scholarly journals Advances in the investigation of shock-induced reflectivity of porous carbon

2013 ◽  
Vol 31 (3) ◽  
pp. 457-464 ◽  
Author(s):  
Dimitri Batani ◽  
Stefano Paleari ◽  
Tommaso Vinci ◽  
Roberto Benocci ◽  
Keisuke Shigemori ◽  
...  
Keyword(s):  
Shock Waves ◽  
Numerical Simulations ◽  
Porous Carbon ◽  
Simultaneous Measurement ◽  
Accurate Determination ◽  
Sample Temperature ◽  
Optical Pyrometry ◽  
Shock Dynamics

AbstractWe studied the behavior of porous carbon compressed by laser-generated shock waves. In particular, we developed a new design for targets, optimized for the investigation of carbon reflectivity at hundred-GPa pressures and eV/k temperatures. Specially designed “two-layer-two materials” targets, comprising porous carbon on transparent substrates, allowed the probing of carbon reflectivity and a quite accurate determination of the position in the P, T plane. This was achieved by the simultaneous measurement of shock breakout times, sample temperature (by optical pyrometry) and uid velocity. The experiments proved the new scheme is reliable and appropriate for reflectivity measurements of thermodynamical states lying out of the standard graphite or diamond hugoniot. An increase of reflectivity in carbon has been observed at 260 GPa and 14,000 K while no increase in reflectivity is found at 200 GPa and 20,000 K. We also discuss the role of numerical simulations in the optimization of target parameters and in clarifying shock dynamics.

scholarly journals The Significance of Death-Scene Investigation in Determining Cause and Circumstances of Medico-Legal Death

2019 ◽  
Vol 24 (38) ◽  
pp. 53-62
Author(s):  
Corina Crișan
Keyword(s):  
Accurate Determination ◽  
Massive Hemoptysis ◽  
Death Scene ◽  
First Case ◽  
Death Scene Investigation ◽  
Traumatic Lesions ◽  
Scene Investigation ◽  
Mechanical Asphyxia

Abstract The article presents two cases of the Arad Medico-Legal Department illustrating just a part of the role of the forensic pathologist at the death scene but there are sufficient to fully justify the importance of this investigation as no example can comprise the complexity of problems and the particularity of each case, nor a statistic can be made. Both cases were found dead at home and forensically autopsied, but the two of them were distinct in terms of forensic pathologist's request death scene participation. In the first case, the autopsy did not find traumatic lesions, but revealed that the death was due to massive hemoptysis caused by cavernous tuberculosis with subsequent exsanguination, microscopically confirmed. The death was nonviolent. In the second case, the autopsy revealed findings of mechanical asphyxia due to neck compression, both macroscopically and microscopically. The death was violent. In both cases the forensic expert participation is required at the death-scene. In the first case it allowed the correct interpretation of the traces of blood found on site, and in the second case, an onsite research would have properly helped for restoring the death‟s occurrence. The scene investigation and autopsy provide, together, the basis for an accurate determination of cause and circumstances of death.

scholarly journals Impact of Sleep Apnea on Cardioembolic Risk in Patients With Atrial Fibrillation

Stroke ◽  
2020 ◽  
Author(s):  
Martino F. Pengo ◽  
Andrea Faini ◽  
Ludger Grote ◽  
Ondrej Ludka ◽  
Pavol Joppa ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Sleep Apnea ◽  
Accurate Determination ◽  
Oxygen Desaturation ◽  
Desaturation Index ◽  
Oxygen Desaturation Index ◽  
Obstructive Sleep ◽  
Initial Cohort

Background and Purpose: An accurate determination of the cardioembolic risk in patients with atrial fibrillation (AF) is crucial to prevent consequences like stroke. Obstructive sleep apnea (OSA) is a known risk factor for both AF and stroke. We aim to explore a possible association between OSA and an increased cardioembolic risk in patients with AF. Methods: We assessed data from the ESADA (European Sleep Apnea Database) cohort where patients with known AF and OSA were included. Parameters of OSA severity and related hypoxia like lowest Sp o 2 and 4% oxygen desaturation index were analyzed. Patients were stratified according to their cardioembolic risk estimated with the CHA 2 DS 2 -VASc score. Results: From the initial cohort of 14 646 patients, a final set of 363 patients were included in the analysis. Indices of hypoxia during sleep were associated with increased CHA 2 DS 2 -VASc score (4% oxygen desaturation index 17.9 versus 29.6 versus 30.5 events/hour and the lowest Sp o 2 81.2 versus 77.8 versus 77.5% for low, moderate, and high cardioembolic risk, respectively, P <0.05). Conclusions: These results support the potential role of OSA-related hypoxia in the risk for cardioembolic complications such as stroke in patients with AF.

