bluuebunny/crossref_metadata_2025 huggingface dataset:
Modifying Carbon Supports of Catalyst for the Oxygen Reduction Reaction in Vehicle PEMFCs
Authors: Xue Qiong , Yang Daijun , Jiang Lei , Li Bing , Ming Pingwen
Published: May 2021

For current carbon-supported Pt catalysts in vehicle proton exchange membrane fuel cells (PEMFCs), the insufficient stability and durability of carbon supports are severe limitations under operating conditions. This paper adopts the accelerated stress test (AST) method to study the carbon corrosion of catalysts, which is significant to efficiently select the catalysts supports in fuel cells. Graphitized carbon blacks with various surface properties are heated under different conditions, followed by evaluation of their antioxidation capacity with the AST. It is shown that optimally graphitized carbon blacks demonstrate superior stability, retaining a constant quinone/hydroquinone (QH) transition peak potential for over 70,000 AST cycles. A Pt catalyst supported on the selected graphitized carbon exhibits excellent durability at both the rotating disk electrode (RDE) and membrane electrode assembly (MEA) levels. The final specific mass activity (MA) of the optimum catalyst is 47.87 mA/mgPt, which is 2.06 times that of commercial Pt/C (23.31 mA/mgPt) in the RDE tests. The final maximum power density of the optimum catalyst is 525.68 mW/cm2, which is 305.52 mW/cm2 higher than that of commercial Pt/C after undergoing the AST during the MEA measurements. These results prove that the rational surface features of carbon supports play a vital role in improving the overall fuel cell performance by realizing uniform dispersion of Pt nanoparticles, resisting corrosion, and reinforcing metal–support interactions.
Hemorrhagic Ligamentum Flavum Cyst Associated with Adjacent Bone Erosion: an Uncommon Subtype of Juxta-Facet Cyst—a Case Presentation
Authors: Papadimitriou Kyriakos , Dalaqua Mariana , Simonin Alexandre , Fournier Jean-Yves , Huscher Karen
Published: May 2021

Ligamentum flavum cyst of the lumbar spine has seldom been described. The mechanism of formation of these cysts remains unknown, but it is thought to be part of the degenerative process. Although they are clearly visible on imaging studies, these cysts are frequently wrongly diagnosed as ganglion or synovial cysts. Bone erosion is rarely associated with this pathology. Most common symptom is back and radicular pain due to nerve root compression. We report a case of ligamentum flavum cyst associated with bone remodeling presented with back and radicular pain. It was correctly diagnosed pre-operatively and treated surgically with satisfactory clinical outcome.
Young Woman with Sudden-Onset Neck Pain and Quadriplegia: a Case Report
Authors: Ota Koshi , Ogawa Shoji , Fujii Kensuke , Oishi Yasuo , Oka Masahiro , Onishi Naoya , Ota Kanna , Sano Yohei , Yokoyama Hiroki , Takasu Akira
Published: May 2021

Introduction

Sudden-onset quadriplegia is a neurologic emergency that requires immediate management. Anterior spinal artery syndrome (ASAS) is rare, but can cause sudden-onset quadriplegia. Magnetic resonance imaging (MRI) is an essential imaging modality for diagnosing ASAS.

Case Presentation

A 31-year-old woman without previous medical history was transferred to our facility for further workup of sudden-onset neck pain with quadriplegia. Diffusion-weighted imaging (DWI) revealed hyperintense signals predominantly in grey matter with a decreased apparent diffusion coefficient (ADC). These findings strongly suggested ASAS with spinal cord infarction. Edaravone, heparin, and aspirin with steroid pulse therapy were immediately initiated. Twelve days in an intensive care unit was required for dyspnea. Symptoms gradually resolved with rehabilitation, but the patient was wheelchair-bound without bladder control and was transferred to a rehabilitation facility on hospital day 48.

