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1.
Philos Trans R Soc Lond B Biol Sci ; 379(1903): 20220315, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38643788

RESUMO

Values play a significant role in decision-making, especially regarding nature. Decisions impact people and nature in complex ways and understanding which values are prioritised, and which are left out is an important task for improving the equity and effectiveness of decision-making. Based on work done for the IPBES Values Assessment, this paper develops a framework to support analyses of how decision-making influences nature as well as whose values get prioritised. The framework is used to analyse key areas of environmental policy: a) the present model for nature protection in market economies, b) the role of valuation in bringing nature values into decisions, and c) values embedded in environmental policy instruments, exemplified by protected areas for nature conservation and payments for ecosystem services. The analyses show that environmental policies have been established as mere additions to decision-making structures that foster economic expansion, which undermines a wide range of nature's values. Moreover, environmental policies themselves are also focused on a limited set of nature's diverse values. This article is part of the theme issue 'Bringing nature into decision-making'.


Assuntos
Conservação dos Recursos Naturais , Tomada de Decisões , Conservação dos Recursos Naturais/métodos , Política Ambiental , Humanos , Ecossistema , Natureza , Valores Sociais
2.
Cardiol Res Pract ; 2023: 2111843, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37426448

RESUMO

Introduction: Recent national guidelines recommending mitral valve replacement (MVR) for severe secondary mitral regurgitation have resulted in an increased utilization of mitral bioprosthesis. There is a paucity of data on how longitudinal clinical outcomes vary by prosthesis type. We examined long-term survival and risk of reoperation between patients having bovine vs. porcine MVR. Study Design. A retrospective analysis of MVR or MVR + coronary artery bypass graft (CABG) from 2001 to 2017 among seven hospitals reporting to a prospectively maintained clinical registry was conducted. The analytic cohort included 1,284 patients undergoing MVR (801 bovine and 483 porcine). Baseline comorbidities were balanced using 1 : 1 propensity score matching with 432 patients in each group. The primary end point was all-cause mortality. Secondary end points included in-hospital morbidity, 30-day mortality, length of stay, and risk of reoperation. Results: In the overall cohort, patients receiving porcine valves were more likely to have diabetes (19% bovine vs. 29% porcine; p < 0.001), COPD (20% bovine vs. 27% porcine; p=0.008), dialysis or creatinine >2 mg/dL (4% bovine vs. 7% porcine; p=0.03), and coronary artery disease (65% bovine vs. 77% porcine; p < 0.001). There was no difference in stroke, acute kidney injury, mediastinitis, pneumonia, length of stay, in-hospital morbidity, or 30-day mortality. In the overall cohort, there was a difference in long-term survival (porcine HR 1.17 (95% CI: 1.00-1.37; p=050)). However, there was no difference in reoperation (porcine HR 0.56 (95% CI: 0.23-1.32; p=0.185)). In the propensity-matched cohort, patients were matched on all baseline characteristics. There was no difference in postoperative complications or in-hospital morbidity and 30-day mortality. After 1 : 1 propensity score matching, there was no difference in long-term survival (porcine HR 0.97 (95% CI: 0.81-1.17; p=0.756)) or risk of reoperation (porcine HR 0.54 (95% CI: 0.20-1.47; p=0.225)). Conclusions: In this multicenter analysis of patients undergoing bioprosthetic MVR, there was no difference in perioperative complications and risk of reoperation of long-term survival after matching.

