bluuebunny/crossref_metadata_2025 huggingface dataset:
The Great Moderation and the Relationship between Output Growth and Its Volatility
Authors: Fang Wen‐Shwo , Miller Stephen M.
Published: July 2021

This study examines the effect of the Great Moderation on the relationship between U.S. output growth and its volatility over the period 1947 to 2006. First, we consider the possible effects of structural changes in the volatility process. We employ generalized autoregressive conditional heteroscedasticity in mean (GARCH‐M) specifications, which describe output growth rate and its volatility with and without a one‐time structural break in volatility. Second, our data analyses and empirical results suggest no significant relationship between the output growth rate and its volatility; this favors the traditional wisdom of dichotomy in macroeconomics. Moreover, the evidence shows that the time‐varying variance falls sharply or even disappears once we incorporate a one‐time structural break in the unconditional variance of output starting in 1982 or 1984. That is, the integrated GARCH effect proves spurious. Finally, a joint test of a trend change and a one‐time shift in the volatility process finds that the one‐time shift dominates.
How Would David Ricardo Have Taught the Principle of Comparative Advantage?
Authors: Maneschi Andrea
Published: July 2021

If David Ricardo had lived beyond the age of 51, how might he have delivered a lecture on comparative advantage? I argue that Ricardo infers the direction of comparative advantage and the size of the gains from trade by interpreting the four numbers in his Principles of Political Economy and Taxation for cloth and wine traded between England and Portugal as amounts of labor embodied in the quantities actually traded. He illustrates diagrammatically the gains from trade as the overall labor that England would save if it were to liberalize wheat imports by repealing the Corn Laws. Postulating a concave production function for wheat, Ricardo also depicts the concomitant rise in the profit rate, describing it as an equally important contemporary gain from trade for England. His interpretation differs radically from the textbook versions of the “Ricardian trade model,” and suggests a more authentic way of presenting the principle of comparative advantage.
Posttraumatic stress disorder, complex PTSD and subtypes of loneliness among older adults
Authors: Fox Robert , Hyland Philip , Coogan Andrew N. , Cloitre Marylène , McHugh Power Joanna
Published: July 2021

Objectives

Research examining the relationship between loneliness and Complex Posttraumatic Stress Disorder (CPTSD) is scarce, particularly among older adults. CPTSD includes the core symptoms of PTSD along with additional symptoms reflecting “disturbances in self‐organisation” (DSO). This study examined the cross‐sectional relationships between loneliness (emotional and social loneliness) and CPTSD symptoms (i.e., PTSD and DSO symptoms) in older adults.

Methods

Structural equation modelling was used to examine these relationships in a nationally representative sample of US adults aged 60–70 years (n = 456).

Results

Controlling for covariates, emotional loneliness was associated with PTSD (β = 0.31) and DSO (β = 0.57) symptoms whereas social loneliness was only associated with DSO symptoms (β = 0.25). The model explained 35.0% of the variance in PTSD symptoms and 71.3% in DSO symptoms.

Conclusion

These findings have important implications for treating and understanding PTSD/CPTSD and their correlates among older adults.
Temperature effects on the jumping performance of house crickets
Authors: Deban Stephen M. , Anderson Christopher V.
Published: July 2021

Insect jumping and other explosive animal movements often make use of elastic‐recoil mechanisms to enhance performance. These mechanisms circumvent the intrinsic rate limitations on muscle shortening, allowing for greater power production as well as thermal robustness of the associated movements. Here we examine the performance and temperature effects on jumping in the house cricket, Acheta domesticus, using high‐speed imaging and inverse dynamics analysis. We find that adult house crickets jumped with greater performance than would be possible using direct muscle shortening, generating a peak power of over 2000 W/kg of muscle mass and maintaining high performance across the entire tested range of body temperatures (12–32°C). Performance declined at the lowest temperature (12°C), yet jump power still exceeds available muscle power. These results reveal that Acheta domesticus makes use of an elastic‐recoil mechanism that enhances both the performance and thermal robustness of jumping.
FOXO3a acetylation regulates PINK1, mitophagy, inflammasome activation in murine palmitate-conditioned and diabetic macrophages
Authors: Gupta Priya , Sharma Gaurav , Lahiri Amit , Barthwal Manoj Kumar
Published: July 2021

