scholarly journals Radiation Safety Exploration Using Radio-photoluminescence Dosimeter for Crookes Tubes in Junior and Senior High School in Japan

2021 ◽  
Vol 46 (3) ◽  
pp. 106-111
Author(s):  
Masafumi Akiyoshi ◽  
Duy Khiem Do ◽  
Ichiro Yamaguchi ◽  
Tomohisa Kakefu ◽  
Toshiharu Miyakawa
Keyword(s):  
High Schools ◽  
Low Energy ◽  
X Rays ◽  
Dose Equivalent ◽  
The Public ◽  
Peak Energy ◽  
Before And After ◽  
Radiological Education ◽  
Full Power ◽  
Safety Operation

Background: Crookes tube is utilized in junior high and high schools in Japan to study the character of electrons and current, and not for radiological education. There is no official guideline or regulation for these radiation source to the public. Therefore, most teachers have no information about the leakage of X-rays from Crookes tube. The peak energy of X-rays is approximately 20 keV, and it is impossible to measure using conventional survey meters.Materials and Methods: Each leakage dose of low energy X-rays from 38 Crookes tube in the education field, such as junior and senior high schools in Japan, was explored by the teachers in the school using radio-photoluminescence (RPL) dosimeters. Before and after the measurements, the dosimeters were sent by postal mails.Results and Discussion: At the exploration in this study, it was estimated that the 70 μm dose equivalent, Hp(0.07) of X-rays from 31 Crookes tubes were smaller than 100 μSv in 10 minutes, at the distance of 1 m, where the Crookes tube was usually observed. However, the highest dose was estimated as 0.69 mSv by an equipment with the full power. Furthermore, one Crookes tube exhibited 0.62 mSv with minimum output power of the induction coil. This relatively large dose was reduced by the shorter distance of discharge electrodes of the induction coil.Conclusion: The leakage dose of low energy X-rays from 38 Crookes tube was explored using RPL dosimeters. It was estimated that the Hp(0.07) of X-rays from 31 Crookes tubes were smaller than 100 μSv in 10 minutes at the distance of 1 m, while some equipment radiated a higher dose. With this study, the provisional guideline for the safety operation of Crookes tube is established.

scholarly journals Calibration and measurement of X-ray personal dose equivalent with a Hp(10) ionization chamber

2021 ◽  
pp. 19-19
Author(s):  
Yang Xu ◽  
Rui Zhao
Keyword(s):  
Energy Range ◽  
Ionization Chamber ◽  
Conversion Coefficient ◽  
Low Energy ◽  
X Rays ◽  
Correction Factors ◽  
Dose Equivalent ◽  
X Ray ◽  
Conversion Coefficients ◽  
Small Change

The value of personal dose equivalent at10 mm depth is to characterize the energy deposition of strong penetrating radiation in human body and is derived by measurement of air kerma and application of conversion coefficients from ISO report. However, the conversion coefficients depend strongly on the photon energy and angles of incidence for low-energy photons. In order to overcome the problem that the conversion coefficient of low energy rays changes greatly due to the small change of energy, a secondary standard ionization chamber was used to measure personal dose equivalent directly. A matched reference field was established with (20-250) kV X-rays and correction factors with Hp(10) chamber were calculated under these radiation qualities with different angles of incidence. The results showed that the differences were almost 22.7 % of correction factors for the low energy photons at angles of incidence 0?. With conversion coefficient recommended in ISO 4037-3-2019, performance of the chamber response with respect to Hp(10) in the energy range from 33 keV to 208 keV was within about ?10%, and in the energy range from 12 keV to 208 keV and for angles of incidence between 0? and 75? was within about ?19%.

