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1.
Tob Control ; 31(4): 511-519, 2022 07.
Article in English | MEDLINE | ID: mdl-33771932

ABSTRACT

INTRODUCTION: There is growing concern about transnational tobacco corporations' (TTCs) and other commercial actors' involvement in e-cigarette policy development. Previous analyses suggest that TTCs used e-cigarette debates to demonstrate alignment with public health and re-gain policy influence. Less is known about the engagement of other types of commercial actors in e-cigarette policy debates. METHODS: This paper is the first to empirically analyse commercial actors' engagement in an e-cigarette policy consultation process and to examine their views on proposed regulation. It applies mixed methods, drawing on policy consultation submissions (n=32), semi-structured interviews (n=9) and a social network analysis of website links among 32 commercial actors. RESULTS: The results show that commercial actors' positions on e-cigarette regulation aligned with business interests. TTCs, independent e-cigarette manufacturers and other non-licensed commercial actors were opposed to most aspects of potential e-cigarette regulation (except for age of sale restrictions), whereas licensed commercial actors, including pharmaceutical companies, supported more stringent regulation. While collaboration was viewed as strategically important to gain policy influence, distinct commercial interests and concerns about TTC credibility led to strategic distancing and to collaboration being largely confined to sector boundaries. In addition to reiterating arguments employed by TTCs in previous regulatory debates, commercial actors focused on highlighting the technical complexity and harm reduction potential of e-cigarettes. CONCLUSION: Awareness of the various commercial interests and strategic positioning of commercial actors in e-cigarette policy should inform public health advocacy and policy development, including managing conflicts of interest in the context of Framework Convention on Tobacco Control Article 5.3.


Subject(s)
Electronic Nicotine Delivery Systems , Tobacco Industry , Tobacco Products , Health Policy , Humans , Policy , Scotland
2.
Radiat Meas ; 1472021 Sep.
Article in English | MEDLINE | ID: mdl-35669292

ABSTRACT

Organized by the European Radiation Dosimetry Group (EURADOS), a Monte Carlo code intercomparison exercise was conducted where participants simulated the emitted electron spectra and energy deposition around a single gold nanoparticle (GNP) irradiated by X-rays. In the exercise, the participants scored energy imparted in concentric spherical shells around a spherical volume filled with gold or water as well as the spectral distribution of electrons leaving the GNP. Initially, only the ratio of energy deposition with and without GNP was to be reported. During the evaluation of the exercise, however, the data for energy deposition in the presence and absence of the GNP were also requested. A GNP size of 50 nm and 100 nm diameter was considered as well as two different X-ray spectra (50 kVp and 100kVp). This introduced a redundancy that can be used to cross-validate the internal consistency of the simulation results. In this work, evaluation of the reported results is presented in terms of integral quantities that can be benchmarked against values obtained from physical properties of the radiation spectra and materials involved. The impact of different interaction cross-section datasets and their implementation in the different Monte Carlo codes is also discussed.

4.
Phys Med ; 69: 147-163, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31918367

ABSTRACT

PURPOSE: Targeted radiation therapy has seen an increased interest in the past decade. In vitro and in vivo experiments showed enhanced radiation doses due to gold nanoparticles (GNPs) to tumors in mice and demonstrated a high potential for clinical application. However, finding a functionalized molecular formulation for actively targeting GNPs in tumor cells is challenging. Furthermore, the enhanced energy deposition by secondary electrons around GNPs, particularly by short-ranged Auger electrons is difficult to measure. Computational models, such as Monte Carlo (MC) radiation transport codes, have been used to estimate the physical quantities and effects of GNPs. However, as these codes differ from one to another, the reliability of physical and dosimetric quantities needs to be established at cellular and molecular levels, so that the subsequent biological effects can be assessed quantitatively. METHODS: In this work, irradiation of single GNPs of 50 nm and 100 nm diameter by X-ray spectra generated by 50 and 100 peak kilovoltages was simulated for a defined geometry setup, by applying multiple MC codes in the EURADOS framework. RESULTS: The mean dose enhancement ratio of the first 10 nm-thick water shell around a 100 nm GNP ranges from 400 for 100 kVp X-rays to 600 for 50 kVp X-rays with large uncertainty factors up to 2.3. CONCLUSIONS: It is concluded that the absolute dose enhancement effects have large uncertainties and need an inter-code intercomparison for a high quality assurance; relative properties may be a better measure until more experimental data is available to constrain the models.


