bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessing the patterns and drivers of shape complexity in the amblypygid pedipalp
Authors: McLean Callum , Garwood Russell , Brassey Charlotte
Published: July 2021

Amblypygi is an arachnid order possessing a unique pair of spined pedipalps: appendages that perform in prey capture, courtship, and contest. Pedipalp length, hypothesized to be under sexual selection, varies markedly across amblypygid species, and pedipalp spination, thought to reflect selection for function in prey capture, also differs interspecifically. Differences in pedipalp shape between species may indicate that the relative strength of selection for prey capture and sexual selection vary across the group. However, interspecific differences in pedipalp shape have not been quantified, due to difficulties in identifying homologous features. For the first time, we quantify trends in amblypygid pedipalp shape complexity. We use elliptical Fourier analysis to quantify 2D complexity in pedipalp outlines across eleven species and six genera. We find that complexity significantly decreases as pedipalp length increases. This appears to be driven by relative spine length, suggesting that a trade‐off exists between pedipalp length and spination. Furthermore, significant female‐biased sexual dimorphism in shape complexity is present in the tibial segment of the amblypygid pedipalp. Our results provide novel insights into the drivers of amblypygid pedipalp evolution and suggest that a functional trade‐off between performance in prey capture and other functions under sexual selection exist in this enigmatic structure.
Mapping the premigration distribution of eastern Monarch butterflies using community science data
Authors: Momeni‐Dehaghi Iman , Bennett Joseph R. , Mitchell Greg W. , Rytwinski Trina , Fahrig Lenore
Published: July 2021

Knowing the distribution of migratory species at different stages of their life cycle is necessary for their effective conservation. For the Monarch butterfly (Danaus plexippus), although its overwintering distribution is well known, the available information on premigration distribution is limited to the studies estimating the natal origins of overwintering Monarchs in Mexico (i.e., postmigration data). However, the premigration distribution and the natal origins of overwintering Monarchs can be equivalent only if we assume that migrating Monarchs have the same mortality rate irrespective of their origins. To estimate Monarchs’ premigration distribution, we used data reported by community scientists before Monarchs start their fall migration, that is, before migration mortality, and controlled for sampling bias. Our premigration distribution map indicated that Minnesota, Texas, and Ontario are the states/provinces with the highest abundance of Monarch in North America. Although this higher estimated abundance can be related to the large sizes of these states/provinces, this information is still important because it identifies the management jurisdictions with the largest responsibility for the conservation of the premigration population of Monarchs. Our premigration distribution map will be useful in future studies estimating the rates, distribution, and causes of mortality in migrating Monarchs.
An efficient and simplified Gay‐Lussac approach in secondary variables form for the non‐Boussinesq simulation of free convection problems
Authors: Mayeli Peyman , Sheard Gregory J.
Published: July 2021

The Gay‐Lussac (GL) approach is an incompressible‐based strategy for non‐Boussinesq treatment of the governing equations for free convection problems that is established based on extending the density variations beyond the gravity term. Such a strategy leads to emerging the GL parameter as a non‐Boussinesq prefactor of different terms in the governing equations. In this article, the GL approach is expressed/discussed in terms of the secondary variables, that is, vorticity and stream‐function, for the first time and a simplified version of this approach is proposed by removing density variations from the continuity equation. The difference of results under the simplified and traditional GL approach ranges within a maximum of 1% for different parameters. The lower computational cost of numerical solution of governing equations in the secondary variables formula and the corresponding convergence rate is scrutinized for the simplified GL approach showing around 25% lower computational cost. The performance of this approach is evaluated at high relative temperature differences against the low Mach number scheme and the Boussinesq approximations. In this respect, natural convection in an annulus cavity is numerically simulated using a CVFEM solver under the aforementioned approximations up to Rayleigh number at Prandtl number and high relative temperature differences ( and 0.3). The largest deviations found for either the simplified GL or Boussinesq methods from the low Mach number scheme solution are less than 20% for velocity magnitude, 14% for stream function, 6% for vorticity, and 5% for temperature. Results under the three approximations are also analyzed in terms of the skin friction and local and average Nusselt number, indicating that the Gay‐Lussac approach requires some revisions to act more accurately than the classical Boussinesq approximation at high relative temperature differences in natural convection problems, especially within the convection dominated regime.
Betaine, a component of Lycium chinense, enhances muscular endurance of mice and myogenesis of myoblasts
Authors: Lee Sang‐Soo , Kim Yong‐An , Eun Bokkee , Yoo Jayeon , Kim Eun‐Mi , Nam Myoung Soo , Kim Kee K.
Published: July 2021

Sarcopenia is a disease characterized by the loss of muscle mass and function that occurs mainly in older adults. The present study was designed to investigate the hypothesis that water extract of Lycium chinense (WELC) would improve muscle function and promote myogenesis for sarcopenia. We investigated the effect of water extracts of L. chinense on muscular endurance function and myogenesis to examine its efficacy in sarcopenia. Intake of WELC‐containing cheese enhanced the muscular endurance function of mice in treadmill endurance tests. In addition, the cross‐sectional areas of muscle fibers in the gastrocnemius muscle of L. chinense‐fed mice were greater than that of control mice. Furthermore, WELC and its key component marker substance betaine promoted myogenesis of myoblasts by increasing the expression of the myogenic protein myosin heavy chain 3 (Myh3) and myotube formation. Taken together, our results suggest that L. chinense may potentially be useful in the development of preventive and therapeutic agents for sarcopenia, as well as in providing basic knowledge on myogenesis and muscular functions.
Return and volatility connectedness of Chinese onshore, offshore, and forward exchange rate
Authors: Zhao Yanping , Umar Zaghum , Vo Xuan Vinh
Published: July 2021

