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Abstract Increasing access to water quality tests in low-income communities is a crucial strategy toward achieving global water equality. Recent studies in the Water Sanitation and Hygiene (WASH) sector underscore the importance of addressing practical concerns in water testing, such as robustness and results communication. In response, we present the WaterScope testing kit; an open-source, validated platform for drinking water quality assessment. It modernises the testing process with the inclusion of a unique cartridge/slider mechanism, machine-learning-enhanced classification and full digitalisation of results. WaterScope’s equivalency to conventional methods for quantifying E. coli is established through extensive validation experiments in both laboratory and field environments. This versatile platform provides potential to expand its applications to test other bacteria, perform colorimetric assays, and analyse clinical samples such as blood/urine samples. We anticipate that the system’s ease-of-use, portability, affordability, robustness, and digital nature will accelerate progress toward global water equality.

Trichloroethylene (TCE) is a prevalent groundwater contaminant detected worldwide, and microbes are sensitive indicators and initial responders to these chemical contaminants causing disturbances to their ecosystem. In this study, microbes isolated from San Marcos River sediment were screened for their TCE degradation potential. Among the twelve isolates (SAN1-12), five isolates demonstrated TCE degradation within 5 days at 25 °C and 40 mg/L of TCE concentration in the following order: SAN8 (87.56%), SAN1 (77.31%), SAN2 (76.58%), SAN3 (49.20%), and SAN7 (3.36%). On increasing the TCE concentration to 80 mg/L, the degradation efficiency of these isolates declined, although SAN8 remained the prominent TCE degrader with 75.67% degradation. The prominent TCE-degrading isolates were identified as Aeromonas sp. SAN1, Bacillus sp. SAN2, Gordonia sp. SAN3, and Bacillus proteolyticus SAN8 using 16S rRNA sequencing. The TCE degradation and cell biomass of Bacillus proteolyticus SAN8 were significantly improved when the incubation temperature was increased from 25 °C to 30 °C. However, both slightly acidic and alkaline pH levels, as well as higher TCE concentrations, lowered the efficacy of TCE degradation. Nevertheless, these conditions led to an increase in bacterial cell biomass.

Surface-enhanced Raman scattering (SERS) substrates based on chemical mechanism (CM) have received widespread attentions for the stable and repeatable signal output due to their excellent chemical stability, uniform molecular adsorption and controllable molecular orientation. However, it remains huge challenges to achieve the optimal SERS signal for diverse molecules with different band structures on the same substrate. Herein, we demonstrate a graphene oxide (GO) energy band regulation strategy through ferroelectric polarization to facilitate the charge transfer process for improving SERS activity. The Fermi level (Ef) of GO can be flexibly manipulated by adjusting the ferroelectric polarization direction or the temperature of the ferroelectric substrate. Experimentally, kelvin probe force microscopy (KPFM) is employed to quantitatively analyze the Ef of GO. Theoretically, the density functional theory calculations are also performed to verify the proposed modulation mechanism. Consequently, the SERS response of probe molecules with different band structures (R6G, CV, MB, PNTP) can be improved through polarization direction or temperature changes without the necessity to redesign the SERS substrate. This work provides a novel insight into the SERS substrate design based on CM and is expected to be applied to other two-dimensional materials.

Surface‐enhanced Raman spectroscopy (SERS) has emerged as a distinctive fingerprinting technique, offering a broad spectrum of applications encompassing environmental monitoring, chemical detection, and biomolecular analysis. Electrically modulated SERS (E‐SERS) stands as a technique which leverages an electric field to finely control the Raman signal based on the foundational principles of SERS. Through the manipulation of the physicochemical attributes of a metal or 2D material substrate, E‐SERS brings about an enhancement of the SERS signal. This enhancement occurs through a charge transfer process and modulation of the plasma resonance. This article showcases recent strides in the domain of E‐SERS, encompassing advancements such as the integration of paired integrated electrodes, piezoelectric materials, and pyroelectric materials in the construction of substrates. An exhaustive analysis of the mechanism underpinning the enhancement of the Raman signal is undertaken, alongside an exploration of the prominent attributes characterizing diverse methods for conditioning Raman signals. Elucidations are provided on the significance of employed electric fields in the augmentation of SERS and their manifold applications in drug identification, chemical detection, and catalysis. In summation, a delineation of challenges and perspectives inherent to E‐SERS substrates is presented, delineating a path for prospective comprehensive exploration within this auspicious realm of research.

Abstract Online detection of insulation defects the decomposition products of SF6 plays a key role in ensuring the safe operation of the gas‐insulated switchgear (GIS) equipment. The pristine TiO2 (1 0 1) modified by Ni cluster (1–3 Ni atoms) is used as a new gas‐sensing material to study its gas‐sensing characteristics to the characteristic decomposition products of SF6: SO2, SOF2, and SO2F2. Through density functional theory (DFT) calculation, we found that the modification of Ni clusters significantly improved the conductivity of pristine TiO2 (1 0 1) and the gas sensitivity of SF6 decomposition products. More importantly, the change of conductivity after gas adsorption lays a theoretical foundation for identifying the type and concentration of SF6 characteristic decomposition products and further judging the type of defects in GIS.