Nucleotide-binding oligomerization domain, leucine-rich repeat, and pyrin domain containing 3 inflammasome and mitophagy play an important role in cytokine release and diabetes progression; however, the role of saturated fatty acid that is induced under such conditions remains little explored. Therefore, the present study evaluates mechanisms regulating mitophagy and inflammasome activation in primary murine diabetic and palmitate-conditioned wild-type (WT) peritoneal macrophages. Peritoneal macrophage, from the diabetic mice and WT mice, challenged with LPS/ATP and palmitate/LPS/ATP, respectively, showed dysfunctional mitochondria as assessed by their membrane potential, mitochondrial reactive oxygen species (mtROS) production, and mitochondrial DNA (mtDNA) release. A defective mitophagy was observed in the diabetic and palmitate-conditioned macrophages stimulated with LPS/ATP as assessed by translocation of PTEN-induced kinase 1 (PINK1)/Parkin or p62 in the mitochondrial fraction. Consequently, increased apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) oligomerization, caspase-1 activation, and IL1β secretion were observed in LPS/ATP stimulated diabetic and palmitate-conditioned macrophages. LPS/ATP induced Forkhead box O3a (FOXO3a) binding to PINK1 promoter and increased PINK1 mRNA expression in WT macrophages. However, PINK1 mRNA and protein expression were significantly decreased in diabetic and palmitate-conditioned macrophages in response to LPS/ATP. Palmitate-induced acetyl CoA promoted FOXO3a acetylation, which prevented LPS/ATP-induced FOXO3a binding to the PINK1 promoter. C646 (P300 inhibitor) and SRT1720 (SIRT1 activator) prevented FOXO3a acetylation and restored FOXO3a binding to the PINK1 promoter, PINK1 mRNA expression, and mitophagy in palmitate-conditioned macrophages treated with LPS/ATP. Also, a significant decrease in the LPS/ATP-induced mtROS production, mtDNA release, ASC oligomerization, caspase-1 activation, and IL-1β release was observed in the palmitate-conditioned macrophages. Similarly, modulation of FOXO3a acetylation also prevented LPS/ATP-induced mtDNA release and inflammasome activation in diabetic macrophages. Therefore, FOXO3a acetylation regulates PINK1-dependent mitophagy and inflammasome activation in the palmitate-conditioned and diabetic macrophages.
Hybrid transmission expansion planning and reactive power planning considering the real network uncertainties
Authors: Abdi Hamdi , Moradi Mansour , Rashidi Reza
Published: July 2021

Conventional transmission expansion planning (TEP) has evolved with the increasing influence of distributed generations (DGs) and electric vehicles (EVs). This increases uncertainty in power systems. On the other hand, reactive power plays a key role in voltage stability, so modeling reactive power planning in TEP is very important. The amount of reactive power is a determining factor regarding the stability of the network voltage and in case of shortage, occurrence of some events may endanger the voltage stability. This research aims at proposing a hybrid TEP and reactive power planning for the first time. Furthermore, the impact of wind, PV power plants, and EVs, as the common sources of uncertainties, are included. The ultimate goal of HTEP‐RPP is to find the transmission line candidates that meet the reactive power requirements. The simulation case studies on IEEE 24‐ and 118‐ buses confirm that the TEP based on DCPF may lead to some unreliable operating conditions due to violating the voltage constraints. In this case, the HTEP‐RPP results, by applying the imperialist competitive algorithm (ICA), are more comprehensive and effective than the results obtained by gravitational search algorithm (GSA), for the studied problem or even the popular TEP solutions.
Articular cartilage thickness changes differ between males and females 4 years following anterior cruciate ligament reconstruction
Authors: Pius Alexa K. , Beynnon Bruce D. , Fiorentino Niccolo , Gardner‐Morse Mack , Vacek Pamela M. , DeSarno Mike , Failla Mat , Slauterbeck James R. , Sturnick Daniel R. , Argentieri Erin C. , Tourville Timothy W.
Published: July 2021

Anterior cruciate ligament injury and reconstruction (ACLR) affects articular cartilage thickness profiles about the tibial, femoral, and patellar surfaces; however, it's unclear whether the magnitudes of change in cartilage thickness, as well as the locations and areas over which these changes occur, differ between males and females. This is important to consider as differences exist between the sexes with regard to knee biomechanics, patellofemoral pain, and anatomic alignment, which influence risk of an index and repeated injury. Subjects underwent ACLR with a bone‐patella tendon‐bone autograft. At 4‐year follow‐up, they had asymptomatic knees; however, significant ACL injured‐to‐contralateral normal knee differences in articular cartilage thickness values were observed. Both thickening and thinning of cartilage occurred about the tibiofemoral and patellofemoral joints, relative to matched control subjects with normal knees. Further, the location of the areas and magnitudes of thickening and thinning were different between females and males. Thickening (swelling) of articular cartilage is an early finding associated with the onset of posttraumatic osteoarthritis (PTOA). Therefore, the increases in cartilage thickness that were observed in this cohort may represent early signs of the onset of PTOA that occur prior to the patient developing symptoms and radiographic evidence of this disease. The different locations of areas that underwent a change in cartilage thicknesses between males and females suggest that each sex responds differently to knee ligament trauma, reconstruction, rehabilitation, and return to activity, and indicates that sex‐specific analysis should be utilized in studies of PTOA.
Development of magnetism‐assisted in‐tube solid phase microextraction of phenolic acids in fruit juices prior to high‐performance liquid chromatography quantification
Authors: Chen Hexun , Song Xiaochong , Huang Xiaojia
Published: July 2021

Magnetism‐assisted in‐tube solid phase microextraction based on porous monolith mingled with Fe3O4 nanoparticles was developed for capture of phenolic acids in fruit juices. First, poly (1‐allyl‐3‐methylimidazolium bis [(trifluoro methyl) sulfonyl] imide‐co‐ethylene dimethacrylate) monolith embedded with Fe3O4 nanoparticles was facile fabrication in a capillary and employed as microextraction column. Subsequently, a magnetic coil adopted to produce variable magnetic fields during extraction stage was twined on the microextraction column. The analytes contents in eluant were quantified by high performance liquid chromatogram with diode array detector. Various parameters affecting the extraction performance were inspected and optimized in detail. Results revealed that the exertion of magnetic fields in adsorption and desorption steps enhanced the extraction efficiencies of analytes from 44.9–64.0% to 78.6–87.1%. Under the optimal extraction factors, the limits of detection were between 0.012 and 0.061 μg/L, relative standard deviations for precision in terms of intra‐ and inter‐day assay variability ranged from 1.9 to 9.8%. The introduced approach was successfully applied to simultaneously quantify the contents of five analytes in real fruit juices with satisfying fortified recoveries (80.1–116%). The obtained results well demonstrate the promising potential of the developed method in the highly sensitive quantification of trace phenolic acids in complex samples.
Correlations Between Olfactory Psychophysical Scores and SARS‐CoV‐2 Viral Load in COVID‐19 Patients
Authors: Vaira Luigi Angelo , Deiana Giovanna , Lechien Jerome R. , De Vito Andrea , Cossu Andrea , Dettori Marco , Del Rio Arcadia , Saussez Sven , Madeddu Giordano , Babudieri Sergio , Fois Alessandro G. , Cocuzza Clementina , Hopkins Claire , De Riu Giacomo , Piana Andrea Fausto
Published: July 2021