We analyze the return and volatility connectedness between the three Chinese exchange rate markets, namely, the onshore market, the offshore market, and the nondeliverable forward offshore market. Our results show that connectedness exhibits an increasing trend with fluctuations during periods of internal reforms and external shocks. For example, the connectedness increased with China's exchange rate reform on August 11, 2015 but dropped after that. Furthermore, we document that the offshore spot and a forward market dominated the other rates in return spillovers. In contrast, both the offshore and onshore forward rates dominated the other rates in volatility spillovers.
Feasibility of endoscopic evaluation of Helicobacter pylori infection status by using the Kyoto classification of gastritis in the population‐based gastric cancer screening program: A prospective cohort study
Authors: Hirai Ryosuke , Hirai Mami , Shimodate Yuichi , Minami Mariko , Ishikawa Sho , Kanadani Takafumi , Takezawa Rio , Doi Akira , Nishimura Naoyuki , Mouri Hirokazu , Matsueda Kazuhiro , Yamamoto Hiroshi , Mizuno Motowo
Published: July 2021

Background and aims

We have started a new population‐based endoscopic gastric cancer screening program in Kurashiki city with consideration of Helicobacter pylori infection status based on endoscopic features. We aimed to verify the feasibility of this attempt in a prospective case‐registration study (UMIN000028629).

Methods

Data were collected from 1784 subjects without past eradication of H. pylori and who underwent endoscopic gastric cancer screening in Kurashiki Central Hospital Preventive Healthcare Plaza from September 2017 to June 2018. Endoscopic judgment of H. pylori infection status was made according to the Kyoto classification of gastritis. For comparison, a combination serum test of anti‐H. pylori antibody and pepsinogen I and II, the ABC method, was used.

Results

The endoscopic diagnoses were nongastritis, 1215 (68.1%); active or inactive gastritis, 469 (26.3%); and undefined, 23 (1.3%). With the ABC method as a reference standard, the false‐negative rate of the endoscopic judgment for H. pylori infection was 16.3% (95% confidence interval: 13.1%‐20.0%). Most false‐negative cases were of Group B in the ABC method, which is considered gastritis with mild mucosal atrophy. Antibody titers in this population were mostly in the weak‐positive range but clinically significant elevation of the antibody suggesting current infection was observed in some cases.

Conclusions

Endoscopic diagnosis of H. pylori infection status in a population‐based gastric cancer screening program is mostly reliable, but false‐negative results may occur, especially in patients with mild gastric atrophy. To avoid this limitation, we recommend adding H. pylori antibody test to the program.
A cross‐sectional study on evaluation of complete blood count‐associated parameters for the diagnosis of acute appendicitis
Authors: Maghsoudi Leila Haji , Kabir Kourosh , Soltanian Ali , Pak Haleh , Ahmadinejad Mojtaba , Ahmadi Arghavan Khas
Published: July 2021

Background and aims

Acute appendicitis is one of the common causes of abdominal surgeries, however, the rate of negative appendectomy is as high as 20% as the diagnosis of appendicitis is challenging. The study aimed to evaluate complete blood count (CBC)‐associated parameters among positive and negative appendectomy patients and determine their diagnostic importance.

Methods

In this cross‐sectional study, patients who suspected of acute appendicitis were included. Preoperative blood samples taken from these patients for a complete blood count. Following parameters evaluated from their CBC: white blood cell (WBC), platelet (PLT), mean platelet volume (MPV), neutrophils‐to‐lymphocytes ratio, platelets‐to‐lymphocytes ratio, red cell distribution width (RDW), and platelet distribution width (PDW). These parameters analyzed for the positive and negative appendectomy patients using statistical analysis.

Results

Of 200 patients included in the study, 30 patients (15%) underwent negative appendectomy. The mean neutrophils, WBC, red blood cells, neutrophils‐to‐lymphocytes, and platelets‐to‐lymphocytes ratio was significantly high among positive appendectomy patients, (P < .05), whereas MPV to platelet ratio was significantly less in this group. The highest diagnostic power for the diagnosis of appendicitis was of neutrophils‐to‐lymphocytes ratio with the sensitivity of 83.5% and the specificity of 90%.

Conclusion

The findings of our study indicate that neutrophils‐to‐lymphocytes ratio alone is not sufficient for preoperative diagnosis of acute appendicitis and other CBC‐related parameters did not have good sensitivity and specificity. Further studies are therefore required in this area.
Analysis on flow structure and improvement of heat transfer in 3D circular tube with varying axial groove turbulator configurations
Authors: Al‐Obaidi Ahmed Ramadhan , Alhamid Jassim , Saleh Qasim
Published: July 2021