A novel approach towards the calculation of dose rate constants for ambient dose equivalent H∗(10) by including low energy x-rays

2021 ◽  
pp. 109964
Author(s):  
Christoph Stettner ◽  
Nadine Baumgartner ◽  
Christian Hranitzky ◽  
Karin Poljanc ◽  
Hannes Stadtmann ◽  
...  
Keyword(s):  
Dose Rate ◽  
Rate Constants ◽  
Low Energy ◽  
X Rays ◽  
Dose Equivalent ◽  
Novel Approach ◽  
Ambient Dose Equivalent ◽  
Ambient Dose

The Clinical, Roentgenological and Morphological Effects of an Acute Exposure of Phosgene on the Lungs of Dogs

1971 ◽  
Vol 29 ◽  
pp. 236-237
Author(s):  
R. F. Bils ◽  
W. F. Diller ◽  
F. Huth
Keyword(s):  
Latent Period ◽  
Chemical Industry ◽  
Toxic Substance ◽  
Lung Edema ◽  
X Rays ◽  
Beagle Dogs ◽  
Male And Female ◽  
Morphological Alterations ◽  
Before And After ◽  
Electron Microscopes

Phosgene still plays an important role as a toxic substance in the chemical industry. Thiess (1968) recently reported observations on numerous cases of phosgene poisoning. A serious difficulty in the clinical handling of phosgene poisoning cases is a relatively long latent period, up to 12 hours, with no obvious signs of severity. At about 12 hours heavy lung edema appears suddenly, however changes can be seen in routine X-rays taken after only a few hours' exposure (Diller et al., 1969). This study was undertaken to correlate these early changes seen by the roengenologist with morphological alterations in the lungs seen in the'light and electron microscopes.Forty-two adult male and female Beagle dogs were selected for these exposure experiments. Treated animals were exposed to 94.5-107-5 ppm phosgene for 10 min. in a 15 m3 chamber. Roentgenograms were made of the thorax of each animal before and after exposure, up to 24 hrs.

Chemical Species Identification in an SEM by Changes in Emitted X-Ray Energies

1974 ◽  
Vol 32 ◽  
pp. 570-571
Author(s):  
R. H. Duff
Keyword(s):  
Species Identification ◽  
Valence Electron ◽  
Chemical Species ◽  
X Rays ◽  
Chemical Bonds ◽  
Small Shift ◽  
X Ray ◽  
Electron Transitions ◽  
Peak Energy ◽  
Chemical Combination

A material irradiated with electrons emits x-rays having energies characteristic of the elements present. Chemical combination between elements results in a small shift of the peak energies of these characteristic x-rays because chemical bonds between different elements have different energies. The energy differences of the characteristic x-rays resulting from valence electron transitions can be used to identify the chemical species present and to obtain information about the chemical bond itself. Although these peak-energy shifts have been well known for a number of years, their use for chemical-species identification in small volumes of material was not realized until the development of the electron microprobe.

The Challenges in Dealing with Organized Crime and its Consequences in Modern Societies in Albania, Kosovo and Macedonia – the Balkan Peninsula

2015 ◽  
Vol 5 (1) ◽  
pp. 161
Author(s):  
Bashkim Selmani ◽  
Bekim Maksuti
Keyword(s):  
Organized Crime ◽  
Balkan Peninsula ◽  
Human Mind ◽  
Negative Consequences ◽  
The Public ◽  
Before And After ◽  
History Of ◽  
European Standards ◽  
Organized Crime Groups ◽  
Further Development

