bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of Revised National Tuberculosis Control Program among Ten Designated Microscopy Centers of West Tripura: A Cross-Sectional Study
Authors: Goyal Ankita , Kumar Aman , Vashishth Tuhin , Kumari Priyanka , Pachauri Rajat K.
Published: November 2022

Objectives

Pulmonary tuberculosis (TB) is chronic communicable bacterial disease caused by Mycobacterium tuberculosis. The objective was to assess the performance in terms of knowledge and practice of pulmonary tuberculosis (PTB) program among directly observed treatment short course (DOTS) provider, lab technician, senior treatment supervisor (STS), senior tuberculosis laboratory supervisor (STLS), factors affecting knowledge and practice of PTB program, rate of detection, cure rate and to identify the gaps and underlying contributing factors in terms of supply, manpower, and infrastructure.

Materials and Methods

A cross-sectional study was conducted on knowledge and practice of PTB program among DOTS Provider, lab technician, STS, STLS in ten designated tuberculosis center of West Tripura from May 2018 to April 2019. Simple random sampling method was followed for selecting DOTS provider and sample size of 50 was taken.

Results

Majority (40.0%) of patients were in the age group of 31 to 40 years and mean age of 40.98 ± 10.13 years. Females and males were 68.0 and 32.0%, respectively. Among DOTS provider, 66.0% had served for more than 5 years of service and 84.0% of them had verified address before starting the treatment.

Conclusion

Majority of the DOTS provider had satisfactory knowledge and practice about PTB program. Proportion of the medical officers attending DOTS training was inadequate and there were adequate number of the health care workers who had attended DOTS training. There were no gaps found in proportion of the cases receiving the supervised treatment.
Does Evidence Matter? The Impact of Evidence Regarding Aid Effectiveness on Attitudes Towards Aid
Authors: Eger Jens , Schneider Sebastian H. , Bruder Martin , Gleser Solveig H.
Published: November 2022

Development aid is considered an important instrument in achieving a more sustainable global future. However, the general public perceives aid as rather ineffective. This may be because the public knows little about aid and its effects. Evidence for the effects of aid projects may therefore be of particular importance in shaping attitudes. In a survey experiment carried out among the German population (N ≈ 6000), we presented a claim on the effectiveness of an aid project or the same claim plus experimental evidence, qualitative evidence or anecdotal evidence and compared it to a no information control group. Results revealed that the claim increases both belief in the effectiveness of aid as well as support for aid. Among all forms of evidence tested, anecdotal evidence performs best, followed by experimental evidence. Pre-manipulation support for aid partly moderates the effect of the claim, but those who support aid do not react more strongly to the two forms of scientific evidence (experimental/qualitative).
Numerical study on the pulsating energy evolution in the cavitating flow around a mini Cascade
Authors: Yu An , Feng Wenjin , Tang Qinghong
Published: November 2022

Cavitation is arguably a highly turbulent phenomenon in the liquid flow system. The cavitating flow around a mini cascade was carried out to investigate the turbulent characteristics and pulsation mechanisms. The results demonstrate that cavitation can significantly affect the turbulence velocity fluctuation and turbulence anisotropy, and intensively alter the local turbulent energy. To better provide an understanding of fundamental mechanisms dictating time-averaged pulsating energy, the inhomogeneity of the local concentration of pulsating energy at the vapor–liquid interface and the turbulent vortex core involves different fundamental mechanisms are expounded thoroughly through the ability of the time-averaged turbulent kinetic energy and the time-averaged pulsating entropy. The pulsating energy of cavitating flow around the mini cascade is basically obtained from the time-averaged flow, while the surrounding dissipative mechanisms are driven by the diffusion and dissipation terms. Further, the new definition of viscous diffusion term is derived based on the resolved turbulent kinetic energy, which can also clearly delineate the diffusion effect of turbulent kinetic energy produced by the molecule viscosity. Finally, the turbulent kinetic energy and pulsating enstrophy transport mechanisms inside the shedding vortex are revealed as significant characteristics of the interaction between vortex dynamics and turbulence–cavitation.
A gas kinetic Lax–Wendroff scheme for low-speed isothermal rarefied gas flows
Authors: Li Weidong , Fang Ming , Zhao Jinshan , Tao Menglun , Mei Jie
Published: November 2022

Previously, a gas kinetic Bhatnagar–Gross–Krook (BGK) scheme was proposed by us for incompressible flows in the continuum limits. [W. Li and W. Li, “A gas-kinetic BGK scheme for the finite volume lattice Boltzmann method for nearly incompressible flows,” Comput. Fluids 162, 126–138 (2018).] In the present work, we extend the gas kinetic BGK scheme to simulate low-speed isothermal rarefied nonequilibrium gas flows. This scheme is a gas kinetic Lax–Wendroff scheme (GKLWS) for the discrete velocity Boltzmann equation in the finite volume discretization framework with second-order accuracy in both time and space. As collision and transport of the molecular particles are coupled in the present GKLWS, the time step of the present method is not limited by the relaxation time, for which the present scheme is efficient for multiscale gas flows. Moreover, the present GKLWS holds the asymptotic preserving (AP) property, which ensures that both the Navier–Stokes solutions in the continuum limits and free-molecular flow solutions in the rarefied limits can be reliably obtained. To validate the accuracy and AP property of the GKLWS, several numerical benchmarks of isothermal low-speed rarefied gas flows are simulated by the present scheme. The numerical results show that the present scheme can be a reliable multiscale method for all Knudsen number low-speed isothermal gas flows.
Prediction of submicron particle dynamics in fibrous filter using deep convolutional neural networks
Authors: Shirzadi Mohammadreza , Fukasawa Tomonori , Fukui Kunihiro , Ishigami Toru
Published: November 2022