Using passive devices are an efficient method to enhance streamline behavior when liquid flows through the circular pipe. The interrupted structure groove is usually used to change the flow patterns. In this analysis, a heat performance numerical technique is applied to study the characteristics of fluid flow and heat transfer of the circular pipe using different axial groove geometrical configurations with different axial groove numbers, including 2, 3, and 4, under different conditions. The number of annular grooves and circumferential positions are the important parameters to analyse with varying operating conditions, with the Reynolds number (Re) range from 1500 to 23,000. A three‐dimensional coordinate pipe system is applied using tetrahedron grids. The discretization equations are obtained by deriving algebraic approximations to integral conservation equations. Results observed that using this type of passive method has a low effect on pressure dope compared to the normal one (smooth pipe). The flow change occurs near and closed to the axial groove parameters. Moreover, the Nusselt number (Nu) value for the groove turbulators was higher than the normal one, about 14.5%–21%. The friction factor (f) value for the groove turbulators was higher than the normal one, were about 7.5%–24%. Most friction losses are caused by dynamical pressure dissipation owing to more viscous losses closed to the wall surfaces. The improvement of heat performance using this type of passing method was more than 1.2%.
Determining injection strategies of phosphorus‐coupled nitrogen fertigation based on clogging control of drip emitters with saline water application*
Authors: Wang Zhen , Li Jiusheng , Yang Xiaoqi
Published: July 2021

The beneficial effect of fertigation with acidic fertilizers to protect emitters from chemical and biological clogging might be inhibited by improper fertigation modes. An on‐site drip irrigation experiment was conducted to investigate the injection strategies of phosphorus (P)‐coupled nitrogen (N) fertigation and water salinity on clogging of emitters with plain channel and labyrinth structures. The results demonstrated that the H+ in acidic P fertilizer solutions inhibited the precipitation of carbonate and phosphate simultaneously. However, a weak acidic P fertilizer could no longer protect the emitters from clogging effectively under saline water with an electrical conductivity (EC) exceeding 2 dS m−1 because the phosphate sediments accounted for more than 80% of the total clogging substances. A strategy of applying a weak acidic phosphate fertilizer following N fertigation performs better in reducing emitter clogging than fertigation using N and phosphate fertilizers together. The target pH values were obtained as 6.0, 4.0, and 3.0 for protecting emitters from clogging for drip irrigation systems applying irrigation water with an EC of 0.5, 2.0, and 4.0 dS m−1, respectively. An optimal fertigation mode for emitter clogging control should consider water quality, type and pH value of fertilizer, and emitter type comprehensively.
Electromyography of diurnal bruxism during assessment and treatment
Authors: Ellement Jade K. , Virues‐Ortega Javier , Boris Ashley
Published: July 2021

Diurnal bruxism among individuals with intellectual disabilities is often measured on the basis of its auditory products, thereby precluding the contingent presentation of stimuli during silent bruxism events. Electromyography (EMG) offers a technological solution to the identification of all bruxism events. EMG has not been previously evaluated in nonvocal clients with intellectual disabilities in the context of functional analysis and treatment. In the current series of analyses, we suggest a set of methods to implement EMG technology with this population. In Analysis 1, we propose a strategy for systematically identifying bruxism events. In Analysis 2 we evaluate an EMG staff‐training package with naïve interventionists without past experience with EMG technology. Finally, Analysis 3 presents a practical example of this method during the functional analysis and treatment of a client with frequent diurnal bruxism.
The mediating role of psychological distress on the link between socio‐ecological factors and quality of life of Filipino adults during COVID‐19 crisis
Authors: Aruta John Jamir Benzon R. , Callueng Carmelo , Antazo Benedict G. , Ballada Christine Joy A.
Published: July 2021

Anchored on the Ecological Systems Theory, this study aimed to determine how psychological distress operates as an underlying mechanism in the impact of socio‐ecological factors on the quality of life of Filipino adults during coronavirus disease 2019 (COVID‐19) crisis. A cross‐sectional online survey was conducted to assess perceptions of 401 adults on socio‐ecological factors (i.e., safety at home, trust in public institutions, and financial difficulties), psychological distress, and quality of life during the early phase of COVID‐19 community quarantine in the Philippines. Using latent variable path analysis, all three socio‐ecological factors have significant direct effects on both psychological distress and quality of life. More importantly, the proposed model was confirmed in terms of a significant partial mediation of psychological distress on the impact of safety at home, trust in public institutions, and financial difficulties on the quality of life of Filipino adults. The study offers novel insights into the role of psychological distress as an underlying mechanism that operates on the influence of socio‐ecological factors on the quality of life of adults during a global health crisis. Implications on psychological interventions and policies in preventing mental health problems vis‐à‐vis improving Filipinos' quality of life during the COVID‐19 pandemic are discussed.
The evaluation of right ventricle dyssynchrony by speckle tracking echocardiography in systemic sclerosis patients
Authors: Demirci Murat , Ozben Beste , Sunbul Murat , Cincin Altug , Gurel Yusuf Emre , Bayram Guctekin Tuba , Dogan Zekeriya , Sahinkaya Yasemin , Direskeneli Haner , Tigen Kursat , Sayar Nurten
Published: July 2021

Purpose

Systemic sclerosis (SSc) is associated with right ventricle (RV) remodeling and dysfunction. The primary aim of this study was to evaluate RV dyssynchrony (RV‐Dys) in SSc patients using two‐dimensional speckle tracking echocardiography (2D‐STE).

Methods

Fifty‐five SSc patients with functional class I‐II and 45 healthy controls were consecutively included and underwent 2D‐STE. RV‐Dys was defined as the standard deviation of time to peak strain of mid and basal segments of RV free wall and interventricular septum. SSc group was further classified according to the presence of pulmonary arterial hypertension (PAH). Patients with tricuspid regurgitant velocity >2.8 m/s with additional echocardiographic PAH signs were defined as SSc PAH (+).