3.
Vaccine ; 40(13): 1932-1947, 2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35227520

RESUMO

INTRODUCTION: Invasive meningococcal disease (IMD) is a notifiable disease in Germany and other European countries. Due to the high lethality of the disease and the risk of long-term consequences, IMD prevention is of high public health relevance despite the low number of cases in the population. This study aims to describe key epidemiological and economic parameters of IMD in Germany to support national decision-making processes for implementing enhanced prevention measures. METHODS: Based on a systematic literature review in PubMed and EMBASE, all publications on the burden of disease and costs of IMD published up to May 2020 were evaluated. Additionally, notification data were used to report the annual case numbers and incidence of IMD in Germany until the end of 2019. RESULTS: Thirty-six studies were included, of which 35 reported data on the epidemiological burden of disease and three reported data on economic aspects of IMD. The type of reported endpoints and results on the incidence of IMD differed widely by reporting year, population, and data source used. Most of the data are reported without specific information about a serogroup. Data on the economic burden of disease and healthcare resource use are scarce. Based on mandatory notification data, a decrease in the incidence of notified IMD cases has been observed since 2004. Currently, the nationwide annual incidence in Germany is at 0.3 cases per 100,000 persons and has gradually decreased. While the overall decline is mainly attributable to MenB, cases with MenY and MenW are the only ones that have increased on a low level in recent years. CONCLUSION: While IMD is a rare disease, high direct and indirect costs illustrate the relevance of the disease for patients, caregivers, as well as for the health care system. Future research should concentrate on quantifying the long-term economic burden and indirect costs of meningococcal disease. Integrated IMD surveillance with isolate characterisation remains crucial to inform public health policies.


Assuntos
Infecções Meningocócicas , Vacinas Meningocócicas , Neisseria meningitidis , Estresse Financeiro , Alemanha/epidemiologia , Humanos , Incidência , Infecções Meningocócicas/epidemiologia , Infecções Meningocócicas/prevenção & controle , Sorogrupo
4.
PLoS One ; 17(3): e0264458, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35294466

RESUMO

As people, animals and materials are transported across increasingly large distances in a globalized world, threats to our biosecurity and food security are rising. Aotearoa New Zealand is an island nation with many endemic species, a strong local agricultural industry, and a need to protect these from pest threats, as well as the economy from fraudulent commodities. Mitigation of such threats is much more effective if their origins and pathways for entry are understood. We propose that this may be addressed in Aotearoa using strontium isotope analysis of both pests and products. Bioavailable radiogenic isotopes of strontium are ubiquitous markers of provenance that are increasingly used to trace the origin of animals and plants as well as products, but currently a baseline map across Aotearoa is lacking, preventing use of this technique. Here, we have improved an existing methodology to develop a regional bioavailable strontium isoscape using the best available geospatial datasets for Aotearoa. The isoscape explains 53% of the variation (R2 = 0.53 and RMSE = 0.00098) across the region, for which the primary drivers are the underlying geology, soil pH, and aerosol deposition (dust and sea salt). We tested the potential of this model to determine the origin of cow milk produced across Aotearoa. Predictions for cow milk (n = 33) highlighted all potential origin locations that share similar 87Sr/86Sr values, with the closest predictions averaging 7.05 km away from their true place of origin. These results demonstrate that this bioavailable strontium isoscape is effective for tracing locally produced agricultural products in Aotearoa. Accordingly, it could be used to certify the origin of Aotearoa's products, while also helping to determine if new pest detections were of locally breeding populations or not, or to raise awareness of imported illegal agricultural products.


Assuntos
Isótopos de Estrôncio , Estrôncio , Animais , Biosseguridade , Humanos , Nova Zelândia , Estrôncio/análise , Isótopos de Estrôncio/análise
5.
Appl Opt ; 60(19): D43-D51, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34263827

RESUMO

We present the inscription of narrow-linewidth fiber Bragg gratings (FBGs) into different types of multicore fibers (MCFs) using ultrashort laser pulses and the phase mask technique, which can act as notch filters. Such filters are required, e.g., to suppress light emitted by hydroxyl in the Earth's upper atmosphere, which disturbs ground-based observation of extraterrestrial objects in the near infrared. However, the inscription into a commercially available seven-core fiber showed a quite large core-to-core deviation of the resonance wavelength of up to 0.45 nm. Two options are presented to overcome this: first, we present the photo-treatment of the FBGs to tune the resonance wavelength, which allows for sufficient resonance shifts. Second, adapted MCFs containing 12 cores, arranged on a circle, are fabricated. For this, two different fabrication procedures were investigated, namely, the mechanical drilling of the preform for a rod-in-tube version as well as a stack-and-draw approach. Both adapted MCFs yielded significant improvements with core-to-core wavelength variations of the FBGs of only about 0.18 nm and 0.11 nm, respectively, sufficient to fulfill the requirements for astronomical filter applications as discussed above.