This study developed a data-driven model for the prediction of fluid–particle dynamics by coupling a flow surrogate model based on the deep convolutional neural network (CNN) and a Lagrangian particle tracking model based on the discrete phase model. The applicability of the model for the prediction of the single-fiber filtration efficiency (SFFE) for elliptical- and trilobal-shaped fibers was investigated. The ground-truth training data for the CNN flow surrogate model were obtained from a validated computational fluid dynamics (CFD) model for laminar incompressible flow. Details of fluid–particle dynamics parameters, including fluid and particle velocity vectors and contribution of Brownian and hydrodynamic forces, were examined to qualitatively and quantitatively evaluate the developed data-driven model. The CNN model with the U-net architecture provided highly accurate per-pixel predictions of velocity vectors and static pressure around the fibers with a speedup of more than three orders of magnitude compared with CFD simulations. Although SFFE was accurately predicted by the data-driven model, the uncertainties in the velocity predictions by the CNN flow surrogate model in low-velocity regions near the fibers resulted in deviations in the particle dynamics predictions. These flow uncertainties contributed to the random motion of particles due to Brownian diffusion and increased the probability of particles being captured by the fiber. The findings provide guidelines for the development of data science-based models for multiphysics fluid mechanics problems encountered in fibrous systems.
Celebrating 60 years of
Authors: Singh Balwant , Tibbett Mark
Published: November 2022

An editorial to celebrate the 60th anniversary of the Soil Research journal.
Atmospheric turbulent structures and fire sweeps during shrub fires and implications for flaming zone behaviour
Authors: Katurji Marwan , Noonan Bob , Zhang Jiawei , Valencia Andres , Shumacher Benjamin , Kerr Jessica , Strand Tara , Pearce Grant , Zawar-Reza Peyman
Published: November 2022

Background Wildfires propagate through vegetation exhibiting complex spread patterns modulated by ambient atmospheric wind turbulence. Wind gusts at the fire-front extend and intensify flames causing direct convective heating towards unburnt fuels resulting in rapid acceleration of spread. Aims To characterise ambient and fire turbulence over gorse shrub and explore how this contributes to fire behaviour. Methods Six experimental burns were carried out in Rakaia, New Zealand under varying meteorological conditions. The ignition process ensured a fire-line propagating through dense gorse bush (1 m high). Two 30-m sonic anemometer towers measured turbulent wind velocity at six different levels above the ground. Visible imagery was captured by cameras mounted on uncrewed aerial vehicles at 200 m AGL. Key results Using wavelet decomposition, we identified different turbulent time scales that varied between 1 and 128 s relative to height above vegetation. Quadrant analysis identified statistical distributions of atmospheric sweeps (downbursts of turbulence towards vegetation) with sustained events emanating from above the vegetation canopy and impinging at the surface with time scales up to 10 s. Conclusions Image velocimetry enabled tracking of ‘fire sweeps’ and characterised for the first time their lifetime and dynamics in comparison with overlying atmospheric turbulent structures. Implications This methodology can provide a comprehensive toolkit when investigating coupled atmosphere–fire interactions.
A cost avoidance study of critical care pharmacists’ interventions in a tertiary institution in Singapore
Authors: Chan Lin En Jeremy , Soong Jie Lin , Lie Sui An
Published: November 2022

Purpose

The economic impact of critical care pharmacists in the intensive care unit (ICU) setting has not been evaluated in Singapore despite ICUs being high-cost areas. This study was conducted to determine the costs avoided as a result of pharmacists’ interventions within multidisciplinary ICU teams in a tertiary hospital in Singapore.

Methods

A single-center, retrospective observational study of accepted pharmacists’ interventions was conducted over 6 months in 2020. We adopted a previously published systematic approach to estimate the costs avoided by the healthcare system through pharmacists’ interventions. Interventions were independently reviewed by a critical care pharmacist, an intensivist, and an investigator. Cost avoidance was calculated in terms of the additional ICU length of stay that would have resulted had a pharmacist not intervened as well as the direct cost savings achieved.

Results

There were 632 medication-related problems (MRPs) associated with the 527 accepted interventions, as some interventions involved multiple MRPs. The most common interventions included correcting inappropriate drug regimens (n = 363; 57%), recommending drug monitoring (n = 65; 10%) and addressing omission of drugs (n = 50; 8%). Over 6 months, gross cost avoidance and net cost avoidance achieved were $186,852 and $140,004, respectively, resulting in a ratio of potential monetary cost avoidance to pharmacist salary of 3.99:1. The top 3 interventions that resulted in the greatest cost avoidance were those that corrected inappropriate drug regimens ($146,870; 79%), avoided adverse drug events (ADEs) ($10,048; 5%), and led to discontinuation of medications without any indication ($7,239; 4%).

