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 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.

Terracotta polychrome sculptures examined before and after their conservation work: contributions from non-invasive in situ analytical techniques

2011 ◽  
Vol 401 (2) ◽  
pp. 757-765 ◽  
Author(s):  
C. Colombo ◽  
F. Bevilacqua ◽  
L. Brambilla ◽  
C. Conti ◽  
M. Realini ◽  
...  
Keyword(s):  
Analytical Techniques ◽  
Non Invasive ◽  
Before And After

X-Ray Tomography for Electronic Packages

2000 ◽  
Author(s):  
Deepak Goyal
Keyword(s):  
3D Imaging ◽  
Development Time ◽  
Analytical Techniques ◽  
Electronic Packages ◽  
X Ray ◽  
Imaging Capability ◽  
Imaging Results ◽  
Key Drivers ◽  
Analytical Tools ◽  
Non Destructive

Abstract Next generation assembly/package development challenges are primarily increased interconnect complexity and density with ever shorter development time. The results of this trend present some distinct challenges for the analytical tools/techniques to support this technical roadmap. The key challenge in the analytical tools/techniques is the development of non-destructive imaging for improved time to information. This paper will present the key drivers for the non-destructive imaging, results of literature search and evaluation of key analytical techniques currently available. Based on these studies requirements of a 3D imaging capability will be discussed. Critical breakthroughs required for development of such a capability are also summarized.

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 Lost in Migration – Mirandese at a Crossroads

2019 ◽  
Vol 5 (1) ◽  
pp. 488-495
Author(s):  
Cláudia Martins ◽  
Sérgio Ferreira
Keyword(s):  
Minority Language ◽  
Three Dimensions ◽  
Highly Qualified ◽  
Linguistic Rights ◽  
The Bible ◽  
Literary Forms ◽  
Before And After ◽  
The 1960S ◽  
The One ◽  
The 19Th Century

AbstractThe linguistic rights of Mirandese were enshrined in Portugal in 1999, though its “discovery” dates back to the very end of the 19th century at the hands of Leite de Vasconcellos. For centuries, it was the first or only language spoken by people living in the northeast of Portugal, particularly the district of Miranda do Douro. As a minority language, it has always moved among three dimensions. On the one hand, the need to assert and defend this language and have it acknowledged by the country, which proudly believe(d) in their monolingual history. Unavoidably, this has ensued the action of translation, especially active from the mid of the 20th century onwards, with an emphasis on the translation of the Bible and Portuguese canonical literature, as well as other renowned literary forms (e.g. The Adventures of Asterix). Finally, the third axis lies in migration, either within Portugal or abroad. Between the 1950s and the 1960s, Mirandese people were forced to leave Miranda do Douro and villages in the outskirts in the thousands. They fled not only due to the deeply entrenched poverty, but also the almost complete absence of future prospects, enhanced by the fact that they were regarded as not speaking “good” Portuguese, but rather a “charra” language, and as ignorant backward people. This period coincided with the building of dams on the river Douro and the cultural and linguistic shock that stemmed from this forceful contact, which exacerbated their sense of not belonging and of social shame. Bearing all this in mind, we seek to approach the role that migration played not only in the assertion of Mirandese as a language in its own right, but also in the empowerment of new generations of Mirandese people, highly qualified and politically engaged in the defence of this minority language, some of whom were former migrants. Thus, we aim to depict Mirandese’s political situation before and after the endorsement of the Portuguese Law no. 7/99.

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 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.

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