Objectives/Hypothesis

The aim of this study was to evaluate the correlations between the severity and duration of olfactory dysfunctions (OD), assessed with psychophysical tests, and the viral load on the rhino‐pharyngeal swab determined with a direct method, in patients affected by coronavirus disease 2019 (COVID‐19).

Study design

Prospective cohort study.

Methods

Patients underwent psychophysical olfactory assessment with Connecticut Chemosensory Clinical Research Center test and determination of the normalized viral load on nasopharyngeal swab within 10 days of the clinical onset of COVID‐19.

Results

Sixty COVID‐19 patients were included in this study. On psychophysical testing, 12 patients (20% of the cohort) presented with anosmia, 11 (18.3%) severe hyposmia, 13 (18.3%) moderate hyposmia, and 10 (16.7%) mild hyposmia with an overall prevalence of OD of 76.7%. The overall median olfactory score was 50 (interquartile range [IQR] 30–72.5) with no significant differences between clinical severity subgroups. The median normalized viral load detected in the series was 2.56E+06 viral copies/106 copies of human beta‐2microglobulin mRNA present in the sample (IQR 3.17E+04–1.58E+07) without any significant correlations with COVID‐19 severity. The correlation between viral load and olfactory scores at baseline (R2 = 0.0007; P = .844) and 60‐day follow‐up (R2 = 0.0077; P = .519) was weak and not significant.

Conclusions

The presence of OD does not seem to be useful in identifying subjects at risk for being super‐spreaders or who is at risk of developing long‐term OD. Similarly, the pathogenesis of OD is probably related to individual factors rather than to viral load and activity.

Level of Evidence

4 Laryngoscope, 131:2312–2318, 2021
Creepiness: Its antecedents and impact on loyalty when interacting with a chatbot
Authors: Rajaobelina Lova , Prom Tep Sandrine , Arcand Manon , Ricard Line
Published: July 2021

Consumers sometimes describe their experience of interacting with artificial intelligence‐based human‐like chatbots as creepy. This study investigates the antecedents of creepiness (i.e., the chatbot's usability, privacy concerns, and user variables such as technology anxiety and the need for human interaction) and its impact on consumer loyalty. Grounded in the technology paradox, it deepens the understanding of creepiness in light of the theoretical underpinnings of the privacy paradox and privacy cynicism. Presented with the task of obtaining a car insurance quote, 430 consumers participated in a simulation involving interaction with a chatbot, followed by a questionnaire. The findings show that creepiness decreases loyalty and indirectly impacts it through trust and negative emotions. While usability reduces perceptions of creepiness, privacy concerns raised by the interaction with the chatbot increase creepiness, which is positively associated with consumer traits (i.e., technology anxiety and need for human interaction). The main contribution of the research lies in its focus on creepiness, a concept under‐researched in the marketing literature, and which can be seen from the perspective of a coping mechanism for consumers’ privacy concerns. This paper provides practical implications to orient managers in the design and implementation of chatbots, as a promising touch point to build customer loyalty.
Natural History of Polymerase Gamma–Related Ataxia
Authors: Bender Friedemann , Timmann Dagmar , van de Warrenburg Bart P. , Adarmes‐Gómez Astrid D. , Bender Benjamin , Thieme Andreas , Synofzik Matthis , Schöls Ludger
Published: July 2021

Background

Mutations in the mitochondrial DNA polymerase gamma are causing a wide phenotypic spectrum including ataxia as one of the most common presentations.

Objective

The objective of this study was to determine the course of disease of polymerase gamma–related ataxia.

Methods

In a prospective natural history study, we assessed 24 adult ataxia patients with biallelic polymerase gamma mutations for (1) severity of cerebellar dysfunction using the Scale for the Assessment and Rating of Ataxia score, (2) presence of nonataxia signs using the Inventory of Non‐Ataxia Symptoms, (3) gray‐ and white‐matter changes in brain MRI, and (4) findings in nerve conduction studies.

Results

Assessment included follow‐up visits up to 11.6 years. The Scale for the Assessment and Rating of Ataxia showed a mean annual increase of 1.02 ± 0.78 points/year. Disease progression was faster in patients with age at onset ≤ 30 years (1.5 Scale for the Assessment and Rating of Ataxia points/year) than with later onset (0.5 points/year); P = 0.008. The Inventory of Non‐Ataxia Symptoms count increased by 0.30 ± 0.4 points/year. External ophthalmoplegia, brain stem oculomotor signs, areflexia, and sensory deficits were the most common nonataxic features. On MRI cerebellar atrophy was mild. T2 signal alterations affected mostly cerebellar white matter, middle cerebellar peduncles, thalamus, brain stem, and occipital and frontal white matter. Within 4 years, progression was primarily observed in the context of repeated epileptic seizures. Nerve conduction studies revealed axonal sensory peripheral neuropathy with mild motor nerve involvement. Exploratory sample size calculation implied 38 patients per arm as sufficient to detect a reduction of progression by 50% in hypothetical interventions within a 1‐year trial.

