scholarly journals A Barcoded Polymer-Based Cross-Reactive Spectroscopic Sensor Array for Organic Volatiles

Sensors ◽  
2019 ◽  
Vol 19 (17) ◽  
pp. 3683 ◽  
Author(s):  
Jessica E. Fitzgerald ◽  
Jianliang Shen ◽  
Hicham Fenniri
Keyword(s):  
Sensor Arrays ◽  
Porous Polymer ◽  
Sensing Element ◽  
Electronic Noses ◽  
Non Invasive ◽  
Target Analytes ◽  
Before And After ◽  
Organic Volatiles ◽  
Metabolite Detection ◽  
Array Format

The development of cross-reactive sensor arrays for volatile organics (electronic noses, e-noses) is an active area of research. In this manuscript, we present a new format for barcoded polymer sensor arrays based on porous polymer beads. An array of nine self-encoded polymers was analyzed by Raman spectroscopy before and after exposure to a series of volatile organic compounds, and the changes in the vibrational fingerprints of their polymers was recorded before and after exposure. Our results show that the spectroscopic changes experienced by the porous spectroscopically encoded beads after exposure to an analyte can be used to identify and classify the target analytes. To expedite this analysis, analyte-specific changes induced in the sensor arrays were transformed into a response pattern using multivariate data analysis. These studies established the barcoded bead array format as a potentially effective sensing element in e-nose devices. Devices such as these have the potential to advance personalized medicine, providing a platform for non-invasive, real-time volatile metabolite detection.

scholarly journals Cerebellar rTMS in PSP: a Double-Blind Sham-Controlled Study Using Mobile Health Technology

2021 ◽  
Author(s):  
Andrea Pilotto ◽  
Maria Cristina Rizzetti ◽  
Alberto Lombardi ◽  
Clint Hansen ◽  
Michele Biggi ◽  
...  
Keyword(s):  
Digital Technology ◽  
Repetitive Transcranial Magnetic Stimulation ◽  
Health Technology ◽  
Controlled Study ◽  
Double Blind ◽  
Non Invasive ◽  
Lower Back ◽  
Before And After ◽  
Double Blind Design ◽  
Theta Burst

AbstractThere are no effective treatments in progressive supranuclear palsy (PSP). The aim of this study was to test the efficacy of theta burst repetitive transcranial magnetic stimulation (rTMS) on postural instability in PSP. Twenty PSP patients underwent a session of sham or real cerebellar rTMS in a crossover design. Before and after stimulation, static balance was evaluated with instrumented (lower back accelerometer, Rehagait®, Hasomed, Germany) 30-s trials in semitandem and tandem positions. In tandem and semitandem tasks, active stimulation was associated with increase in time without falls (both p=0.04). In the same tasks, device-extracted parameters revealed significant improvement in area (p=0.007), velocity (p=0.005), acceleration and jerkiness of sway (p=0.008) in real versus sham stimulation. Cerebellar rTMS showed a significant effect on stability in PSP patients, when assessed with mobile digital technology, in a double-blind design. These results should motivate larger and longer trials using non-invasive brain stimulation for PSP patients.

scholarly journals Modular Breath Analyzer (MBA): Introduction of a Breath Analyzer Platform Based on an Innovative and Unique, Modular eNose Concept for Breath Diagnostics and Utilization of Calibration Transfer Methods in Breath Analysis Studies

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3776
Author(s):  
Carsten Jaeschke ◽  
Marta Padilla ◽  
Johannes Glöckler ◽  
Inese Polaka ◽  
Martins Leja ◽  
...  
Keyword(s):  
Real Life ◽  
Sensor Arrays ◽  
Breath Analysis ◽  
Exhaled Breath ◽  
Calibration Transfer ◽  
Early Disease Detection ◽  
Exhaled Breath Analysis ◽  
Breath Analyzer ◽  
Analysis Experiment ◽  
Before And After

Exhaled breath analysis for early disease detection may provide a convenient method for painless and non-invasive diagnosis. In this work, a novel, compact and easy-to-use breath analyzer platform with a modular sensing chamber and direct breath sampling unit is presented. The developed analyzer system comprises a compact, low volume, temperature-controlled sensing chamber in three modules that can host any type of resistive gas sensor arrays. Furthermore, in this study three modular breath analyzers are explicitly tested for reproducibility in a real-life breath analysis experiment with several calibration transfer (CT) techniques using transfer samples from the experiment. The experiment consists of classifying breath samples from 15 subjects before and after eating a specific meal using three instruments. We investigate the possibility to transfer calibration models across instruments using transfer samples from the experiment under study, since representative samples of human breath at some conditions are difficult to simulate in a laboratory. For example, exhaled breath from subjects suffering from a disease for which the biomarkers are mostly unknown. Results show that many transfer samples of all the classes under study (in our case meal/no meal) are needed, although some CT methods present reasonably good results with only one class.

