestinal infection through the secretion of two major toxins. Not all strains of this bacterium are toxigenic, but some of them cause infection via their accessory virulence factors, such as surface layer protein (SlpA). SlpA is conserved in both toxigenic and non-toxigenic strains of C. difficile. In the present work, an amplification-free electrochemical genosensor was designed for the detection of the slpA gene. A glassy carbon electrode coated with gold nanoparticle-reduced graphene oxide nanocomposite was used as the working electrode, and its surface was modified using a simple thiolated linear oligonucleotide as the bioreceptor. Moreover, the hexaferrocenium tri[hexa(isothiocyanato) iron(III)] trihydroxonium (HxFc) complex was used as an intercalator, and its redox signal was recorded using differential pulse voltammetry. Scan rate studies indicated a quasi-reversible adsorption-controlled process for the HxFc complex. This genosensor showed high sensitivity with a limit of detection of 0.2 fM, a linear response range of 0.46–1900 fM, and a satisfactory specificity toward the synthetic slpA target gene. Also, the genosensor indicated responses in the mentioned linear range toward the genome extracted from either toxigenic or non-toxigenic strains of C. difficile.

Complex genetic interaction between glucose sensor HXK1 and E3 SUMO ligase SIZ1 in regulating plant morphogenesis

ABSTRACT Sugar signaling forms the basis of metabolic activities crucial for an organism to perform essential life activities. In plants, sugars like glucose, mediate a wide range of physiological responses ranging from seed germination to cell senescence. This has led to the elucidation of cell signaling pathways involving glucose and its counterparts and the mechanism of how these sugars take control over major hormonal pathways such as auxin, ethylene, abscisic acid and cytokinin in Arabidopsis. Plants use HXK1(Hexokinase) as a glucose sensor to modulate changes in photosynthetic gene expression in response to high glucose levels. Other proteins such as SIZ1, a major SUMO E3 ligase have recently been implicated in controlling sugar responses via transcriptional and translational regulation of a wide array of sugar metabolic genes. Here, we show that these two genes work antagonistically and are epistatic in controlling responsiveness toward high glucose conditions.

The synergistic effect of POM-π interaction and solid phase amidation on the visible light photocatalytic of g–C3N4–based photocatalyst

Due to the unique ability of Keggin-type polyoxometalate (POM) to remain stable when accepting electrons to form mixed valence POM, organic-POM hybrid materials can complete multi-electron transfer while maintaining structural stability. The organic-POM hybrids photocatalysts prepared using organic materials and POM as raw materials have been developed to form new energy bands and crystal structures. This not only enhances their quantum efficiency and but also expands their visible light response range. Nevertheless, organic-POM hybrids, featuring organic amines as ligands, are prone to photoetching, impeding g-C3N4's progress in this area. In this paper, the amino group of g-C3N4 was converted into imide ring by solid phase amidation method, which overcame this obstacle and converted g-C3N4 into g-C3N4 based polyimide (CNPI) with enhanced photoelectric properties. XRD, IR spectrum, and XPS data indicate that CNPI is more tightly integrated with potassium phosphotungstate (KPW) than g-C3N4, demonstrating superior electron transport capabilities and potentiated POM-π interactions. In terms of photocatalytic efficacy, CNPI/KPW-30 % exhibits an impressive degradation rate constant of 0.5458 h−1 for imidacloprid, attributed to its compact microstructure and superior charge transfer capability. While maintaining good photocatalytic stability, the mineralization rate of CNPI/KPW-30 % to imidacloprid was 55.25 %. In addition, h+ and ·O2− were identified as active species through trapping agent experiments, and the degradation pathway was advanced by ESR technology analysis.