Abstract Background Work-related neck pain (WRNP) is a leading cause of disability and absenteeism. Patients with neck pain often have neck muscle tenderness and decreased cervical mobility, which are sometimes combined with psychosocial issues, such as pain catastrophising, thereby reducing their work ability. Whilst multidisciplinary treatments, including pharmacological interventions, manual therapy and specific neck exercises, have produced positive outcomes, effective personalised treatment modalities are still needed. Furthermore, manual therapies using the hands can bring fatigue to therapist. Occiflex is a computerised device that can provide personalised segmental joint mobilisation based on symptoms and injury of the patient and then provide a medium range of joint activities to improve range of cervical motion. This study aims to compare the effect of computerised mobilisation performed with Occiflex with that of traditional manual therapy on WRNP. Methods We will conduct a prospective randomised controlled trial including 150 patients with WRNP. These patients will be randomly assigned to one of three groups: (i) home exercise (TE), (ii) home exercise plus Occiflex therapy and (iii) home exercise plus manual therapy delivered by a physical therapist. Ten treatment sessions will be performed in four weeks. During the trial, these patients will receive only the assigned treatment and the standard patient education and will be asked not to use any analgesics unless strictly necessary. Assessments by trained evaluators will occur at baseline, week 4 and week 12. The primary outcome measures will include visual analogue scale (VAS) for pain and neck disability index (NDI) at each time point. Secondary outcome measures will include cervical range of motion (CROM), pressure pain threshold (PPT), global perceived effect (GPE) and sick leave. Group by time differences will be analysed using linear mixed models with repeated measures. Discussion This protocol describes the methods for a randomised controlled trial to compare the effectiveness of computerised versus manual mobilisation techniques in treating WRNP. The results will provide an alternative method (Occiflex) that is possibly effective for treating neck pain whilst minimising the manual work done by therapists. Trial registration The study protocol was retrospectively registered at http://www.chictr.org.cn (registration number: ChiCTR2100053076) on November 10, 2021.

BackgroundInsulin resistance (IR) is one of the common pathological manifestations of metabolic-related diseases, and the prevalence of relevant diseases is high. Acupuncture is beneficial to IR patients, but the central mechanism underlying this treatment remains unclear. This study provides mechanistic insights into how electroacupuncture (EA) improves IR through the response of Pro-opiomelanocortin (POMC) neurons to adiponectin (Adipo).MethodsGlucose tolerance tests (GTT), Insulin tolerance tests (ITT) and fasting blood glucose (FBG) were detected by glucometer. Serum insulin, Adipo and skeletal muscle adiponectin receptor 1 (AdipoR1) protein levels were examined by ELISA. Homeostasis model assessment estimated insulin resistance (HOMA-IR) was calculated using the following formula: HOMA-IR = fasting insulin (FINS) (mU/L) × FBG (mmol/L)/22.5. The expression levels of AdipoR1 and Adipo mRNA in skeletal muscle were detected by real-time PCR quantification. The co-marking of c-Fos/AdipoR1 and POMC neurons were investigated using immunofluorescence. Spontaneous excitatory postsynaptic currents (sEPSCs) of POMC neurons and the response of POMC neurons to Adipo were detected via electrophysiology.ResultsEA significantly ameliorated HFD-induced impairment of GTT, ITT, FBG, and HOMA-IR which was correlated with recovery of the expression level of AdipoR1 and Adipo in skeletal muscle. The improved response of POMC neurons to Adipo in the hypothalamus may be a key factor in correcting abnormal glucose tolerance and improving IR.ConclusionThis study demonstrates that EA can ameliorate HFD-induced impaired glucose tolerance through improved response of POMC neurons to Adipo in the hypothalamus, providing insight into the central mechanism of improving IR through EA.

Targeted protein degradation (TPD) facilitates the selective elimination of unwanted and pathological cellular cargoes via the proteasome or the lysosome, ranging from proteins to organelles and pathogens, both within and outside the cell. Currently, there are several in vitro and in vivo protocols that assess the degradative potency of a given degrader towards a myriad of targets, most notably soluble, monomeric oncoproteins. However, there is a clear deficiency of methodologies to assess the degradative potency of heterobifunctional chimeric degraders, especially those in the autophagy space, against pathological, mutant tau species, such as detergent-insoluble oligomers and high-molecular aggregates. The protocol below describes both in vitro and in vivo biochemical assays to induce tau aggregation, as well as to qualitatively and quantitatively measure the degradative potency of a given degrader towards said aggregates, with specific applications of the AUTOTAC (AUTOphagy-TArgeting Chimera) platform provided as an example. A well-defined set of methodologies to assess TPD-mediated degradation of pathological tau species will help expand the scope of the TPD technology to neurodegeneration and other proteinopathies, in both the lab and the clinic.Graphical abstractOverview of assays observing elimination of tauP301L aggregates with AUTOTAC. (A) Description of the biological working mechanism of heterobifunctional chimeric AUTOTAC degraders. (B) Schematic illustration of assays described in this paper.

