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With the ongoing expansion of global observation networks, it is expected that we shall routinely analyze records of geophysical variables such as temperature from multiple collocated instruments. Validating datasets in this situation is not a trivial task because every observing system has its own bias and noise. Triple collocation is a general statistical framework to estimate the error characteristics in three or more observational-based datasets. In a triple colocation analysis, several metrics are routinely reported but traditional multiple-panel plots are not the most effective way to display information. A new formula of error variance is derived for connecting the key terms in the triple collocation theory. A diagram based on this formula is devised to facilitate triple collocation analysis of any data from observations, as illustrated using three aerosol optical depth datasets from the recent Aerosol Cloud meTeorology Interactions oVer the western ATlantic Experiment (ACTIVATE). An observational-based skill score is also derived to evaluate the quality of three datasets by taking into account both error variance and correlation coefficient. Several applications are discussed and sample plotting routines are provided. [ABSTRACT FROM AUTHOR]

The purpose of this article is to further investigate the assisted cloning of a d-dimensional arbitrary unknown state by utilizing quantum teleportation (QT) and remote state preparation (RST) techniques. We first propose a scheme for cloning an arbitrary unknown single-qudit state with assistance from a state preparer. In this scheme, the maximally and non-maximally bipartite d-dimensional states are used as quantum channels, respectively. In the first stage of scheme requires usual QT and in the second stage, the state preparer disentangles the left over entangled states by introducing one auxiliary qudit and performing a generalized CNOT, a single-qudit positive operator-valued measurement (POVM) and a single-qudit projective measurement process and conveys some classical messages to different parties so that a copy is produced probabilistically with the unit fidelity. Then by replacing the maximally or non-maximally bipartite d-dimensional entangled channel with a sequence of maximally or non-maximally bipartite d-dimensional entangled states as a quantum channel, we can extend the above scheme to the case of cloning a d-dimensional arbitrary unknown m-qudit state with the unit fidelity and a certain probability in the help of the state preparer. [ABSTRACT FROM AUTHOR]

Background: Improving the accuracy of relative stopping power (RSP) in proton therapy may allow reducing range margins. Proton computed tomography (pCT) has been shown to provide state‐of‐the‐art RSP accuracy estimation, and various scanner prototypes have recently been built. The different approaches used in scanner design are expected to impact spatial resolution and RSP accuracy. Purpose: The goal of this study was to perform the first direct comparison, in terms of spatial resolution and RSP accuracy, of two pCT prototype scanners installed at the same facility and by using the same image reconstruction algorithm. Methods: A phantom containing cylindrical inserts of known RSP was scanned at the phase‐II pCT prototype of the U.S. pCT collaboration and at the commercially oriented ProtonVDA scanner. Following distance‐driven binning filtered backprojection reconstruction, the radial edge spread function of high‐density inserts was used to estimate the spatial resolution. RSP accuracy was evaluated by the mean absolute percent error (MAPE) over the inserts. No direct imaging dose estimation was possible, which prevented a comparison of the two scanners in terms of RSP noise. Results: In terms of RSP accuracy, both scanners achieved the same MAPE of 0.72% when excluding the porous sinus insert from the evaluation. The ProtonVDA scanner reached a better overall MAPE when all inserts and the body of the phantom were accounted for (0.81%), compared to the phase‐II scanner (1.14%). The spatial resolution with the phase‐II scanner was found to be 0.61 lp/mm, while for the ProtonVDA scanner somewhat lower at 0.46 lp/mm. Conclusions: The comparison between two prototype pCT scanners operated in the same clinical facility showed that they both fulfill the requirement of an RSP accuracy of about 1%. Their spatial resolution performance reflects the different design choices of either a scanner with full tracking capabilities (phase‐II) or of a more compact tracker system, which only provides the positions of protons but not their directions (ProtonVDA). [ABSTRACT FROM AUTHOR]

