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Broad-range PCR targeting 28S D1-D2 ribosomal DNA (rDNA) identifies numerous fungi but has limited sensitivity in clinical specimens. Ribosomal RNA (rRNA) vastly outnumbers rDNA, suggesting reverse transcription (RT)-PCR could improve detection. Among contrived samples, RT-PCR decreased 28S PCR cycle threshold values by 10--12 cycles and lowered the limit of detection > 2000-fold. Among 32 bronchoalveolar lavage specimens, RT-PCR detected 12/15 (80%) fungal PCR- or culture-positive specimens, versus 6/12 (50%) by 28S PCR, 9/12 (75%) by any fungal PCR, and 13/15 (87%) by culture. RT-PCR newly identified fungi in 4/17 (24%) PCR- and culture-negative specimens. RT substantially increased 28S PCR sensitivity overall. Lay summary Fungal infection remains difficult to diagnose in the laboratory. Here, we have shown that detecting ribosomal RNA and DNA, rather than only ribosomal DNA, in a broad range fungal assay results in a significant enhancement in the ability to detect and identify fungal pathogens in clinical samples. [ABSTRACT FROM AUTHOR]

It is crucial to develop highly energy-efficient and selective sensors for wide concentration range of H2S, a common toxic gas that widely exists in petrochemical industries. In this work, MoO2 nanospheres were rapidly synthesized by microwave-assisted solvothermal method, and were subsequently fabricated into H2S gas sensor. The MoO2 nanospheres-based sensor exhibited excellent response toward H2S with good linearity in a wide concentration range (10–240 ppm). Besides, this sensor presented low working temperature, good repeatability, and selectivity against CH4, H2, and CO. The outstanding sensing performance results from the reaction between H2S and abundant chemisorbed oxygen introduced by oxygen vacancies of MoO2. This result indicates that MoO2 nanosphere synthesized by microwave-assisted solvothermal method is a promising sensing material for H2S detection.

Equations for normalization of the limiting relative error of a device are presented. With the use of the criterion of the aggregate indicator of precision and range of a device, the advantage of normalization is demonstrated by means of an extended equation with three components of the limiting error: the additive component, multiplicative component, and hyperbolic component. Such normalization takes into account the hyperbolic nonlinearity of the characteristic of the conversion intrinsic to devices with parametric converters and many devices with a broad range of measurement possessing a linear-fractional (projective) measurement equation. Use of the extended equation for normalization of the limiting relative measurement error is suggested for devices with a broad range of measurement. [ABSTRACT FROM AUTHOR]

• This paper proposes a multi-level nano-micro sensing structure for pressure sensors. • A solution processable process is developed for low-cost and large-area fabrication. • Simultaneous improvement in multiple sensing performances is obtained. • The sensor demonstrates widespread application in biomonitoring and soft robots. Flexible pressure sensors are urgently needed in the fast-growing field of intelligent robots and human healthcare. However, most current pressure sensors can rarely achieve high sensitivity and dynamic behavior within a broad detection range, which greatly hinders their practical application. Herein, we develop a highly-sensitive, wide-range, and highly-dynamic MXene piezoresistive pressure sensor by constructing a multi-level nano-micro (MLNM) sensing structure. The unique structure was formed by combining the accordion-like layered nano-structures of MXene nanosheets and the abundant micro-protrusions transferred from sandpapers. It can dramatically increase the structure compressibility, the interlayer contact area, and thus resistance variations during compression, resulting in a synergistic enhancement in sensitivity, detection range, and dynamic performance. A fully solution-processable process based on sandpaper casting and oxygen plasma treatment enabled tough interface bonding was developed for low-cost and large-area fabrication. As a result, a high sensitivity of 3.94 kPa−1, a broad range of 0–117.5 kPa, rapid response and relaxation times of 70 ms and 84 ms, and long-term stability of > 7500 cyclic compression were obtained, which exhibited significant enhancement in comprehensive performance compared to previous reports. Successful monitoring of diverse human physiological signals and robot movements underscores the considerable practical utility of our MXene-based sensors. [ABSTRACT FROM AUTHOR]