The marriage of perovskite nanocrystals with lanthanide‐doped upconversion nanoparticles for advanced optoelectronic applications

AbstractThe exceptional optoelectronic properties of lead halide perovskite nanocrystals (PeNCs) in the ultraviolet and visible spectral regions have positioned them as a promising class of semiconductor materials for diverse optoelectronic and photovoltaic applications. However, their limited response to near‐infrared (NIR) light due to the intrinsic bandgap (>1.5 eV) has hindered their applications in many advanced technologies. To circumvent this limitation, it is of fundamental significance to integrate PeNCs with lanthanide‐doped upconversion nanoparticles (UCNPs) that are capable of efficiently converting low‐energy NIR photons into high‐energy ultraviolet and visible photons. By leveraging the energy transfer from UCNPs to PeNCs, this synergistic combination can not only expand the NIR responsivity range of PeNCs but also introduce novel emission profiles to upconversion luminescence with multi‐dimensional tunability (e.g., wavelength, lifetime, and polarization) under low‐to‐medium power NIR irradiation, which breaks through the inherent restrictions of individual PeNCs and UCNPs and thereby opens up new opportunities for materials and device engineering. In this review, we focus on the latest advancements in the development of PeNCs‐UCNPs nanocomposites, with an emphasis on the controlled synthesis and optical properties design for advanced optoelectronic applications such as full‐spectrum solar cells, NIR photodetectors, and multilevel anticounterfeiting. Some future efforts and prospects toward this active research field are also envisioned.

A nano photocatalyst rGO/TiO2 modified by sol–gel‐irradiation and its degradation of deoxynivalenol in liquid products

SummaryThe rGO/TiO2 nanocomposite photocatalyst was synthesised using the sol–gel‐irradiation way to efficiently remove deoxynivalenol (DON) for the grains product's safety and quality. With the nanosize effect of irradiation, the photocatalyst has a smaller average grain size, preventing the recombination of electrons and holes. Moreover, based on UV–Vis DRS study, rGO/TiO2 could utilise visible light and have a broader response range to light. Furthermore, to the application, the photocatalyst rGO/TiO2 with 30 KGy irradiation dosage had an 80.32 ± 4.41% photocatalytic degradation rate of DON. Compared to the photocatalyst without irradiation, there was a 9.98% increase in the degradation rate. This result provided an excellent candidate photocatalyst for the removal of DON and also promoted the development of photocatalysis applications.

Analysis of huanglongbing-associated RNA-seq data reveals disturbances in biological processes within Citrus spp. triggered by Candidatus Liberibacter asiaticus infection

IntroductionHuanglongbing (HLB), a disease that’s ubiquitous worldwide, wreaks havoc on the citrus industry. The primary culprit of HLB is the gram-negative bacterium Candidatus Liberibacter asiaticus (CLas) that infects the phloem, but its damaging mechanism is yet to be fully understood.Methods and resultsIn this study, a multitude of tools including weighted correlation network analysis (WGCNA), protein-protein interaction (PPI) network analysis and gene expression profiling are employed to unravel the intricacies of its pathogenesis. The investigation pinpoints various central genes, such as the ethylene-responsive transcription factor 9 (ERF9) and thioredoxin reductase 1 (TrxR1), that are associated with CLas invasion and resultant disturbances in numerous biological operations. Additionally, the study uncovers a range of responses through the detection of differential expressed genes (DEGs) across different experiments. The discovery of core DEGs leads to the identification of pivotal genes such as the sieve element occlusion (SEO) and the wall-associated receptor kinase-like 15 (WAKL15). PPI network analysis highlights potential vital proteins, while GO and KEGG pathway enrichment analysis illustrate a significant impact on multiple defensive and metabolic pathways. Gene set enrichment analysis (GSEA) indicates significant alterations in biological processes such as leaf senescence and response to biotic stimuli.DiscussionThis all-encompassing approach extends valuable understanding into the pathogenesis of CLas, potentially aiding future research and therapeutic strategies for HLB.

Thermochromic Hydrogels with Adjustable Transition Behavior for Smart Windows.