Mesoporous silica SBA-15 is shown to be a very efficient alternative to phase transfer catalyst salts for two-phase nucleophilic substitutions. The two-phase reaction can efficiently take place in the absence of PTCs. The high catalytic activity and reaction rates can be attributed to the amphiphilic and negatively charged surface of SBA-15 as well as the rapid ingress of the reactants and egress of the products.

Abstract: During the analyses of ore and rock samples by Hydride Generation-Atomic Fluorescence Spectrometry (HG-AFS), many residues were formed in the tubes in which the hydride was generated, transport channelled and atomized. If a certain amount of the residues accumulat, they can distinctively affect the detection sensitivity of Se and Te. Many coexisting ingredients in the samples have a large influence on the detection of Se and Te by HG-AFS. In this article, to avoid interference from these ingredients, the series of standard solutions prepared with highly pure material were used. The standard solutions were tested with used tubes and cleaned ones. Through comparison of the data of the standard solutions, it was demonstrated that the residues in the instrument affected the detection of Se and Te by making the detection sensibility lower and the linear correlation coefficient smaller. The residues were analyzed with Atomic Fluorescence Spectrometry, Atomic Absorption Spectroscopy and Inductively Coupled Plasma-Atomic Emission Spectrometry. On the basis of the analytical results of the residues, Ti, Cu, As, Sb and Bi have great effect on the detection sensitivity and the linear correlation coefficient of Se and Te. These elements are a part of the coexisting interferences mentioned in literatures. When the tubes were cleaned, the measured quality was remarkably improved with higher sensitivity, and the linear correlation coefficient was more than 0.9995. According to the data obtained in this study, indications are that the analysis of residue components in the tubes is one of the effective methods to control the interference of HG-AFS.

Absorbance spectroscopy is routinely used to monitor the concentrations of nucleic acids and proteins within solutions and to assess changes in their structure caused by interaction with chemicals or other biomolecules. Biological samples used for such analyses are manipulated and stored in small microcentrifuge tubes (microtubes) composed of polypropylene plus several plastic additives. Here we demonstrate that normal handling of laboratory microtubes causes leaching of light-absorbing chemicals into biological samples that interfere with spectrophotometric measurements. The leached chromophores absorbed UV light strongly at 220 and 260 nm, which are the wavelengths normally used to detect and quantitate proteins and DNA. Some common laboratory techniques, including sonication and PCR, were particularly effective inducers of leaching. The magnitude of the increase in absorbance was dependent upon both exposure time and heat history, with greatest induction after tubes were warmed to temperatures at or above 37°C. Mass spectrometry revealed that aqueous solutions stored in plastic microtubes accumulate a complex mixture of leached chemicals with molecular masses of 200–1400 Da. Leaching was ubiquitous among commercially available brands of microtubes, indicating a persistent source of error in biomolecule detection and concentration measurements.

Foreign object detection is an important part of quality control of electricity meters. An automatic detection device is developed based on acoustic identification. In order to suppress background noise interference, we design a novel sound separation algorithm to separate the mixed sound signals to obtain the target source signal produced by foreign objects. Firstly, the improved principal-component-analysis-based multi-layered nonnegative matrix factorization (PMNMF) is used to separate sound signals. Secondly, the SVM is used to classify and identify sound signals. A suppot vector machine (SVM) as the classifier is used to compare the PMNMF algorithm with the basic NMF algorithm. The results indicate that the sound data pre-processed with the improved NMF algorithm results in a significantly higher identification rate up to about 95%.

Bacterial enoyl-acyl carrier protein reductase (FabI) is a promising novel antibacterial target. We isolated a new class of FabI inhibitor from Penicillium chrysogenum, which produces various antibiotics, the mechanisms of some of them are unknown. The isolated FabI inhibitor was determined to be meleagrin by mass spectroscopy and nuclear magnetic resonance spectral analyses, and its more active and inactive derivatives were chemically prepared. Consistent with their selective inhibition of Staphylococcus aureus FabI, meleagrin and its more active derivatives directly bound to S. aureus FabI in a fluorescence quenching assay, inhibited intracellular fatty acid biosynthesis and growth of S. aureus, and increased the minimum inhibitory concentration for fabI-overexpressing S. aureus. The compounds that were not effective against the FabK isoform, however, inhibited the growth of Streptococcus pneumoniae that contained only the FabK isoform. Additionally no resistant mutant to the compounds was obtained. Importantly, fabK-overexpressing Escherichia coli was not resistant to these compounds, but was resistant to triclosan. These results demonstrate that the compounds inhibited another target in addition to FabI. Thus, meleagrin is a new class of FabI inhibitor with at least one additional mode of action that could have potential for treating multidrug-resistant bacteria.