Broad-range PCR has the potential to detect virtually any bacterial species via amplification and nucleotide sequencing of a DNA region common to all bacteria. We aimed to evaluate its usefulness and clinical relevance when applied to a wide variety of primary sterile materials. A prospective study including 1370 samples (75 heart valves, 151 joint tissue samples, 230 joint aspirates, 848 whole blood samples and 66 culture-negative cerebrospinal fluid samples) were studied by using a commercial PCR system for detecting 16S rDNA (Molzym). The PCR results were compared with culture and were considered to provide added diagnostic value only if the PCR approach revealed new pathogens that were missed by culture. The added value of PCR was evident in 173 of 555 PCR-positive samples (0.126; 0.109–0.144 (proportion from all tested samples; 95% confidence interval)), most frequently in examinations of heart valves (0.56; 0.448–0.672) and joint tissue samples (0.219; 0.153–0.284). In contrast, the lowest rate of PCR with added value was noted for blood samples, regardless of the patient cohort they had been drawn from (nononcologic patients from intensive care: 0.065; 0.043–0.087, haematooncologic children: 0.048; 0.027–0.070). Moreover, PCR missed up to 7.1% of blood culture findings (0.071; 0.048–0.095) regarded as clinically relevant, which was the second highest failure rate after joint tissue samples (0.099; 0.052–0.147). Broad-range PCR substantially increases detection rate of pathogens, especially from heart valves and joint samples. However, a concurrent risk of false-negative PCR results justifies the need for parallel culture. [ABSTRACT FROM AUTHOR]

This paper presents a ratiometric optical broad range pH sensor that comprises an optical fiber coated at one end with CdSe/ZnS quantum dots (QDs) and Oxazine 170 perchlorate (O170) embedded in ethyl cellulose (EC) matrix. The feasibility of coating an optical fiber with the sensing film to fabricate a ratiometric fiber optic broad range pH sensor is investigated. Using an LED with a central wavelength 405 nm as an excitation light source, the CdSe/ZnS QDs shows that the fluorescence intensity at 575 nm decreases with increasing pH and O170 shows the fluorescence intensity at 655 nm increases with increasing pH. The ratio of fluorescence intensities at 575 and 655 nm has a linear relationship with pH value in the 1.6-13.2 range. The ratiometric sensing approach presented in this study has the advantage of suppressing spurious fluctuations in the intensity of the excitation source and optical transmission properties of the optical fiber. [ABSTRACT FROM AUTHOR]

Industrial output of electrical engineering shapes, i.e., rectangular sections intended for preparing various components by cold forming, and wedge-shaped sections for electrical machine commutators, is assimilated using a contemporary rolling and drawing unit based on planned rolling regimes and repeated drawing with sliding. Contact wires are also produced for overhead town electrical transport networks (trolleybuses, tramways). [ABSTRACT FROM AUTHOR]

The present study has investigated two effective routes to improve the response time and the detection range for the n-MoS 2 /p-CuO (conventional p-n) heterojunction. In the first rectification, an insulating AlN layer was inserted between the MoS 2 and CuO layer, which leads the traditional p-n junction to Semiconductor-Insulator-Semiconductor (SIS) with a superior carrier tunneling mechanism. Interestingly, the fabricated heterostructure exhibits self-powered and broad-range photoresponse. The response time (rise time and fall time) of the fabricated n-MoS 2 /p-CuO heterojunction decreases from 93.35 ms to 102.68 ms–11.31 ms and 12.73 ms with the insertion of ultrathin insulating AlN Layer. The higher responsivity and ultrafast photoresponse in n-MoS 2 /AlN/p-CuO (SIS) heterojunction can be ascribed to the carrier tunneling mechanism through the ultrathin-insulating AlN layer. In the second rectification, the detection range can be enhanced up to the UV region by adding a layer of MoS 2 quantum dots (QDs) on the surface of the MoS 2 layer. The fabricated n-MoS 2 QDs/n-MoS 2 /AlN/p-CuO heterostructure shows photoresponse in a broad range from UV to NIR radiations. The obtained results demonstrate the n-MoS 2 /AlN/p-CuO (SIS) heterostructure with the addition of MoS 2 QDs shows excellent potential for next-generation ultrafast optoelectronics applications. • n-MoS 2 /p-CuO and n-MoS 2 /AlN/p-CuO heterostructures were fabricated via sputtering. • Carrier tunneling is a better transport mechanism for optoelectronics applications. • The n-MoS 2 /AlN/p-CuO heterostructure exhibits higher photocurrent and responsivity. • With the insertion of the AlN layer, the response time (τ r /τ f) decreased from 93.35 ms/102.68 ms–11.31 ms/12.73 ms. • Additionally, MoS 2 QDs have been added to the fabricated heterostructures to increase the detection range. [ABSTRACT FROM AUTHOR]