Role of fractionation correction in accurate determination of 142Nd/144Nd by TIMS: A case study of 1.48 Ga alkaline rocks from Khariar, India

2017 ◽  
Vol 466 ◽  
pp. 479-490 ◽  
Author(s):  
Ikshu Gautam ◽  
Jyotiranjan S. Ray ◽  
Rajneesh Bhutani ◽  
S. Balakrishnan ◽  
J.K. Dash
Keyword(s):  
Accurate Determination ◽  
Alkaline Rocks

scholarly journals Photometric Variability of OB-type stars as a New Window on Massive Stars

2014 ◽  
Vol 9 (S307) ◽  
pp. 171-175
Author(s):  
M. Kourniotis ◽  
A. Z. Bonanos ◽  
I. Soszyński ◽  
R. Poleski ◽  
G. Krikelis ◽  
...  
Keyword(s):  
Systematic Study ◽  
Massive Stars ◽  
Accurate Determination ◽  
Early Type ◽  
Stellar Rotation ◽  
Photometric Variability ◽  
Fundamental Parameters ◽  
Disk Formation

AbstractWe present the first systematic study of 4646 spectroscopically confirmed early-type massive stars in the Small Magellanic Cloud (SMC), using variability as a tool to confine the physics of OB-type massive stars. We report the discovery of ∼100 massive eclipsing systems which are useful for the accurate determination of the fundamental parameters of massive stars and we evaluate the frequency of multiplicity. In addition, we explore the occurrence of the Oe/Be phenomenon and provide a large number of candidate non-radial pulsators, which can be further studied via asteroseismology. The results of this work (Kourniotis et al. 2014) will contribute to a better understanding of the role of metallicity in triggering processes associated to matter ejections and/or disk formation, which in turn affect mass loss and stellar rotation.

Influence of Sample Temperature for Measurement Accuracy with FT-NIR Spectroscopy

2017 ◽  
Vol 100 (2) ◽  
pp. 499-502 ◽  
Author(s):  
Lukáš Dvořák ◽  
Martin Fajman ◽  
Kvetoslava Sustova
Keyword(s):  
Content Analysis ◽  
Dry Matter ◽  
Measurement Accuracy ◽  
Accurate Determination ◽  
Nir Spectroscopy ◽  
Sample Temperature ◽  
Integrating Sphere ◽  
Milk Samples ◽  
Trajectory Length

Abstract This study monitored the influence of milk samples temperature on the measuring accuracy of FT-NIR spectroscopy in milk content analysis. Reference methods were used to determine dry matter, fat, protein, and lactose content in cow's milk. Milk samples were measured in reflectance mode on an integrating sphere with the use ofa compression cuvette and a transflectance cuvette, ensuring a beam trajectory length of h = 0.2 mm. The samples were measured at 18, 20, 22, 24, and 40°C, and analyses were performed at 100 scansat a resolution of 8 cm−1. The measurements were influenced by the temperatures of the samples during the evaluation of all analyzed constituents (P &lt; 0.05). Our results confirmed that the accurate determination of milk constituents requires maintaining, during analysis, the temperature conditions of the samples and the conditions for which the spectrophotometer calibration was designed.

Groins and submerged breakwaters – new modeling and empirical experience

2016 ◽  
Vol 45 (1) ◽  
Author(s):  
Rafał Ostrowski ◽  
Zbigniew Pruszak ◽  
Jan Schönhofer ◽  
Marek Szmytkiewicz
Keyword(s):  
Baltic Sea ◽  
Numerical Simulations ◽  
Technical Condition ◽  
Theoretical Modeling ◽  
Field Observations ◽  
Rip Current ◽  
Nearshore Zone ◽  
The Relationship

AbstractThe relationship between the effectiveness of groins and their technical condition was studied. The supporting role of groins in artificial shore nourishment was tested using the theoretical modeling of hydrodynamic and morphodynamic processes in the nearshore zone. This modeling scheme was developed as to represent the actual coastal situation occurring on the shores of the Hel Peninsula (the Gulf of Gdańsk, the southern Baltic Sea). Based on the results of computations and the results of field observations, recommendations were prepared on the design and maintenance of groins. The second part of the paper is devoted to submerged breakwaters. The theoretical modeling of wave-current fields near the segmented submerged breakwaters led to the determination of coefficients of wave transmission and rip current velocities, which finally yielded a piece of design advice. In all numerical simulations, the Delft3D software was used.