6.
Opt Express ; 28(24): 35682-35694, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33379679

RESUMO

We present an innovative concept of a semi-aperiodic phase mask design that enables the realization of multi-notch fiber Bragg gratings (FBG). This design utilizes the overlap and interference of near-infrared ultrashort laser pulses diffracted by short sequenced phase mask sections, which not only allows for a highly stable and reproducible inscription of a large number of wavelength filters but also paves the way towards full aperiodic phase masks. The semi-aperiodic FBG inscribed by this phase mask enables versatile notch filters showing multiple non-equidistant resonances. Those filters target applications, for instance in ground-based telescopes, where a large number of hydroxyl emission lines emitted in the upper atmosphere at near-infrared wavelengths restrict the observation of faint extraterrestrial objects.

7.
Sci Rep ; 10(1): 3944, 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32109240

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

8.
Eur J Cancer ; 118: 82-90, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31326730

RESUMO

BACKGROUND: Coagulation activation is a hallmark of cancer, and anticoagulants have shown tumour-inhibiting properties. However, recent trials have failed to demonstrate improved survival with low-molecular-weight heparin (LMWH) in cancer populations. This has raised the question of suboptimal adherence as a possible explanation for the lack of benefit. Still, there is no standardised method to directly monitor LMWH in patient plasma. Here, we directly determine LMWH levels in patients using the Heparin Red assay to objectively assess adherence and how this associates with the patient outcome in the RASTEN trial. METHODS: RASTEN is a multicentre, randomised phase III trial investigating if the addition of LMWH to standard therapy can improve survival in small-cell lung cancer. LMWH was measured in plasma (N = 258) by the Heparin Red assay and compared with the anti-factor Xa (anti-FXa) activity assay. RESULTS: Both methods could differentiate patients in the LMWH arm from the control arm and patients receiving therapeutic LMWH owing to thrombosis. Receiver Operating Characteristic (ROC) analysis yielded adherence rates of 85% for anti-FXa and 68% for Heparin Red. No survival benefits were found in the adherent subgroup compared with the control arm (hazard ratio [HR]: 1.26; 95% confidence interval [CI]: 0.95-1.67; P = 0.105 and HR: 1.19; 95% CI: 0.89-1.60; P = 0.248 for anti-FXa and Heparin Red, respectively). Heparin Red could define patients with high probability of adherence to LMWH treatment, which warrants prospective studies for further validation. Our finding that the LMWH-adherent subpopulation did not show improved survival excludes that the negative outcome of RASTEN was due to poor adherence.


Assuntos
Anticoagulantes/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Coagulação Sanguínea/efeitos dos fármacos , Enoxaparina/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Adesão à Medicação , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Trombose/tratamento farmacológico , Idoso , Anticoagulantes/efeitos adversos , Anticoagulantes/sangue , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Testes de Coagulação Sanguínea , Monitoramento de Medicamentos , Enoxaparina/efeitos adversos , Enoxaparina/sangue , Feminino , Humanos , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Carcinoma de Pequenas Células do Pulmão/sangue , Carcinoma de Pequenas Células do Pulmão/mortalidade , Suécia , Trombose/sangue , Trombose/mortalidade , Fatores de Tempo , Resultado do Tratamento
9.
Sci Rep ; 9(1): 3659, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30842502