Conclusion

The results recommend the Scale for the Assessment and Rating of Ataxia as a primary outcome measure for future interventional trials in polymerase gamma–related ataxia. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society
A circularly polarized low‐profile magnetoelectric dipole antenna
Authors: Wu Siyu , Zhao Jianping , Xu Juan
Published: July 2021

In this article, we proposed a novel circularly polarized magnetoelectric (ME) dipole antenna with low profile, which is excited by substrate integrated waveguide aperture‐coupled feeding structure with a butterfly‐shaped slot. The ME dipole antenna is formed of a couple of oblong metallic patches with square corner cutting off and elliptic perturbation acting as electric dipole, and two couples of vertical metalized via holes working as magnetic dipole. The profile of the antenna is 0.122λ0. The antenna achieves a fractional bandwidth of 32.6% for |S11| smaller than −10 dB from 22.6 to 31.3 GHz and the 3‐dB axial‐ratio bandwidth (BW) of 12.8% from 22.6 to 25.7 GHz. Moreover, the gain is maintained over 6 dB for a large portion of the operational BW. The measured boresight gain is 7.8 dB.
Feasibility of diffusion weighting with a local inside‐out nonlinear gradient coil for prostate MRI
Authors: Hoque Bhuiyan Enamul , Dewdney Andrew , Weinreb Jeffrey , Galiana Gigi
Published: July 2021

Purpose

Prostate cancer remains the second leading cancer killer of men, yet it is also a disease with a high rate of overtreatment. Diffusion‐weighted imaging (DWI) has shown promise as a reliable, grade‐sensitive imaging method, but it is limited by low image quality. Currently, DWI quality image is directly related to low gradient amplitudes, since weak gradients must be compensated with long echo times.

Methods

We propose a new type of MRI accessory, an “inside‐out” and nonlinear gradient, whose sole purpose is to deliver diffusion encoding to a region of interest. Performance was simulated in OPERA and the resulting fields were used to simulate DWI with two‐compartment and kurtosis models. Experiments with a nonlinear head gradient prove the accuracy of DWI and apparent diffusion coefficient (ADC) maps encoded with nonlinear gradients.

Results

Simulations validated thermal and mechanical safety while showing a 5‐ to 10‐fold increase in gradient strength over prostate. With these strengths, lesion contrast to noise ratio in ADC maps approximately doubled for a range of anatomical positions. Proof‐of‐principle experiments show that spatially varying b‐values can be corrected for accurate DWI and ADC.

Conclusions

Dedicated nonlinear diffusion encoding hardware could improve prostate DWI.
Radiation shielding and safety implications following linac conversion to an electron FLASH‐RT unit
Authors: Poirier Yannick , Mossahebi Sina , Becker Stewart J. , Koger Brandon , Xu Junliang , Lamichhane Narrotam , Maxim Peter G. , Sawant Amit
Published: July 2021

Purpose

Due to their finite range, electrons are typically ignored when calculating shielding requirements in megavoltage energy linear accelerator vaults. However, the assumption that 16 MeV electrons need not be considered does not hold when operated at FLASH‐RT dose rates (~200× clinical dose rate), where dose rate from bremsstrahlung photons is an order of magnitude higher than that from an 18 MV beam for which shielding was designed. We investigate the shielding and radiation protection impact of converting a Varian 21EX linac to FLASH‐RT dose rates.

Methods

We performed a radiation survey in all occupied areas using a Fluke Biomedical Inovision 451P survey meter and a Wide Energy Neutron Detection Instrument (Wendi)‐2 FHT 762 neutron detector. The dose rate from activated linac components following a 1.8‐min FLASH‐RT delivery was also measured.

Results

When operated at a gantry angle of 180° such as during biology experiments, the 16 MeV FLASH‐RT electrons deliver ~10 µSv/h in the controlled areas and 780 µSv/h in the uncontrolled areas, which is above the 20 µSv in any 1‐h USNRC limit. However, to exceed 20 µSv, the unit must be operated continuously for 92 s, which corresponds in this bunker and FLASH‐RT beam to a 3180 Gy workload at isocenter, which would be unfeasible to deliver within that timeframe due to experimental logistics. While beam steering and dosimetry activities can require workloads of that magnitude, during these activities, the gantry is positioned at 0° and the dose rate in the uncontrolled area becomes undetectable. Likewise, neutron activation of linac components can reach 25 µSv/h near the isocenter following FLASH‐RT delivery, but dissipates within minutes, and total doses within an hour are below 20 µSv.

Conclusion

Bremsstrahlung photons created by a 16 MeV FLASH‐RT electron beam resulted in consequential dose rates in controlled and uncontrolled areas, and from activated linac components in the vault. While our linac vault shielding proved sufficient, other investigators would be prudent to confirm the adequacy of their radiation safety program, particularly if operating in vaults designed for 6 MV.
Heart‐centered positioning and tailored beam‐shaping filtration for reduced radiation dose in coronary artery calcium imaging: A Multi‐Ethnic Study of Atherosclerosis (MESA) Study
Authors: Colvert Brendan , Rigolli Marzia , Craine Amanda , Criqui Michael , Contijoch Francisco
Published: July 2021

Purpose

Cardiac computed tomography has a clear clinical role in the evaluation of coronary artery disease and assessment of coronary artery calcium (CAC) but the use of ionizing radiation limits the clinical use. Beam‐shaping “bow‐tie” filters determine the radiation dose and the effective scan field‐of‐view diameter (SFOV) by delivering higher X‐ray fluence to a region centered at the isocenter. A method for positioning the heart near the isocenter could enable reduced SFOV imaging and reduce dose in cardiac scans. However, a predictive approach to center the heart, the extent to which heart centering can reduce the SFOV, and the associated dose reductions have not been assessed. The purpose of this study is to build a heart‐centered patient positioning model, to test whether it reduces the SFOV required for accurate CAC scoring, and to quantify the associated reduction in radiation dose.