With the fast economic development and accelerating urbanization, more and more skyscrapers made entirely of concrete and glass are being constructed. To keep a comfortable indoor environment, massive energy for air conditioning or heating appliances is consumed. A huge amount of heat (>30%) is gained or released through glass windows. Using smart windows with the capability to modulate light is an effective way to reduce building energy consumption. Thermochromic hydrogel is one of the potential smart window materials due to its excellent thermal response, high radiation-blocking efficiency, cost-effectiveness, biocompatibility, and good uniformity. In this work, polyhydroxypropyl acrylate (PHPA) hydrogels with controllable lower critical solution temperature (LCST) were prepared by photopolymerization. The transition temperature and transition rate under "static transition" conditions were investigated. Unlike "static" conditions in which the transition temperature was not affected by the initial and final temperature and heating/cooling ramp, the transition temperature varied with the rate of temperature change under dynamic conditions. The "dynamic" transition temperature of the PHPA hydrogel gradually increased with the increase of the heating rate. It was the result of the movement of the molecular chains lagging behind the temperature change when the temperature change was too fast. The results of the solar irradiation experiment by filling PHPA hydrogels into double glazing windows showed that the indoor temperature was about 15 °C lower than that of ordinary glass windows, indicating that it can significantly reduce the energy consumption of air conditioning. In addition, a wide range of adjustable transition temperatures and fast optical response make PHPA hydrogels potentially applicable to smart windows.

Land Use Sustainability: Assessment of the Dynamic Response of Typical Bedrock-Buried-Hill Earth Fissure Sites in the Su-Xi-Chang Area

Disaster prevention and the mitigation of earth fissures is a key issue in the sustainable development of urban land. Structures directly avoiding earth fissures are not conducive to the rational planning and efficient utilization of urban construction. The Su-Xi-Chang area, which consists of the cities of Suzhou, Wuxi, and Changzhou, surrounded by Taihu Lake, has developed bedrock buried-hill earth fissures that are rare in the rest of the country. Existing research results have identified the genesis mechanisms, distribution patterns, and developmental characteristics of this type of fissure. Not only does the slow-variable activity of earth fissures cause direct damage to surface and underground structures, but in addition, when an earthquake occurs, the presence of earth fissures may cause the seismic response of the site to be altered or even strengthened, leading to unknown damage or the possible destruction of structures near the fissures. However, no studies have been conducted to assess the dynamic effects of bedrock-buried-hill earth fissure sites. Therefore, in this research, based on six typical bedrock-buried-hill-type earth fissures in the Su-Xi-Chang area, and in order to accurately reveal the dynamic amplification effect law of the earth fissure sites, systematic spectral analyses and comparisons of the microtremor signals were carried out by using the linear analysis method (Direct Fourier Transform Analysis) and the nonlinear analysis method (Hilbert–Huang Transform). The results show that bedrock-buried-hill-type earth fissures have a significant amplification effect on the dynamic response of the site; the amplification effect of bedrock-buried-hill fissure sites follows the same attenuation pattern, and the furthest range of the dynamic response on the site is about 25 m, beyond which the original seismic fortification level can be maintained; the extreme value of the amplification factor of the two sides of this type of site, as derived from the Fourier and HHT methods, is about double, and the nearest earth fissure region should be considered to have a raised seismic fortification intensity of more than double the original. The Hilbert–Huang transform method has good applicability for processing microtremor data, and nonlinear signal analysis methods can be considered comprehensive for future microtremor signal processing.

To beckon or not to beckon: Testing a causal-evaluative modelling approach to moral judgment: A registered report

Moral judgments are increasingly being understood as showing context dependent variability. A growing literature has identified a range of specific contextual factors (e.g., emotions, intentions) that can influence moral judgments in predictable ways. Integrating these diverse influences into a unified approach to understanding moral judgments remains a challenge. Recent work by Railton (2017) attempted to address this with a causal-evaluative modelling approach to moral judgment. In support of this model Railton presents evidence from novel variations of classic trolley type dilemmas. We present results from a pre-registered pilot study that highlight a significant confound and demonstrate that it likely influenced Railton's results. Building on this, our registered report presents a replication-extension of Railton's study, using larger more diverse samples, and more rigorous methods and materials, specifically controlling for potential confounds. We found that participants' judgments in sacrificial dilemmas are influenced by both direct personal force, and by whether harm occurs as a means or as a side-effect of action. We also show the relationship between a range of individual difference variables and responses to sacrificial moral dilemmas. Our results provide novel insights into the factors that influence people's moral judgments, and contribute to ongoing theoretical debates in moral psychology.