Introduction: Respirable Suspended Particulate (RSP) is a particularly serious indoor air pollution since at least a portion of particles ingested by humans can be permanently deposited in the respiratory tract. Analysis of indoor air quality in school classrooms is essential because the air quality can have a significant impact on the health and performance of children. Methods: The site selections were based on the surrounding activities of commercial and industrial areas. Instruments used for measuring parameters are Dust TraxTM DRX Aerosol II 8532 and Kanomax IAQ Monitor. Results: The study shows that the commercial area has a higher concentration of RSP compared to the industrial area. The I/O ratio value is higher at commercial area compared to industrial area with the value of PM10 = 3.065, PM2.5 = 3.222, PM1 = 3.261, CO2 =1.242, RH = 1.212, temperature = 0.891, and air movement = 1.072 for commercial area, and PM10 = 1.482, PM2.5 = 1.456, PM1 = 1.449, CO2 =1.116, RH = 1.134, temperature = 1.040, and air movement = 1.008 for the industrial area. For a commercial area, the indoor RSP is strongly correlated to all meteorological parameters with the value exceeding 0.5 except for CO2 has moderately correlated with the value is between 0.4 to 0.49, and wind speed has weak correlate with the value is less than 0.39. Conclusion: In conclusion, the classroom located in commercial is more polluted compared to the industrial area and the RSP is significantly influenced by meteorological factors. [ABSTRACT FROM AUTHOR]

In this study, we propose a simple method to derive vertically resolved aerosol particle number concentration (Na) using combined polarimetric and lidar remote sensing observations. This method relies on accurate polarimeter retrievals of the fine-mode column-averaged aerosol particle extinction cross section and accurate lidar measurements of vertically resolved aerosol particle extinction coefficient such as those provided by multiwavelength high spectral resolution lidar. We compare the resulting lidar + polarimeter vertically resolved Na product to in situNa data collected by airborne instruments during the NASA aerosol cloud meteorology interactions over the western Atlantic experiment (ACTIVATE). Based on all 35 joint ACTIVATE flights in 2020, we find a total of 32 collocated in situ and remote sensing profiles that occur on 11 separate days, which contain a total of 322 cloud-free vertically resolved altitude bins of 150 m resolution. We demonstrate that the lidar + polarimeter Na agrees to within 106% for 90% of the 322 vertically resolved points. We also demonstrate similar agreement to within 121% for the polarimeter-derived column-averaged Na. We find that the range-normalized mean absolute deviation (NMAD) for the polarimeter-derived column-averaged Na is 21%, and the NMAD for the lidar + polarimeter-derived vertically resolved Na is 16%. Taken together, these findings suggest that the error in the polarimeter-only column-averaged Na and the lidar + polarimeter vertically resolved Na are of similar magnitude and represent a significant improvement upon current remote sensing estimates of Na.

Copyright of Nouvelles Pratiques Sociales is the property of Revue Nouvelles Pratiques Sociales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Background There is low diagnostic accuracy of the proxy restrictive spirometric pattern (RSP) to identify true pulmonary restriction. This knowledge is based on patients referred for spirometry and total lung volume determination by plethysmograpy, single breath nitrogen washout technique or gas dilution and selected controls. There is, however, a lack of data from general populations analyzing whether RSP is a valid proxy for true pulmonary restriction. We have validated RSP in relation to true pulmonary restriction in a general population where we have access to measurements of total lung capacity (TLC) and spirometry. Methods The data was from the Swedish CArdioPulmonary bioImage Study (SCAPIS Pilot), a general population-based study, comprising 983 adults aged 50–64. All subjects answered a respiratory questionnaire. Forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) were obtained before and after bronchodilation. TLC and residual volume (RV) was recorded using a body plethysmograph. All lung function values are generally expressed as percent predicted (% predicted) or in relation to lower limits of normal (LLN). True pulmonary restriction was defined as TLC

ABSTRACTStaphylococcus aureus is a major human pathogen that causes a great diversity of community- and hospital-acquired infections. Rsp, a member of AraC/XylS family of transcriptional regulators (AFTRs), has been reported to play an important role in the regulation of virulence determinants in S. aureus via an agr-dependent pathway. Here we demonstrated that Rsp could bind to the rsp promoter to positively regulate its own expression. We then constructed an isogenic rsp deletion strain and compared the haemolysis in the wild-type and rsp mutant strains. Our results indicated that the rsp mutant strain displayed decreased haemolytic activity, which was correlated with a dramatic decrease in the expression of hla and psm. Furthermore, we analysed the regulatory effects of Rsp in the agr mutant strain and found that they are agr-independent. Electrophoretic mobility shift assay indicated that Rsp can directly bind to the promoter regions of hla and psm. The mouse model of subcutaneous abscess showed that the rsp mutant strain displayed a significant defect in virulence compared to the wild-type strain. These findings reveal that Rsp positively regulates the virulence of S. aureus by promoting the expression of hla and psm through direct binding to their promoter regions.