RESUMO

Superconductors are well known for their ability to screen out magnetic fields. In type-II superconductors, as the magnetic field pressure is progressively increased, magnetic flux accumulates at the periphery of the sample, very much like charges accumulate in a capacitor when voltage is increased. As for capacitors, exceeding certain threshold field causes the blocked magnetic flux to abruptly penetrate into the sample. This phenomenon, triggered by a thermomagnetic instability, is somewhat analogous to the dielectric breakdown of the capacitor and leaves behind a similar Lichtenberg imprinting. Even though electrical breakdown threshold has been extensively studied in dielectrics, little information is known about the statistical distribution of the thermomagnetic breakdown in superconductors. In this work, we address this problem by performing magneto-optical imaging experiments on a Nb film where nanometric heating elements are used to rapidly erase the magnetic history of the sample. We demonstrate that the size and shape distributions of avalanches permits to unambiguously identify the transition between two regimes where either thermal diffusivity or magnetic diffusivity dominates. Clear criteria for discriminating athermal dynamic avalanches from thermally driven avalanches are introduced. This allows us to provide the first precise determination of the threshold field of the thermomagnetic breakdown and unveil the details of the transition from finger-like magnetic burst to dendritic branching morphology. These findings open a new avenue in the interdisciplinary exploration of catastrophic avalanches through non destructive repeatable experiments.

10.
Biomed Phys Eng Express ; 6(1): 015009, 2019 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-33438597

RESUMO

Recent epidemiological studies suggested to lower the threshold dose for radiation induced cataract in the eye lens. Therefore, eye lens radiation protection became to play a more important role in personal dosimetry. The main objective of this work is to propose a new methodology for prototyping and benchmarking of an eye lens dosimter based on the equivalent dose to the sensitive part of the eye lens, using CAD Software and Geant4 Monte Carlo simulations with mesh modelling and 3D printing. A 3D printed dosemeter was type tested based on IEC 62387:2012, in terms of energy and angular dependence for the measurements of Hp(3). The results show that the methodology employed is suitable for the development of new eye lens dosemeters.


Assuntos
Cristalino/efeitos da radiação , Impressão Tridimensional , Algoritmos , Simulação por Computador , Humanos , Método de Monte Carlo , Doses de Radiação , Monitoramento de Radiação/métodos , Proteção Radiológica/métodos
11.
Rev Sci Instrum ; 89(2): 023705, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29495853

RESUMO

We present a detailed quantitative magneto-optical imaging study of several superconductor/ferromagnet hybrid structures, including Nb deposited on top of thermomagnetically patterned NdFeB and permalloy/niobium with erasable and tailored magnetic landscapes imprinted in the permalloy layer. The magneto-optical imaging data are complemented with and compared to scanning Hall probe microscopy measurements. Comprehensive protocols have been developed for calibrating, testing, and converting Faraday rotation data to magnetic field maps. Applied to the acquired data, they reveal the comparatively weaker magnetic response of the superconductor from the background of larger fields and field gradients generated by the magnetic layer.

12.
Geophys Res Lett ; 45(21): 12023-12031, 2018 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-30686845

RESUMO

Rapid adjustments are responses to forcing agents that cause a perturbation to the top of atmosphere energy budget but are uncoupled to changes in surface warming. Different mechanisms are responsible for these adjustments for a variety of climate drivers. These remain to be quantified in detail. It is shown that rapid adjustments reduce the effective radiative forcing (ERF) of black carbon by half of the instantaneous forcing, but for CO2 forcing, rapid adjustments increase ERF. Competing tropospheric adjustments for CO2 forcing are individually significant but sum to zero, such that the ERF equals the stratospherically adjusted radiative forcing, but this is not true for other forcing agents. Additional experiments of increase in the solar constant and increase in CH4 are used to show that a key factor of the rapid adjustment for an individual climate driver is changes in temperature in the upper troposphere and lower stratosphere.

