Laboratory characterisation of the radiation temperature error of radiosondes and its application to the GRUAN data processing for the Vaisala RS41

The paper presents the Simulator for Investigation of Solar Temperature Error of Radiosondes (SISTER), a setup that was developed to quantify the solar heating of the temperature sensor of radiosondes under laboratory conditions by recreating as closely as possible the atmospheric and illumination conditions that are encountered during a daytime radiosounding ascent. SISTER controls the pressure (3 hPa to 1020 hPa) and ventilation speed of the air inside the windtunnel-like setup to simulate the conditions between the surface and 35 km altitude, to determine the dependence of the radiation temperature error on the irradiance and the convective cooling. The radiosonde is mounted inside a quartz tube, while the complete sensor boom is illuminated by an external light source to include the conductive heat transfer between sensor and boom. A special feature of SISTER is that the radiosonde is rotated around its axis to imitate the spinning of the radiosonde in flight. The characterisation of the radiation temperature error is performed for various pressures, ventilation speeds and illumination angles, yielding a 2D-parameterisation of the radiation error for each illumination angle, with an uncertainty smaller than 0.2 K (k = 2) for typical ascend speeds. This parameterisation is applied in the GRUAN processing for radiosonde data, which relies on the extensive characterisation of the sensor properties to produce a traceable reference data product which is free of manufacturer dependent effects. The GRUAN radiation correction model combines the laboratory characterisation with model calculations of the actual radiation field during the sounding to estimate the correction profile. In the second part of this paper it is described how this procedure was applied in the development of the GRUAN data product for the Vaisala RS41 radiosonde (version 1, RS41-GDP.1). The magnitude of the averaged correction profile increases gradually from 0.1 K at the surface to approximately 0.8 K at 35 km altitude. Comparison between sounding data (N = 154) that were GRUAN-processed and Vaisala-processed reveal that the daytime differences are smaller than +0.1 K (GRUAN – Vaisala) in the troposphere and increase above the tropopause steadily with altitude to +0.35 K (GRUAN – Vaisala) at 35 km. These differences are just within the limits of the combined uncertainties (with coverage factor k = 2) of both data products, meaning that the GRUAN processing and the Vaisala processing are in agreement.

Predictability of Elimination and Excretion of Small Molecules from Animals to Humans, and Impact on Dosimetry for human ADME Studies with Radiolabeled Drugs

Background: We assessed the extent to which urinary and fecal excretion of 14C-labeled drug material in animal ADME studies was predictive of human ADME studies. We compared observed plasma elimination half lives for total drug related radioactivity in humans to pre-study predictions, and we estimated the impact of any major differences on human dosimetry calculations. Methods: We included 34 human ADME studies with doses of 14C above 0.1 MBq. We calculated ratios of dosimetry input parameters (percentage fecal excretion in humans versus animals; observed half life in humans versus predicted pre-study) and output parameters (effective dose post-study versus pre study) and assessed their relationship. Results: A quantitative correlation assessment did not show a statistically significant correlation between the ratios of percentages of 14C excreted in feces and the ratios of dosimetry outcomes in the entire dataset, but a statistically significant correlation was found when assessing the studies that were based on ICRP 60/62 (n=19 studies; P=0.0028). There also appeared to be a correlation between the plasma half-life ratios and the ratios of dosimetry results. A quantitative correlation assessment showed that there was a statistically significant correlation between these ratios (P<0.0001). Conclusion: In all cases where the plasma elimination half-life for 14C in humans was found to be longer than the predicted value, the radiation burden was still within ICRP Category IIa. Containment of the actual radiation burden below the limit of 1.00 mSv appeared to be determined partly also by our choice to limit 14C doses to 3.7 MBq.

Модели плоской электромагнитной волны

Показано, что вывод о существовании плоской электромагнитной волны поперечного типа, как следствие из уравнений Максвелла, является не корректным. Реальное излучение от антенны можно объяснить, если оно формируется фотонами, не имеющими волновых свойств. Abstract. It is shown that the conclusion about the existence of a plane electromagnetic wave of a transverse type, as a consequence of the Maxwell equations, is not correct. The actual radiation from the antenna can be explained if it is formed by Photons that do not have wave properties.