The heavy metals contamination in soil has attracted increasing attention. In this study, the main objective was to determine three heavy metals (Cd, Pb, and Cr) of soils contaminated by smelting waste, and to evaluate pollution risk. The Pb (15.48 mg/kg) and Cd (311.39 mg/kg) mean concentrations exceeded the national standard, while Cr (48.60 mg/kg) concentration did not exceed. The Heavy metal fractions analysis showed that three heavy metals were dominated by FeMn oxides fraction (Fe-Mn). The correlation and cluster analysis indicated that there was significant correlation between Cd and Pb (0.55< r < 0.96), while Cr was not correlation to Cd and Pb. The environmental pollution of heavy metals was assessed by the ratio of secondary phase and primary phase (RSP). The result showed that RSP values of Cd, Pb, and Cr range from 13.05–54.28, 16.11–4.97 and 1.61–52.33, which indicated soil was serious contaminated by them. These results showed that smelting waste discharge led to this smelter soil being seriously contaminated by multiple heavy metals which have a tendency to transport and accumulate into deep soil due to their high fractional transformation.

This study provides a review of the literature published on Public Service Broadcasting (PSB) between the years 2009 and 2019. In total, 232 articles were obtained following a literature search of five databases (Scopus, Web of Science Core Collection, ProQuest, Academic Search Ultimate, and Google Scholar), of which seventy-eight were deemed relevant, based on the study criteria. The article summarizes the objects of study, settings under analysis, methodological approaches, and principal thematic patterns of extant research, providing a critical assessment of the main findings and research directions. Based on this thematic summary, the study offers suggestions on how to move forward and identify some of the main challenges and limitations on this area of inquiry. [ABSTRACT FROM AUTHOR]

This paper is about to compare the electrical performance of conventional FD-SOI MOSFET with the BOX integrated substrate SOI MOSFET. The performance is compared and contrasted with the help of electric field, energy band diagram, surface potential, gate material (variation of workfunction) and parasitic capacitances. On comparison the proposed structure shows high Ion/Ioff ratio, high RSP, lower sub-threshold slope and lower threshold voltage then the conventional FD-SOI MOSFET. The performance of the proposed structure is also studied by the variation of buried oxide (BOX) thickness and the overlapped SOI (LSOI) region. Interestingly, by decreasing the thickness of BOX and LSOI region, the leakage current is decreasing without affecting the on-state current and the threshold voltage, thus increasing the Ion/Ioff ratio and decreasing the sub-threshold slope. In addition, this work also shows the improved analog performance in terms of transconductance (gm), gate to drain capacitance (Cgd), gate to source capacitances (Cgs), and cut-off frequency as compared to conventional FD-SOI MOSFET. The comparative study shows that the proposed structure is compatible for the digital as well as analog application without affecting the current fabrication process flow of the conventional FD-SOI MOSFET. Sentaurus two-dimensional simulations are used to analyze the performance of the proposed structure. [ABSTRACT FROM AUTHOR]

The evolution of the coastal fringe is closely linked to the impact of climate change, specifically increases in sea level and storm intensity. The anthropic pressure that is inflicted on these fragile environments strengthens the risk. Therefore, numerous research projects look into the possibility of monitoring and understanding the coastal environment in order to better identify its dynamics and adaptation to the major changes that are currently taking place in the landscape. This new study aims to improve the habitat mapping/classification at Very High Resolution (VHR) using Pleiades–1–derived topography, its morphometric by–products, and Pleiades–1–derived imageries. A tri–stereo dataset was acquired and processed by image pairing to obtain nine digital surface models (DSM) that were 0.50 m pixel size using the free software RSP (RPC Stereo Processor) and that were calibrated and validated with the 2018–LiDAR dataset that was available for the study area: the Emerald Coast in Brittany (France). Four morphometric predictors that were derived from the best of the nine generated DSMs were calculated via a freely available software (SAGA GIS): slope, aspect, topographic position index (TPI), and TPI–based landform classification (TPILC). A maximum likelihood classification of the area was calculated using nine classes: the salt marsh, dune, rock, urban, field, forest, beach, road, and seawater classes. With an RMSE of 4 m, the DSM#2–3_1 (from images #2 and #3 with one ground control point) outperformed the other DSMs. The classification results that were computed from the DSM#2–3_1 demonstrate the importance of the contribution of the morphometric predictors that were added to the reference Red–Green–Blue (RGB, 76.37% in overall accuracy, OA). The best combination of TPILC that was added to the RGB + DSM provided a gain of 13% in the OA, reaching 89.37%. These findings will help scientists and managers who are tasked with coastal risks at VHR.