13.
Psychol Med ; 48(3): 508-518, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28735596

RESUMO

BACKGROUND: Aberrant reward mechanisms with regard to slim body shapes are discussed in patients with anorexia nervosa (AN). The aim of the present study was to examine of cue reactivity toward body shapes in AN via the late positive potential (LPP), an event-related electroencephalography (EEG) component. By including adolescents and adults, aspects of development and chronification could be studied (2 × 2 design). METHODS: Thirty-two female AN patients (19 adolescents and 13 adults) and 37 control participants (16 adolescents and 21 adults) were included. Standardized photographic stimuli showing women's bodies in underwear from five body mass index (BMI) categories (extremely underweight to extremely overweight) were presented. During picture evaluation, EEG activity was recorded (10-20 system). The LPP was measured in two time windows characterized by different topographies (450-700 ms: posterior; 1000-1300 ms: central). RESULTS: Regarding the posterior component, LPP amplitudes were clearly reduced in adult but not in adolescent patients; for both time windows the LPP showed differential patterns over BMI categories for patients and controls. Regarding the central component, a highly significant linear decrease from extremely underweight to extremely overweight body shapes was revealed in patients and no significant modulation in control participants. CONCLUSIONS: Adolescent and adult patients show increased sustained attention toward extremely underweight bodies. In chronically ill patients, this bias appears to be accompanied by generally reduced automatic attention. The LPP findings provide a differentiated picture of aberrant cue reactivity which could be interpreted as motivated attention toward body shapes in AN.


Assuntos
Anorexia Nervosa/psicologia , Sinais (Psicologia) , Sobrepeso/psicologia , Magreza/psicologia , Adolescente , Adulto , Anorexia Nervosa/diagnóstico , Índice de Massa Corporal , Estudos de Casos e Controles , Criança , Depressão/psicologia , Eletroencefalografia , Feminino , Humanos , Motivação , Adulto Jovem
14.
Geophys Res Lett ; 45(20): 11399-11405, 2018 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-30774164

RESUMO

Different climate drivers influence precipitation in different ways. Here we use radiative kernels to understand the influence of rapid adjustment processes on precipitation in climate models. Rapid adjustments are generally triggered by the initial heating or cooling of the atmosphere from an external climate driver. For precipitation changes, rapid adjustments due to changes in temperature, water vapor, and clouds are most important. In this study we have investigated five climate drivers (CO2, CH4, solar irradiance, black carbon, and sulfate aerosols). The fast precipitation responses to a doubling of CO2 and a 10-fold increase in black carbon are found to be similar, despite very different instantaneous changes in the radiative cooling, individual rapid adjustments, and sensible heating. The model diversity in rapid adjustments is smaller for the experiment involving an increase in the solar irradiance compared to the other climate driver perturbations, and this is also seen in the precipitation changes.

15.
Philos Trans R Soc Lond B Biol Sci ; 372(1722)2017 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-28438919

RESUMO

Several recent initiatives such as Planetary Health, EcoHealth and One Health claim that human health depends on flourishing natural ecosystems. However, little has been said about the operational and implementation challenges of health-oriented conservation actions on the ground. We contend that ecological-epidemiological research must be complemented by a form of implementation science that examines: (i) the links between specific conservation actions and the resulting ecological changes, and (ii) how this ecological change impacts human health and well-being, when human behaviours are considered. Drawing on the policy evaluation tradition in public economics, first, we present three examples of recent social science research on conservation interventions that affect human health. These examples are from low- and middle-income countries in the tropics and subtropics. Second, drawing on these examples, we present three propositions related to impact evaluation and non-market valuation that can help guide future multidisciplinary research on conservation and human health. Research guided by these propositions will allow stakeholders to determine how ecosystem-mediated strategies for health promotion compare with more conventional biomedical prevention and treatment strategies for safeguarding health.This article is part of the themed issue 'Conservation, biodiversity and infectious disease: scientific evidence and policy implications'.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Saúde Ambiental , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/legislação & jurisprudência , Saúde Ambiental/economia , Saúde Ambiental/legislação & jurisprudência , Humanos
16.
Adv Cancer Res ; 133: 23-50, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28052820