Results

SSc patients had lower RV longitudinal strain (RV‐LS) (−17.6 ± 4.6% vs. −20.8 ± 2.8%, p < 0.001) and greater RV‐Dys (49.9 ± 25.4 ms vs 24.3 ± 11.8 ms, p = 0.006) than controls despite no significant difference in conventional echocardiographic variables regarding RV function. Although SSc PAH(+) patients had lower RV‐LS and higher RV‐Dys than SSc PAH(−) patients, the differences were not statistically significant. The only independent predictor of RV‐Dys was RV‐LS (β:‐0.324 [−3.89– −0.45]; p = 0.014).

Conclusion

SSc patients had not only reduced RV‐LS but also impaired RV synchronicity even as conventional echocardiographic variables were preserved.
Comparing stimulus preference and response force in a conjugate preparation
Authors: Davis William T. , Rapp John T. , Brogan Kristen M. , Pinkston Jonathan W. , Chinnappan Barathi
Published: July 2021

Researchers used a conjugate preparation to evaluate how response force changed based on participants' preferences for visual stimuli. First, researchers used a verbal preference assessment to evaluate each participant's preference for viewing for five object categories of visual stimuli; this process identified high preference (HP) stimuli and low preference stimuli for most participants. Thereafter, researchers exposed each participant to the five stimulus categories in a randomized order while using a force dynamometer to measure their response force to increase visual clarity of each stimulus. Results indicate the majority of participants' HP stimuli corresponded to the stimulus category for which they exerted the highest mean force. These preliminary findings suggest conjugate preparations involving response force may provide another option for measuring the relative value of some stimulus events.
Development and validation of a siphoning prototype for surface runoff evaluation
Authors: Grando Douglas Luiz , Gatiboni Luciano Colpo , Dall'Orsoletta Daniel João , Schmitt Djalma Eugênio , Mumbach Gilmar Luiz , Souza Junior Abelino Anacleto de , Brignoli Fernando Marcos
Published: July 2021

The degradation of soil and water quality encourages research to assess the effects of rainfall on the losses of soil and chemical elements that result from surface runoff. In seasons of high surface runoff, the collectors must support the total volume drained or allow its correct estimation to avoid misinterpretation of the data. The present investigation aimed to develop and validate a compact and low‐cost system to quantify surface runoff, sediments, and chemical elements losses using the bucket‐siphon sampler system (BS3) siphoning method. The tests performed within the system used the runoff collected in a Nitisol or solutions constructed at the laboratory through mixing soil (i.e., Nitisol or Cambisol) with tap water. The BS3 method was efficient in estimating the total volume of water runoff and the concentration of sediments and P in the surface runoff. The maximum flow rate supported by the BS3 method, as presented here, is 0.035 L s–1, which considering a 10‐m² plot is equivalent to 12.6 mm h–1. Due to the craft characteristics of the system, we recommend the calibration of each unit built to obtain a precise ratio between the volume stored and discarded by the siphoning. The prototype developed here is suitable for quantifying runoff volume, sediment, and P losses in field plots and has been manufactured under US$15.00.
Temporary cessation of ibrutinib results in reduced grade 3‐4 infections and durable remissions—Interim analysis of an on‐off‐repeat Phase 1b/2 study in patients with chronic lymphocytic leukemia
Authors: Lundin Jeanette , Mulder Tom A. , Kättström Magdalena , Wästerlid Tove , Uddevik Anders , Mellstedt Håkan , Heimersson Kia , Hansson Lotta , Palma Marzia , Österborg Anders
Published: July 2021

Ibrutinib is used continuously in CLL. This phase 1b/2 study interim analysis explored on‐off‐repeat dosing to reduce toxicity. After 12 months, 16/22 patients (73%) remained in first off‐phase irrespective if initial CR/PR or TP53 aberration. Grade 3‐4 infections were reduced from 55% to 5% during a similarly long off‐phase (P < .01). Treg and exhausted T‐cells increased (P = .01). Six patients restarted ibrutinib at early progression and remain drug‐sensitive. Our interim analysis shows a durable off‐phase in most patients, with reduced infections and cost‐saving potential. If toxicity‐driven permanent cessation of ibrutinib will be affected will be explored in the extended study.
Toll‐like receptor 10 controls TLR2‐induced cytokine production in monocytes from patients with Parkinson's disease
Authors: da Rocha Sobrinho Hermínio Maurício , Saar Gomes Rodrigo , da Silva Delson José , Quixabeira Valéria Bernadete Leite , Joosten Leo A. B. , Ribeiro de Barros Cardoso Cristina , Ribeiro‐Dias Fátima
Published: July 2021

