State-of-the-Art Measurement Instrumentation and Most Recent Measurement Techniques for Parabolic Trough Collector Fields

The presented review gives reliable information about the currently used measurement instrumentation in parabolic trough fields and recent monitoring approaches. The usually built-in measurement equipment in the solar field, clamp-on systems for flexible measurements of temperature and flow, solar irradiance measurements, standard meteorological equipment, laboratory devices for heat transfer fluid analyses and instruments related to the tracking of solar collector assemblies are presented in detail. The measurement systems are reported with their measurement uncertainty, approximate costs and usual installation location for the built-in instrumentation. Specific findings related to the installation and operation of the measurement devices are presented. The usually installed instrumentation delivers a lot of measurements all over the field at the expense of measurement accuracy, compared to special test facility equipment. Recently introduced measurement approaches can improve the standard instrumentation in terms of accuracy, frequency, spatial distribution or can even extend the amount of measurands. The information about available measurands is the basis for future operation and maintenance solutions based on data-driven approaches.

Total Ankle Arthroplasty Radiographic Alignment Comparison Between Patient-Specific Instrumentation and Standard Instrumentation

Background Several benefits are published supporting patient-specific instrumentation (PSI) in total ankle arthroplasty (TAA). This study seeks to determine if TAA with PSI yields different radiographic outcomes vs standard instrumentation (SI). Methods: Sixty-seven primary TAA patients having surgery using PSI or SI between 2013 and 2015 were retrospectively reviewed using weightbearing radiographs at 6-12 weeks postsurgery. Radiographic parameters analyzed were the medial distal tibia angle (MDTA), talar-tilt angle (TTA), anatomic sagittal distal tibia angle (aSDTA), lateral talar station (LTS), and talar component inclination angle (TCI). A comparison of the 2 groups for each radiologic parameter’s distribution was performed using a nonparametric median test and Fisher exact test. Furthermore, TAAs with all radiographic measurements within acceptable limits were classified as “perfectly aligned.” The rate of “perfectly aligned” TAAs between groups was compared using a Fisher exact test with a significance of .05. Results: Of the 67 TAAs, 51 were done with PSI and 16 with SI. There were no differences between groups in MDTA ( P = .174), TTA ( P = .145), aSDTA ( P = .98), LTS ( P = .922), or TCI angle ( P = .98). When the rate of “perfectly aligned TAA” between the 2 groups were compared, there was no significant difference ( P = .35). Conclusion: No significant radiographic alignment differences were found between PSI and SI implants. This study showed that both techniques achieve reproducible TAA radiographic coronal and sagittal alignment for the tibial component when performed by experienced surgeons. The talar component’s sagittal alignment is similar whether or not PSI was used but is noticeably different from normal anatomic alignment by design. Level of Evidence: Level III, retrospective cohort study using prospectively collected data.

A comparison of the Thunderbeat and standard electrocautery devices in head and neck surgery: a prospective randomized controlled trial

Purpose New energy-based sutureless vessel ligation devices, such as the Thunderbeat (Olympus Medical Systems Corp., Tokyo, Japan), could reduce operative time and limit blood loss in head and neck surgery; however, efficacy and safety in major head and neck surgery have not been investigated in a prospective, randomized study. Methods This prospective, double-arm, randomized controlled trial consisted of two parts: total laryngectomy (TL) and neck dissection (ND). Thirty patients planned for TL were randomized in two groups. For the ND part, forty-two operative sides were likewise randomized. In both parts, Thunderbeat was used in addition to the standard instrumentation in the intervention groups, while only standard instrumentation was used in the control groups. Primary outcome values were blood loss, operative time and complication rate. Results For the TL part there was no difference in mean blood loss (p = 0.062), operative time (p = 0.512) and complications (p = 0.662) between both hemostatic techniques. For the neck dissection part, there was a reduction in blood loss (mean 210 mL versus 431 mL, p = 0.046) and in operative time (median 101 (IQR 85–130) minutes versus 150 (IQR 130–199) minutes, p = 0.014) when Thunderbeat was used. There was no difference in complication rate between both hemostatic systems (p = 0.261). Conclusion The Thunderbeat hemostatic device significantly reduces operative blood loss and operative time for neck dissections, without increase in complications. In TL, blood loss using Thunderbeat was comparable with the standard technique, but the operative time tended to be shorter. Trial registration UMCG Research Register, Reg. no. 201700041, date of registration: 18/1/2017

Innovative boat-towed transient electromagnetics — Investigation of the Furnas volcanic lake hydrothermal system, Azores

Water-covered areas may lead to gaps in surface electromagnetic surveys, causing reduced resolution and, as a consequence, increased uncertainty in derived subsurface models. We have evaluated a boat-towed floating central loop time-domain electromagnetic technique that mitigates this problem. It facilitates obtaining data with a spatial sampling density, which is rarely possible with standard instrumentation on land, and it only requires moderate logistical effort. A unique field study on a shallow volcanic lake demonstrated that this method is feasible with only a minor loss of accuracy when compared to anchored and land soundings. We found that the noise sources arising from the moving instrument and the boat engine can be neglected. The field survey was performed on the Lagoa das Furnas (São Miguel, Azores Islands, Portugal), which is located within an active volcanic area and is characterized by fumarolic fields and [Formula: see text] degassing. Thus, the associated hydrothermal system is expected to extend below the lake. However, the character, geometry, and extent of this system are unknown because of the lack of boreholes and geophysical studies. In total, 600 soundings, combining towed profiles with anchored and land-based soundings, were acquired with an aim of imaging the hydrothermal system beneath the lake down to 200 m. The results from all three types of measurements compare well and thus led to consistent 1D inversion models. The inversion results delineate a highly conductive, smectite-rich cap layer dipping below the lake away from the main fumarole zone. Near this zone, the extent of the conductor agrees well with an area of intense dispersed [Formula: see text] degassing, which appears to be controlled by at least two electrically distinctive fault zones in which the conductor is found at greater depths.