Methods

The location of 38,184 calcium lesions (3151 studies) in the Multi‐Ethnic Study of Atherosclerosis was utilized to build a predictive heart‐centered positioning model and compare the impact of SFOV on CAC scoring accuracy in heart‐centered and conventional body‐centered scanning. Then, the positioning model was applied retrospectively to an independent, contemporary cohort of 118 individuals (81 with CAC > 0) at our institution to validate the model's ability to maintain CAC accuracy while reducing the SFOV. In these patients, the reduction in dose associated with a reduced SFOV beam‐shaping filter was quantified.

Results

Heart centering reduced the SFOV diameter 25.7% relative to body centering while maintaining high CAC scoring accuracy (0.82% risk reclassification rate). In our validation cohort, imaging at this reduced SFOV with heart‐centered positioning and tailored beam‐shaping filtration led to a 26.9% median dose reduction (25–75th percentile: 21.6%–29.8%) without any calcium risk reclassification.

Conclusions

Heart‐centered patient positioning enables a significant radiation dose reduction while maintaining CAC accuracy.
H‐scan trajectories indicate the progression of specific diseases
Authors: Baek Jihye , Parker Kevin J.
Published: July 2021

Purpose

The ability of ultrasound to assess pathology is increasing with the development of quantitative parameters. Among these are a set of parameters derived from the recent H‐scan analysis of subresolvable scattering. The emergence of these quantitative measures of tissue/ultrasound interactions now enables a study of the unique trajectories of multiparametric features in multidimensional space, representing the progression of specific diseases over time. We develop the mathematical and visual tools that are effective for classifying, quantifying, and visualizing the steady progression of several diseases from independent studies, all within a uniform framework.

Methods

After applying the H‐scan analysis of ultrasound echoes, we trained a support vector machine (SVM) to classify the unique trajectories of progressive liver disease from fibrosis, steatosis, and pancreatic ductal adenocarcinoma (PDAC) metastasis. Our approaches include the development of trajectory maps and disease‐specific color imaging stains.

Results

The multidimensional SVM image classification reached 100% accuracy across the three different studies.

Conclusion

H‐scan trajectories can be useful to track the progression of multiple classes of diseases, improving diagnosis, staging, and assessing the response to therapy.
Assessment of multi‐energy inter‐pixel coincidence counters for photon‐counting detectors at the presence of charge sharing and pulse pileup: A simulation study
Authors: Taguchi Katsuyuki , Iwanczyk Jan S.
Published: July 2021

Purpose

Spectral distortion due to charge sharing (CS) and pulse pileup (PP) in photon‐counting detectors (PCDs) degrades the quality of PCD data. We recently proposed multi‐energy inter‐pixel coincidence counters (MEICC) that provided spectral cross‐talk information related to CS. When PP was absent, the normalized Cramér–Rao lower bounds (nCRLBs) of 225‐µm pixel PCDs with MEICC was comparable to those of 450‐µm pixel PCD without MEICC. The aim of this study was to assess the performance of PCDs with MEICC in the presence of both CS and PP using computer simulations.

Methods

An in‐house Monte Carlo program was modified to incorporate the following four temporal elements: (1) A pulse shape with a pulse duration of 20 ns, (2) delays of up to 10 ns in anode arrival times when photons were incident on pixel boundaries, (3) offsets proportional to a vertical separation between the primary and secondary charge clouds at the rate of ±4 ns per ±100 µm, and (4) a stochastic fluctuation of anode arrival times for all of the charge clouds with a standard deviation of 2 ns. We assessed the performance of five PCDs, (a)–(f), for three spectral tasks, (A)–(C): (a) The conventional PCD, (b) a PCD with MEICC, (c) a PCD with one coincidence counter (1CC), (d) a PCD with a 3 × 3 analog charge summing scheme (ACS), and (e) a PCD with a 3 × 3 digital count summing scheme (DCS); (A) conventional CT imaging with water (i.e., linear attenuation coefficient maps), (B) water–bone material decomposition, and (C) K‐edge imaging with tungsten. The tube current was changed from 1 mA to 1000 mA and the nCRLB was assessed.

Results

The recorded count rate curves were fitted by the non‐paralyzable detection model with the effective deadtime parameter. The best fit was achieved by 25.8 ns for the conventional PCD, 18.6 ns for MEICC and 1CC, 140.5 ns for ACS, and 209.0 ns for DCS. The nCRLBs were strongly dependent on count rates. MEICC provided the best nCRLBs for all of the imaging tasks over the count rate range investigated except for a few conditions such as K‐edge imaging at 1 mA. PP decreased the merit of MEICC over the conventional PCD in addressing CS. Nonetheless, MEICC consistently provided better nCRLBs than the conventional PCD did. The nCRLBs of MEICC were in the range of 49–58% of those of the conventional PCD for K‐edge imaging, 45–76% for water–bone material decomposition, and 81–88% for the conventional CT imaging (i.e., linear attenuation coefficient maps). ACS provided better nCRLBs than the conventional PCD did only when the effect of PP was minor (e.g., when the counting efficiency of the conventional PCD was higher than 0.95 with the tube current of up to 100 mA).