RESUMO

The significantly higher breast cancer (BCa) mortality rates of African-American (AA) women compared to non-Hispanic (NHW) white women constitute a major US health disparity. Investigations have primarily focused on biological differences in tumors to explain more aggressive forms of BCa in AA women. The biology of tumors cannot be modified, yet lifestyle changes can mitigate their progression and recurrence. AA communities have higher percentages of obesity than NHWs and exhibit inefficient access to care, low socioeconomic status, and reduced education levels. Such factors are associated with limited healthy food options and sedentary activity. AA women have the highest prevalence of obesity than any other racial/ethnic/gender group in the United States. The social ecological model (SEM) is a conceptual framework on which interventions could be developed to reduce obesity. The SEM includes intrapersonal factors, interpersonal factors, organizational relationships, and community/institutional policies that are more effective in behavior modification than isolation from the participants' environmental context. Implementation of SEM-based interventions in AA communities could positively modify lifestyle behaviors, which could also serve as a powerful tool in reducing risk of BCa, BCa progression, and BCa recurrence in populations of AA women.


Assuntos
Neoplasias da Mama/mortalidade , Etnicidade/estatística & dados numéricos , Exercício Físico , Disparidades nos Níveis de Saúde , Atividade Motora/fisiologia , Obesidade/complicações , Neoplasias da Mama/etiologia , Feminino , Humanos , Taxa de Sobrevida
17.
Phys Med Biol ; 62(3): 781-809, 2017 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-28072578

RESUMO

The purpose of bowtie filters in CT scanners is to homogenize the x-ray intensity measured by the detectors in order to improve the image quality and at the same time to reduce the dose to the patient because of the preferential filtering near the periphery of the fan beam. For CT dosimetry, especially for Monte Carlo calculations of organ and tissue absorbed doses to patients, it is important to take the effect of bowtie filters into account. However, material composition and dimensions of these filters are proprietary. Consequently, a method for bowtie filter simulation independent of access to proprietary data and/or to a specific scanner would be of interest to many researchers involved in CT dosimetry. This study presents such a method based on the weighted computer tomography dose index, CTDIw, defined in two cylindrical PMMA phantoms of 16 cm and 32 cm diameter. With an EGSnrc-based Monte Carlo (MC) code, ratios CTDIw/CTDI100,a were calculated for a specific CT scanner using PMMA bowtie filter models based on sigmoid Boltzmann functions combined with a scanner filter factor (SFF) which is modified during calculations until the calculated MC CTDIw/CTDI100,a matches ratios CTDIw/CTDI100,a, determined by measurements or found in publications for that specific scanner. Once the scanner-specific value for an SFF has been found, the bowtie filter algorithm can be used in any MC code to perform CT dosimetry for that specific scanner. The bowtie filter model proposed here was validated for CTDIw/CTDI100,a considering 11 different CT scanners and for CTDI100,c, CTDI100,p and their ratio considering 4 different CT scanners. Additionally, comparisons were made for lateral dose profiles free in air and using computational anthropomorphic phantoms. CTDIw/CTDI100,a determined with this new method agreed on average within 0.89% (max. 3.4%) and 1.64% (max. 4.5%) with corresponding data published by CTDosimetry (www.impactscan.org) for the CTDI HEAD and BODY phantoms, respectively. Comparison with results calculated using proprietary data for the PHILIPS Brilliance 64 scanner showed agreement on average within 2.5% (max. 5.8%) and with data measured for that scanner within 2.1% (max. 3.7%). Ratios of CTDI100,c/CTDI100, p for this study and corresponding data published by CTDosimetry (www.impactscan.org) agree on average within about 11% (max. 28.6%). Lateral dose profiles calculated with the proposed bowtie filter and with proprietary data agreed within 2% (max. 5.9%), and both calculated data agreed within 5.4% (max. 11.2%) with measured results. Application of the proposed bowtie filter and of the exactly modelled filter to human phantom Monte Carlo calculations show agreement on the average within less than 5% (max. 7.9%) for organ and tissue absorbed doses.