Conclusion

A combination of DWI with ADC mapping of the spine should proceed as soon as possible to ensure appropriate management. Early treatment with edaravone, aspirin, and steroid pulse therapy may prove beneficial for ASAS.
A multi-response optimization of the multi-directional forging process for aluminium 7075 alloy using grey-based taguchi method
Authors: Obara C. , Mwema F. M. , Keraita J. N. , Shagwira H. , Obiko J. O.
Published: May 2021

The multi-directional forging process of aluminium alloy 7075 (AA 7075) is studied using Deform 3D Version 11.0 simulation software. This process results in grain refinement in the bulk material. The 7075 aluminium alloy is used widely in the aerospace and automobile industries. Thermomechanical processing affects the mechanical properties of this alloy. This study focuses on optimising process parameters that affect the multi-directional forging using simulation. In the Taguchi design of experiment, four-factors and five levels are selected. The process input parameters considered are temperature, the strain per pass, the plunger speed, and the friction coefficient (μ). From Taguchi’s orthogonal array, forging simulations are undertaken and analysed. The significance of the process output parameters: material damage, stress and strain are analysed by analysis of variance. The results show that the friction coefficient and strain per pass highly affect the stress/strain distribution. Grey relational analysis is adopted to determine the optimum process parameters. The results show that the optimal combination of parameters is: temperature (200 °C), plunger speed (5 mm/s), friction coefficient (0.6), and strain per pass (0.6). Confirmation of simulation is carried out using the optimum input parameters. From the simulation results, the grey relational grade's optimal parameters have the highest maximum effective strain of 5.57, maximum effective stress of 665 MPa, and maximum damage of 0.416 compared to other simulated results.
A deep learning based approach for trajectory estimation using geographically clustered data
Authors: Shrivastava Aditya , Verma Jai Prakash V , Jain Swati , Garg Sanjay
Published: May 2021

This study presents a novel approach to predict a complete source to destination trajectory of a vehicle using a partial trajectory query. The proposed architecture is scalable to extremely large-scale data with respect to the dense road network. A deep learning model Long Short Term Memory (LSTM) has been used for analyzing the temporal data and predicting the complete trajectory. To handle a large amount of data, clustering of similar trajectory data is used that helps in reducing the search space. The clusters based on geographical locations and temporal values are used for training different LSTM models. The proposed approach is compared with the other published work on the parameters as Average distance error and one step prediction accuracy The one-step prediction accuracy is as good as 81% and Distance error are .33 Km. Our proposed approach termed Clustered LSTM is outperforming in both the parameters when compared with other reported results. The proposed solution is a clustering-based predictive model that effectively contributes to accurately handle the large scale data. The outcome of this study leads to improvise the navigation systems, route prediction, traffic management, and location-based recommendation systems.
Gesture commands for controlling high-level UAV behavior
Authors: Akagi John , Morris T. Devon , Moon Brady , Chen Xingguang , Peterson Cameron K.
Published: May 2021

Directing groups of unmanned air vehicles (UAVs) is a task that typically requires the full attention of several operators. This can be prohibitive in situations where an operator must pay attention to their surroundings. In this paper we present a gesture device that assists operators in commanding UAVs in focus-constrained environments. The operator influences the UAVs’ behavior by using intuitive hand gesture movements. Gestures are captured using an accelerometer and gyroscope and then classified using a logistic regression model. Ten gestures were chosen to provide behaviors for a group of fixed-wing UAVs. These behaviors specified various searching, following, and tracking patterns that could be used in a dynamic environment. A novel variant of the Monte Carlo Tree Search algorithm was developed to autonomously plan the paths of the cooperating UAVs. These autonomy algorithms were executed when their corresponding gesture was recognized by the gesture device. The gesture device was trained to classify the ten gestures and accurately identified them 95% of the time. Each of the behaviors associated with the gestures was tested in hardware-in-the-loop simulations and the ability to dynamically switch between them was demonstrated. The results show that the system can be used as a natural interface to assist an operator in directing a fleet of UAVs.

Article highlights

A gesture device was created that enables operators to command a group of UAVs in focus-constrained environments.

Each gesture triggers high-level commands that direct a UAV group to execute complex behaviors.

Software simulations and hardware-in-the-loop testing shows the device is effective in directing UAV groups.
Energy properties of bamboo biomass and mate co-products
Authors: Rusch Fernando , de Abreu Neto Raul , de Moraes Lúcio Danielle , Hillig Éverton
Published: May 2021