scholarly journals CT perfusion in peripheral arterial disease—hemodynamic differences before and after revascularisation

2021 ◽  
Author(s):  
Patrick Veit-Haibach ◽  
Martin W. Huellner ◽  
Martin Banyai ◽  
Sebastian Mafeld ◽  
Johannes Heverhagen ◽  
...  
Keyword(s):  
Peripheral Arterial Disease ◽  
Ct Perfusion ◽  
Arterial Disease ◽  
Lower Leg ◽  
Therapy Control ◽  
Non Invasive ◽  
Before And After ◽  
Invasive Method ◽  
The Mean ◽  
Peripheral Arterial

Abstract Objectives The purpose of this study was the assessment of volumetric CT perfusion (CTP) of the lower leg musculature in patients with symptomatic peripheral arterial disease (PAD) before and after interventional revascularisation. Methods Twenty-nine consecutive patients with symptomatic PAD of the lower extremities requiring interventional revascularisation were assessed prospectively. All patients underwent a CTP scan of the lower leg, and hemodynamic and angiographic assessment, before and after intervention. Ankle-brachial pressure index (ABI) was determined. CTP parameters were calculated with a perfusion software, acting on a no outflow assumption. A sequential two-compartment model was used. Differences in CTP parameters were assessed with non-parametric tests. Results The cohort consisted of 24 subjects with an occlusion, and five with a high-grade stenosis. The mean blood flow before/after (BFpre and BFpost, respectively) was 7.42 ± 2.66 and 10.95 ± 6.64 ml/100 ml*min−1. The mean blood volume before/after (BVpre and BVpost, respectively) was 0.71 ± 0.35 and 1.25 ± 1.07 ml/100 ml. BFpost and BVpost were significantly higher than BFpre and BVpre in the treated limb (p = 0.003 and 0.02, respectively), but not in the untreated limb (p = 0.641 and 0.719, respectively). Conclusions CTP seems feasible for assessing hemodynamic differences in calf muscles before and after revascularisation in patients with symptomatic PAD. We could show that CTP parameters BF and BV are significantly increased after revascularisation of the symptomatic limb. In the future, this quantitative method might serve as a non-invasive method for surveillance and therapy control of patients with peripheral arterial disease. Key Points • CTP imaging of the lower limb in patients with symptomatic PAD seems feasible for assessing hemodynamic differences before and after revascularisation in PAD patients. • This quantitative method might serve as a non-invasive method, for surveillance and therapy control of patients with PAD.

scholarly journals Characterization and Identification of Varnishes on Copper Alloys by Means of UV Imaging and FTIR

Coatings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 298
Author(s):  
Miriam Truffa Giachet ◽  
Julie Schröter ◽  
Laura Brambilla
Keyword(s):  
Copper Alloys ◽  
Analytical Techniques ◽  
Experimental Methodology ◽  
Artificial Ageing ◽  
Non Invasive ◽  
Uv Imaging ◽  
Before And After ◽  
The Comparative Study ◽  
The 19Th Century ◽  
Analytical Tools

The application of varnishes on the surface of metal objects has been a very common practice since antiquity, both for protective and aesthetic purposes. One specific case concerns the use of tinted varnishes on copper alloys in order to mimic gilding. This practice, especially flourishing in the 19th century for scientific instruments, decorative objects, and liturgical items, results in large museum collections of varnished copper alloys that need to be preserved. One of the main challenges for conservators and restorers deals with the identification of the varnishes through non-invasive and affordable analytical techniques. We hereby present the experimental methodology developed in the framework of the LacCA and VERILOR projects at the Haute École ARC of Neuchâtel for the identification of gold varnishes on brass. After extensive documentary research and analytical campaigns on varnished museum objects, various historic shellac-based varnishes were created and applied by different methods on a range of brass substrates with different finishes. The samples were then characterized by UV imaging and infrared spectroscopy before and after artificial ageing. The comparative study of these two techniques was performed for different thicknesses of the same varnish and for different shellac grades in order to implement an identification methodology based on simple non-invasive examination and analytical tools, which are accessible to conservators.

scholarly journals OCT angiography metrics predict intradialytic hypotension episodes in chronic hemodialysis patients: a pilot, prospective study