The profound changes within the Albanian society, including Albania, Kosovo and Macedonia, before and after they proclaimed independence (in exception of Albania), with the establishment of the parliamentary system resulted in mass spread social negative consequences such as crime, drugs, prostitution, child beggars on the street etc. As a result of these occurred circumstances emerged a substantial need for changes within the legal system in order to meet and achieve the European standards or behaviors and the need for adoption of many laws imported from abroad, but without actually reading the factual situation of the psycho-economic position of the citizens and the consequences of the peoples’ occupations without proper compensation, as a remedy for the victims of war or peace in these countries. The sad truth is that the perpetrators not only weren’t sanctioned, but these regions remained an untouched haven for further development of criminal activities, be it from the public state officials through property privatization or in the private field. The organized crime groups, almost in all cases, are perceived by the human mind as “Mafia” and it is a fact that this cannot be denied easily. The widely spread term “Mafia” is mostly known around the world to define criminal organizations.The Balkan Peninsula is highly involved in these illegal groups of organized crime whose practice of criminal activities is largely extended through the Balkan countries such as Kosovo, Albania, Macedonia, Serbia, Bosnia, Croatia, Montenegro, etc. Many factors contributed to these strategic countries to be part of these types of activities. In general, some of the countries have been affected more specifically, but in all of the abovementioned countries organized crime has affected all areas of life, leaving a black mark in the history of these states.

Real Earnings Management before and after Reporting SOX 404 Material Weaknesses

2015 ◽  
Vol 30 (1) ◽  
pp. 119-141 ◽  
Author(s):  
Tuukka Järvinen ◽  
Emma-Riikka Myllymäki
Keyword(s):  
Earnings Management ◽  
Internal Control ◽  
Internal Controls ◽  
Real Earnings Management ◽  
Public Disclosure ◽  
High Quality ◽  
The Public ◽  
Material Weaknesses ◽  
Internal Control System ◽  
Before And After

SYNOPSIS The purpose of this study is to investigate whether SOX Section 404 material weaknesses manifest in real earnings management behavior. The empirical findings indicate that, compared to companies with effective internal controls, companies with existing material weaknesses in their internal controls engage in more manipulation of real activities (particularly inventory overproduction). This implies that the weak commitment by management to provide effective internal control system and high-quality financial information relates to a tendency to use real earnings management methods. Moreover, we find evidence suggesting that companies employ real earnings management (overproduction and reduction of discretionary expenses) after disclosing previous year's material weaknesses. We conjecture that the public disclosure of material weaknesses induces management to strive to mitigate the expected negative reactions of stakeholders to the disclosure by engaging in real earnings management, which is not easily detected or constrained by outsiders. Overall, this study suggests that material weaknesses in internal controls signal an environment where management is more inclined to employ real earnings management.

Financial Crises and the Public Discourse on Financial Elites

2018 ◽  
Author(s):  
Youssef Cassis ◽  
Giuseppe Telesca
Keyword(s):  
Great Depression ◽  
Great Recession ◽  
Public Discourse ◽  
Codes Of Conduct ◽  
The Public ◽  
The Great Recession ◽  
The Great Depression ◽  
Early Twenty ◽  
Before And After ◽  
Late Twentieth

Why were elite bankers and financiers demoted from ‘masters’ to ‘servants’ of society after the Great Depression, a crisis to which they contributed only marginally? Why do they seem to have got away with the recent crisis, in spite of their palpable responsibilities in triggering the Great Recession? This chapter provides an analysis of the differences between the bankers of the Great Depression and their colleagues of the late twentieth/early twenty-first century—regarding their position within, and attitude towards the firm, work culture, mental models, and codes of conduct—complemented with a scrutiny of the public discourse on bankers and financiers before and after the two crises. The authors argue that the (relative) mildness of the Great Recession, compared to the Great Depression, has contributed to preserve elite bankers’ and financiers’ status, income, wealth, and influence. Yet, the long-term consequences of their loss of reputational capital are difficult to assess.

Funding models and expenditures with primary healthcare in Salvador, Bahia, Brazil metropolitan area

2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
T Vivas ◽  
M Duarte ◽  
A Pitta ◽  
B Christovam
Keyword(s):  
Public Health ◽  
Metropolitan Area ◽  
Primary Healthcare ◽  
Healthcare Services ◽  
Ministry Of Health ◽  
Healthcare Budget ◽  
Health Budget ◽  
The Public ◽  
Before And After ◽  
The Government