Elasticity curves describe streamflow sensitivity to precipitation across the entire flow distribution

Abstract. Streamflow elasticity is the ratio of the expected percentage change in streamflow to a 1 % change in precipitation – a simple approximation of how responsive a river is to precipitation. Typically, streamflow elasticity is estimated for average annual streamflow; however, we propose a new concept in which streamflow elasticity is estimated for multiple percentiles across the full distribution of streamflow. This “elasticity curve” can then be used to develop a more complete depiction of how streamflow responds to climate. Representing elasticity as a curve which reflects the range of responses across the distribution of streamflow within a given time period, instead of as a single-point estimate, provides a novel lens through which we can interpret hydrological behaviour. As an example, we calculate elasticity curves for 805 catchments in the United States and then cluster them according to their shape. This results in three distinct elasticity curve types which characterize the streamflow–precipitation relationship at annual and seasonal timescales. Through this, we demonstrate that elasticity estimated from the central summary of streamflow, e.g. the annual median, does not provide a complete picture of streamflow sensitivity. Further, we show that elasticity curve shape, i.e. the response of different flow percentiles relative to one another in one catchment, can be interpreted separately from between-catchment variation in the average magnitude of streamflow change associated with a 1 % change in precipitation. Finally, we find that available water storage is likely the key control which determines curve shape.

Adsorption and gas sensitive behavior of Co2+ doped TiO2(101) crystal planes

Density functional theory (DFT) and Electrochemical Impedance Spectroscopy (EIS) were used to study the molecular adsorption behavior of the Co2+ doped TiO2(101) crystal plane, and the ethanol molecular gas sensitivity test was performed. Theoretical models indicate that doping leads to oxygen defects on the crystal plane and further chemisorption of two oxygen molecules, resulting in reduced electrical conductivity and improved oxygen storage capacity on the crystal plane. Ethanol molecules do not compete with N2, O2, and H2O molecules on doped crystal planes because of their different adsorption active sites, which means that the response time of gas-sensitive detection of ethanol molecules is short and is not interfered with the air molecules in the test environment. These results were confirmed by EIS and gas sensitivity experiments. The change of electrical conductivity after the adsorption of molecules on the crystal plane was confirmed by EIS. The enhanced oxygen storage capacity of the doped crystal plane was confirmed by the expansion of the linear response range of gas-sensitive detection from 20-100 ppm before doping to 20–1200 ppm. This provides a scientific basis for effectively shortening the gas-sensitive response time, increasing the concentration range, improving the oxygen-carrying capacity, and enhancing the catalytic and gas-sensitive properties of the material.

The single-cycle biphotons generated by SPDC in chirped QPM PPKTP crystal

In this paper, we have studied the process of monochromatic pump light in linearly chirped Periodically Poled [Formula: see text] (PPKTP) nonlinear crystal to generate single-cycle biphotons under Quasi-Phase-Matching (QPM) conditions through a Spontaneous Parametric Down-Conversion (SPDC). A detailed analysis of the phase mismatching function reveals that in PPKTP crystals, for the proper frequency range, the phase mismatching [Formula: see text] is stable and relatively close to 0 due to the relatively stable refractive index, and therefore has a good phase matching effect. Even when the chirp rate becomes small, it is able to produce single-cycle biphotons due to the near-perfect phase matching. Of course, as the chirp rate increases, the frequency response range becomes wider, the temporal width is narrower, and the number of cycles is smaller.

Subcellular dynamics of ethylene signaling drive plant plasticity to growth and stress: Spatiotemporal control of ethylene signaling in Arabidopsis.