Conclusion

Besides a few cases, MEICC provides the best nCRLBs for all of the tasks at all of the count rates. ACS and DCS provide better nCRLBs than the conventional PCD does only when count rates are very low.
Electronic charting of radiation therapy planning and treatment: Report of Task Group 262
Authors: Mechalakos James G. , Dieterich Sonja , Fong de los Santos Luis E. , Fontenla Sandra C. , Hanley Joseph , Harwalkar Vijay A. , Hong Linda X. , Huang Y. Jessica , Kim Grace Gwe‐Ya , Richardson Susan L. , Sutlief Steven G. , Yaddanapudi Sridhar , Merkel Sue , Parry Mark
Published: July 2021

While most Radiation Oncology clinics have adopted electronic charting in one form or another, no consensus document exists that provides guidelines for safe and effective use of the Radiation Oncology electronic medical records (RO‐EMR). Task Group 262 was formed to provide these guidelines as well as to provide recommendations to vendors for improving electronic charting functionality in future. Guidelines are provided in the following areas: Implementation and training for the RO‐EMR, acceptance testing and quality assurance (QA) of the RO‐EMR, use of the RO‐EMR as an information repository, use of the RO‐EMR as a workflow manager, electronic charting for brachytherapy and nonstandard treatments, and information technology (IT) considerations associated with the RO‐EMR. The report was based on a literature search by the task group, an extensive survey of task group members on their respective RO‐EMR practices, an AAPM membership survey on electronic charting, as well as group consensus.
The Abundance and Distribution of Hatchery and Naturally Produced Chinook Salmon in Columbia River Estuary Nearshore Habitat
Authors: Bottom Daniel L. , Hinton Susan A. , Teel David J. , Curtis Roegner G. , Johnson Lyndal L. , Sandford Benjamin P.
Published: July 2021

Columbia River hatcheries release millions of juvenile Chinook Salmon Oncorhynchus tshawytscha to support fisheries and mitigate for historical productivity declines from dam construction and upriver habitat losses. Recent federal biological opinions for Federal Columbia River Power System operations also have mandated restoration of estuarine rearing habitats to mitigate for mortality of naturally produced (NP) salmon at main-stem dams. We compared genetic stock compositions, distributions, abundances, and length frequencies of hatchery-marked and unmarked Chinook Salmon to evaluate the extent of hatchery influence on nearshore estuarine habitat use and the potential for interactions between hatchery-origin (HO) and NP salmon. Cumulative Chinook Salmon releases from all hatcheries in 2010 and 2011 dictated estuarine stock composition, abundance, and life histories during the spring–summer migration peak. Naturally produced salmon from the lower Columbia River populations, including many fry migrants, were most abundant, but larger HO juveniles also frequented nearshore sites, where their total biomass often equaled or exceeded that of NP fish. Large releases of a single stock of origin (Spring Creek Group fall run) in April and May created sharp pulses in the estuary entry timing of fingerling-sized salmon and dominated abundance and stock composition at some sites. Successive releases from scores of hatcheries during spring and early summer ensured a consistent presence of HO salmon near shore, regardless of the habitat-specific residence times of individual fish. Overall, the historical replacement of diverse wild populations with fewer hatchery stocks of a narrow size range and migration timing has intensified nearshore habitat use during the spring–summer migration peak and reduced life history variation of Columbia River Chinook Salmon. Such changes could undermine the fish conservation goals of both hatchery mitigation and estuary restoration programs.
Safety, tolerability, and efficacy of LiRIS 400 mg in women with interstitial cystitis/bladder pain syndrome with or without Hunner lesions
Authors: Evans Robert , Kohan Alfred , Moldwin Robert , Radecki Daniel , Geib Till , Peters Kenneth M.
Published: July 2021

Aims

Two phase 2 studies were conducted to assess the efficacy and safety of lidocaine‐releasing intravesical system (LiRIS) in patients with interstitial cystitis/bladder pain syndrome (IC/BPS) with (Study 001; NCT02395042) or without, (Study 002; NCT02411110) Hunner lesions (HL).

Methods

Both were multicenter, randomized, double‐blind, placebo‐controlled, and enrolled women aged ≥18 years. In Study 001, patients were randomized 2:1:1 to LiRIS 400 mg/LiRIS 400 mg, placebo/LiRIS 400 mg, or placebo/placebo for a continuous 28 (2 × 14)‐day period. In Study 002, patients were randomized 1:1 to LiRIS 400 mg or placebo for a continuous (single treatment) 14‐day period.

Results

In total, 59 and 131 patients received treatment in Studies 001 and 002, respectively. There was no statistically significant difference in the primary endpoint, the change from baseline to Week 4 of follow‐up post‐removal in mean daily average bladder numeric rating scale (NRS) pain score in either study (Study 001: placebo/placebo, −1.6; LiRIS/LiRIS, −2.7, p = 0.142; placebo/LiRIS, −2.5, p = 0.319; Study 002: LiRIS −1.2; placebo, −1.5, p = 0.505). There was no statistically significant difference between groups in daily worst NRS pain score, number of micturitions/day or urgency episodes/day. There was no clear trend for reduction in number of HL for LiRIS vs placebo. The frequency of treatment‐emergent adverse events was similar between treatment groups in both studies; most were mild or moderate intensity.