Subject(s)
Gold/chemistry , Metal Nanoparticles/chemistry , Radiotherapy/methods , Animals , Computer Simulation , Electrons , Humans , Imaging, Three-Dimensional , In Vitro Techniques , Mice , Monte Carlo Method , Neoplasms/diagnostic imaging , Quality Control , Radiometry , Reproducibility of Results , Water , X-Rays
5.
Radiat Prot Dosimetry ; 183(1-2): 11-16, 2019 May 01.
Article in English | MEDLINE | ID: mdl-30544197

ABSTRACT

Within EURADOS Working Group 6 'Computational Dosimetry', the micro and nanodosimetry task group 6.2 has recently conducted a Monte Carlo (MC) exercise open to participants around the world. The aim of this exercise is to quantify the contribution to the uncertainty of micro and nanodosimetric simulation results arising from the use of different electron-impact cross-sections, and hence physical models, employed by different MC codes (GEANT4-DNA, PENELOPE, MCNP6, FLUKA, NASIC and PHITS). Comparison of the participants' simulation results for both micro and nanodosimetric quantities using different MC codes was the first step of the exercise. The deviation between results is due to different cross-sections but also different tracking methods and particle transport cut-off energies. The second step of the exercise will involve using identical cross-section datasets to account only for the other variations in the first step, thus enabling the determination of the uncertainty contribution due to different cross-sections. This paper presents a comparison of the MC simulation results obtained in the first part of the exercise. For the microdosimetric simulations, particularly in the configuration where the electron source is contained within the micrometric target, the choice of MC code has a small influence on the results. For the nanodosimetric results, on the other hand, the mean ionisation cluster size distribution (ICSD) was sensitive to the physical models used in the MC codes. The ICSD was therefore chosen to study the influence of different cross-section data on the uncertainty of simulation results.


Subject(s)
Monte Carlo Method , Radiometry/methods , Uncertainty , Computer Simulation , Electrons , Europe , Iodine Radioisotopes , Models, Statistical , Models, Theoretical , Software
6.
Aust Vet J ; 92(6): 192-9, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24862997

ABSTRACT

OBJECTIVE: To measure the diagnostic performance of an Australian-developed ELISA for the detection of antibodies against the non-structural proteins (NSP) 3ABC of the foot and mouth disease (FMD) virus. DESIGN: Test development and validation study. METHODS: The diagnostic specificity was determined using 2535 sera from naïve animals and 1112 sera from vaccinated animals. Diagnostic sensitivity was calculated from the data for 995 sera from experimentally and field-infected animals from FMD-endemic countries in South East Asia. A commercial ELISA detecting antibodies against FMD virus NSP was used as the reference test to establish relative sensitivity and specificity. Bayesian latent class analysis was performed to corroborate results. The diagnostic window and rate of detection were determined at different times using sera from cattle, sheep and pigs before and after infection, and after vaccination and subsequent infection. Repeatability and reproducibility data were established. RESULTS: At 35% test cut-off, the 3ABC ELISA had an overall diagnostic sensitivity of 91.5% and diagnostic specificity of 96.4%. The diagnostic sensitivity in vaccinated and subsequently infected cattle was 68.4% and diagnostic specificity in vaccinated cattle was 98.0%. CONCLUSIONS: The 3ABC ELISA identified field and experimentally infected animals, as well as vaccinated and subsequently infected animals. Diagnostic sensitivity and specificity estimates for other FMD NSP tests are comparable with the results obtained in this study. This NSP ELISA was found to be 'fit for purpose' as a screening assay at the herd level to detect viral infection and also to substantiate absence of infection.