Fossil fuels are being replaced by clean energy sources. Lignocellulosic biomass is considered an eco-friendly alternative, as it is a renewable raw material with high energy potential. In this context, the aim of this study was to determine the biomass energy properties of three bamboo species and mate. Thus, three species of bamboo (Bambusa vulgaris Var. Vittata, Dendrocalamus asper and Phyllostachys aurea) and Ilex paraguariensis co-products (branches and sticks) were performed. The particle size, basic density, moisture content volatiles content, ashes content, fix carbon, gross and net calorific value and energy density of these biomasses were evaluated. The biomasses analyzed here were considered suitable for energy purposes, in general, these presented volatile content between 75 and 85 %, fixed carbon content between 15 and 25% and ash content close to 1%. Average fix carbon content of all analyzed biomass was 16.13%. Ash content of Phyllostachys aurea, branches of Ilex paraguariensis and Dendrocalamus asper presented lower values, average of 1.63%. Bambusa vulgaris and Ilex paraguariensis sticks presented higher values, average of 2.65%. Phyllostachys aurea presented gross calorific value higher than, average of 19.35 MJ kg− 1. Bambusa vulgaris, Dendrocalamus asper, Ilex paraguariensis branches and sticks presented statistically equal values. Bambusa vulgaris, Dendrocalamus asper, Phyllostachys aurea showed net calorific value higher to the other analyzed materials and did not present statistical difference. Basic energy density of Phyllostachys aurea was higher to bamboo species. Ilex paraguariensis showed the lowest values with no statistical difference for branches and sticks.

Article highlights

Knowledge of biomass properties enables the use of residues in bioenergy production as an eco-friendly alternative.

Bamboo and Mate co-products have desirable characteristics and potential to produce bioenergy.

The energetic performance of bamboo biomass was superior when compared to the branches and sticks of Ilex paraguariensis.
New approach for localization and smart data transmission inside underground mine environment
Authors: RayChowdhury Ankita , Pramanik Ankita , Roy Gopal Chandra
Published: May 2021

This paper presents an approach to access real time data from underground mine. Two advance technologies are presented that can improve the adverse environmental effect of underground mine. Visible light communication (VLC) technology is incorporated to estimate the location of miners inside the mine. The distribution of signal to noise ratio (SNR) for VLC system is also studied. In the second part of the paper, long range (LoRa) technology is introduced for transmitting underground information to above the surface control room. This paper also includes details of the LoRa technology, and presents comparison of ranges with existing above the surface technologies.
Conjugate heat transfer performance of stepped lid-driven cavity with Al2O3/water nanofluid under forced and mixed convection
Authors: Janjanam Naveen , Nimmagadda Rajesh , Asirvatham Lazarus Godson , Harish R. , Wongwises Somchai
Published: May 2021

Two-dimensional conjugate heat transfer performance of stepped lid-driven cavity was numerically investigated in the present study under forced and mixed convection in laminar regime. Pure water and Aluminium oxide (Al2O3)/water nanofluid with three different nanoparticle volume concentrations were considered. All the numerical simulations were performed in ANSYS FLUENT using homogeneous heat transfer model for Reynolds number, Re = 100 to 500 and Grashof number, Gr = 5000, 13,000 and 20,000. Effective thermal conductivity of the Al2O3/water nanofluid was evaluated by considering the Brownian motion of nanoparticles which results in 20.56% higher value for 3 vol.% Al2O3/water nanofluid in comparison with the lowest thermal conductivity value obtained in the present study. A solid region made up of silicon is present underneath the fluid region of the cavity in three geometrical configurations (forward step, backward step and no step) which results in conjugate heat transfer. For higher Re values (Re = 500), no much difference in the average Nusselt number (Nuavg) is observed between forced and mixed convection. Whereas, for Re = 100 and Gr = 20,000, Nuavg value of mixed convection is 24% higher than that of forced convection. Out of all the three configurations, at Re = 100, forward step with mixed convection results in higher heat transfer performance as the obtained interface temperature is lower than all other cases. Moreover, at Re = 500, 3 vol.% Al2O3/water nanofluid enhances the heat transfer performance by 23.63% in comparison with pure water for mixed convection with Gr = 20,000 in forward step.
The value of facilitation in interdisciplinary socio-environmental team research
Authors: Graef Dana J. , Motzer Nicole , Kramer Jonathan G.
Published: May 2021

We propose that facilitation can be used as a research method to improve the collaborative synthesis of interdisciplinary teams’ socio-environmental work. As described in this communication, our approach to facilitation adapts to teams’ practical and conceptual needs as their research develops. Our synthetic practice of facilitating interdisciplinary meetings at the US National Socio-Environmental Synthesis Center (SESYNC) further emphasizes the importance of process, intentionality, and advance preparation. By combining facilitation fundamentals with research skills, it is possible to create the conditions for effective interdisciplinary integration.
Incidence and associated factors of post dural puncture headache after cesarean section delivery under spinal anesthesia in University of Gondar Comprehensive Specialized Hospital, 2019, cross sectional study
Authors: Ferede Yonas Admasu , Nigatu Yonas Addisu , Agegnehu Abatneh Feleke , Mustofa Salh Yalew
Published: May 2021

ABSTRACT

Background:

Post-Dural puncture headache is a major complication of neuraxial anesthesia that can occur following spinal and epidural anesthesia. It is, postural, and frontal and relieved when the patient is supine position and aggravated during standing, sitting, coughing. Therefore, we aimed to determine the incidence and factors associated with post dural puncture headache following cesarean section under spinal anesthesia.