Conclusion

These studies did not demonstrate a treatment effect of LiRIS 400 mg compared with placebo, either in patients with IC/BPS with HL, or in those without HL.
Explicit structural topology optimization using boundary element method‐based moving morphable void approach
Authors: Zhang Weisheng , Jiang Qingqing , Feng Weizhe , Youn Sung‐Kie , Guo Xu
Published: July 2021

This article presents an explicit topology optimization approach using boundary element method based moving morphable void (MMV). Structural analysis in the conventional MMV approach is performed on a fixed mesh over the entire design domain. However, in the proposed method structural boundaries are described using B‐splines and discretized with boundary elements making explicit representation of the boundaries possible. In this regard, the proposed approach has following merits: a) the use of weak material, which is often adopted to mimic voids can be completely avoided; b) exact and explicit description of voids in MMV allows the capture of tiny structural features in a robust and effective way; c) numerical instabilities stemming from the use of fixed meshes can be naturally avoided. Several numerical examples are provided to demonstrate the effectiveness of the proposed approach.
Combining dynamic XFEM with machine learning for detection of multiple flaws
Authors: Jiang Shouyan , Zhao Linxin , Du Chengbin
Published: July 2021

A novel methodology for multiple flaw detection is presented in this study. It combines the dynamic extended finite element method (XFEM) with machine learning for the first time. The extreme learning machine (ELM) is chosen as a learning rule for modeling and prediction. The XFEM is employed to overcome the issues associated with the large quantity of input data required for ELM network training, whereas the ELM itself is used to bypass the time‐consuming repeated analyses ordinarily required for the detection of multiple flaws. A large amount of potential flaw data for a structure is quasi‐randomly generated by a Sobol sequence. For each effective flaw datum, the dynamic XFEM with circular/elliptical void enrichment is used to compute the structural dynamic characteristics (i.e., frequencies and displacement mode shapes), which is possible because re‐meshing is not required for each flaw. The available data generated from the results of XFEM analyses are used for ELM network training. According to the measured dynamic characteristics, the trained ELM is then utilized to predict the size and location of flaws. The results show that the proposed novel methodology can identify accurately the location and size of circular or elliptical structural flaws. The method also is more efficient than previously proposed approaches, as it can avoid time‐consuming iterative analyses, and it is robust against noise.
SARS‐CoV‐2 in children with cancer in Brazil: Results of a multicenter national registry
Authors: Corso Mariana Cristina M. , Soares Victor J. , Amorim Anna Maria P. , Cipolotti Rosana , Magalhães Isis Maria Q. , Lins Mecneide M. , Forsait Silvana , Silva Luciana N. , de Sousa Ana Virginia L. , Alves Nádia G. , do Prado Seila I. , Silva Klerize Anecely S. , Carbone Edna K. , Brumatti Melina , Santiago Pablo , Pereira Kaline Maria M.O. , Carlesse Fabianne A.M.C. , Aguiar Marina G. , Marques Rebeca F. , Rechenmacher Ciliana , Daudt Liane E. , Michalowski Mariana B.
Published: July 2021

Background

Strategies to mitigate the impact of COVID‐19 in special populations are complex and challenging. Few studies have addressed the impact of COVID‐19 on pediatric patients with cancer in low‐ and middle‐income countries.

Methods

Multicenter observational cohort study with prospective records and retrospective analyses starting in April 2020 in 21 pediatric oncology centers distributed throughout Brazil. Participants: Patients under 18 years of age who are infected by the SARS‐CoV‐2 virus (confirmed diagnosis through reverse transcriptase‐polymerase chain reaction [RT‐PCR]) while under treatment at pediatric oncology centers. The variables of interest included clinical symptoms, diagnostic and therapeutic measures. The repercussions of SARS‐CoV‐2 infection on cancer treatment and general prognosis were monitored.

Results

One hundred seventy‐nine patients were included (median age 6 [4–13] years, 58% male). Of these, 55.9% had acute leukemia and 34.1% had solid tumors. The presence of SARS‐CoV‐2 was diagnosed by RT‐PCR. Various laboratory markers were analyzed, but showed no correlation with outcome. Children with low or high BMI for age had lower overall survival (71.4% and 82.6%, respectively) than those with age‐appropriate BMI (92.7%) (p = .007). The severity of presentation at diagnosis was significantly associated with outcome (p < .001). Overall mortality in the presence of infection was 12.3% (n = 22).

Conclusion

In children with cancer and COVID‐19, lower BMI was associated with worse prognosis. The mortality in this group of patients (12.3%) was significantly higher than that described in the pediatric population overall (∼1%).
Natural history of an immediately detectable PSA following radical prostatectomy in a contemporary cohort
Authors: Lonergan Peter E. , Cowan Janet E. , Washington Samuel L. , Greenberg Scott A. , Nguyen Hao G. , Carroll Peter R.
Published: July 2021

Background

A detectable prostate‐specific antigen (PSA) following radical prostatectomy (RP) is an unfavorable prognostic factor. However, not all men with a detectable PSA experience recurrence. We describe the natural history and outcomes in men with a detectable PSA following RP in a contemporary cohort.

Methods

A retrospective analysis of men who underwent RP for non‐metastatic prostate cancer at the University of California, San Francisco from 2000 to 2020 was performed. A detectable PSA was defined as PSA ≥ 0.03 ng/ml within 6 months of RP. Cox regression models tested the effect of detectable PSA on the development of metastasis, prostate cancer‐specific mortality, and overall survival.