Subject(s)
Antibodies, Viral/blood , Enzyme-Linked Immunosorbent Assay/veterinary , Foot-and-Mouth Disease Virus/isolation & purification , Foot-and-Mouth Disease/diagnosis , Viral Nonstructural Proteins , Animals , Australia , Bayes Theorem , Cattle , Enzyme-Linked Immunosorbent Assay/methods , Foot-and-Mouth Disease/blood , Foot-and-Mouth Disease/prevention & control , Foot-and-Mouth Disease Virus/immunology , Sensitivity and Specificity , Sheep , Swine , Thailand , Vietnam , Viral Vaccines/immunology
8.
Health Place ; 16(5): 820-7, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20493757

ABSTRACT

Migrants after international relocation are confronted with various stressors that can challenge their adjustment capacities and lead to decreased health. Based on the analysis of qualitative interviews and focus groups, this article is the first to explore successful coping strategies of Polish migrants in Edinburgh, thereby providing insight into the coping process after economic migration across the European Union. The study reveals that Polish migrants are very resourceful in dealing with the stressors they face. It confirms the employment of various types of coping including problem-solving, emotion-regulating and appraisal-oriented strategies. Social support and appraisal emerge as important variables and are perceived to considerably influence the subsequent stages of the adjustment process. Based on the assumption that coping is likely to affect the health of migrant populations, a better understanding of coping followed by tailored support for international migrants might have a positive influence on public health, particularly in societies where international mobility and large migrant populations are common phenomena.


Subject(s)
Adaptation, Psychological , Stress, Psychological/ethnology , Transients and Migrants/psychology , Adolescent , Adult , Female , Humans , Male , Middle Aged , Poland/ethnology , Scotland , Stress, Psychological/etiology , Young Adult
9.
Radiat Prot Dosimetry ; 134(1): 13-22, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19395711

ABSTRACT

The usage of beta-radiation sources in various nuclear medicine therapies is increasing. Consequently, enhanced radiation protection measures are required, as medical staff more frequently handle high-activity sources required for therapy. Inhomogeneous radiation fields make it difficult to determine absorbed dose reliably. Routine monitoring with dosimeters does not guarantee any accurate determination of the local skin dose (LSD). In general, correction factors are used to correct for the measured dose and the maximum absorbed dose received. However, strong underestimations of the maximum exposure are possible depending on the individual handling the process and the reliability of dose measurements. Simulations can be used as a tool for a better understanding of the maximum possible exposure depending on the individual-related handling. While measurements reveal the overall dose during the entire irradiation time of the dosimeter, simulations help to analyse sequences of action. Hence, simulations allow for tracking the points of highest absorbed dose received during the handling process. In this respect, simulations were performed using the MCNPX software. In order to investigate the LSD, two hand phantoms were used, a model based on geometrical elements and a voxel hand. A typical situation of radiosynoviorthesis, i.e. handling a syringe filled with (90)Y, was simulated. The results of the simulations show that the annual dose limit may be exceeded within minutes at the position of maximum absorbed dose received and that finger-ring dosimeters measure significantly different doses depending on their wearing position. It is of essential importance to wear the dosimeter properly and to use suitable correction factors with respect to the individual. Simulations are a suitable tool for ensuring reliable dose determination and may help to derive recommendations regarding radiation protection measures.