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Giuseppe Coppolino ◽  
Adriano Carnevali ◽  
Valentina Gatti ◽  
Caterina Battaglia ◽  
Giorgio Randazzo ◽  
...  
Keyword(s):  
Chronic Hemodialysis ◽  
Dialysis Session ◽  
Intradialytic Hypotension ◽  
Inverse Association ◽  
Non Invasive ◽  
Kaplan Meier ◽  
Optimal Thresholds ◽  
Scanning Area ◽  
Before And After ◽  
Capillary Plexus

AbstractIn chronic hemodialysis (HD) patients, intradialytic hypotension (IDH) is a complication that increases mortality risk. We run a pilot study to analyzing possible relationships between optical coherence tomography angiography (OCT-A) metrics and IDH with the aim of evaluating if OCT-A could represent a useful tool to stratify the hypotensive risk in dialysis patients. A total of 35 eyes (35 patients) were analyzed. OCT-A was performed before and after a single dialysis session. We performed OCT-A 3 × 3 mm and 6 × 6 mm scanning area focused on the fovea centralis. Patients were then followed up to 30 days (10 HD sessions) and a total of 73 IDHs were recorded, with 12 patients (60%) experiencing at least one IDH. Different OCT-A parameters were reduced after dialysis: central choroid thickness (CCT), 6 × 6 mm foveal whole vessel density (VD) of superficial capillary plexus (SPC) and 6 × 6 mm foveal VD of deep capillary plexus (DCP). At logistic regression analysis, IDH was positively associated with baseline foveal VD of SCP and DCP, while an inverse association was found with the choroid. In Kaplan–Meier analyses of patients categorized according to the ROC-derived optimal thresholds, CCT, the 3 × 3 foveal VD of SCP, the 3 × 3 mm and 6 × 6 mm foveal VD of DCP and the 6 × 6 mm foveal VD of SCP were strongly associated with a higher risk of IDH over the 30-days follow-up. In HD patients, a single OCT-A measurement may represent a non-invasive, rapid tool to evaluate the compliance of vascular bed to HD stress and to stratify the risk of IDH in the short term.

Using the Talk Test to Prescribe and Guide Exercise Intensity: Speaking Your Way to Improved Fitness

2018 ◽  
Author(s):  
Nick Preobrazenski
Keyword(s):  
Exercise Intensity ◽  
Ventilatory Threshold ◽  
Peak Oxygen Consumption ◽  
Individual Level ◽  
Non Invasive ◽  
Before And After ◽  
Small Incidence ◽  
Three Stages ◽  
Physiological Markers ◽  
Healthy Males

Introduction: The Talk Test (TT) is a non-invasive, subjective method of prescribing exercise intensity. The TT involves three stages. When exercisers can speak comfortably, can speak but not comfortably, or cannot speak comfortably, they are in the positive (POS), equivocal (EQ), and negative (NEG) TT stages, respectively. The NEG stage correlates with important physiological markers such as ventilatory threshold and lactate threshold. Given the evidence demonstrating large increases peak oxygen consumption (VO2peak) when training at intensities above these markers, the purpose of the study was to test the hypothesis that the TT is efficacious for improving VO2peak at both the group and individual level in young, healthy males. Methods: 11 healthy males completed a maximal fitness test before and after 4 weeks of training 4 times per week for 30 minutes in the NEG stage. The TT was performed every 2.5 to 5 minutes to ensure that the resistance would be enough to elicit a NEG response. Changes in VO2peak below 2 times a previously established typical error were classified as non-response. Results: Four weeks of training at NEG induced a significant increase (11.5%) in VO2peak (PRE: 45.80 mL/Kg/min ± 4.92; POST 51.07 mL/Kg/min ± 5.45, p < 0.001). Furthermore, only one participant (9.09%) was classified as a non-responder in VO2peak following training. Conclusion: These results suggest that the TT can efficaciously prescribe and guide exercise intensity in young, healthy males, and that training at an intensity that prevents comfortable speech leads to a small incidence of non-response

scholarly journals An Experimental Methodology to Evaluate the Rigidity of Penile Prostheses in Vitro

2000 ◽  
Author(s):  
Shyh-Jen Wang
Keyword(s):  
Penile Prosthesis ◽  
Mechanical Failure ◽  
Experimental Methodology ◽  
Prosthetic Material ◽  
Mechanical Measurement ◽  
Hardness Tester ◽  
Non Invasive ◽  
Penile Prostheses ◽  
Before And After

