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Organic-inorganic hybrid perovskites (OIHPs) have recently emerged as groundbreaking semiconductor materials owing to their remarkable properties. Transmission electron microscopy (TEM), as a very powerful characterisation tool, has been widely used in perovskite materials for structural analysis and phase identification. However, the perovskites are highly sensitive to electron beams and easily decompose into PbX2 (X = I, Br, Cl) and metallic Pb. The electron dose of general high-resolution TEM is much higher than the critical dose of MAPbI3 , which results in universal misidentifications that PbI2 and Pb are incorrectly labelled as perovskite. The widely existed mistakes have negatively affected the development of perovskite research fields. Here misidentifications of the best-known MAPbI3 perovskite are summarised and corrected, then the causes of mistakes are classified and ascertained. Above all, a solid method for phase identification and practical strategies to reduce the radiation damage for perovskite materials have also been proposed. This review aims to provide the causes of mistakes and avoid misinterpretations in perovskite research fields in the future.

The addition of compounds to scavenge the radical species produced during biological small-angle X-ray scattering (BioSAXS) experiments is a common strategy to reduce the effects of radiation damage and produce better quality data. As almost half of the experiments leading to structures deposited in the SASBDB database used scavengers, finding potent scavengers would be advantageous for many experiments. Here, four compounds, three nucleosides and one nitrogenous base, are presented which can act as very effective radical-scavenging additives and increase the critical dose by up to 20 times without altering the stability or reducing the contrast of the tested protein solutions. The efficacy of these scavengers is higher than those commonly used in the field to date, as verified for lysozyme solutions at various concentrations from 7.0 to 0.5 mg ml−1. The compounds are also very efficient at mitigating radiation damage to four proteins with molecular weights ranging from 7 to 240 kDa and pH values from 3 to 8, with the extreme case being catalase at 6.7 mg ml−1, with a scavenging factor exceeding 100. These scavengers can therefore be instrumental in expanding BioSAXS to low-molecular-weight and low-concentration protein samples that were previously inaccessible owing to poor data quality. It is also demonstrated that an increase in the critical dose in standard BioSAXS experiments leads to an increment in the retrieved information, in particular at higher angles, and thus to higher resolution of the model.

Centro de Investigación Forestal (CIFOR), The objective of this study is to evaluate the effect of the species on the biological resistance of wood against decay and to propose corrective values of the critical dose. To evaluate the species effect, the evolution of the number of days per year with moisture content exceeding 18% was assessed in flat sawn 20x100x750 mm3 test samples of Laricio, Scots and Radiata pines and also of Norway spruce, Eucalypt (globulus) and sweet chestnut during the years 2016, 2017 and 2018, exposed at seven locations in Spain with the most representative Spanish climates. A value of 1.0 is proposed for the four conifers, 2.51 for the Eucalypt and 1.84 for the Sweet chestnut. As regards the species effect it was not possible to separate that corresponding to the different wetting/releasing ability of each species and that of their crack susceptibility, both aspects having to be evaluated together as “species factor”., This work was carried out in the Wood Technology Laboratories at the CIFOR-INIA and University of Córdoba, and was financially supported under the Spanish National RDT Planthrough Grant BIA2013-42434-R and the Operational Group “Wood Sustainable Construction” of the European Association fo rInnovation in Agricultural Productivity and Sustainability (AEI-AGRI)., 13 Pág.

Water distribution networks are critical infrastructure systems that are vulnerable to terrorist attack. Water utility management has the goal of protecting public health by allocating countermeasures, including security equipment and personnel, as a first line of defense. A malevolent actor may select an attack location, however, using a set of unknown priorities that include performance and susceptibility criteria. This research develops a multi-agent framework to simulate the attack and defense of a distribution system to analyze security resource allocation strategies for protecting against chemical contamination events. A single period attacker-defender game is simulated, in which an attacker seeks to contaminate a system node with high attack utility, and a group of defenders seeks to minimize the public health impact from intentional attack. Terrorist agent decisions are simulated using a multi-attribute utility function, and multiple cases are constructed to simulate alternative rankings of criteria. The water utility manager agent assigns security personnel and deterrent security equipment to nodes using one of three security resource allocation strategies. The agent-based modeling framework is applied to simulate attack and defense for a virtual municipality, D -town. Strategies are evaluated based on the number of consumers exposed to a critical dose when a contaminant is released.