Background: There is low diagnostic accuracy of the proxy restrictive spirometric pattern (RSP) to identify true pulmonary restriction. This knowledge is based on patients referred for spirometry and total lung volume determination by plethysmograpy, single breath nitrogen washout technique or gas dilution and selected controls. There is, however, a lack of data from general populations analyzing whether RSP is a valid proxy for true pulmonary restriction. We have validated RSP in relation to true pulmonary restriction in a general population where we have access to measurements of total lung capacity (TLC) and spirometry.Methods: The data was from the Swedish CArdioPulmonary bioImage Study (SCAPIS Pilot), a general population-based study, comprising 983 adults aged 50-64. All subjects answered a respiratory questionnaire. Forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) were obtained before and after bronchodilation. TLC and residual volume (RV) was recorded using a body plethysmograph. All lung function values are generally expressed as percent predicted (% predicted) or in relation to lower limits of normal (LLN). True pulmonary restriction was defined as TLC < LLN5 defined as a Z score < - 1.645, i e the fifth percentile. RSP was defined as FEV1/FVC ≥ LLN and FVC < LLN after bronchodilation. Specificity, sensitivity, positive and negative likelihood ratios were calculated, and 95% confidence intervals (CIs) were calculated.Results: The prevalence of true pulmonary restriction was 5.4%, and the prevalence of RSP was 3.4%. The sensitivity of RSP to identify true pulmonary restriction was 0.34 (0.20-0.46), the corresponding specificity was 0.98 (0.97-0.99), and the positive likelihood ratio was 21.1 (11.3-39.4) and the negative likelihood ratio was 0.67 (0.55-0.81).Conclusions: RSP has low accuracy for identifying true pulmonary restriction. The results support previous observations that RSP is useful for ruling out true pulmonary restriction. [ABSTRACT FROM AUTHOR]

• Hydraulic and mass transfer performances of the RSP200X commercial hybrid packing are reported. • The manufacturer software (Winsorp) has been modified to predict flooding limits of X-Style RSP at high liquid loads. • The hybrid nature of RSP200X leads to significant gas flow rate effects on mass transfer rates. The RSP200X, as one of the latest generation of Raschig's structured packings (Raschig Super-Pak, RSP), has been investigated for use in scrubbing columns operating at high liquid loads where it could be particularly well adapted. These RSP packings offer a good potential for increasing capacity while maintaining mass transfer efficiencies at high levels. IFPEN has measured hydraulic and mass transfer performances in two columns of different diameters (146 mm and 1000 mm). Flooding limits were in agreement with literature, however at high liquid loads and for the tested X-Style RSP they were 30–40% lower than those calculated with the Winsorp Software delivered by Raschig. With the support of the present results a modified version of Winsorp has been elaborated for high liquid loads and X-Style RSP. In terms of mass transfer, the CO 2 /MDEA system was used to measure k L a e while the classic CO 2 /NaOH and SO 2 /NaOH systems were used for a e and k G a e measurements. The RSP200X was found to develop a high interfacial area compared to its geometric area. While for standard packings the gas flow rate is often considered to have only a small effect on effective area when operating below the loading point, its effect measured on RSP200X is significant and of the same order as for liquid load. Measurements of k L a and k G a further confirm these trends. [ABSTRACT FROM AUTHOR]

Gulf of Mexico versus Atlantic populations of several coastal species in the southeastern United States are known to differ sharply in genetic composition, but most transitional zones have not previously been examined in detail. Here we employ molecular markers from mitochondrial and nuclear loci to characterize cytonuclear genetic associations at meso- and microgeographic scales along an eastern Florida transitional zone between genetically distinct Atlantic and Gulf populations of the American oyster, Crassostrea virginica. The single- and multilocus cytonuclear patterns display: (1) a cline extending along 340 km of the east Florida coastline; (2) a pronounced step in the cline centered at Cape Canaveral (shifts in allelic frequencies by 50-75% over a 20 km distance); (3) a close agreement of observed genotypic frequencies with Hardy-Weinberg expectations within locales; and (4) mild or nonexistent nuclear and cytonuclear disequilibria in most local population samples. These results imply: (1) considerable restrictions to interpopulational gene flow along the eastern Florida coastline; (2) within locales, free interbreeding (as opposed to mere population admixture) between Gulf and Atlantic forms of oysters; and (3) localized population recruitment in the transition zone localities. These findings demonstrate that marine organisms with high dispersal potential via long-lived pelagic larvae can nonetheless display pronounced spatial population genetic structure, and more generally they exemplify the utility of pronounced genetic transition zones for the study of population level processes.