• Panfungal PCR using NL1/NL4 primers cross reacts with eukaryotic DNA such as T. vaginalis. • Broad range PCR can use such crossreactivity to diagnose unsuspected pathogens. • In particular settings, it should be used to detect pathogens across kingdoms. We report the unusual diagnosis of trichomoniasis in an 18 year old patient suffering from salpingitis. Chlamydiae , Mycoplasma and Gardnerella vaginalis were diagnosed using classic laboratory procedures. However, T. vaginalis infection was assessed fortuitously by Polymerase Chain Reaction (PCR) followed by sequencing using panfungal primers (NL1 / NL4) on a vaginal swab. This cross-reactivity of panfungal primers was further confirmed using a specific T. vaginalis PCR as well as a reference strain of T. vaginalis isolated in culture. Such cross-reactivity of panfungal primers has been previously reported with non-fungal eukaryotes (Taenia solium , Strongyloides stercoralis or Toxoplasma gondii DNA). This case highlights the usefulness of broad range molecular tools that can take advantage of this cross-reactivity in order to diagnose unsuspected pathogens. In particular settings (e.g. immunosuppression, infection without etiology) it should be used to detect pathogens across kingdoms. Thus, such tools would help direct care providers toward appropriate treatment regimens and better management of unsuspected infection etiologies. [ABSTRACT FROM AUTHOR]

A 42-year-old male patient with a history of diffuse large B-cell non-Hodgkin's lymphoma (DLBCL) developed a central line-related bacteremia due to the presence of a Gram-negative bacillus, which was difficult to identify conventionally. Sequencing of a partial region of the 16S rRNA gene identified the organism as Roseomonas mucosa with a homology score of 100% with 1003 bases called. Due to difficulties with the phenotypic identification of this genus, coupled with its emergence in line-related bacteremia in hematology patients with malignancy, Roseomonas spp. should be considered in cases of line-related infection in such patients with atypical Gram-negative organisms. Although several cases have been reported in the literature of line-related sepsis due to Roseomonas gilardii, only a few cases have been reported of Roseomonas mucosa infection in patients with hematological malignancy. This report highlights the benefits of the integration of a sequence-based typing approach in the identification of difficult-to-identify bacterial isolates employing partial regions of the 16S rRNA gene. Continued routine adoption of such techniques by clinical diagnostic laboratories may prove beneficial for the correct identification of blood-borne infections, as well as for the correct epidemiological characterization of unusual causal agents of bacteremia in immunocompromised individuals. [ABSTRACT FROM AUTHOR]

• In-line MZ interferometers in bimodal optical fibers are fabricated and studied. • A broad spectral range of operation from 500 nm to 1700 nm is observed. • Analysis of the wavelength dependence of sensitivity and free spectral range is performed. • Material dispersion of the fiber and surrounding medium is taken into account. • Relative coupled power and visibility are analyzed theoretically and experimentally. We report on the fabrication and study of a broad range microcavity in-line Mach-Zehnder Interferometers (BR-μIMZI) operating in the range from 500 nm to 1700 nm. The BR-μIMZI is based on a single-mode fiber in the near-infrared (NIR) range. For wavelengths above the cut-off wavelength λ c , the interferometric responses are due to the fundamental LP 01 mode, while below λ c – to the second LP 11 mode. We derive expressions for the spectral dependencies of the sensitivity to surrounding refractive index (SRI) changes and of the free spectral range (FSR) taking into account the material dispersion of the fiber and the SRI which are confirmed by experimental measurements. The expression for the relation between relative coupled power and visibility have been derived and experimentally measured. [ABSTRACT FROM AUTHOR]

Broad-range PCR targeting 28S D1-D2 ribosomal DNA (rDNA) identifies numerous fungi but has limited sensitivity in clinical specimens. Ribosomal RNA (rRNA) vastly outnumbers rDNA, suggesting reverse transcription (RT)-PCR could improve detection. Among contrived samples, RT-PCR decreased 28S PCR cycle threshold values by 10--12 cycles and lowered the limit of detection > 2000-fold. Among 32 bronchoalveolar lavage specimens, RT-PCR detected 12/15 (80%) fungal PCR- or culture-positive specimens, versus 6/12 (50%) by 28S PCR, 9/12 (75%) by any fungal PCR, and 13/15 (87%) by culture. RT-PCR newly identified fungi in 4/17 (24%) PCR- and culture-negative specimens. RT substantially increased 28S PCR sensitivity overall., Lay Summary: Fungal infection remains difficult to diagnose in the laboratory. Here, we have shown that detecting ribosomal RNA and DNA, rather than only ribosomal DNA, in a broad range fungal assay results in a significant enhancement in the ability to detect and identify fungal pathogens in clinical samples., (© The Author(s) 2021. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.)