Ying Wang,1 Sheng-Gang Sun,2 Sui-Qiang Zhu,3 Chun-Feng Liu,4 Yi-Ming Liu,5 Qing Di,6 Hui-Fang Shang,7 Yan Ren,8 Wei Xiang,9 Sheng-Di Chen1 1Department of Neurology, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, 2Department of Neurology, Union Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology, Wuhan, 3Department of Neurology, Tongji Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology, Wuhan, 4Department of Neurology, The Second Affiliated Hospital of Soochow University, Suzhou, 5Department of Neurology, Qilu Hospital Affiliated to Shandong University, Jinan, 6Department of Neurology, Nanjing Brain Hospital, Nanjing, 7Department of Neurology, West China Hospital Affiliated to Sichuan University, Chengdu, 8Department of Neurology, First Affiliated Hospital of China Medical University, Shenyang, 9Medical Department, Boehringer Ingelheim (China) Investment Co., Ltd., Shanghai, People’s Republic ofChina Background: Pramipexole (PPX), a non-ergot dopamine receptor agonist, is a first-line treatment for Parkinson’s disease (PD). A critical dose level above which a better benefit-to-harm ratio exists has not been examined.Methods: Chinese PD patients (n=464) were retrospectively analyzed by PPX maintenance dose, PD stage, combined levodopa dose, and baseline tremor contribution. The sum score of Baseline Activities of Daily Living (part II) and Motor Examination (III) of the Unified Parkinson’s Disease Rating Scale (UPDRS II+III) was used as a covariate for final score adjustment.Results: Sustained-release (SR) and immediate-release (IR) PPX showed similar efficacy based on score changes at 18 weeks, with comparable tolerability. Approximately two-third of patients received PPX at ≥1.5 mg/d, and one fourth of patients had ≥20% tremor contribution to UPDRS II+III. After treatment, patients receiving PPX ≥1.5 mg/d showed better improvement in UPDRS II+III scores (P=0.0025), with similar trends with the IR and SR formulations. Patients with ≥20% tremor contribution showed better improvement in UPDRS II+III scores (P=0.0017). No differences were seen based on PD stage or combined levodopa dose. The overall proportions of adverse events (AEs) were similar. More patients discontinued because of intolerable side effects, and more investigator-defined drug-related AEs were recorded in the

The recent development of atomic resolution, low dose-rate electron microscopy allows investigating 2D materials as well as catalytic nano particles without compromising their structural integrity. For graphene and a variety of nanoparticle compositions, it is shown that a critical dose rate exists of100 e(-)/Å(2) s at 80 keV of electron acceleration that allows maintaining the genuine object structures including their surfaces and edges even if particles are only 3 nm large or smaller. Moreover, it is demonstrated that electron beam-induced phonon excitation from outside the field of view contributes to a contrast degradation in recorded images. These degradation effects can be eliminated by delivering electrons onto the imaged area, only, by using a Nilsonian illumination scheme in combination with a suitable aperture at the electron gun/monochromator assembly.

To increase the efficacy of radiotherapy for non-small cell lung cancer (NSCLC), many schemes of dose fractionation were assessed by a new "toxicity index" (I), which allows one to choose the fractionation schedules that produce less toxic treatments. Thirty-two patients affected by non resectable NSCLC were treated by standard 3-dimensional conformal radiotherapy (3DCRT) with a strategy of limited treated volume. Computed tomography datasets were employed to re plan by simultaneous integrated boost intensity-modulated radiotherapy (IMRT). The dose distributions from plans were used to test various schemes of dose fractionation, in 3DCRT as well as in IMRT, by transforming the dose-volume histogram (DVH) into a biological equivalent DVH (BDVH) and by varying the overall treatment time. The BDVHs were obtained through the toxicity index, which was defined for each of the organs at risk (OAR) by a linear quadratic model keeping an equivalent radiobiological effect on the target volume. The less toxic fractionation consisted in a severe/moderate hyper fractionation for the volume including the primary tumor and lymph nodes, followed by a hypofractionation for the reduced volume of the primary tumor. The 3DCRT and IMRT resulted, respectively, in 4.7% and 4.3% of dose sparing for the spinal cord, without significant changes for the combined-lungs toxicity (p < 0.001). Schedules with reduced overall treatment time (accelerated fractionations) led to a 12.5% dose sparing for the spinal cord (7.5% in IMRT), 8.3% dose sparing for V-20 in the combined lungs (5.5% in IMRT), and also significant dose sparing for all the other OARs (p < 0.001). The toxicity index allows to choose fractionation schedules with reduced toxicity for all the OARs and equivalent radiobiological effect for the tumor in 3DCRT, as well as in IMRT, treatments of NSCLC. (C) 2014 American Association of Medical Dosimetrists.