Conclusion

Pharmacists can reduce healthcare expenditure substantially through cost avoidance by performing various interventions in ICUs, particularly in the areas of correcting inappropriate drug regimens, avoiding ADEs, and discontinuing unnecessary medications.
Procalcitonin for sepsis management: Implementation within an antimicrobial stewardship program
Authors: Fugit Randolph V , McCoury John B , Bessesen Mary T
Published: November 2022

Purpose

Clinical trials of procalcitonin (PCT)–based algorithms for antibacterial therapy have shown a reduction in antimicrobial use and improved survival. Translation of PCT algorithms to clinical settings has often been unsuccessful. We hypothesized that appropriate utilization of PCT could be improved by implementing an antimicrobial stewardship team (AST) approach to PCT testing.

Methods

We completed a pre-post intervention evaluation of adult patients admitted to the intensive care unit with a diagnosis of sepsis. The standard PCT algorithm period (SPAP) cohort included patients enrolled before dedicated AST involvement. During the AST-supported PCT algorithm period (ASPAP), the AST reviewed and provided feedback for all appropriate patients. The primary outcome was adherence to the PCT algorithm.

Results

Thirty-five and 57 patients were evaluated in the SPAP and ASPAP cohorts, respectively. There were no differences in demographics or infection site between the groups. Baseline PCT assessment was ordered in a larger proportion of patients in the ASPAP cohort (90% vs 57%; P = 0.0006). Follow-up PCT measurement was performed in more patients in the ASPAP cohort (76% vs 23%; P < 0.0001). Antibiotics were discontinued per algorithm in more patients in the ASPAP cohort (25/57 [44%] vs 2/35 [7%]; P < 0.0001). Patients in the ASPAP cohort experienced a shorter total duration of antibiotics (5 vs 7 days; P = 0.02), with no significant difference in length of stay or 30-day readmission or mortality between the cohorts.

Conclusion

A PCT algorithm successfully implemented by an AST was associated with a significant decrease in total antibiotic days with no differences in mortality or length of stay.
Description and financial impact of ambulatory care pharmacy team interventions within an underserved patient population
Authors: Hasham Salman , Moye-Dickerson Pamela , Thurston Maria Miller
Published: November 2022

Purpose

The purpose of this study was to characterize and quantify the types of interventions made by an ambulatory care pharmacy team (ACPT), evaluate the financial impact of such interventions, and create a cost template for the interventions using the health system’s intervention documentation system.

We conducted a retrospective, single-center cohort study covering the period from July 1, 2018, to June 30, 2020. Eligible participants included patients aged 18 years or older who had an appointment at the ambulatory care clinic and received a pharmacy consult. Most patients were uninsured. Data collected included intervention types, specific interventions, the economic impact per intervention, the average cost avoidance per intervention, the total economic impact, and the total cost avoidance. The ACPT documented a total of 1,334 interventions during the 2-year study period. The 4 major categories of interventions included patient counseling, drug utilization review, medication therapy management, and drug information. Each category was further subdivided into subcategories, for a total of 18 distinct subcategories. The economic impact per intervention was approximately $30. The average cost avoidance was estimated to be $357.62 per intervention, with a total economic impact of $40,020 and cost avoidance of $477,065 for the study period.

Conclusion

Pharmacist interventions resulted in a significant amount of economic impact and cost avoidance for the health system. Using the data from the study, we created a cost estimate to indicate the value of each ambulatory care intervention by using the health system’s intervention documentation system.
Mechanical scarification can reduce competitive traits of boreal ericaceous shrubs and improve nutritional site quality
Authors: Reicis Krista , Bradley Robert L , Joanisse Gilles , Thiffault Nelson , Scott Dalton , Parsons William F J
Published: November 2022

Ericaceous shrubs often interfere with the growth of black spruce seedlings on regenerating forest sites in Eastern Canada. Mechanical site preparation such as scarification may improve this situation, but it is uncertain whether this is solely due to a reduction in direct competition from the shrubs, or also from a sustained improvement in nutritional site quality. We sampled experimental plots in two boreal climate regions (i.e. warmer-drier Abitibi vs. cooler-wetter Côte-Nord) where scarification, performed 18 years earlier, had increased the growth of black spruce relative to non-scarified plots. Trees of scarified plots had closed the canopy more than trees of non-scarified plots in Côte-Nord, but not in Abitibi. Total ground cover of ericaceous shrubs was lower in scarified plots at both sites, the main species being Kalmia angustifolia (i.e. Kalmia) in Abitibi and Rhododendron groenlandicum (i.e. Labrador tea) in Côte-Nord. Scarified plots at both sites had significantly shorter current-year ericaceous rhizomes than non-scarified plots, but the difference between treatments was significantly greater in Côte-Nord than in Abitibi. In Côte-Nord, ericaceous shrubs on scarified plots had a lower specific rhizome mass, higher specific leaf area, lower tannin and higher N concentrations in leaves and litter, and lower N use efficiency than on non-scarified plots. By comparison, scarification in Abitibi affected only one foliar property, namely a reduction in the C:N ratio of Kalmia leaf litter. Forest floor N mineralization rates and black spruce needle N concentrations were higher in scarified than non-scarified plots across both sites. Taken collectively, results suggest that mechanical scarification on ericaceous shrub-dominated cutovers can reduce competitive traits of boreal ericaceous shrubs and improve nutritional site quality, especially in cooler-wetter climates.