• Generation of monoclonal antibody (Mab-PAR-1) against human parechovirus. • Mab-PAR-1 has broad reactivity against several clinical human parechovirus isolates. • Mab-PAR-1 could potentiate cellular work in human parechovirus study and research. Parechoviruses (PeVs) are common viruses that cause mild gastrointestinal or respiratory symptoms to severe central nervous system infections. In infants, parechovirus infection is one of the leading causes of life-threatening viral disease. High-quality antibodies with broad binding specificities are essential to improve accurate parechovirus diagnosis in diagnostic laboratories. Such antibodies have potential in the development of rapid antigen detection assay against PeVs. In the present study, VP4 and VP2 genes from human parechovirus A1 (PeV-A1) were cloned and VP0 fusion protein produced to develop monoclonal antibodies against PeVs. Two pan-parechovirus antibodies, one IgG and one IgM isotype, were isolated. The properties of IgG1/κ monoclonal (designated as Mab-PAR-1) was studied further. Mab-PAR-1 was shown to be functional in western blot against denatured recombinant protein and viral particles. In immunofluorescence assay, the antibody tested positive for nineteen PeV-A1 isolates while showing no cross-reactivity to fourteen entero- and rhinovirus types. In addition, Mab-PAR-1 showed positive reactivity against five other cultivable parechovirus types 2−6. A unique Mab-PAR-1 epitope located in the junction of the three capsid proteins VP0, VP1, and VP3 was identified using a peptide library screen. This study demonstrates that PeV-A1-VP0 protein is functional antigen for developing monoclonal antibody for diagnosis of broad range of parechovirus infections. [ABSTRACT FROM AUTHOR]

The broad-range detection and identification of bacterial DNA from clinical specimens are a foundational approach in the practice of molecular microbiology. However, there are circumstances under which conventional testing may yield false-negative or otherwise uninterpretable results, including the presence of multiple bacterial templates or degraded nucleic acids. Here, we describe an alternative, next-generation sequencing approach for the broad range detection of bacterial DNA using broad-range 16S rRNA gene hybrid capture ("16S Capture"). The method is able to deconvolute multiple bacterial species present in a specimen, is compatible with highly fragmented templates, and can be readily implemented when the overwhelming majority of nucleic acids in a specimen derive from the human host. We find that this approach is sensitive to detecting as few as 17 Staphylococcus aureus genomes from a background of 100 ng of human DNA, providing 19- to 189-fold greater sensitivity for identifying bacterial sequences than standard shotgun metagenomic sequencing, and is able to successfully recover organisms from across the eubacterial tree of life. Application of 16S Capture to a proof-of-principle case series demonstrated its ability to identify bacterial species that were consistent with histological evidence of infection, even when diagnosis could not be established using conventional broad range bacterial detection assays. 16S Capture provides a novel means for the efficient and sensitive detection of bacteria embedded in human tissues and for specimens containing highly fragmented template DNA., (Copyright © 2020 American Society for Microbiology.)

Prosthetic joint infections (PJI) can be broadly classed into two groups: those where there is a strong clinical suspicion of infection and those with clinical uncertainty, including ‘aseptic loosening’. Confirmation of infection and identification of the causative organism along with provision of antibiotic susceptibility data are important stages in the management of PJI. Conventional microbiological culture and susceptibility testing is usually sufficient to provide this. However, it may fail due to prior antimicrobial treatment or the presence of unusual and fastidious organisms. Molecular techniques, in particular specific real-time and broad-range PCR, are available for diagnostic use in suspected PJI. In this review, we describe the techniques available, their current strengths, limitations and future development. Real-time pathogen-specific and broad-range PCR (with single sequence determination) are suitable for use as part of the routine diagnostic algorithm for clinically suspected PJI. Further development of broad-range PCR with high-throughput (next-generation) sequencing is necessary to understand the microbiome of the prosthetic joint further before this technique can be used for routine diagnostics in clinically unsuspected PJI, including aseptic loosening. [ABSTRACT FROM PUBLISHER]