Wood is one of the most important construction materials, and its use in building applications has increased in recent decades. In order to enable even more extensive and reliable use of wood, we need to understand the factors affecting wood&rsquo, s service life. A new concept for characterizing the durability of wood-based materials and for predicting the service life of wood has recently been proposed, based on material-inherent protective properties, moisture performance, and the climate- and design-induced exposure dose of wooden structures. This approach was validated on the decking of a model house in Ljubljana that was constructed in October 2013. The decay and moisture content of decking elements were regularly monitored. In addition, the resistance dose DRd, as the product of the critical dose Dcrit, and two factors taking into account the wetting ability of wood (kwa) and its inherent durability (kinh), were determined in the laboratory. DRd correlated well with the decay rates of the decking of the model house. Furthermore, the positive effect of thermal modification and water-repellent treatments on the outdoor performance of the examined materials was evident, as well as the synergistic effects between moisture performance and inherent durability.

The feasibility of using Deinococcus showing strong resistance to both desiccation and ionizing radiation as a dose indicator of gamma radiation exposure was evaluated. Three Deinococcus strains having different levels of radiation resistance, Deinococcus radiodurans (DRD), Deinococcus radiopugnans (DRP), and the DRD pprI mutant (DRM), were selected to develop an appropriate dose indicator for a broad range of exposures. DRD, DRP, and DRM cultures with different numbers of cells [~10(7) to 10(3) colony forming units (CFU)/100 microliter] were lyophilized and subjected to various doses of gamma radiation to determine a critical dose that inhibited bacterial growth completely. Finally, a combination of DRD at ~10(7) and ~10(6) CFU, DRP at ~10(5) CFU, and DRM at ~10(4) CFU successfully indicated exposure to 5, 10, 20, and 30 kGy of gamma radiation, respectively. This study shows the possibility of developing a qualitative indicator of radiation exposure using Deinococcus.

Ion-implantation characteristics and dopant activation behavior of P in Ge have been investigated. A Monte Carlo simulation indicates a smaller projected range and consequently a smaller critical dose of amorphization for Ge compared to Si. The solid-phase epitaxial (SPE) regrowth characteristics of damaged layers for Ge clearly depend on crystal orientation of the substrate in completely amorphized samples, while no orientation dependent regrowth is observed in the partially amorphized samples. These phenomena were explained on the basis of the damage cluster model. In addition, maximum carrier activation coincides with the complete regrowth at annealing temperatures of 300–400 °C in completely amorphized samples. However, higher temperature annealing (500–550 °C) is necessary for maximum carrier activation in partially amorphized samples, although SPE regrowth completes around 250–300 °C. Analysis of the temperature dependence of carrier activation ratio in partially amorphized samples suggests that carrier-activation should be mediated by vacancy-migration.

It is demonstrated that the method of data analysis, i.e., the method of the phenomenological/theoretical interpretation of dose response data, can greatly influence the estimation of the onset of deviation from dose response linearity of the high temperature thermoluminescence in LiF:Mg,Ti (TLD-100).