Peripheral inflammation, particularly mediated by monocytes, can cause neuroinflammation in Parkinson's disease (PD). We investigated the mechanism of TLR2‐induced cytokine impairment in peripheral monocytes from PD patients and the association between the presence of CD14+TLR10+ monocytes and PD severity. Peripheral blood mononuclear cells from PD patients and healthy individuals were evaluated for TLR expression on monocyte subsets (CD14 and CD16 expression) using flow cytometry. Moreover, cytokines were evaluated using flow cytometry after stimulation with Pam3Cys (TLR2/TLR1 agonist) in the absence or presence of neutralizing antibodies to TLR10. The severity of PD was assessed using the unified PD rating scale (UPDRS) and motor activity, anxiety (BAI), depression (BDI), and fatigue (PD Fatigue Scale‐16) scales. The frequency of CD14+TLR10+ monocytes and expression intensity of TLR2 and TLR10 were higher in patients with PD than healthy individuals. The frequency of intermediate monocytes (CD14++CD16+) was not significantly increased in patients with PD, but was the main monocyte subset expressing TLR10. The TLR2/TLR1‐impaired cytokine production (IL‐6, TNFα, IL‐8, and IL‐10) in PD patients was reversed by neutralizing TLR10. The high frequency of total CD14+TLR10+ monocytes was associated with a reduction in the severity of PD according to the evaluation of motor and nonmotor symptoms. Peripheral monocytes from patients with PD showed phenotypic and functional alterations. The expression of TLR10 on monocytes can protect against PD by controlling TLR2‐induced cytokine production. Furthermore, data suggested that a low frequency of CD14+TLR10+ monocytes indicates the severity of PD. The results identified new opportunities for the development of novel PD neuroprotective therapies.
Recent insights on astrocyte mechanisms in CNS homeostasis, pathology, and repair
Authors: Hart Christopher G. , Karimi‐Abdolrezaee Soheila
Published: July 2021

Astrocytes play essential roles in development, homeostasis, injury, and repair of the central nervous system (CNS). Their development is tightly regulated by distinct spatial and temporal cues during embryogenesis and into adulthood throughout the CNS. Astrocytes have several important responsibilities such as regulating blood flow and permeability of the blood‐CNS barrier, glucose metabolism and storage, synapse formation and function, and axon myelination. In CNS pathologies, astrocytes also play critical parts in both injury and repair mechanisms. Upon injury, they undergo a robust phenotypic shift known as “reactive astrogliosis,” which results in both constructive and deleterious outcomes. Astrocyte activation and migration at the site of injury provides an early defense mechanism to minimize the extent of injury by enveloping the lesion area. However, astrogliosis also contributes to the inhibitory microenvironment of CNS injury and potentiate secondary injury mechanisms, such as inflammation, oxidative stress, and glutamate excitotoxicity, which facilitate neurodegeneration in CNS pathologies. Intriguingly, reactive astrocytes are increasingly a focus in current therapeutic strategies as their activation can be modulated toward a neuroprotective and reparative phenotype. This review will discuss recent advancements in knowledge regarding the development and role of astrocytes in the healthy and pathological CNS. We will also review how astrocytes have been genetically modified to optimize their reparative potential after injury, and how they may be transdifferentiated into neurons and oligodendrocytes to promote repair after CNS injury and neurodegeneration.
To walk in beauty: Sustainable leadership, frugal innovation and environmental performance
Authors: Iqbal Qaisar , Ahmad Noor Hazlina , Li Zeyun , Li Yongmei
Published: July 2021

Considering the severe environmental climate in frontier Asia and the substantial role of the manufacturing industry for any economy, the present study investigates the mechanism of sustainable leadership‐environmental performance based on the upper echelon theory (UET). Data were collected from 500 employees of large manufacturing firms listed under the Pakistan Stock Exchange, Pakistan. The response rate in this study was 52.60%. Furthermore, structural equation modelling was adopted to test the proposed hypothesis. Based on the results, frugal innovation partially mediated sustainable leadership on environmental performance. The practical implications and limitations were also summarised in the study.
Stereotactic radiosurgery commissioning and QA test cases—A TG‐119 approach for Stereotactic radiosurgery
Authors: Culcasi Rebecca , Baran Geoffrey , Dominello Michael , Burmeister Jay
Published: July 2021

Purpose

To develop a standardized set of representative clinical treatment cases that pose a range of optimization problems for evaluating the plan quality and dosimetric accuracy within the commissioning process for linac‐based stereotactic radiosurgery (SRS).

Methods

Five test cases with increasing complexity were created to validate delivery accuracy in SRS commissioning similar to the approach used by AAPM TG‐119 in developing a test suite for IMRT commissioning. Standardized structure sets, planning goals, and delivery requirements were specified for each case including a small sphere target, irregular target, irregular target placed off‐axis, multi‐target, and abutting organs‐at‐risk (OARs). Various VMAT field arrangements including a single arc, two coplanar arcs, full arc and vertex half arc, and four noncoplanar arcs were tested to generate clinically appropriate treatment plans.

Results

The small spherical target was 1.0 cm in diameter. The irregular target was a clinical cavity (2.3 × 2.2 × 1.4 cm³) and was shifted 4.5 cm for the irregular target off‐axis case. The multi‐target case used the irregular target and four spherical targets representing metastases ranging 0.9 to 1.6 cm in diameter, placed up to 7.5 cm off‐axis. The abutting OARs case included an acoustic neuroma and target placed near the optic nerve. All spherical targets received 24 Gy and the cavity received 18 Gy. The abutting OAR cases included a 3.74 cc lesion adjacent to the brainstem receiving 13 Gy and a 1.11 cc lesion adjacent to the optic nerve receiving 12 Gy. All plans used a single‐isocenter placed at the target center or geometric center of multiple targets. Planning goals for all cases included constraints for the target and brain minus PTV, along with brainstem and optic nerve where applicable. Deliverability was assessed through ion chamber measurements, in addition to composite and per‐field planar measurements on Gafchromic film and small‐field diode array. A mean and SD for measured versus planned doses of 101.0% ± 2.9% was observed over the 14 ion chamber measurements. Mean and SD for gamma pass rates were 98.5% ± 2.2% and 97.1% ± 4.9% for film and diode array, respectively, for gamma criteria of 2% and 1 mm.