Abstract This work investigates the hardness and buckling force of penile prosthesis to further understand the rigidity of penile prosthesis before and after implantation. Evaluated herein are four prosthetic samples (inflatable 3, semi-rigid 1), five realities (inflatable 1, semi-rigid 4), and one after implantation of prosthesis. The hardness is measured with a hardness tester by pressing the tester’s indentor to the surface of the specimen. In addition, a patient after implantation is evaluated with respect to the hardness of penile versus various numbers of pumping. The buckling force of the prosthesis is also determined by a push-pull gauge and special designed sampling table. Results in this study demonstrate that although the inflatable prosthesis could only be pumped to a certain amount of hardness, hardness and buckling force correlate well with each other. After reaching the extreme hardness, prostheses can even be further pumped a few times. However, continuous pumping only puts more tension on the prosthetic material without increasing any hardness and could induce to mechanical failure of prosthesis. Results also indicate that the buckling force decreases with increasing length of the semi-rigid prostheses, and, then, enlarged when the prosthesis has a larger diameter. This in vitro non-invasive mechanical measurement of the rigidity in penile prosthesis can provide not only clinicians with further information about the penile prosthesis before implantation, but also the patients with more confidence in the prosthesis usage after implantation.

scholarly journals Trochanteric Femur Fractures: Application of Skeletal Traction during Surgery Does Not Alter Soft-Tissue Microcirculation

Medicina ◽  
2021 ◽  
Vol 57 (9) ◽  
pp. 884
Author(s):  
Kenneth P. van Knegsel ◽  
Bergita Ganse ◽  
Pascal C. Haefeli ◽  
Filippo Migliorini ◽  
Mario F. Scaglioni ◽  
...  
Keyword(s):  
Blood Flow ◽  
Soft Tissue ◽  
Oxygen Saturation ◽  
Subcutaneous Tissue ◽  
Skeletal Traction ◽  
Non Invasive ◽  
Femur Fractures ◽  
Vasoactive Factors ◽  
Before And After ◽  
Haemoglobin Content

Background and Objectives: Wound infections provoked by alterations in microcirculation are major complications in the treatment of trochanteric femur fractures. Surgical fracture fixation on a traction table is the gold standard for treatment, but the effect on tissue microcirculation is unknown. Microcirculation could be impaired by the pull on the soft-tissue or by a release of vasoactive factors. We hypothesized that intraoperative traction impairs soft-tissue microcirculation. Materials and Methods: In 22 patients (14 women, eight men), average age 78 years (range 36–96 ± 14), with trochanteric femur fractures, non-invasive laser-Doppler spectrophotometry was used to assess oxygen saturation, hemoglobin content, and blood flow in the skin and subcutaneous tissue before and after application of traction. Measurements were recorded in nine locations around the greater trochanter at a depth of 2, 8, and 15 mm before and after fracture reduction by traction. Results: No differences were found in any depth with traction compared to without (oxygen saturation: p = 0.751, p = 0.308, and p = 0.955, haemoglobin content: p = 0.651, p = 0.928, and p = 0.926, blood flow: p = 0.829, p = 0.866, and p = 0.411). Conclusion: In this pilot study, the application of traction does not affect skin and subcutaneous microcirculation in the surgery of proximal femur fractures.

scholarly journals Electro-haptic hearing: Speech-in-noise performance in cochlear implant users is enhanced by tactile stimulation of the wrists

2019 ◽  
Author(s):  
Mark D. Fletcher ◽  
Amatullah Hadeedi ◽  
Tobias Goehring ◽  
Sean R Mills
Keyword(s):  
Cochlear Implant ◽  
Speech Intelligibility ◽  
Tactile Stimulation ◽  
Electrical Signal ◽  
Noise Performance ◽  
Speech In Noise ◽  
Non Invasive ◽  
Real World Application ◽  
Before And After ◽  
Stimulation Of

Cochlear implant (CI) users receive only limited sound information through their implant, which means that they struggle to understand speech in noisy environments. Recent work has suggested that combining the electrical signal from the CI with a haptic signal that provides crucial missing sound information (“electro-haptic stimulation”; EHS) could improve speech-in-noise performance. The aim of the current study was to test whether EHS could enhance speech-in-noise performance in CI users using: (1) a tactile signal derived using an algorithm that could be applied in real time, (2) a stimulation site appropriate for a real-world application, and (3) a tactile signal that could readily be produced by a compact, portable device. We measured speech intelligibility in multi-talker noise with and without vibro-tactile stimulation of the wrist in CI users, before and after a short training regime. No effect of EHS was found before training, but after training EHS was found to improve the number of words correctly identified by an average of 8.3 %-points, with some users improving by more than 20 %-points. Our approach could offer an inexpensive and non-invasive means of improving speech-in-noise performance in CI users.

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