Optimal cumulative dose of cisplatin for concurrent chemoradiotherapy among patients with locally advanced nasopharyngeal carcinoma: a multicenter analysis in Thailand

IntroductionChemoradiotherapy (CRT) with high cumulative doses (CDs) of cisplatin has been considered the standard of care for locally advanced nasopharyngeal carcinoma (LA-NPC). However, given most patients’ inability to tolerate high CDs due to cisplatin-related toxicities, the optimal CD of cisplatin during CRT remains undetermined.MethodsPatients with LA-NPC who received CRT with cisplatin between 2007 and 2017 were identified through the Thai head and neck cancer multicenter database and then categorized according to cisplatin CD (mg/m2) received. All complications and cisplatin-related toxicities during CRT were recorded.ResultsWe identified 779 LA-NPC patients receiving low (£150; n=97), intermediate (151–250; n=411), and high (>250; n=271) CDs of cisplatin. Low CD patients had significantly lower mean actual radiation dose (p<0.001) and more radiotherapy delay (p=0.010), while intermediate CD patients had the least hospitalization (p<0.001). Overall, 39.3% of the patients experienced cisplatin-related toxicity, which was associated with poor overall survival (OS) (p=0.001). Acute kidney injury was observed in 7% in all patients, which was highest among low CD patients (15.5%; p=0.002). Intermediate CD patients had significantly longer median OS than the low and high groups (64 vs. 49.8 vs. 53.2, respectively; p=0.015). Univariate, but not multivariate, analysis showed that CD of cisplatin was significantly associated with OS.ConclusionCD of cisplatin during CRT was not an independent prognostic factor for OS. An intermediate CD induced minimal toxicity without compromising survival and should be considered the optimal CD. Nonetheless, a randomized phase 3 study evaluating the optimal CD of cisplatin is warranted.

VHF antenna pattern characterization by the observation of meteor head echoes

The Middle Atmosphere Alomar Radar System (MAARSY) with its active phased array antenna is designed and used for studies of phenomena in the mesosphere and lower atmosphere. The flexible beam forming and steering combined with a large aperture array allows for observations with a high temporal and angular resolution. For both the analysis of the radar data and the configuration of experiments, the actual radiation pattern needs to be known. For that purpose, various simulations as well as passive and active experiments have been conducted. Here, results of meteor head echo observations are presented, which allow us to derive detailed information of the actual radiation pattern for different beam-pointing positions and the current health status of the entire radar. For MAARSY, the described method offers robust beam pointing and width estimations for a minimum of a few days of observations.

VHF antenna pattern characterization by the observation of meteor head echoes

The Middle Atmosphere Alomar Radar SYstem (MAARSY) with its active phased array antenna is designed and used for studies of phenomena in the mesosphere and lower atmosphere. The flexible beam forming and steering combined with a large aperture array allows observations with high temporal and angular resolution. For both, the analysis of the radar data and the configuration of experiments, the actual radiation pattern needs to be known. For that purpose various simulations as well as passive and active experiments have been conducted. Here, results of meteor head echo observations are presented, which allow derivation of detailed information of the actual radiation pattern for different beam pointing positions and the current health status of the entire radar. For MAARSY, the described method offers robust beam pointing and width estimations for a minimum of a few days of observations.

Pengukuran Laju Paparan Radiasi pada Perisai Radiasi Ruang Panoramik di Instalasi Radiologi Rumah Sakit Islam Klaten

Background: Research about the measurement of radiation exposure rate on panoramic radiation shield in Radiology Installation of Klaten Islamic Hospital has been conducted. The background of this research is in the panoramic room there is a veil that has a gap on the bottom as high as 20 cm. The purpose of this research is to know the rate of radiation exposure on radiation panoramic shield in Radiology Installation of Klaten Islamic Hospital and the application of radiation protection system to the room.Methods: This research type is quantitative with survey approach that is writer do observation, documentation and measurement of exposure rate of radiation at controlled and uncontrolled area by doing measurement at two state that is before exposure (background radiation) and after exposure. The data obtained are then analyzed descriptively to declare a safe examination room or not for workers and the general public by comparing the measurement results with UNSCEAR and NCRP report No. 147.Result: The value of the background exposure rate in the panoramic chamber of the Klaten Hospital Radiology Installation exceeds the value of the background dose rate based on the location of the height of an area according to UNSCEAR. The background exposure value in the panoramic space ranges from 0.14 to 0.175 μGy/hour. The actual radiation exposure measurements at point A is 0.00021 mGy/hour, point B is 0.000175 mGy/h, point C is 0 mGy/hour, point D is 0 mGy/hour, point E is 0.000105 mGy/hour, point G is 0,000735 mGy/hour. These six results have not exceeded the NCRP report no. 147 is for controlled areas 0.0025 mGy / hr and uncontrolled area 0.0005 mGy / hr.