Conclusion

These cases could provide the preliminary groundwork for a novel benchmark for institutions to evaluate linac‐based SRS commissioning and delivery accuracy prior to clinical implementation. The rapid widespread implementation of linac‐based SRS, the complexity associated with dosimetry and delivery, and high‐profile treatment deviations that have already resulted from its use, highlight the importance of such a benchmark test suite. Comprehensive dosimetric measurements from this standardized set of SRS optimization problems were used to fine‐tune and understand the limitations of our SRS planning and delivery system and establish a set of baseline data for comparison with other delivery platforms.
Small‐field beam data acquisition, detector dependency, and film‐based validation for a novel self‐shielded stereotactic radiosurgery system
Authors: Pinnaduwage Dilini S. , Srivastava Shiv P. , Yan Xiangsheng , Jani Shyam S. , Jenkins Cesare , Barani Igor J. , Sorensen Stephen
Published: July 2021

Purpose

This study reports a single‐institution experience with beam data acquisition and film‐based validation for a novel self‐shielded sterotactic radiosurgery unit and investigates detector dependency on field output factors (OFs), off‐axis ratios (OARs), and percent depth dose (PDD) measurements within the context of small‐field dosimetry.

Methods

The delivery platform for this unit consists of a 2.7‐MV S‐band linear accelerator mounted on coupled gimbals that rotate around a common isocenter (source‐to‐axis distance [SAD] = 450 mm), allowing for more than 260 noncoplanar beam angles. Beam collimation is achieved via a tungsten collimator wheel with eight circular apertures ranging from 4 mm to 25 mm in diameter. Three diodes (PTW 60012 Diode E, PTW 60018 SRS Diode, and Sun Nuclear EDGE) and a synthetic diamond detector (PTW 60019 micro Diamond [µD] detector) were used for OAR, PDD, and OF measurements. OFs were also acquired with a PTW 31022 PinPoint ionization chamber. Beam scanning was performed using a 3D water tank at depths of 7, 50, 100, 200, and 250 mm with a source‐to‐surface distance of 450 mm. OFs were measured at the depth of maximum dose (dmax = 7 mm) with the SAD at 450 mm. Gafchromic EBT3 film was used to validate OF and profile measurements and as a reference detector for estimating correction factors for active detector OFs. Deviations in field size, penumbra, and PDDs across the different detectors were quantified.

Results

Relative OFs (ROFs) for the diodes were within 1.4% for all collimators except for 5 and 7.5 mm, for which SRS Diode measurements were higher by 1.6% and 2.6% versus Diode E. The µD ROFs were within 1.4% of the diode measurements. PinPoint ROFs were lower by >10% for the 4‐mm and 5‐mm collimators versus the Diode E and µD. Corrections to OFs using EBT3 film as a reference were within 1.2% for all diodes and the µD detector for collimators 10 mm and greater and within 2.0%, 2.8%, and 1.1% for the 7.5‐, 5‐, and 4‐mm collimators, respectively. The maximum difference in full width at half maximum (FWHM) between the Diode E and the other active detectors was for the 25‐mm collimator and was 0.09 mm (µD), 0.16 mm (SRS Diode), and 0.65 mm (EDGE). Differences seen in PDDs beyond the depth of dmax were <1% across the three diodes and the µD. FWHM and penumbra measurements made using EBT3 film were within 1.34% and 3.26%, respectively, of the processed profile data entered into the treatment planning system.

Conclusions

Minimal differences were seen in OAR and PDD measurements acquired with the diodes and the µD. ROFs measured with the three diodes were within 2.6% and within 1.4% versus the µD. Gafchromic Film measurements provided independent verification of the OAR and OF measurements. Estimated corrections to OFs using film as a reference were <1.6% for the Diode E, EDGE, and µD detector.
Monte Carlo evaluation of a LYSO‐based Compton camera using two origin ensemble algorithms with resolution recovery
Authors: Huang Hsuan‐Ming
Published: July 2021

Purpose

Due to the lack of depth‐of‐interaction information, a Compton camera made of lutetium‐yttrium orthosilicate (LYSO) crystals suffers from poor spatial resolution, which may lead to an unreliable range verification in proton therapy. The aim of this study is to evaluate the performance of a LYSO‐based Compton camera using the origin ensemble algorithm with resolution recovery (OE‐RR). We also proposed a regularized version of OE‐RR called ROE‐RR.

Methods

We simulated a two‐layer LYSO‐based Compton camera which was used to detect prompt gammas (PGs) produced by a proton beam irradiated on a water phantom. PG images reconstructed by the OE‐RR algorithm were evaluated and compared with those reconstructed by the proposed ROE‐RR algorithm.

Results

Our simulated results show that both the OE‐RR and ROE‐RR algorithms could provide an accurate estimate of the Bragg peak position, with a mean positioning error of 2.5 mm. Compared to the OE‐RR algorithm, the proposed ROE‐RR algorithm is less sensitive with respect to initial conditions and requires less iterations for converging to equilibrium. More importantly, the proposed ROE‐RR algorithm could provide better image quality than the OE‐RR algorithm, especially in low‐count data.