Radiation resistance of cross-linked polytetrafluoroethylene (XPTFE) sheets was evaluated by measuring the friction and wear properties as well as observing the morphology after gamma-irradiation in air at room temperature. The wear resistance of XPTFE was confirmed to be much higher than that of virgin PTFE. The friction coefficient of XPTFE decreased with increasing dose, whereas the wear resistance remained stable until a critical dose was reached and then decreased sharply with dose. The critical dose of wear resistance was dependent on the crosslinking density or crosslinking dose of XPTFE. The radiation resistance of XPTFE improved significantly due to the formation of three-dimensional crosslinking networks by irradiation in the molten state. In addition, morphologies of the abraded debris of virgin PTFE and XPTFE were also compared and a clear difference was observed. (C) 2010 Elsevier Ltd. All rights reserved.

BACKGROUND CONTEXT While the incidence of spinal metastases is constantly increasing, the combination of kyphoplasty and intraoperative radiation (Kypho-IORT) is a good possibility not only to gain additional histopathologic data but also to achieve excellent pain and local tumor control. The clinical effectiveness in terms of local tumor control is comparable to SBRT, the pain control far better. The pros of Kypho-IORT are the minimal invasiveness and the one-stop-shop-procedure with effective and instantaneous pain control. PURPOSE The aim of this study is the retrospective density-corrected dose planning in the tumor and the proof of safety for the risk-organ spinal canal on basis of consecutive clinical performed Kypho-IORTs. STUDY DESIGN/SETTING Experimental study, single cohort. PATIENT SAMPLE A total of 10 consecutive cases appointed for Kypho-IORT. OUTCOME MEASURES Sufficient dosing of the metastasis sparing of organs at risk. METHODS We performed Monte-Carlo-based 3D-dose planning in the tumor and in the spinal canal, by using the new planning-software Radiance (GMV Healthcare, Madrid, Spain) in 10 consecutive Kypho-IORTs (Dose 8 Gy in 13 mm distance from the isocenter, 50 kV-xray-source, Intrabeam XRS4, Zeiss meditech AG). Pre- and intraoperative imaging (cone-beam-CT: Siemens Zeego) was used for the dose calculation. Due to metal-artifacts in the intraoperative-cone-beam-CT a preoperative multislice-CT had to be used for calculating the dose, therefore a matching of both CTs had to be performed. RESULTS The distance of the geometrical centre of the metastasis and the coordinates of the applicator tip (isocenter of radiation) could be calculated by vector analysis, the dose distribution was calculated density-corrected. In 7 out of 10 cases, the distance was larger than 5 mm, not correlating to the size of the metastasis itself. In 8 of 10 cases, 70% of the metastasis volume was treated with the prescribed dose of 8 Gy, in 2 cases this treatment-goal was missed. In all 10 cases no dose over 8 Gy reached the spinal canal, the myelon was never exposed to a potential harmful dose. CONCLUSIONS We could show that the Kypho-IORT is not only an effective and safe method, but also an exact quantifiable method, especially in contrast to other methods like thermoablation. The organs at risk are not exposed to a critical dose, the metastasis volume was acceptable covered (8/10 cases >70% of the volume treated with >8 Gy).The next step to further enhance the potential of the procedure in terms of a patient individual dosage will be the intraoperative dose-planning and modification of the delivered dose. A different approach via inverse-planning could be the navigation of the applicator.But also without individual dose-planning Kypho-IORT reached excellent clinical results in terms of local tumor control by using the standard dose of the dose-escalation trial (8 Gy in 13 mm distance of the Isocenter).

The dicentric chromosome assay (DCA) is the gold-standard assay for accurately estimating unknown radiological doses to individuals following radiological or nuclear accidents. However in a mass-casualty scenario, this assay is not well suited for providing timely dose estimates due to its time- and expertise-intensive nature. In Canada, two approaches are being developed in an attempt to increase triage-quality biological dosimetry throughput. These are 1) increasing the number of trained personnel capable of conducting the DCA, and 2) evaluating alternative biodosimetry approaches or DCA variations. In a recent exercise, a new scoring technique (termed DCA QuickScan) was evaluated as an alternative rapid-scoring approach. Triage-quality conventional DCA and DCA QuickScan analysis were based upon scoring a minimum of 50 metaphase cells or 30 dicentrics by 9-15 scorers across four laboratories. Dose estimates for the conventional DCA were found to be within 0.5 Gy of the actual dose for 83% of the unknown samples, while DCA QuickScan dose estimates were within 0.5 Gy for 80% of the samples. Of the dose estimates falling 0.5 Gy or more outside the actual dose, the majority were dose over-estimates. It was concluded that the DCA QuickScan approach can provide critical dose information at a much faster rate than the conventional DCA without sacrificing accuracy. Future studies will further evaluate the accuracy of the DCA QuickScan method.