scholarly journals Perspectives on the History of Bovine TB and the Role of Tuberculin in Bovine TB Eradication

2011 ◽  
Vol 2011 ◽  
pp. 1-11 ◽  
Author(s):  
Margaret Good ◽  
Anthony Duignan
Keyword(s):  
Test Performance ◽  
Bovine Tuberculosis ◽  
Accurate Determination ◽  
Tuberculin Test ◽  
Eradication Programme ◽  
History Of ◽  
Epidemiological Profile ◽  
Significant Disease

Tuberculosis remains a significant disease of animals and humans worldwide. Bovine tuberculosis is caused by Mycobacteria with an extremely wide host range and serious, although currently probably underdiagnosed, zoonotic potential. Where bovine tuberculosis controls are effective, human zoonotic TB, due toMycobacterium bovisorM. caprae, is uncommon and clinical cases are infrequent in cattle. Therefore, the control and ultimate eradication of bovine tuberculosis is desirable. Tuberculin tests are the primary screening tool used in bovine eradication. The choice of tuberculin test is dependent on the environment in which it is to be used. Tuberculin potency is critical to test performance, and the accurate determination of potency is therefore particularly important. The design of a control or eradication programme should take into consideration the fundamental scientific knowledge, the epidemiological profile of disease, the experience of other eradication programmes, and the presence, in the same ecosystem, of maintenance hosts, in which infection is self-sustaining and which are capable of transmitting infection. A control or eradication programme will necessarily require modification as it progresses and must be under constant review to identify the optimal desirable goals, the efficacy of policy, and constraints to progress.

scholarly journals Numerical and experimental evaluation of shock dividers

Shock Waves ◽  
2022 ◽  
Author(s):  
M. Rezay Haghdoost ◽  
B. S. Thethy ◽  
M. Nadolski ◽  
B. Seo ◽  
C. O. Paschereit ◽  
...  
Keyword(s):  
Shock Wave ◽  
Shock Waves ◽  
Numerical Simulations ◽  
Total Pressure ◽  
High Speed ◽  
Pressure Probe ◽  
Width Ratio ◽  
Pressure Pulsations ◽  
Pulse Detonation ◽  
Shock Dynamics

AbstractMitigation of pressure pulsations in the exhaust of a pulse detonation combustor is crucial for operation with a downstream turbine. For this purpose, a device termed the shock divider is designed and investigated. The intention of the divider is to split the leading shock wave into two weaker waves that propagate along separated ducts with different cross sections, allowing the shock waves to travel with different velocities along different paths. The separated shock waves redistribute the energy of the incident shock wave. The shock dynamics inside the divider are investigated using numerical simulations. A second-order dimensional split finite volume MUSCL-scheme is used to solve the compressible Euler equations. Furthermore, low-cost simulations are performed using geometrical shock dynamics to predict the shock wave propagation inside the divider. The numerical simulations are compared to high-speed schlieren images and time-resolved total pressure recording. For the latter, a high-frequency pressure probe is placed at the divider outlet, which is shown to resolve the transient total pressure during the shock passage. Moreover, the separation of the shock waves is investigated and found to grow as the divider duct width ratio increases. The numerical and experimental results allow for a better understanding of the dynamic evolution of the flow inside the divider and inform its capability to reduce the pressure pulsations at the exhaust of the pulse detonation combustor.

Role of Ancillary Testing on Endoscopic US-Guided Fine Needle Aspiration Samples from Cystic Pancreatic Neoplasms

2019 ◽  
Vol 64 (1-2) ◽  
pp. 124-135
Author(s):  
Nirag Jhala ◽  
Piyachat Srimunta ◽  
Darshana Jhala
Keyword(s):  
Multidisciplinary Approach ◽  
Accurate Determination ◽  
Needle Aspiration ◽  
Pancreatic Cysts ◽  
Molecular Testing ◽  
Appropriate Care ◽  
Biochemical Testing ◽  
Single Modality

Pancreatic cysts are increasingly detected on imaging studies. Accurate determination of the cyst type is important to provide appropriate care for the patients. It is also very clear that not one single modality can provide adequate diagnostic information. A multidisciplinary approach is the key to the diagnosis of pancreatic cysts. In this setting, the role of ancillary testing, which includes biochemical testing (carcinoembryonic antigen and amylase levels in the cyst), molecular testing (e.g., KRAS, GNAS, VHL, and CTNB1), and/or immunohistochemical tests are very important to obtain an accurate diagnosis. This review will discuss helpful ancillary tests in common pancreatic cyst neoplasms and how to approach the diagnosis of pancreatic cysts.

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