Conclusions

For LYSO‐based Compton cameras, using a resolution‐recovery image reconstruction algorithm is essential for reliable range verification.
Specific Borrmann classification in advanced gastric cancer by an ensemble multilayer perceptron network: a multicenter research
Authors: Wang Siwen , Dong Di , Zhang Wenjuan , Hu Hui , Li Hailin , Zhu Yongbei , Zhou Junlin , Shan Xiuhong , Tian Jie
Published: July 2021

Purpose

Borrmann classification in advanced gastric cancer (AGC) is necessarily associated with personalized surgical strategy and prognosis. But few radiomics research studies have focused on specific Borrmann classification, and there is yet no consensus regarding what machine learning methods should be the most effective.

Methods

A combined size of 889 AGC patients was retrospectively enrolled from two centers. Radiomic features were extracted from tumors manually delineated on preoperative computed tomography images. Two classification experiments (Borrmann I/II/III vs. IV and Borrmann II vs. III) were conducted. In each task, we combined three common feature selection methods and five typical machine learning classifiers to construct 15 basic classification models, and then fed the 15 predictions to a designed multilayer perceptron (MLP) network.

Results

In internal and external validation cohorts, the proposed ensemble MLP yielded good performance with area under curves of 0.767 and 0.702 for Borrmann I/II/III vs. IV, as well as 0.768 and 0.731 for Borrmann II vs. III. Considering the imbalanced distribution of four Borrmann types (I, 2.9%; II, 12.8%; III, 69.5%; IV, 14.7%), the ensemble MLP surpassed the overfitting barrier and attained fine specificity (0.667 and 0.750 for Borrmann I/II/III vs. IV; 0.714 and 0.620 for Borrmann II vs. III) and sensitivity (0.795 and 0.610 for Borrmann I/II/III vs. IV; 0.652 and 0.703 for Borrmann II vs. III). Also, survival analysis showed that patients could be significantly risk stratified by MLP predicted types in both experiments (p< 0.0001, log‐rank test).

Conclusions

This study proposed an MLP‐based ensemble learning architecture, which could identify Borrmann type IV automatically and improve the differentiation of Borrmann type II from III. The study provided a new view for specific Borrmann classification in clinical practice.
Feasibility and acceptability of a home‐based resistance training intervention in adolescent and young adult hematopoietic cell transplant survivors
Authors: Ketterl Tyler G. , Ballard Sheri , Bradford Miranda C. , Chow Eric J. , Jenssen Kari , Myers Sam , Rosenberg Abby R. , Van Doren Matt , Baker K. Scott
Published: July 2021

Background

Adolescent and young adult (AYA) hematopoietic cell transplantation (HCT) survivors are at increased risk of metabolic syndrome and lean body mass (LBM) deficits. Resistance training (RT) is a potential intervention to improve LBM, metabolic fitness, and reduce risk of cardiovascular disease.

Procedure

Eligible participants ages 13–39 years, 80–120 days post‐HCT, transfusion independent, and prednisone dose ≤1 mg/kg/day were approached. Baseline assessments of body composition (DXA), anthropometrics, and strength testing were completed and participants were taught a 12‐week, home‐based RT intervention with weekly remote coaching. Follow‐up assessments were at day +200 (FU1) and +365 post‐HCT (FU2). Feasibility targets were (a) 60% enrollment of approached patients, (b) 80% completion of weekly phone calls, and (c) 80% completion of the RT intervention and FU1 assessments. Acceptability was based on positive responses in qualitative interviews.

Results

Twenty of 31 (65%) eligible AYAs enrolled. Three participants failed to complete baseline measurements (2 = scheduling barriers, 1 = passive refusal) and four participants who completed baseline assessments did not receive the intervention (1 = medical reasons, 2 = no longer interested). Of those who completed baseline assessments, 13 received the intervention, completed 88.5% of coaching calls, and 11 (65%) completed FU1. LBM (kg) increased or remained unchanged in nine of nine participants with complete body composition data at FU1 (mean 1.1 kg; 95%CI: 0.4, 1.9). All participants who completed FU1 reported they would recommend the intervention to an AYA HCT survivor.

Conclusions

A home‐based RT intervention in AYA HCT survivors early post HCT is both feasible and acceptable and may maintain or increase LBM.
Imine‐based covalent organic framework as photocatalyst for visible‐light‐induced atom transfer radical polymerization
Authors: Fu Xiaoling , Lu Zhen , Yang Hongjie , Yin Xiangyu , Xiao Longqiang , Hou Linxi
Published: July 2021

Photoinduced atom transfer radical polymerization (ATRP) is an economical and environment‐friendly method for synthesizing polymers with pre‐designable structures and precise molecular weight. Although significant progress for copper‐mediated photoinduced ATRP has been achieved, several drawbacks still remain, such as poor electron transfer capability and absorption bands of photocatalysts near UV region. Herein, imine‐based covalent organic framework, TAPPy‐TPA‐COF, has been synthesized as potential heterogeneous photocatalyst for photoinduced ATRP. The “living” feature of polymerizations of methyl methacrylate (MMA) can be well controlled by efficiency maintain the balance between activation and inactivation of CuI and CuII. The chain extension experiments have further demonstrated the chain‐end fidelity of polymers. Meanwhile, the catalyst recycle experiments have revealed stability of TAPPy‐TPA‐COF toward ATRP processes. These results support the feasibility of using COFs as heterogeneous photocatalysts for copper‐mediated ATRP under visible light irradiation.
Herbicide resistance across the Australian continent
Authors: Busi Roberto , Beckie Hugh J , Bates Andy , Boyes Tim , Davey Chris , Haskins Barry , Mock Simon , Newman Peter , Porri Aimone , Onofri Andrea
Published: July 2021

BACKGROUND

Lolium rigidum is the weed of greatest economic impact in Australia due to its formidable capacity to evolve herbicide resistance. In this study, 579 field‐sampled L. rigidum populations were tested for resistance to 21 herbicides applied at the recommended rate. Nine herbicide treatments were binary mixtures.