Subject(s)
Beta Particles , Gamma Rays , Hand/radiation effects , Phantoms, Imaging , Radiation Protection , Software , Computer Simulation , Humans , Models, Anatomic , Monte Carlo Method , Radiation Dosage , Radiation Monitoring , Skin/radiation effects
12.
J Eval Clin Pract ; 14(3): 435-8, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18373574

ABSTRACT

RATIONALE: Current medical student perceptions of patient centredness and the priorities of students for a change in medical care were investigated. METHODS: We conducted an observational study using questionnaires at the University of Leipzig in Germany. In total, 188 consecutive medical students attending the Department of General Medicine participated in this study. We investigated students' priorities for an improvement in medical care related to aspects of the patient-doctor relationship and to aspects of organization. RESULTS: Receiving more information and undergoing the process of shared decision making was the most important choice; selected by 43.2% as their first priority. The second choice was found to be consultation time (16.2%) which also refers to the patient-doctor relationship. Shorter queues for tests, also considered important for more patient autonomy, were ranked third (14.6%). Medical students participating in this study were least interested in access to specialists, cost of medications and continuity of care. CONCLUSION: For the first time, it is shown that shared decision making, in addition to its many benefits, is not only a patients', but also a prospective doctors' top priority. Consequently, medical student training programmes might incorporate shared decision-making training as an important element of patient centredness.


Subject(s)
Decision Making , Patient Participation , Students, Medical/psychology , Adult , Attitude of Health Personnel , Female , Germany , Humans , Male , Physician-Patient Relations , Surveys and Questionnaires
14.
J Comp Pathol ; 136(4): 266-72, 2007 May.
Article in English | MEDLINE | ID: mdl-17498518

ABSTRACT

Seventeen grey-headed fruit bats (Pteropus poliocephalus) were inoculated subcutaneously with an isolate of Nipah virus derived from a fatally infected human. A control group of eight guinea-pigs was inoculated intraperitoneally with the same isolate in order to confirm virulence. Three of eight infected guinea-pigs developed clinical signs 7-9 days post-inoculation. Infected fruit bats developed a subclinical infection characterized by the transient presence of virus within selected viscera, episodic viral excretion and seroconversion. A range of histopathological changes was observed within the tissues of infected bats. Nipah virus was excreted in bat urine while neutralizing antibody was present in serum. This intermittent, low-level excretion of Nipah virus in the urine of bats may be sufficient to sustain the net reproductive value of the virus in a species where there is regular urine contamination of the fur, mutual grooming, and where urine droplets are a feature of the environment.


Subject(s)
Chiroptera/virology , Henipavirus Infections/pathology , Henipavirus Infections/transmission , Henipavirus Infections/veterinary , Urine/virology , Animals , Disease Reservoirs/virology , Guinea Pigs , Humans , Nipah Virus/isolation & purification , Nipah Virus/pathogenicity
15.
Radiat Prot Dosimetry ; 123(4): 464-72, 2007.
Article in English | MEDLINE | ID: mdl-17261536

ABSTRACT

The Forschungszentrum Karlsruhe operates a partial body counter, which is designed for the in vivo measurement of low-energy photon emitters in the human body. Recently, a numerical procedure has been developed which allows for the calculation of individual calibration factors for this partial body counter. The procedure is based on a Monte Carlo simulation of the radiation transport from the contaminated organ or tissue within the body to the detectors using the MCNP5 code. For simulation of the human body, the MEET Man dataset of the Institute of Biomedical Techniques of the University Karlsruhe has been applied. The derived calibration factors were compared with the respective values measured using some physical phantoms such as the Lawrence Livermore National Laboratory torso phantom and the bone phantoms of the New York University Medical Center and the US Transuranium and Uranium Registry.


Subject(s)
Calibration , Liver/radiation effects , Lung/radiation effects , Monte Carlo Method , Phantoms, Imaging , Photons , Radiation Monitoring/methods , Humans , Male , Radiation Monitoring/instrumentation
16.
J Comp Pathol ; 126(2-3): 124-36, 2002.
Article in English | MEDLINE | ID: mdl-11945001