Assuntos
Filtração/métodos , Modelos Teóricos , Método de Monte Carlo , Imagens de Fantasmas , Tomógrafos Computadorizados/normas , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Filtração/instrumentação , Humanos , Doses de Radiação
18.
Rev Sci Instrum ; 87(11): 113702, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910624

RESUMO

We present a scanning Hall probe microscope operating in ambient conditions. One of the unique features of this microscope is the use of the same stepper motors for both sample positioning as well as scanning, which makes it possible to have a large scan range (few mm) in the x and y directions, with a scan resolution of 0.1 µm. Protocols have been implemented to enable scanning at different heights from the sample surface. The z range is 35 mm. Microstructured Hall probes of size 1-5 µm have been developed. A minimum probe-sample distance <2 µm has been obtained by the combination of new Hall probes and probe-sample distance regulation using a tuning fork based force detection technique. The system is also capable of recording local B(z) profiles. We discuss the application of the microscope for the study of micro-magnet arrays being developed for applications in micro-systems.


Assuntos
Campos Magnéticos , Microscopia de Varredura por Sonda/métodos , Modelos Teóricos , Microscopia de Varredura por Sonda/instrumentação
19.
Chirurg ; 87(9): 775-784, 2016 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-27356924

RESUMO

BACKGROUND: The medical dissertation represents an independently processed scientific project. In the field of medicine this has for many years displayed the basis for controversial discussions. The aim of the study presented here was to evaluate the prerequisites of all current promotion regulations in German medical faculties in order to develop a comparability on the basis of a scoring system. METHOD: An independent analysis of all promotion regulations from German medical faculties for the year 2014 was carried out according to 12 primary outcome measures and a scoring system. RESULTS: The average total score of promotion regulations at 37 German medical faculties was 57.2 points (SD ±9.5) out of a possible 100 scoring points. The highest scores with 72-85 points were achieved by 3 faculties and 5 achieved scores of only 42-45 points. The range of the different criteria tested was broad. While the written thesis, the review process, the examination requirements as well as the grading of the thesis were defined in all regulations, the introduction into good clinical practice, knowledge of methodology as well as a check for plagiarism only seem to play minor roles. CONCLUSION: The promotion regulations at German medical faculties show a great variation using the scoring system presented here for the first time. Standardized federal promotion regulations might help to establish a structured transparency as well as a national equality of opportunity.


Assuntos
Dissertações Acadêmicas como Assunto , Desempenho Acadêmico , Educação Médica , Docentes de Medicina , Alemanha , Humanos
20.
J Radiol Prot ; 36(2): 246-54, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27025551

RESUMO

The aim of this study was to evaluate the radiation doses to patients and staff received from the first cases of prostatic artery embolization (PAE) conducted in a public hospital in Recife, Brazil. Five PAE procedures for 5 men diagnosed with benign prostatic hyperplasia were investigated. In order to characterize patient exposure, dosimetric quantities, such as the air kerma-area product (P KA), the cumulative air kerma at the interventional reference point (Ka,r), the number of images, etc, were registered. To evaluate the possibility for deterministic effects, the peak skin dose (PSD) was measured using radiochromic films. For evaluation of personal dose equivalent and effective dose to the medical staff, thermoluminescent dosemeters (TLD-100) were used. The effective dose was estimated using the double dosimetry alghoritm of von Boetticher. The results showed that the mean patient's PSD per procedure was 2674.2 mGy. With regard to the medical staff, the mean, minimum and maximum effective doses estimated per procedure were: 18 µSv, 12 µSv and 21 µSv respectively. High personal equivalent doses were found for the feet, hands and lens of the eye, due to the use of multiple left anterior oblique projections and the improper use of the suspended lead screen and the lead curtain during procedures.


Assuntos
Embolização Terapêutica , Próstata/irrigação sanguínea , Hiperplasia Prostática/terapia , Exposição à Radiação , Radiografia Intervencionista , Brasil , Humanos , Masculino , Exposição Ocupacional , Doses de Radiação , Proteção Radiológica , Radiometria , Pele/efeitos da radiação , Dosimetria Termoluminescente
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