In recent years, the development of the Intelligent Transportation System (ITS) has increased the popularity of vehicular ad hoc networks (VANET). A VANET is designed to enable vehicles to exchange information about traffic or vehicle conditions to help other vehicles avoid traffic accidents or traffic jams. To resist malicious attacks, all vehicles must be anonymous and their routings must be untraceable, but still verifiable. The vehicles must trust each other and communicate confidentially. In a VANET, Road Side Units (RSU) are installed on traffic signs or streetlights to help vehicles maintain anonymity, to authenticate messages, or to support confidentiality. However, the coverage of an RSU is limited and the cost of widespread installation is high. RSU installations are incremental, so messages must be authenticated using dense RSUs or sparse RSUs. In this paper, the concept of random key pre-distribution that is used in Wireless Sensor Networks (WSN) is modified to random secret pre-distribution (RSP), which integrates identity-based cryptography (IBC) to produce a message authentication scheme for VANETs in a sparse RSU environment. In the proposed scheme, vehicles follow a process to determine a common secret, allowing them to authenticate each other and obtain the pairing value as a key for use in message authentication and private communication. Evaluation results show that the proposed scheme outperforms related schemes.

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Studies in environmentally controlled rooms have been used over the years to assess the impact of environmental tobacco smoke on indoor air quality. As new tobacco products are developed, it is important to determine their impact on air quality when used indoors. Before such an assessment can take place it is essential that the analytical methods used to assess indoor air quality are validated and shown to be fit for their intended purpose. Consequently, for this assessment, an environmentally controlled room was built and seven analytical methods, representing eighteen analytes, were validated. The validations were carried out with smoking machines using a matrix-based approach applying the accuracy profile procedure. The performances of the methods were compared for all three matrices under investigation: background air samples, the environmental aerosol of Tobacco Heating System THS 2.2, a heat-not-burn tobacco product developed by Philip Morris International, and the environmental tobacco smoke of a cigarette. The environmental aerosol generated by the THS 2.2 device did not have any appreciable impact on the performances of the methods. The comparison between the background and THS 2.2 environmental aerosol samples generated by smoking machines showed that only five compounds were higher when THS 2.2 was used in the environmentally controlled room. Regarding environmental tobacco smoke from cigarettes, the yields of all analytes were clearly above those obtained with the other two air sample types. Graphical abstractfx1Highlights· Selected indoor air quality methods were validated using accuracy profiles. · The impact of a novel Tobacco Heating System on these methods was assessed. · Environmental tobacco smoke and background air samples were also validated. · The methods were apt for the detection and quantification of 18 constituents in air. · Methods were applied for evaluating the impact of tobacco products on indoor air. Abbreviations [ABSTRACT FROM AUTHOR]

Staphylococcus aureus is a major bacterial pathogen, which causes severe blood and tissue infections that frequently emerge by autoinfection with asymptomatically carried nose and skin populations. However, recent studies report that bloodstream isolates differ systematically from those found in the nose and skin, exhibiting reduced toxicity toward leukocytes. In two patients, an attenuated toxicity bloodstream infection evolved from an asymptomatically carried high-toxicity nasal strain by loss-of-function mutations in the gene encoding the transcription factor repressor of surface proteins (rsp). Here, we report that rsp knockout mutants lead to global transcriptional and proteomic reprofiling, and they exhibit the greatest signal in a genome-wide screen for genes influencing S. aureus survival in human cells. This effect is likely to be mediated in part via SSR42, a long-noncoding RNA. We show that rsp controls SSR42 expression, is induced by hydrogen peroxide, and is required for normal cytotoxicity and hemolytic activity. Rsp inactivation in laboratory- and bacteremia-derived mutants attenuates toxin production, but up-regulates other immune subversion proteins and reduces lethality during experimental infection. Crucially, inactivation of rsp preserves bacterial dissemination, because it affects neither formation of deep abscesses in mice nor survival in human blood. Thus, we have identified a spontaneously evolving, attenuated-cytotoxicity, nonhemolytic S. aureus phenotype, controlled by a pleiotropic transcriptional regulator/noncoding RNA virulence regulatory system, capable of causing S. aureus bloodstream infections. Such a phenotype could promote deep infection with limited early clinical manifestations, raising concerns that bacterial evolution within the human body may contribute to severe infection. [ABSTRACT FROM AUTHOR]