Highlights
A qualitative evaluation of priority-setting by the Health Benefits Package Advisory Panel in Kenya
Authors: Mbau Rahab , Oliver Kathryn , Vassall Anna , Gilson Lucy , Barasa Edwine
Published: November 2022

Kenya’s Ministry of Health established the Health Benefits Package Advisory Panel (HBPAP) in 2018 to develop a benefits package for universal health coverage. This study evaluated HBPAP’s process for developing the benefits package against the normative procedural (acceptable way of doing things) and outcome (acceptable consequences) conditions of an ideal healthcare priority-setting process as outlined in the study’s conceptual framework. We conducted a qualitative case study using in-depth interviews with national-level respondents (n = 20) and document reviews. Data were analysed using a thematic approach. HBPAP’s process partially fulfilled the procedural and outcome conditions of the study’s evaluative framework. Concerning the procedural conditions, transparency and publicity were partially met and were limited by the lack of publication of HBPAP’s report. While HBPAP used explicit and evidence-based priority-setting criteria, challenges included lack of primary data and local cost-effectiveness threshold, weak health information systems, short timelines and political interference. While a wide range of stakeholders were engaged, this was limited by short timelines and inadequate financial resources. Empowerment of non-HBPAP members was limited by their inadequate technical knowledge and experience in priority-setting. Finally, appeals and revisions were limited by short timelines and lack of implementation of the proposed benefits package. Concerning the outcome conditions, stakeholder understanding was limited by the technical nature of the process and short timelines, while stakeholder acceptance and satisfaction were limited by lack of transparency. HBPAP’s benefits package was not implemented due to stakeholder interests and opposition. Priority-setting processes for benefits package development in Kenya could be improved by publicizing the outcome of the process, allocating adequate time and financial resources, strengthening health information systems, generating local evidence and enhancing stakeholder awareness and engagement to increase their empowerment, understanding and acceptance of the process. Managing politics and stakeholder interests is key in enhancing the success of priority-setting processes.
Low-carbon supply chain operations: impacts of carbon tax and fairness concerns
Authors: Shi Song
Published: November 2022

Under a carbon tax, this study established game theory models of a low-carbon supply chain to investigate the effects of fairness and carbon tax rate on the retail price and on carbon emission reduction level, as well as on the profits of the manufacturer, retailer and the whole supply chain. Results show that the carbon emission reduction level and the supply chain profit under a centralized supply chain are both higher than those under a decentralized supply chain, if the manufacturer’s fairness concern, the carbon emission reduction level and the supply chain profit will further decrease, but manufacturers’ profits are taking a growing share of the supply chain’s total profits. Under three different modes, the carbon emission reduction level will increase with the increase of the carbon coefficient. The retail price and the supply chain profit are jointly determined by the carbon tax rate and the carbon coefficient. Moreover, the implementation of a carbon reduction investment cost-sharing contract can increase the demand of low-carbon products and reduce the retail price. Under a carbon tax, regardless of whether manufacturers pay attention to fairness, the carbon reduction investment cost-sharing contract can effectively improve the overall efficiency of the low-carbon supply chain.
A learning scheme by sparse grids and Picard approximations for semilinear parabolic PDEs
Authors: Chassagneux Jean-François , Chen Junchao , Frikha Noufel , Zhou Chao
Published: November 2022

Relying on the classical connection between backward stochastic differential equations and nonlinear parabolic partial differential equations (PDEs), we propose a new probabilistic learning scheme for solving high-dimensional semilinear parabolic PDEs. This scheme is inspired by the approach coming from machine learning and developed using deep neural networks in Han et al. (2018, Solving high-dimensional partial differential equations using deep learning. Proc. Natl. Acad. Sci., 115, 8505–8510. Our algorithm is based on a Picard iteration scheme in which a sequence of linear-quadratic optimization problem is solved by means of stochastic gradient descent algorithm. In the framework of a linear specification of the approximation space, we manage to prove a convergence result for our scheme, under some smallness condition. In practice, in order to be able to treat high-dimensional examples, we employ sparse-grid approximation spaces. In the case of periodic coefficients and using pre-wavelet basis functions, we obtain an upper bound on the global complexity of our method. It shows, in particular, that the curse of dimensionality is tamed in the sense that in order to achieve a root mean squared error of order $\varepsilon $, for a prescribed precision $\varepsilon $, the complexity of the Picard algorithm grows polynomially in $\varepsilon ^{-1}$ up to some logarithmic factor $|\!\log (\varepsilon )|$, whose exponent grows linearly with respect to the PDE dimension. Various numerical results are presented to validate the performance of our method, and to compare them with some recent machine learning schemes proposed in E et al. (2017, Deep learning-based numerical methods for high-dimensional parabolic partial differential equations and backward stochastic differential equations. Commun. Math. Stat., 5, 349–380) and Huré et al. (2020, Deep backward schemes for high-dimensional nonlinear PDEs. Math. Comput., 89, 1547–1579).
Nonlinear model fitting analysis of feather growth and development curves in the embryonic stages of Jilin white geese (Anser cygnoides)
Authors: Wang Yudong , Fu Xianou , Wang Sihui , Mabrouk Ichraf , Zhou Yuxuan , Song Yupu , Liu Tuoya , Ma Jingyun , Zhuang Fangming , Zhang Xue , Xu Keyi , Sun Yongfeng
Published: November 2022