ABSTRACT

A human isolate of Nipah virus from an outbreak of febrile encephalitis in Malaysia that coincided with a field outbreak of disease in pigs was used to infect eight 6-week-old pigs orally or subcutaneously and two cats oronasally. In pigs, the virus induced a respiratory and neurological syndrome consistent with that observed in the Malaysian pigs. Not all the pigs showed clinical signs, but Nipah virus was recovered from the nose and oropharynx of both clinically and sub-clinically infected animals. Natural infection of in-contact pigs, which was readily demonstrated, appeared to be acute and self-limiting. Subclinical infections occurred in both inoculated and in-contact pigs. Respiratory and neurological disease was also produced in the cats, with recovery of virus from urine as well as from the oropharynx. The clinical and pathological syndrome induced by Nipah virus in cats was comparable with that associated with Hendra virus infection in this species, except that in fatal infection with Nipah virus there was extensive inflammation of the respiratory epithelium, associated with the presence of viral antigen. Viral shedding via the nasopharynx, as observed in pigs and cats in the present study, was not a regular feature of earlier reports of experimental Hendra virus infection in cats and horses. The findings indicate the possibility of field transmission of Nipah virus between pigs via respiratory and oropharyngeal secretions.


Subject(s)
Cat Diseases/pathology , Paramyxoviridae Infections/veterinary , Paramyxovirinae/pathogenicity , Swine Diseases/pathology , Animals , Cat Diseases/immunology , Cat Diseases/virology , Cats , Female , Lung/pathology , Lung/virology , Nervous System Diseases/pathology , Nervous System Diseases/veterinary , Nervous System Diseases/virology , Neutralization Tests/veterinary , Paramyxoviridae Infections/immunology , Paramyxoviridae Infections/pathology , Paramyxovirinae/immunology , Paramyxovirinae/isolation & purification , Respiratory Mucosa/ultrastructure , Respiratory Mucosa/virology , Respiratory Tract Infections/pathology , Respiratory Tract Infections/veterinary , Respiratory Tract Infections/virology , Swine , Swine Diseases/immunology , Swine Diseases/virology , Trachea/pathology , Trachea/virology
17.
Aust Vet J ; 79(8): 559-62, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11599818

ABSTRACT

OBJECTIVE: To detect evidence of Ehrlichia canis infection of dogs from the major population centres of northern Australia, if present. DESIGN: Serological investigation for E. canis. PROCEDURE: The sera of 316 domestic dogs, collected from the northern Australian population centres of Townsville, Cairns, Darwin, Kununurra and Broome from May 1997 to August 1999, were investigated for evidence of infection with E. canis. Samples were tested for antibodies to E. canis using an indirect fluorescent antibody (IFA) test. The buffy coats from blood of dogs whose serum reacted in the IFA test were subsequently tested with a nested PCR to detect E. canis DNA. When available, blood from these dogs was injected into suckling mice, which were then examined for clinical disease and tested for the presence of E. canis antibodies. RESULTS: Of the 316 samples tested seven reacted in the IFA test for E. canis. None of the dogs from which these samples were obtained exhibited clinical signs of acute or chronic ehrlichiosis. The six positive samples available for testing were negative when tested with the nested PCR. Suckling mice inoculated with blood from three of the dogs whose serum was positive by IFA test showed no signs of clinical disease nor did their give positive reactions in the IFA test. CONCLUSIONS: No evidence of E. canis infection was confirmed in any of the dogs examined. Northern Australia would appear to remain free of this obligate parasite.


Subject(s)
Antibodies, Bacterial/blood , Dog Diseases/epidemiology , Ehrlichia/isolation & purification , Ehrlichiosis/veterinary , Animals , Australia/epidemiology , DNA, Bacterial/isolation & purification , Dog Diseases/blood , Dogs , Ehrlichiosis/epidemiology , Female , Fluorescent Antibody Technique, Indirect/veterinary , Male , Polymerase Chain Reaction/veterinary , Seroepidemiologic Studies , Urban Health
18.
Man Ther ; 6(3): 154-62, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11527455