In recent years, the development of the Intelligent Transportation System (ITS) has increased the popularity of vehicular ad hoc networks (VANET). A VANET is designed to enable vehicles to exchange information about traffic or vehicle conditions to help other vehicles avoid traffic accidents or traffic jams. To resist malicious attacks, all vehicles must be anonymous and their routings must be untraceable, but still verifiable. The vehicles must trust each other and communicate confidentially. In a VANET, Road Side Units (RSU) are installed on traffic signs or streetlights to help vehicles maintain anonymity, to authenticate messages, or to support confidentiality. However, the coverage of an RSU is limited and the cost of widespread installation is high. RSU installations are incremental, so messages must be authenticated using dense RSUs or sparse RSUs. In this paper, the concept of random key pre-distribution that is used in Wireless Sensor Networks (WSN) is modified to random secret pre-distribution (RSP), which integrates identity-based cryptography (IBC) to produce a message authentication scheme for VANETs in a sparse RSU environment. In the proposed scheme, vehicles follow a process to determine a common secret, allowing them to authenticate each other and obtain the pairing value as a key for use in message authentication and private communication. Evaluation results show that the proposed scheme outperforms related schemes. [ABSTRACT FROM AUTHOR]

Abstract: Rotating Shadowband Irradiometers (RSI) are frequently used for solar resource assessment at remote sites due to their significantly higher robustness for soiling, their lower power and maintenance requirements and their cheaper acquisition and operation in contrast to pyrheliometer on tracker systems. The primordial lower accuracy of their photodiode sensor, usually a LI-200 pyranometer from LI-COR Inc., is mainly caused by restrictions of their spectral sensitivity and temperature dependence. However accuracy is notably increased by application of corrections to the raw sensor response. Thus, finally a coincidence of DNI measurements from RSIs with high-precision pyrheliometer measurements within 15W/m2 (root mean square deviation for 10min averages) for actual values, less than 3% for daily DNI and within approximately 1.5% of the monthly and annual sum is reached. Within this contribution, the long-term behavior of the LI-COR sensor is examined with regard to the drift of the photodiode sensitivity. This is analyzed from recalibrations of 30 sensors after one to four years and from long-term studies lasting from one to several years. If a significant drift appears, the corresponding uncertainties can be reduced through recalculation of the previous measurement data for the total measurement campaign. Furthermore, studies about the coincidence and deviation of the responses for global, diffuse and direct irradiance of RSI measurements between several individual RSIs and to reference measurements from high-precision thermopiles are presented for different time resolutions. [Copyright &y& Elsevier]

Objective. Proton therapy after breast-conserving surgery (BCS) can substantially reduce the dose to lung and cardiac structures. However, these dosimetric benefits are subject to beam range uncertainty in patient. The conversion of the CT-Hounsfield unit (HU) into relative stopping power (RSP) is the primary contribution to range uncertainty. Hence, an accurate HU-RSP conversion is essential. Approach. Real tissue samples, including muscle and adipose, were prepared. The water equivalent path length (WEPL) of these samples was measured under homogeneous conditions using a 12-diode detector array of our time-resolved in vivo range verification system (IRVS). The HU-RSP conversion was improved using the measured WEPL and HU for adipose tissue. The measured WEPL values were compared with the treatment planning calculation results based on the stoichiometric CT-HU calibration technique. The effect was investigated for both with and without adipose tissue in HU-RSP conversion. Main results. The IRVS was calibrated based on the solid water phantom. The relative differences in WEPL (RSP) between measurements and calculations for muscle, adipose, and water was -1.19% (-0.75%), -4.25%(-4%), and -0.23%(-0.07%), respectively. Based on the improved HU-RSP conversion, the relative differences in WEPL was reduced to -0.97%(-0.62%), -1.50%(-1.46%), and -0.22% (0.00%), respectively. Significance. The WEPL deviation of adipose tissue is larger than the testing limit of 3.5% for beam range robustness in current clinical practice. However, the improved HU-RSP conversion reduced this deviation. The main component of breast tissue is adipose. Hence, the proton treatment of BCS can be undershooting if no proper measures are taken against this specific uncertainty., (© 2022 Institute of Physics and Engineering in Medicine.)