Critical dose of X-ray amorphization of the garnet phase Ca1.5Gd0.908Cm0.092Th0.5ZrFe4O12, which is the base of the synthetic ceramics doped with 241Cm (∼2 wt %), was determined. Amorphization occurs at a dose of 1.6 × 1018 α-decay g−1 or 0.17 dpa (displacements per atom). The chemical resistance of the amorphized ceramics to leaching (MCC-1 test) is comparable to that of the initial ceramics. The rates of Cm leaching from the freshly prepared and amorphized ceramics decrease with time and after storage for two weeks amount to 1.4 × 10−3 and 5.8 × 10−3 g m−2 day−1, respectively. Data on thermal restoration of the crystal structure of the ceramics are also presented.

In the framework of a comparison between three laboratories, electron paramagnetic resonance (EPR) signal-to-dose response curves were measured for sets of 30 tooth enamel samples and the variance of EPR measurements in dependence on absorbed dose was evaluated, in nine combinations of laboratory of sample preparation and EPR evaluation, respectively. As a test for benchmarking of EPR evaluation, the parameters ‘critical dose’ and ‘limit of detection’ were proposed as performance parameters following definitions from chemical-metrology, and a model function was suggested for analytical formulation of the dependence of the variance of EPR measurement on absorbed dose. First estimates of limits of detection by weighted and unweighted fitting resulted in the range 101–552 and 67–561 mGy, respectively, and were generally larger with weighted than with unweighted fitting. Indication was found for the influence of methodology of sample preparation and applied EPR measurement parameters on performance of EPR dosimetry with tooth enamel.

A new model of radiation disordering of semiconductors is proposed. According to this model, disordering clusters capable of self-annealing are stabilized by auto-localized electronic excitations (...

The data processing method of the turbidimetric bioassay of nisin was modified to facilitate its industrial application. The influence of the initial indicator concentration was minimized by a redefined specific dose of the bacteriocin as the quotient between the titer of the added bacteriocin and the initial population density of the indicator in the suspension. It was found that dc = 0.125 microg ml(-1) was the critical dose of nisin that can cause a complete inhibition of the indicator, Pediococcus acidilactici UL5, with an initial OD of 0.135. To eliminate the interference of the cell debris, an equation, epsilonI = ODi(1-di)/OD0 = epsilonA(1-di/dc), exploiting dc, was formulated to obtain the intrinsic survival proportion. The use of the specific dose of the bacteriocin and the intrinsic survival proportion as parameters of the dose/response curve greatly enhanced its repeatability and feasibility. A dual-dosage approach was developed to further simplify the conventional standard dose/response curve method.

Extracorporeal shock waves (ESW) have been extensively studied in the field of orthopedics. Experimental and focused, well-designed clinical studies have suggested the clinical utilisation of ESW in several pathologies including delayed bone union, tennis elbow, and plantar fasciitis. However, the unwanted detrimental effects of ESW on various tissues have been questioned by some authors. In this experimental study, the effects of ESW were investigated at different intensity applications on the Achilles tendons of rat. A total of 32 adult Wistar albino rats was divided into four groups. The first three groups received 1000 impulses of 0.15 mJ/mm2, 1500 impulses of 0.15 mJ/mm2, and 2000 impulses of 0.20 mJ/mm2, respectively. The last group was kept as the control group. Subsequently, Achilles tendons were harvested for histological studies from all rats at the 3rd week after a single application of ESW. There were no histological abnormalities observed in the Achilles tendons of the first two groups compared with the control group. No alteration in the histological configuration was observed, and consequently the pathologist who had been blinded could not differentiate these rats from the control group by light microscopy. However, in the high intensity group (2000 impulses of 0.20 mJ/mm2), grade II and III disorganisation of collagen fibers was noticed in 7 out of 8 rats, which was not detected in any of the rats from the first two groups (p