Poultry is subject to varying degrees of feather loss and feather pecking during production, which seriously affects the live appearance and carcass appearance of their commercial traits and greatly reduces the production profitability of the farming enterprise. It also has an impact on down production and quality in the case of geese. In this study, mathematical models (Logistic, Gompertz, and Von Bertalanffy) were used to assess feather growth and development during the embryonic period in Jilin white geese (Anser cygnoides) predicting the weight and length of feathers from the back, chest, and belly tracts at different embryonic ages, to determine which growth model more accurately described feather growth patterns. The result first showed that the primary feather follicles of the Jilin white goose developed at E14 and secondary feather follicles at E18; primary feather follicle density increased and then decreased, whereas secondary feather follicle density increased continuously and the primary and secondary feather follicles developed independently. Secondly, the embryonic feather growth followed a slow–fast–slow pattern, with feathers growing slowly from E12 to E18, quickly from E18 to E24, and then decreasing after E24 until just before emergence (E30). In addition, before E14, feathers were concentrated in the back tracts, and no feathers were found on the head, neck, chest, abdomen, or wings. By E22, the whole body of the embryo was covered with feathers, and the back feathers were the earliest and fastest to develop. Compared to the Gompertz and von Bertalanffy models, the logistic model fit (R2 = 0.997) was the highest, while the sum of residual squares (RSS = 25661.67), Akaike’s information criterion (AIC = 77.600), Bayesian information criterion (BIC = 78.191), and mean square error (MSE = 2851.296) were the lowest. Therefore, the logistic model was more suitable for describing the changes in whole-body feather growth during the embryonic period in Jilin white geese. In conclusion, using the growth curve model to explain the relationship between feather growth and embryonic age in geese will potentially speed up the process of genetic improvement in Jilin white geese (A. cygnoides) and thus provide scientific support for molecular genetic breeding.
An In silico study of derivative of Newcastle disease virus epitopes based vaccine against Hemagglutunin neuraminidase protein
Authors: Jamil Farrukh , Aslam Laiba , Laraib  , Ali Hira , Shoukat Kainaat , Rasheed Muhammad Asif , Raza Sohail , Ibrahim Muhammad
Published: November 2022

The causative agent of Newcastle disease (ND) is Newcastle disease virus. It belongs to avian species of Orthoavulavirus, Avulavirinae subfamily and if left untreated it may cause epidemic in poultry. Many vaccines have been made against Newcastle disease based on inactivated and attenuated viruses but become useless due to the genetic changes in the virus. We have recently reported epitope based vaccine by using immunoinformatics approaches. The vaccine was previously constructed against Hemagglutunin neuraminidase protein of Newcastle disease virus. Here we extended our work to develop several chimera of the proposed vaccine to design a new multi-epitope vaccine by shuffling the cytotoxic T lymphocytes (CTL) segments of the vaccine. Total 5040 constructs have been analyzed by shuffling 7 CTL epitopes. Highest antigenic multi-epitope construct was selected for the further study. Our new multi-epitope vaccine (MEV) construct contains 259 amino acids and is immunogenic, more antigenic and non-allergen. The refinement of the structure of MEV construct was performed. Molecular docking analyses showed its maximum binding with avian Toll-like 4 receptor. Subsequently, immune simulations showed its predicted ability to induce the host primary and secondary responses. Study suggests that our new multi-epitope vaccine chimera is more effective and stable protein against Newcastle disease virus strains in Pakistan. However, further studies are required to validate the vaccine through In vitro and In vivo studies.
Tolerance levels of mass density for adaptive helical tomotherapy using MVCT
Authors: Tsunemine Shogo , Ozawa Shuichi , Nakao Minoru , Miura Hideharu , Saito Akito , Kawahara Daisuke , Onishi Yasuhiko , Onishi Takashi , Okawa Fumito , Terai Atsushi , Hashiguchi Taiki , Yamasaki Hidetoshi , Maruta Tsutomu , Murakami Yuji , Nagata Yasushi
Published: November 2022

Daily dose distributions for adaptive radiotherapy (ART) using helical tomotherapy (HT) are calculated using megavoltage computed tomography (MVCT). Generally, the MVCT number is converted to mass density (MD) using an MD calibration table (MVCT-MD table). The aims of this study are to calculate the tolerance levels of the MD for ART and to evaluate the tolerance levels using clinical patient plans. These tolerance levels of MD were calculated based on the tissue maximum ratio (TMR) of 6MV flattening-filter-free (FFF) beam of HT and the effective tissue thickness data from an International Commission on Radiological Protection 110 phantom data for lung, adipose/muscle and cartilage/spongy-bone. These tolerance levels were determined by considering both the MD causing a dose error of 2% and the variation in MVCT numbers. Subsequently, the stability of the MD values was estimated with the standard deviations (SD) in the MVCT number over 6 months. The dose distribution for clinical patient plans was calculated using the MVCT-MD table with added tolerance levels. These tolerance levels were determined as MD differences causing a dose error of 2%, and were ± 0.049 g/cm3, ± 0.030 g/cm3 and ± 0.049 g/cm3 for lung, adipose/muscle and cartilage/spongy-bone, respectively. The calculated dose distribution errors using the MVCT-MD table added tolerance levels were within 2%. We proposed these tolerance levels in MD for the quality control of the MVCT-MD table.
Correlation between the expression of LAT1 in cancer cells and the potential efficacy of boron neutron capture therapy
Authors: Watanabe Tsubasa , Sanada Yu , Hattori Yoshihide , Suzuki Minoru
Published: November 2022