Abstract Background The government investments in quality primary healthcare are the basis to strengthening the health systems and monitoring the public expenditure in this area is a way to assess the effectiveness and efficiency of the public health policies. The Brazil Ministry of Health changed, in 2017, the method of onlending federal resources to states and cities seeking to make the public funds management more flexible. This change, however, suppressed mandatory investments in primary healthcare. This research aims to determine the difference of expenditures on primary healthcare in Salvador, Bahia, Brazil metropolitan area before and after this funding reform, seeking to verify how it can impact the quality of primary healthcare services and programs. Methods This is an ecological time-series study that used data obtained in the Brazil Ministry of Health budget reports. The median and interquartile range of expenditures on primary healthcare (set as the percentage of total public health budget applied in primary care services and programs) of the 13 cities in the Salvador metropolitan area were compared two years before and after the reform. Results The median of expenditures on primary healthcare in Salvador metropolitan area was 25.5% (13,9% - 32,2%) of total public health budget before and 24.8% (20.8% - 30.0%) of total public health budget after the reform (-0.7% difference). Seven cities decreased the expenditures on primary healthcare after the reform, ranging from 1.2% to 10.8% reduction in the primary healthcare budget in five years. Conclusions Expenditures on primary healthcare in Salvador metropolitan area decreased after the 2017 funding reform. Seven of 13 cities reduced the government investments on primary healthcare services and programs in this scenario. Although the overall difference was -0.7%, the budget cuts ranged from 1.2% to 10.8% in the analyzed period and sample. More studies should assess these events in wide areas and with long time ranges. Key messages Public health funding models can impact the primary healthcare settings regardless of the health policy. Reforms in the funding models should consider the possible benefits before implementation. Funding models and methods that require mandatory investments in primary healthcare may be considered over more flexible ones.

scholarly journals The Inverse Spacer—A Novel, Safe, and Cost-Effective Approach in Routine Procedures for Revision Knee Arthroplasty

2021 ◽  
Vol 10 (5) ◽  
pp. 971
Author(s):  
Kristoff Hammerich ◽  
Jens Pollack ◽  
Alexander F. Hasse ◽  
André El Saman ◽  
René Huber ◽  
...  
Keyword(s):  
Knee Arthroplasty ◽  
Clinical Success ◽  
Cost Effective ◽  
Revision Total Knee Arthroplasty ◽  
Rotational Stability ◽  
X Rays ◽  
Free Interval ◽  
Major Disadvantage ◽  
Cost Effective Approach ◽  
Before And After

Background: A major disadvantage of current spacers for two-stage revision total knee arthroplasty (R-TKA) is the risk of (sub-) luxation during mobilization in the prosthesis-free interval, limiting their clinical success with detrimental consequences for the patient. The present study introduces a novel inverse spacer, which prevents major complications, such as spacer (sub-) luxations and/or fractures of spacer or bone. Methods: The hand-made inverse spacer consisted of convex tibial and concave femoral components of polymethylmethacrylate bone cement and was intra-operatively molded under maximum longitudinal tension in 5° flexion and 5° valgus position. Both components were equipped with a stem for rotational stability. This spacer was implanted during an R-TKA in 110 knees with diagnosed or suspected periprosthetic infection. Postoperative therapy included a straight leg brace and physiotherapist-guided, crutch-supported mobilization with full sole contact. X-rays were taken before and after prosthesis removal and re-implantation. Results: None of the patients experienced (sub-) luxations/fractures of the spacer, periprosthetic fractures, or soft tissue compromise requiring reoperation. All patients were successfully re-implanted after a prosthesis-free interval of 8 weeks, except for three patients requiring an early exchange of the spacer due to persisting infection. In these cases, the prosthetic-free interval was prolonged for one week. Conclusion: The inverse spacer in conjunction with our routine procedure is a safe and cost-effective alternative to other articulating or static spacers, and allows crutch-supported sole contact mobilization without major post-operative complications. Maximum longitudinal intra-operative tension in 5° flexion and 5° valgus position appears crucial for the success of surgery.

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