RESULTS

A total of 15 876 individual resistance tests were conducted by screening two million seeds at the recommended label rate. The overall frequency of resistant populations was 31%, 14%, 71%, 6% and 0% in response to the post‐emergence herbicide treatments clethodim, clethodim + butroxydim, imazamox + imazapyr, glyphosate and paraquat, respectively. The resistance frequency to stand‐alone pre‐emergence wheat‐selective herbicides ranged from 10% to 34%. Conversely, the levels of resistance to pre‐emergence mixtures or stand‐alone propyzamide were significantly lower, ranging from 6% to 0%. In winter, the responses to glyphosate, paraquat, cinmethylin, prosulfocarb, pyroxasulfone and trifluralin were reassessed, with 7%, 0%, 0%, 21%, 21% and 28% as the respective resistance frequencies. South Australia and Victoria are identified as epicenters for L. rigidum population resistance to pyroxasulfone, whereas populations in New South Wales have the greatest resistance to glyphosate and in Western Australia to clethodim.

CONCLUSIONS

For the first time, resistance levels to stand‐alone herbicides and binary mixtures are geographically ranked across the Australian continent by benchmark statistical analysis of resistance frequencies and distribution. The extension of these results will raise awareness of rapidly emerging patterns of herbicide resistance, encouraging the adoption of cost‐effective modes of action and integration of diverse strategies for weed resistance management.
Event‐triggered feedback control for delayed singular jump systems based on sampled observer and exponential detector
Authors: Zhuang Guangming , Xia Jianwei , Ma Qian , Sun Wei , Wang Yanqian
Published: July 2021

This paper is intended to investigate the problem of event‐triggered feedback control for time‐varying delays singular jump systems based on sampled observer and exponential detector. By virtue of the designed event‐triggered control strategies, the state estimate signals are transmitted to the controller under the networked communication environment and aperiodic sampling scheme. The driving threshold is devised by exponentially decreasing function, which is used to guarantee not only the validity of event‐triggered strategy but also the admissibility of the delayed singular jump systems. Neoteric stochastic admissibility, stabilization and performance conditions are obtained in terms of linear matrix inequalities. Simulation examples including an oil catalytic cracking process are utilized to illustrate the validity and superiority of the proposed event‐triggered feedback control technique.
A graph convolutional neural network for gene expression data analysis with multiple gene networks
Authors: Yang Hu , Zhuang Zhong , Pan Wei
Published: July 2021

Spectral graph convolutional neural networks (GCN) are proposed to incorporate important information contained in graphs such as gene networks. In a standard spectral GCN, there is only one gene network to describe the relationships among genes. However, for genomic applications, due to condition‐ or tissue‐specific gene function and regulation, multiple gene networks may be available; it is unclear how to apply GCNs to disease classification with multiple networks. Besides, which gene networks may provide more effective prior information for a given learning task is unknown a priori and is not straightforward to discover in many cases. A deep multiple graph convolutional neural network is therefore developed here to meet the challenge. The new approach not only computes a feature of a gene as the weighted average of those of itself and its neighbors through spectral GCNs, but also extracts features from gene‐specific expression (or other feature) profiles via a feed‐forward neural networks (FNN). We also provide two measures, the importance of a given gene and the relative importance score of each gene network, for the genes' and gene networks' contributions, respectively, to the learning task. To evaluate the new method, we conduct real data analyses using several breast cancer and diffuse large B‐cell lymphoma datasets and incorporating multiple gene networks obtained from “GIANT 2.0” Compared with the standard FNN, GCN, and random forest, the new method not only yields high classification accuracy but also prioritizes the most important genes confirmed to be highly associated with cancer, strongly suggesting the usefulness of the new method in incorporating multiple gene networks.
A Highly Enantioselective Approach to Hydrocarbazole Derivatives Catalyzed by Diphenylmethylidene Bis(oxazoline)‐Ni(II) Complexes
Authors: Luo Jia‐yu , Chenzhang Peng‐fei , Lan Wenjie , Li Jia‐qi , Qin Zhaohai , Fu Bin
Published: July 2021

The first Ni(II)‐catalyzed asymmetric [4+2] cycloaddition of silyloxyvinylindoles with 2‐enoyl pyridines was successfully accomplished by using a diphenylmethylidene‐tethered bis(oxazoline). A series of optically active hydrocarbazole derivatives with three contiguous stereocenters were achieved in good yield with both high diastereo‐(>20 : 1) and enantioeselectivities (up to 97 % ee) under mild conditions. Moreover, various 2‐enoyl azaarenes were compatible with the reaction. A proposed mechanism was deducted.