Boron neutron capture therapy (BNCT) is a binary cancer therapy that involves boron administration and neutron irradiation. The nuclear reaction caused by the interaction of boron atom and neutron produces heavy particles with highly cytocidal effects and destruct tumor cells, which uptake the boron drug. p-Boronophenylalanine (BPA), an amino acid derivative, is used in BNCT. Tumor cells with increased nutrient requirements take up more BPA than normal tissues via the enhanced expression of LAT1, an amino acid transporter. The current study aimed to assess the correlation between the expression of LAT1 and the uptake capacity of BPA using genetically modified LAT1-deficient/enhanced cell lines. We conducted an in vitro study, SCC7 tumor cells wherein LAT1 expression was altered using CRISPR/Cas9 were used to assess BPA uptake capacity. Data from The Cancer Genome Atlas (TCGA) were used to examine the expression status of LAT1 in human tumor tissues, the potential impact of LAT1 expression on cancer prognosis and the potential cancer indications for BPA-based BNCT. We discovered that the strength of LAT1 expression strongly affected the BPA uptake ability of tumor cells. Among the histologic types, squamous cell carcinomas express high levels of LAT1 regardless of the primary tumor site. The higher LAT1 expression in tumors was associated with a higher expression of cell proliferation markers and poorer patient prognosis. Considering that BPA concentrate more in tumors with high LAT1 expression, the results suggest that BNCT is effective for cancers having poor prognosis with higher proliferative potential and nutritional requirements.
Hydraulic integrity of plant organs during drought stress and recovery in herbaceous and woody plant species
Authors: Huber Annika E , Melcher Peter J , Bauerle Taryn L
Published: November 2022

The relationship between root, stem, and leaf hydraulic status and stomatal conductance during drought (field capacities: 100–25%) and drought recovery was studied in Helianthus annuus and five tree species (Populus×canadensis, Acer saccharum, A. saccharinum, Picea glauca, and Tsuga canadensis). Measurements of stomatal conductance (gs), organ water potential, and vessel embolism were performed and the following was observed: (i) cavitation only occurred in the petioles and not the roots or stems of tree species regardless of drought stress; (ii) in contrast, all H. annuus organs exhibited cavitation to an increasing degree from root to petiole; and (iii) all species initiated stomatal closure before cavitation events occurred or the expected turgor loss point was reached. After rewatering: (i) cavitated vessels in petioles of Acer species recovered whereas those of P. ×canadensis did not and leaves were shed; (ii) in H. annuus, cavitated xylem vessels were refilled in roots and petioles, but not in stems; and (iii) despite refilled embolisms in petioles of some species during drought recovery, gs never returned to pre-drought conditions. Conclusions are drawn with respect to the hydraulic segmentation hypothesis for above- and below-ground organs, and the timeline of embolism occurrence and repair is discussed.
Chemical evolution of elliptical galaxies I: supernovae and AGN feedback
Authors: Molero Marta , Matteucci Francesca , Ciotti Luca
Published: November 2022

We study the formation and evolution of elliptical galaxies and how they suppress star formation and maintain it quenched. A one-zone chemical model which follows in detail the time evolution of gas mass and its chemical abundances during the active and passive evolution is adopted. The model includes both gas infall and outflow as well as detailed stellar nucleosynthesis. Elliptical galaxies with different infall masses, following a down-sizing in star formation scenario, are considered. In the chemical evolution simulation, we include a novel calculation of the feedback processes. We include heating by stellar wind, core-collapse supernovae (SNe), Type Ia SNe (usually not highlighted in galaxy formation simulations), and active galactic nucleus (AGN) feedback. The AGN feedback is a novelty in this kind of models and is computed by considering a Bondi-Eddington limited accretion onto the central supermassive black hole. We successfully reproduce several observational features, such as the [α/Fe] ratios increasing with galaxy mass, mass-metallicity, MBH–σ and MBH–M* relations. Moreover, we show that stellar feedback and in particular Type Ia SNe, has a main role in maintaining quenched the star formation after the occurrence of the main galactic wind, especially in low-mass ellipticals. For larger systems, the contribution from AGN to thermal energy of gas appears to be necessary. However, the effect of the AGN on the development of the main galactic wind is negligible, unless an unreasonable high-AGN efficiency or an extremely low-stellar feedback are assumed. We emphasize the important role played by Type Ia SNe in the energy budget of early-type galaxies.
Invoking the virial theorem to understand the impact of (dry) mergers on the Mbh–σ relation
Authors: Graham Alister W
Published: November 2022

