Paper-Based Analytical Devices for Colorimetric and Luminescent Detection of Mercury in Waters: An Overview

Lab-on-paper technologies, also known as paper-based analytical devices (PADs), have received increasing attention in the last years, and nowadays, their use has spread to virtually every application area, i.e., medical diagnostic, food safety, environmental monitoring, etc. Advantages inherent to on-field detection, which include avoiding sampling, sample preparation and conventional instrumentation in central labs, are undoubtedly driving many developments in this area. Heavy metals represent an important group of environmental pollutants that require strict controls due to the threat they pose to ecosystems and human health. In this overview, the development of PADs for Hg monitoring, which is considered the most toxic metal in the environment, is addressed. The main emphasis is placed on recognition elements (i.e., organic chromophores/fluorophores, plasmonic nanoparticles, inorganic quantum dots, carbon quantum dots, metal nanoclusters, etc.) employed to provide suitable selectivity and sensitivity. The performance of both microfluidic paper-based analytical devices and paper-based sensors using signal readout by colorimetry and luminescence will be discussed.

Novel High Accuracy Resolver Topology for Space Applications

In recent years, the space industry has experienced a significant change mainly due to the incursion of private companies, which has shaken up the sector. This new situation allows for a reduction regarding the reliability of conventional instrumentation for space while reducing the development time and manufacturing volume. Consequently, even though it has been typical to use equipment that was previously tested in space, this could be the right moment to introduce new technologies due to the previously mentioned reasons. One of the interesting technologies with great potential is the rotary sensor in applications with motors. Historically, the resistive potentiometer has been the most used due to its simplicity and robustness; however, it has several drawbacks. Due to this, the aim of this paper is to identify an interesting rotary sensor. Hence, in this article, different sensor types are studied. Then, we review the literature regarding resolvers in order to find the best topology. We designed and compared different single speed absolute position resolvers to find the ones that offered the best results. In this process, a novel resolver topology was designed that improved on the performances of any other studied topology.

Comparison of Postoperative Coronal Leg Alignment in Customized Individually Made and Conventional Total Knee Arthroplasty

Neutral coronal leg alignment is known to be important for postoperative outcome in total knee arthroplasty (TKA). Customized individually made implants (CIM) instrumented with patient-specific cutting guides are an innovation aiming to increase the precision and reliability of implant positioning and reconstruction of leg alignment. We aimed to compare reconstruction of the hip–knee–ankle angle (HKA) of the novel CIM system iTotal™ CR G2 (ConforMIS Inc.) to a matched cohort of the off-the-shelf (OTS) knee replacement system Vanguard™ CR (Zimmer Biomet). Retrospective analysis of postoperative coronal full-leg weight-bearing radiographs of 562 TKA (283 CIM TKA, 279 OTS TKA) was conducted. Via a medical planning software, HKA and rotation of the leg were measured in postoperative radiographs. HKA was then adjusted for rotational error, and 180° ± 3° varus/valgus was defined as the target zone HKA. Corrected postoperative HKA in the CIM group was 179.0° ± 2.8° and 179.2° ± 3.1° in the OTS group (p = 0.34). The rate of outliers, outside of the ±3° target zone, was equal in both groups (32.9%). Our analysis showed that TKA using patient-specific cutting guides and implants and OTS TKA implanted with conventional instrumentation resulted in equally satisfying restoration of the coronal leg alignment with less scattering in the CIM group.

IFCC interim guidelines on rapid point-of-care antigen testing for SARS-CoV-2 detection in asymptomatic and symptomatic individuals

With an almost unremittent progression of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections all around the world, there is a compelling need to introduce rapid, reliable, and high-throughput testing to allow appropriate clinical management and/or timely isolation of infected individuals. Although nucleic acid amplification testing (NAAT) remains the gold standard for detecting and theoretically quantifying SARS-CoV-2 mRNA in various specimen types, antigen assays may be considered a suitable alternative, under specific circumstances. Rapid antigen tests are meant to detect viral antigen proteins in biological specimens (e.g. nasal, nasopharyngeal, saliva), to indicate current SARS-CoV-2 infection. The available assay methodology includes rapid chromatographic immunoassays, used at the point-of-care, which carries some advantages and drawbacks compared to more conventional, instrumentation-based, laboratory immunoassays. Therefore, this document by the International Federation for Clinical Chemistry and Laboratory Medicine (IFCC) Taskforce on COVID-19 aims to summarize available data on the performance of currently available SARS-CoV-2 antigen rapid detection tests (Ag-RDTs), providing interim guidance on clinical indications and target populations, assay selection, and evaluation, test interpretation and limitations, as well as on pre-analytical considerations. This document is hence mainly aimed to assist laboratory and regulated health professionals in selecting, validating, and implementing regulatory approved Ag-RDTs.

Preclinical experience with a novel single-port platform for transoral surgery

Background We investigated a novel minimally invasive surgical platform for use in the oropharynx, hypopharynx, and larynx for single-port transoral surgery used in concert with standard transoral laryngeal and pharyngeal instrumentation. Methods The preclinical investigational device by Fortimedix Surgical B.V. (Netherlands) features two channels for manually controlled flexible articulating surgical instruments. A third central channel accepts both rigid and flexible endoscopes. The system is coupled to a standard laryngoscope for transoral access. In three cadaver models, we evaluated the surgical capabilities using wristed grasping instruments, microlaryngeal scissors, monopolar cautery, and a laser fiber sheath. Procedures were performed within the oropharynx, supraglottis, glottis, subglottis, and hypopharynx. Results Within the oropharynx, we found adequate strength, range of motion, and dexterity to perform lateral oropharyngectomy and tongue base resection. Within the larynx, visualization was achieved with a variety of instruments including a flexible, 0° and 30° rigid endoscope. The glottis, supraglottis, pyriform sinuses, post-cricoid space, and esophageal inlet were readily accessible. Visualization and manipulation of grasping, laser, and monopolar cautery instruments were also possible within the subglottis. Instrument reach and accuracy facilitated completion of a delicate micro-flap on the true vocal fold. Other procedures included vocal fold resection, cricopharyngeal myotomy, and resection of subglottic mucosa. Conclusions From this initial proof of concept experience with this novel platform, we found a wide range of procedures within the oropharynx, larynx, and hypopharynx to be feasible. Further work is needed to evaluate its applicability to the clinical setting. The ability of this platform to be used with conventional instrumentation may provide an opportunity for complex transoral surgery to be performed in a facile manner at greatly reduced cost.