Results

We identified 2941 men who had RP with 408 (13.9%) with a detectable PSA within the first 6 months. The median follow‐up was 4.42 years (interquartile range [IQR], 2.58–8.00). In total, 296 (72.5%) men with a detectable PSA had salvage treatment at a median of 6 months (IQR, 4–11). One hundred sixteen of these men had PSA failure after salvage treatment at a median of 2.0 years (IQR, 0.7–3.8). On multivariable Cox regression, the risk of development of metastasis (hazard ratio [HR], 1.05; 95% confidence interval [CI], 1.01–1.09; p = .01), prostate cancer‐specific mortality (HR, 1.13; 95% CI, 1.05–1.21; p = .0005), and overall mortality (HR, 1.07; 95% CI, 1.03–1.12; p = .002) was associated with PSA velocity after salvage treatment in men with a detectable PSA.

Conclusions

Men with a detectable PSA after RP may have excellent long‐term outcomes. PSA velocity after salvage treatment may be an important predictor for the development of metastasis, prostate cancer‐specific mortality, and overall mortality.
Evaluation of model refinement in CASP14
Authors: Simpkin Adam J. , Sánchez Rodríguez Filomeno , Mesdaghi Shahram , Kryshtafovych Andriy , Rigden Daniel J.
Published: July 2021

We report here an assessment of the model refinement category of the 14th round of Critical Assessment of Structure Prediction (CASP14). As before, predictors submitted up to five ranked refinements, along with associated residue‐level error estimates, for targets that had a wide range of starting quality. The ability of groups to accurately rank their submissions and to predict coordinate error varied widely. Overall, only four groups out‐performed a “naïve predictor” corresponding to the resubmission of the starting model. Among the top groups, there are interesting differences of approach and in the spread of improvements seen: some methods are more conservative, others more adventurous. Some targets were “double‐barreled” for which predictors were offered a high‐quality AlphaFold 2 (AF2)‐derived prediction alongside another of lower quality. The AF2‐derived models were largely unimprovable, many of their apparent errors being found to reside at domain and, especially, crystal lattice contacts. Refinement is shown to have a mixed impact overall on structure‐based function annotation methods to predict nucleic acid binding, spot catalytic sites, and dock protein structures.
My lessons for process safety leadership
Authors: Kerin Trish
Published: July 2021

Leadership is a vital component in achieving a good safety outcome, whether it be personal or process safety related. What does good leadership in process safety look like? Showing the vision and taking people on the journey is key but taking people along with you on the journey requires effective communication. An effective way of communicating lessons is via the art of storytelling; after all, this is how we teach children life lessons. In process safety, it also requires a consistent and deliberate focus on the functional aspects of process safety: knowledge and competence, engineering and design, systems and procedures, assurance, human factors and culture. Demonstration of positive leadership in these areas provides people in an organization with an established path to follow, resulting in their own performance reflecting that of the leader. In this article, I will share my lessons for process safety leadership by using the art of storytelling, in the words of Theodor Geisel, better known as Dr Seuss.
Pyramid Formation by Etching of InxGa1−xN/GaN Quantum Well Structures Grown on N‐face GaN for Nanooptical Light Emitters
Authors: Rossow Uwe , Sidikejiang Shawutijiang , Hagag Samar , Horenburg Philipp , Farr Philipp , de Vasconcellos Lourenco Rodrigo , Bremers Heiko , Hangleiter Andreas
Published: July 2021

While growth processes of /GaN quantum well (QW) structures on the Ga face of GaN buffer layers are already optimized to obtain high quantum efficiency, the growth on N‐face has gained momentum only in the past years. Compared with Ga face layers are more stable on N face, and the surface can easily be structured by wet chemical etching, which usually leads to the formation of pyramids on the surface. This allows a new way to realize nanooptical light emitters, which offers the possibility to produce structures with similar emission properties. First, /GaN (single or multi‐) QW structures on N‐face GaN are grown. In a second step, pyramids are formed by KOH etching. Pyramids with smooth side facets of the type are demonstrated and sharp tips in the nanometer range can be achieved without any sign of damage. Transmission electron microscopy (TEM) reveals that quantum dot‐like structures are present in the pyramids and in photoluminescence narrow emission lines are observed. The etching process depends on electrolyte composition and temperature, defects at the surface, and surface morphology. A better control of this process is required to achieve reproducible nanostructures.
New implementation of spin‐orbit coupling calculation on multi‐configuration electron correlation theory
Authors: Zhou Qianlong , Suo Bingbing
Published: July 2021

For treating both relativistic effect and electron correlation, the spin‐free exact two‐component and spin‐dependent first‐order Douglas–Kroll–Hess Hamiltonian and the state‐interaction (SI) method are combined to calculate the spin‐orbit coupling (SOC) on multi‐configuration electron correlation theory. In this method, SOC is evaluated via SI over electronic states from the complete active space self‐consistent field calculation, and dynamic correlation can be reckoned with the high‐level multi‐reference electron correlation theory. Work equations to calculate SOC matrix elements over Gelfand states in the framework of the graphic unitary group approach are presented. Benchmark calculations have verified the validity of the implementation. As a pilot application, the internally contracted multi‐reference configuration interaction with the inclusion of SOC via the SI approach produces reasonable equilibrium bond length and harmonic vibrational frequency of the ground state of AuO, as well as the transition energy of .