While dry mergers can produce considerable scatter in the (black hole mass, Mbh)-(spheroid stellar mass, M*, sph) and Mbh-(spheroid half-light radius, Re, sph) diagrams, the virial theorem is used here to explain why the scatter about the Mbh–(velocity dispersion, σ) relation remains low in the face of such mergers. Its small scatter has been claimed as evidence of feedback from active galactic nuclei (AGNs). However, it is shown that galaxy mergers also play a significant role. The collision of two lenticular (S0) galaxies is expected to yield three types of merger product (a core-Sérsic S0, an ellicular ES,e or an elliptical E galaxy), depending on the remnant’s orbital angular momentum. It is shown that the major merger of two S0 galaxies with M*, sph ∼ 1011 M⊙ advances the system along a slope of ∼5 in the Mbh-σ diagram, while a major E+E galaxy merger moves a system slightly along a trajectory with a slope of ∼9. Mergers of lower-mass S0 galaxies with M*, sph ∼ 1010 M⊙ move slightly along a trajectory with a slope of ∼3, thereby further contributing to the steeper distribution for the E (and Es,e) galaxies in the Mbh-σ diagram, reported here to have a slope of 7.27 ± 0.91, compared to the S0 galaxies that have a slope of 5.68 ± 0.60. This result forms an important complement to the AGN feedback models like that from Silk & Rees, providing a more complete picture of galaxy/(black hole) co-evolution. It also has important implications for nanohertz gravitational-wave research.
Globular cluster ultraluminous X-ray sources in the furthest early-type galaxies
Authors: Thygesen Erica , Sun Yifan , Huang Jeff , Dage Kristen C , Zepf Stephen E , Kundu Arunav , Haggard Daryl , Maccarone Thomas J
Published: November 2022

Ultraluminous X-ray sources (ULXs) in globular clusters (GCs) are low-mass X-ray binaries that achieve high X-ray luminosities through a currently uncertain accretion mechanism. Using archival Chandra and Hubble Space Telescope observations, we perform a volume-limited search (≲70 Mpc) of 21 of the most massive ($\gt 10^{11.5} \, \mathrm{M}_\odot$) early-type galaxies to identify ULXs hosted by GC candidates. We find a total of 34 ULX candidates above the expected background within five times the effective radius of each galaxy, with 10 of these ($\sim 29.4{{\ \rm per\ cent}}$) potentially hosted by a GC. A comparison of the spatial and luminosity distributions of these new candidate GC ULXs with previously identified GC ULXs shows that they are similar: both samples peak at LX ∼ a few × 1039 erg s−1 and are typically located within a few effective radii of their host galaxies.
High-resolution resonant portraits of a single-planet white dwarf system
Authors: Veras Dimitri , Georgakarakos Nikolaos , Dobbs-Dixon Ian
Published: November 2022

The dynamical excitation of asteroids due to mean motion resonant interactions with planets is enhanced when their parent star leaves the main sequence. However, numerical investigation of resonant outcomes within post-main-sequence simulations is computationally expensive, limiting the extent to which detailed resonant analyses have been performed. Here, we combine the use of a high-performance computer cluster and the general semi-analytical libration width formulation of Gallardo, Beaugé & Giuppone in order to quantify resonant stability, strength, and variation instigated by stellar evolution for a single-planet system containing asteroids on both crossing and non-crossing orbits. We find that resonant instability can be accurately bound with only main-sequence values by computing a maximum libration width as a function of asteroid longitude of pericentre. We also quantify the relative efficiency of mean motion resonances of different orders to stabilize versus destabilize asteroid orbits during both the giant branch and white dwarf phases. The 4:1, 3:1, and 2:1 resonances represent efficient polluters of white dwarfs, and even when in the orbit-crossing regime, both the 4:3 and 3:2 resonances can retain small reservoirs of asteroids in stable orbits throughout giant branch and white dwarf evolution. This investigation represents a preliminary step in characterizing how simplified extrasolar Kirkwood gap structures evolve beyond the main sequence.
Multifilter observations of the complex periodic variations in eight pre-main sequence stars
Authors: Koen Chris
Published: November 2022

Follow up time series photometry through various combinations of the BVRCIC filter set is presented for eight young stars. The complex periodic variability of seven of the stars was first discovered in TESS photometry, while one star was first observed by K2. The periods of the stars are short – 0.2–0.4 d. Reddening, effective temperatures, and bolometric magnitudes are estimated by fitting spectral energy distributions. The new photometry typically covers several cycles of variability. In some cases, photometry was obtained in more than one observing season. All new light curves differ from those obtained from satellite missions, in some cases substantially so. Amplitudes are almost always larger, the shorter the effective wavelength of the filter, but the relationship can be weak or non-monotonic. Given that all but one of the stars are in associations older than 10 Myr, it seems unlikely that protoplanetary discs play an important role in the complex variability patterns. Modelling of the wavelength dependence of amplitudes in terms of dust absorption in debris discs is explored. The conclusion is that excesses of small grains as compared with the average Galactic composition would be required.
Advective accretion disc-corona model with fallback for tidal disruption events
Authors: Mageshwaran T , Bhattacharyya Sudip
Published: November 2022