To estimate the critical dose of the association between the blood lead concentration (BPb) and delta-aminolevulinic acid (ALA) levels, ALA levels in plasma (ALA-P), blood (ALA-B), and urine (ALA-U), and the activity of delta-aminolevulinic acid dehydratase (ALAD) were determined in 186 Japanese lead workers, aged 18-62 yr, with BPb levels of 2.1-62.9 g/dl. For this purpose, the benchmark dose (BMD) method, recently used in the environmental health field in place of the no-observed-adverse-effect level, was introduced into this study. The BMD was defined as the BPb level that resulted in an increased probability of abnormal change in ALA-related parameters by an excess risk (BMR) of 5% in exposed workers i.e., from P0 (abnormal probability of 5% in unexposed workers) to P0+BMR for exposed workers at the BMD. ALA-related parameters were significantly correlated with BPb. The BMDs computed from the 186 workers, after controlling for age, were 15.3-20.9 microg/dl for ALA levels, and 2.9 microg/dl for ALAD; likewise, the BMDs from the 154 workers with BPb levels of less than 40 microg/dl were 3.3-8.8 microg/dl for ALA levels, and 2.7 microg/dl for ALAD. Since the cutoff value of ALA-P, computed from the latter workers, seems to be closer to the upper normal limit in unexposed adults than does that from the former workers, it is suggested that the critical dose of BPb causing the increased levels of ALA is below 10 microg/dl. Such critical doses are necessary to promote preventive activities of adverse effects of lead.

Germination efficiency and root/shoot length of germinated seedling is proposed to identify irradiated lentil seeds. Germination percentage was reduced above 0.2 kGy and lentil seeds were unable to germinate above 1.0 kGy dose. The critical dose that prevented the root elongation varied from 0.1 to 0.5 kGy. The sensitivity of lentil seeds to gamma irradiation was inversely proportional to moisture content of the seeds. Radiation effects could be detected in seeds even 12 months storage after gamma irradiation.

In this paper radiation performance of 4T, 6T, 7T, 8T and 10T MOSFET based-SRAMs are studied using TCAD simulations. The minimum dose (critical dose) required to flip contents of the cell are extracted, compared and analyzed. The simulation results show that 10T SRAM shows better radiation performance whereas 4T-SRAM shows worst radiation performance.

The temperature dependence of the amorphization in α-quartz by Ne-ion bombardment has been investigated using Rutherford Backscattering Spectrometry in channeling geometry (RBS-C). The experimental results show that the critical temperature Tc for inhibiting amorphization in quartz is around 940 K. The damage depth profile χ(z,φ) is independent of the temperature and fluence and can be simulated with a power-law function [χ(z,φ)∝(φFD(z))3] of the damage energy distribution FD(z). At low irradiation temperature, the critical dose φc for amorphization is independent of the temperature but it strongly increases at higher temperatures with an activation energy of 0.28 eV and has been explained by out-diffusion model of Morehead and Crowder.

Planktonic larvae and just settled juveniles of the sea urchin, Strongylocentrotus intermedius, were irradiated with various quantities of UV rays, and the effects 24 hrs after keeping them under a condition 10 L:14 D at 16°C (larvae) or 17°C (juveniles) were observed. The results showed that blastula and pluteus larvae were seriously damaged by irradiation of UV-B (280-320nm) and UV-A (320-400nm). A critical dose of damaging UV (DUV) which induced more than 30% morphologi-cally abnormal larvae was 0.01kJ/m2 for blastula and 4-armed larvae. It gradually increased to 0.05 and 0.08kJ/m2 as the stage advanced to the 6-armed and 8-armed stages, respectively. No effects were observed for juveniles after 24hrs of irradiation of 0.7kJ/m2 DUV, but all the juveniles which received more than 0.2kJ/m2 died within 1 month. It was suggested that the reproduction of the sea urchin might be affected by sun light in shallow water, since a maximum of the mean daily amount of DUV was reported to be 0.7kJ/m2 in July, 1994, in Sapporo.