Volatile compounds, such as nitric oxide and ethylene gas, play a vital role as signaling molecules in organisms. Ethylene is a plant hormone that regulates a wide range of plant growth, development, and responses to stress and is perceived by a family of ethylene receptors that localize in the endoplasmic reticulum. Constitutive Triple Response 1 (CTR1), a Raf-like protein kinase and a key negative regulator for ethylene responses, tethers to the ethylene receptors, but undergoes nuclear translocation upon activation of ethylene signaling. This ER-to-nucleus trafficking transforms CTR1 into a positive regulator for ethylene responses, significantly enhancing stress resilience to drought and salinity. The nuclear trafficking of CTR1 demonstrates that the spatiotemporal control of ethylene signaling is essential for stress adaptation. Understanding the mechanisms governing the spatiotemporal control of ethylene signaling elements is crucial for unraveling the system-level regulatory mechanisms that collectively fine-tune ethylene responses to optimize plant growth, development, and stress adaptation.

Nanostructures of Prussian blue supported on activated biochar for the development of a glucose biosensor

This work emphasizes the utilization of biochar, a renewable material, as an interesting platform for anchoring redox mediators and bioreceptors in the development of economic, environmentally friendly biosensors. In this context, Fe(III) ions were preconcentrated on highly functionalized activated biochar, allowing the stable synthesis of Prussian blue nanostructures with an average size of 58.3 nm. The determination of glucose was carried out by indirectly monitoring the hydrogen peroxide generated through the enzymatic reaction, followed by its subsequent redox reaction with reduced Prussian blue (also known as Prussian white) in a typical electrochemical-chemical mechanism. The EDC/NHS (1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride and N-Hydroxysuccinimide) pair was employed for the stable covalent immobilization of the enzyme on biochar. The biosensor demonstrated good enzyme-substrate affinity, as evidenced by the Michaelis-Menten apparent kinetic constant (4.16 mmol L−1), and analytical performance with a wide linear dynamic response range (0.05–5.0 mmol L−1), low limits of detection (0.94 μmol L−1) and quantification (3.13 μmol L−1). Additionally, reliable repeatability, reproducibility, stability, and selectivity were obtained for the detection of glucose in both real and spiked human saliva and blood serum samples.

Short-chain fatty acids: linking diet, the microbiome and immunity.

The short-chain fatty acids (SCFAs) butyrate, propionate and acetate are microbial metabolites and their availability in the gut and other organs is determined by environmental factors, such as diet and use of antibiotics, that shape the diversity and metabolism of themicrobiota. SCFAs regulate epithelial barrier function as well as mucosal and systemic immunity via evolutionary conserved processes that involve G protein-coupled receptor signalling or histone deacetylase activity. Indicatively, the anti-inflammatory role of butyrate is mediated through direct effects on the differentiation of intestinal epithelial cells, phagocytes, B cells and plasma cells, and regulatory and effector T cells. Intestinally derived SCFAs also directly and indirectly affect immunity at extra-intestinal sites, such as the liver, the lungs, the reproductive tract and the brain, and have been implicated in a range of disorders, including infections, intestinal inflammation, autoimmunity, food allergies, asthma and responses to cancer therapies. An ecological understanding of microbial communities and their interrelated metabolic states, as well as the engineering of butyrogenic bacteria may support SCFA-focused interventions for the prevention and treatment of immune-mediated diseases.

Linear Capacitive Pressure Sensor with Gradient Architecture through Laser Ablation on MWCNT/Ecoflex Film.

The practical application of flexible pressure sensors, including electronic skins, wearable devices, human-machine interaction, etc., has attracted widespread attention. However, the linear response range of pressure sensors remains an issue. Ecoflex, as a silicone rubber, is a common material for flexible pressure sensors. Herein, we have innovatively designed and fabricated a pressure sensor with a gradient micro-cone architecture generated by CO2 laser ablation of MWCNT/Ecoflex dielectric layer film. In cooperation with the gradient micro-cone architecture and a dielectric layer of MWCNT/Ecoflex with a variable high dielectric constant under pressure, the pressure sensor exhibits linearity (R2 = 0.990) within the pressure range of 0-60 kPa, boasting a sensitivity of 0.75 kPa-1. Secondly, the sensor exhibits a rapid response time of 95 ms, a recovery time of 129 ms, hysteresis of 6.6%, and stability over 500 cycles. Moreover, the sensor effectively exhibited comprehensive detection of physiological signals, airflow detection, and Morse code communication, thereby demonstrating the potential for various applications.