Tidal disruption events (TDEs) show a correlation between the UV to X-ray spectral index and the Eddington ratio, with non-thermal X-ray emission at the low Eddington ratio. We consider the corona surrounding the accretion disc as a non-thermal X-ray source. We construct a time-dependent and non-relativistic advective accretion disc-corona model for TDEs. The infalling debris is assumed to form a seed disc in time tc, that evolves due to the mass gain from the infalling debris at the constant outer radius with a mass fallback rate $\dot{M}_{\rm fb}$ and the mass loss through accretion onto the black hole. The viscous stress in our model depends on gas (Pg) and total (Pt) pressures as $\tau _{r\phi } \propto P_\mathrm{g}^{1-\mu } P_\mathrm{t}^{\mu }$, where μ is a constant. We find that the mass accretion rate $\dot{M}_a$ evolves from Eddington to sub-Eddington accretion with a late-time evolution close to t−5/3, where t is the time. We find that the bolometric disc luminosity follows a late-time evolution close to t−5/3. The ratio of total X-ray luminosity from corona to bolometric disc luminosity increases with μ and increases at late times for μ ≠ 1. We obtain the X-ray blackbody temperature of the disc that agrees with the temperature from X-ray observations (∼ 105 K). We find the radiative efficiency of the disc increases with time and decreases for a disc when the corona is included. We have neglected the outflow, and our model is more applicable for near-to-sub-Eddington accretion and when $\dot{M}_{\rm fb}$ is sub-Eddington.
BASS XXXIX: Swift-BAT AGN with changing-look optical spectra
Authors: Temple Matthew J , Ricci Claudio , Koss Michael J , Trakhtenbrot Benny , Bauer Franz E , Mushotzky Richard , Rojas Alejandra F , Caglar Turgay , Harrison Fiona , Oh Kyuseok , Padilla Gonzalez Estefania , Powell Meredith C , Ricci Federica , Riffel Rogério , Stern Daniel , Urry C Megan
Published: November 2022

Changing-look (CL) AGN are unique probes of accretion onto supermassive black holes (SMBHs), especially when simultaneous observations in complementary wavebands allow investigations into the properties of their accretion flows. We present the results of a search for CL behaviour in 412 Swift-BAT detected AGN with multiple epochs of optical spectroscopy from the BAT AGN Spectroscopic Survey (BASS). 125 of these AGN also have 14–195  keV ultra-hard X-ray light curves from Swift-BAT which are contemporaneous with the epochs of optical spectroscopy. Eight CL events are presented for the first time, where the appearance or disappearance of broad Balmer line emission leads to a change in the observed Seyfert type classification. Combining with known events from the literature, 21 AGN from BASS are now known to display CL behaviour. Nine CL events have 14–195  keV data available, and five of these CL events can be associated with significant changes in their 14–195  keV flux from BAT. The ultra-hard X-ray flux is less affected by obscuration and so these changes in the 14–195 keV band suggest that the majority of our CL events are not due to changes in line-of-sight obscuration. We derive a CL rate of 0.7–6.2 per cent on 10–25 yr time-scales, and show that many transitions happen within at most a few years. Our results motivate further multiwavelength observations with higher cadence to better understand the variability physics of accretion onto SMBHs.
An accurate treatment of scattering and diffusion in piecewise power-law models for cosmic ray and radiation/neutrino transport
Authors: Hopkins Philip F
Published: November 2022

A popular numerical method to model the dynamics of a ‘full spectrum’ of cosmic rays (CRs), also applicable to radiation/neutrino hydrodynamics, is to discretize the spectrum at each location/cell as a piecewise power law in ‘bins’ of momentum (or frequency) space. This gives rise to a pair of conserved quantities (e.g. CR number and energy) that are exchanged between cells or bins, which in turn give the update to the normalization and slope of the spectrum in each bin. While these methods can be evolved exactly in momentum-space (e.g. considering injection, absorption, continuous losses/gains), numerical challenges arise dealing with spatial fluxes, if the scattering rates depend on momentum. This has often been treated either by neglecting variation of those rates ‘within the bin,’ or sacrificing conservation – introducing significant errors. Here, we derive a rigorous treatment of these terms, and show that the variation within the bin can be accounted for accurately with a simple set of scalar correction coefficients that can be written entirely in terms of other, explicitly evolved ‘bin-integrated’ quantities. This eliminates the relevant errors without added computational cost, has no effect on the numerical stability of the method, and retains manifest conservation. We derive correction terms both for methods that explicitly integrate flux variables (e.g. two-moment or M1-like) methods, as well as single-moment (advection-diffusion, FLD-like) methods, and approximate corrections valid in various limits.
Chandra measurements of gas homogeneity and turbulence at intermediate radii in the Perseus Cluster
Authors: de Vries Martijn , Mantz Adam B , Allen Steven W , Morris R Glenn , Zhuravleva Irina , Canning Rebecca E A , Ehlert Steven R , Ogorzałek Anna , Simionescu Aurora , Werner Norbert
Published: November 2022

We present a Chandra study of surface brightness fluctuations in the diffuse intracluster medium of the Perseus Cluster. Our study utilizes deep, archival imaging of the cluster core as well as a new mosaic of 29 short $\, 5\,$-ks observations extending in eight different directions out to radii of $r_{500} \sim 2.2\, r_{2500}$. Under the assumption that the distribution of densities at a given radius is log-normally distributed, two important quantities can be derived from the width of the log-normal density distribution on a given spatial scale: the density bias, that is equal to the square root of the clumping factor C; and the one-component turbulent velocity, vk,1D. We forward-model all contributions to the measured surface brightness, including astrophysical and particle background components, and account for the Poisson nature of the measured signal. Measuring the distribution of surface brightness fluctuations in 1 arcmin2 regions, spanning the radial range $0.3\rm {-}2.2\, r_{2500}$ ($7.8\rm {-}57.3\,$ arcmin), we find a small to moderate average density bias of around $3{{\ \rm per\ cent}}$ at radii below $1.6\, r_{2500}$. We also infer an average turbulent velocity at these radii of V1D < 400 km s−1. Direct confirmation of our results on turbulent velocities inferred from surface brightness fluctuations should be possible using the X-ray calorimeter spectrometers to be flown aboard the XRISM and Athena observatories.