ABSTRACT

Pain and muscular responses to a Neural Tissue Provocation Test with bias to median nerve were examined in 20 asymptomatic subjects. The test was performed on both arms with the cervical spine in a neutral position and in contralateral sideflexion as a sensitizing manoeuvre. The angle of elbow extension at the time of onset of pain and muscle activity in trapezius, biceps and triceps muscles was measured using an electrogoniometer. Muscle activity was recorded by surface electromyography. Results indicate that pain responses and muscle activity of trapezius are present in the majority of normal subjects. The onset of pain was highly reliable and compared favourably with detection of muscle activity onset. There was no significant difference of the angle of the elbow with the onset of pain between arms. Hence in patients with unilateral neck or upper limb pain a difference between sides might be indicative of a possible neural tissue involvement. Pain and muscular responses were influenced by the position of the cervical spine. This finding suggests that cervical contralateral sideflexion has a sensitizing effect on neural tissues. There was an association between the onset of pain and onset of trapezius muscle activity in all painful trials. However, muscle activity was also present in subjects with no pain.


Subject(s)
Arm/innervation , Cervical Vertebrae/innervation , Diagnostic Techniques, Neurological , Median Nerve/physiology , Adult , Analysis of Variance , Female , Humans , Male , Pain/physiopathology , Reproducibility of Results
19.
Emerg Infect Dis ; 7(3): 439-41, 2001.
Article in English | MEDLINE | ID: mdl-11384522

ABSTRACT

Nipah virus, family Paramyxoviridae, caused disease in pigs and humans in peninsular Malaysia in 1998-99. Because Nipah virus appears closely related to Hendra virus, wildlife surveillance focused primarily on pteropid bats (suborder Megachiroptera), a natural host of Hendra virus in Australia. We collected 324 bats from 14 species on peninsular Malaysia. Neutralizing antibodies to Nipah virus were demonstrated in five species, suggesting widespread infection in bat populations in peninsular Malaysia.


Subject(s)
Chiroptera/virology , Paramyxoviridae Infections/veterinary , Paramyxovirinae/isolation & purification , Animals , Antibodies, Viral/blood , Malaysia , Seroepidemiologic Studies
20.
Vaccine ; 19(27): 3752-8, 2001 Jun 14.
Article in English | MEDLINE | ID: mdl-11395210

ABSTRACT

Five week old, commercially available large white pigs were vaccinated with either a single dose or two doses of a recombinant porcine adenovirus expressing the glycoprotein D gene from pseudorabies virus (PRV). Pigs were monitored for the development of serum neutralizing antibodies to PRV and challenged 3 weeks after final vaccination. Prior to challenge, pigs given 2 doses of the vaccine demonstrated boosted levels of antibody compared with those given a single dose, and all surviving pigs had increased neutralization titres over pre-challenge levels. Following challenge, pigs were monitored for clinical signs of disease, with blood and nasal swabs collected for virus isolation. All control animals became sick with elevated temperatures for 6 days post challenge, whereas; vaccinated animals displayed an increase in body temperature for only 2-3 days. Control pigs and those given a single dose all lost condition, but the group given 2 doses remained healthy. At postmortem, gross lesions of pneumonia only occurred in control animals and those given a single dose of vaccine. Histology carried out on the brains of all animals demonstrated a difference in severity of infection and frequency of immunohistochemical antigen detection between test animals, with control and single dose groups being most severely affected and pigs given 2 doses the least. Virus isolation studies demonstrated that no viraemia could be detected, but virus was found in nasal swabs from some animals in both groups of vaccinates following challenge.


Subject(s)
Adenoviridae/genetics , Herpesvirus 1, Suid/genetics , Herpesvirus 1, Suid/immunology , Pseudorabies Vaccines/therapeutic use , Pseudorabies/prevention & control , Vaccines, DNA/therapeutic use , Viral Envelope Proteins/genetics , Adenoviridae/immunology , Animals , Antibodies, Viral/blood , Cell Line , Herpesvirus 1, Suid/isolation & purification , Immunization Schedule , Neutralization Tests , Pseudorabies/mortality , Pseudorabies/pathology , Pseudorabies Vaccines/genetics , Swine , Viral Envelope Proteins/biosynthesis , Viral Envelope Proteins/immunology
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