Design and implementation of a low-cost circuit for medium-speed flash analog to digital conversions

Despite the considerable advancements in analog-to-digital conversion (ADC) circuits, many papers neglect several crucial considerations: Firstly, it does not ensure that ADCs work well in the software or hardware. Secondly, it is not certain that ADCs have a wide range of amplitude responses for the input voltages to be convenient in many applications, especially in electronics, communications, computer vision, CubeSat circuits, and subsystems. Finally, many of these ADCs need to look at the suitability of the proposed circuit to the most extensive range of frequencies. In this paper, a design of a low-cost circuit is proposed for medium-speed flash ADCs. The proposed circuit is simulated based on a set of electronic components with specific values to achieve high stability operation for a wide range of frequencies and voltages, whether in software or hardware. This circuit is practically implemented and experimentally tested. The proposed design aims to achieve high efficiency in the sampling process over a range of amplitudes from 10 mV to 10 V. The proposed circuit operates at a bandwidth of frequencies from 0 Hz to greater than 10 kHz in the simulation and hardware implementation.

Thermally and magnetically responsive single layer bioinspired soft actuator with patterned structure obtained by direct ink writing

Multi-stimuli hydrogels are an important class of soft actuators, as they allow to expand the range of possible movements and responses by more closely mimicking living matter. Here we report the fabrication of thermally- and magnetically-responsive single layer hydrogel nanocomposite obtained by direct ink writing. Two types of ink, namely, thermosensitive based on poly(N-isopropylacrylamide (PNIPAM) and magnetically-sensitive based on magnetite, were distributed according to a certain pattern, forming a single-layer hydrogel sheet. Thermally-responsive inks due to “coil-to-globule” transformation of PNIPAM at temperatures above 32оC in aqueous solutions generate local internal stresses which lead to the transformation of the hydrogel’s shape. Magnetically sensitive ink allows to move the hydrogel in space by attracting it to a magnet. Ink formulations have been optimized to achieve thixotropic properties for the application of direct ink writing. The proposed hydrogel system represents a powerful platform for the development of biomedical soft robots because it consists of biocompatible components and operates in a temperature range close to the human body.

Ultra-Compact Optical Fiber Gas Sensor With High Sensitivity, Fast Response and Large Dynamic Range

Ultra-Compact Optical Fiber Gas Sensor With High Sensitivity, Fast Response and Large Dynamic Range

The book is just being written: The enduring journey of parents of children with emerging- ultrarare disorders.

Ultra rare disorders are being diagnosed at an unprecedented rate, due to genomic sequencing. These diagnoses are often a new gene association, for which little is known, and few share the diagnosis. For these diagnoses, we use the term emerging-ultrarare disorder (E-URD), defined as <100 diagnosed individuals. We contacted 20 parents of children diagnosed with an E-URD through the Duke University Research Sequencing Clinic. Seventeen completed semi-structured interviews exploring parental perspectives (7/17 had children in publications describing the phenotype; 4/17 had children in the first publication establishing a new disorder). Data were analyzed using a directed content approach informed by an empowerment framework. Parents reported a range of responses, including benefits of a diagnosis and challenges of facing the unknown, some described feeling lost and confused, while others expressed empowerment. Empowerment characteristics were hope for the future, positive emotions, engagement, and confidence/self-efficacy to connect with similar others, partner with healthcare providers, and seek new knowledge. We identified a subset of parents who proactively engaged researchers, supported research and publications, and created patient advocacy and support organizations to connect with and bolster similarly diagnosed families. Other parents reported challenges of low social support, low tolerance for uncertainty, limited knowledge about their child's disorder, as well as difficulty partnering with HCPs and connecting to an E-URD community. An overarching classification was developed to describe parental actions taken after an E-URD diagnosis: adjusting, managing, and pioneering. These classifications may help genetic counselors identify and facilitate positive steps with parents of a child with an E-URD.