Characterising low-cost sensors in highly portable platforms to quantify personal exposure in diverse environments

The inaccurate quantification of personal exposure to air pollution introduces error and bias in health estimations, severely limiting causal inference in epidemiological research worldwide. Rapid advancements in affordable, miniaturised air pollution sensor technologies offer the potential to address this limitation by capturing the high variability of personal exposure during daily life in large-scale studies with unprecedented spatial and temporal resolution. However, concerns remain regarding the suitability of novel sensing technologies for scientific and policy purposes. In this paper we characterise the performance of a portable personal air quality monitor (PAM) that integrates multiple miniaturised sensors for nitrogen oxides (NOx), carbon monoxide (CO), ozone (O3) and particulate matter (PM) measurements along with temperature, relative humidity, acceleration, noise and GPS sensors. Overall, the air pollution sensors showed high reproducibility (mean R‾2=0.93, min–max: 0.80–1.00) and excellent agreement with standard instrumentation (mean R‾2=0.82, min–max: 0.54–0.99) in outdoor, indoor and commuting microenvironments across seasons and different geographical settings. An important outcome of this study is that the error of the PAM is significantly smaller than the error introduced when estimating personal exposure based on sparsely distributed outdoor fixed monitoring stations. Hence, novel sensing technologies such as the ones demonstrated here can revolutionise health studies by providing highly resolved reliable exposure metrics at a large scale to investigate the underlying mechanisms of the effects of air pollution on health.

Characterising low-cost sensors in highly portable platforms to quantify personal exposure in diverse environments

The inaccurate quantification of personal exposure to air pollution introduces error and bias in health estimations, severely limiting causal inference in epidemiological research worldwide. Rapid advancements in affordable, miniaturised air pollution sensor technologies offer the potential to address this limitation by capturing the high variability of personal exposure during daily life in large-scale studies with unprecedented spatial and temporal resolution. However, concerns remain regarding the suitability of novel sensing technologies for scientific and policy purposes. In this paper we characterise the performance of a portable personal air quality monitor (PAM) that integrates multiple miniaturised sensors for nitrogen oxides (NOx), carbon monoxide (CO), ozone (O3) and particulate matter (PM) measurements along with temperature, relative humidity, acceleration, noise and GPS sensors. Overall, the air pollution sensors showed excellent agreement with standard instrumentation in outdoor, indoor and commuting microenvironments across seasons and different geographical settings. An important outcome of this study is that the error of the PAM is significantly smaller than the error introduced when estimating personal exposure based on sparsely distributed outdoor fixed monitoring stations. Hence, novel sensing technologies as the ones demonstrated here can revolutionise health studies by providing highly resolved reliable exposure metrics at large scale to investigate the underlying mechanisms of the effects of air pollution on health.

Direct superior approach with standard instrumentation for total hip arthroplasty: safety and efficacy in a prospective 200-case series

Introduction: Direct Superior Approach (DSA) is a muscle sparing approach for total hip arthroplasty (THA) implemented using special instrumentation. There is a lack of information in the literature concerning DSA with standard instrumentation. Materials and methods: 238 patients were recruited for primary THA by a single surgeon from January 2016 until May 2017. 209 patients underwent THA through DSA approach with non-offset acetabular reamers and femoral broaches. We evaluated accuracy of implantation, complications and early functional results. Independent orthopaedic surgeons performed the clinical and radiographic assessments. Results: 200 patients were followed for a year. 3 different implants were used. No sciatic nerve palsies, hip dislocations or fractures were recorded. There was one acute deep and superficial wound infection. The mean functional score was significantly improved at all follow-ups ( p < 0.001). 97% of stems were inserted into the neutral coronal and 96% in neutral sagittal alignment. All cups fell within a safe zone of inclination and 91% of anteversion. 2 hips demonstrated heterotopic ossification, Brooker class I. Obese patients had no increased risk of complications. Conclusions: DSA with standard instrumentation is safe and efficacious for THA. It offers fast recovery and facilitates correct implantation of different implants, can be useful even for hip dysplasia and obese patients with minimal complication rates.

Influence of Synthetic Approach of SiO2-ZrO2 Materials

In the present manuscript, the effect of the synthetic route on the properties of SiO2-ZrO2 has been evaluated. Co-precipitation, sol-gel and microwave methods were adopted for synthesizing the structured oxide. The properties of the final products such as surface morphology, crystallinity, surface area, pore volume and size, particle size and total acidity were examined using standard instrumentation like Fe-SEM, XRD, BET and TPD. The results revealed that the mixed oxides were mesoporous in nature with a high BET surface area (315- 435m2/g). Among various methods, the microwave route achieved the highest surface area (433m2/g), pore volume (0.70cc/g) and pore size (6.50nm). The total acidity of the sample synthesized by the microwave reactor was also higher (0.296mmol/g) than that resulting from other methods. Results conclude that microwave method is a suitable choice for synthesizing the structured oxides with desirable properties.