Methods:

An institution based cross sectional study was conducted from March 01 to May 29, 2019. A total of 384 willing patients were included in the study after obtaining ethical consent. Data was entered and analyzed using Statistical Package for Social Sciences (SPSS) window version 20. Descriptive statistics, cross-tabs and binary logistic regression analysis were performed to identify the association between post dural puncture headache and independent variables. The strength of the association was presented using adjusted odds ratio with 95% confidence interval and p-value<0.05 was considered as statistically significant.

Results:

The incidence of post dural puncture headache was 31.3% (95% CI: 26.8, 35.9) with response rate of 92.5%. Majority of the patients who developed it were on the 2nd day with majority of the pain being moderate. In this study body mass index, Size of spinal needle, number of attempt and educational status of anesthetists were significantly associated with it.

Conclusion:

In this study non-obese patients, big spinal needles, repeated number of attempts and educational status of anesthetists were the independent associated risk factors for post dural puncture headache.

Highlights
Association Between Trimester and Outcomes after Cholecystectomy During Pregnancy
Authors: Cheng Vincent , Matsushima Kazuhide , Ashbrook Matthew , Matsuo Koji , Schellenberg Morgan , Inaba Kenji , Sandhu Kulmeet
Published: May 2021

BACKGROUND:

Conventional philosophy promotes the second trimester as the ideal time during pregnancy for cholecystectomy. However, literature supporting this belief is sparse. The purpose of this study is to examine the association of trimester and clinical outcomes after cholecystectomy during pregnancy.

STUDY DESIGN:

The National Inpatient Sample was queried for pregnant women who underwent cholecystectomy between October 2015 and December 2017. Patients were categorized by trimester. Multivariable logistic and continuous outcome regression models were used to evaluate the association of trimester and outcomes, including maternal and fetal complications, length of stay, and hospital charges. The primary outcome was any complication—a composite of specific clinical complications, each of which were designated as secondary outcomes.

RESULTS:

A total of 819 pregnant women satisfied our inclusion criteria. Of these, 217 (26.5%) were in the first trimester, 381 (47.5%) were in the second trimester, and 221 (27.0%) were in the third trimester. Median age was 27 years (interquartile range: 23–31 years). Compared with the second trimester, cholecystectomy during the first trimester was not associated with higher rates of complications (adjusted odds ratio [AOR] 0.88, 95% confidence interval [CI]: 0.47–1.63, p = 0.68). However, cholecystectomy during the third trimester was associated with a higher rate of preterm delivery (AOR 7.20, 95% CI 3.09–16.77, p < 0.001) and overall maternal and fetal complications (AOR 2.78, 95% CI 1.71–4.53, p < 0.001). Compared with the second trimester, the third trimester was associated with 21.3% higher total hospital charges (p = 0.003).

CONCLUSIONS:

Our results suggest that cholecystectomy can be performed in the first trimester without significantly increased risk of maternal and fetal complications, compared to the second trimester. In contrast, cholecystectomy during pregnancy should not be delayed until the third trimester.
Improving hand hygiene in hospitals: comparing the effect of a nudge and a boost on protocol compliance
Authors: van Roekel Henrico , Reinhard Joanne , Grimmelikhuijsen Stephan
Published: May 2021

Nudging has become a well-known policy practice. Recently, ‘boosting’ has been suggested as an alternative to nudging. In contrast to nudges, boosts aim to empower individuals to exert their own agency to make decisions. This article is one of the first to compare a nudging and a boosting intervention, and it does so in a critical field setting: hand hygiene compliance of hospital nurses. During a 4-week quasi-experiment, we tested the effect of a reframing nudge and a risk literacy boost on hand hygiene compliance in three hospital wards. The results show that nudging and boosting were both effective interventions to improve hand hygiene compliance. A tentative finding is that, while the nudge had a stronger immediate effect, the boost effect remained stable for a week, even after the removal of the intervention. We conclude that, besides nudging, researchers and policymakers may consider boosting when they seek to implement or test behavioral interventions in domains such as healthcare.
Does False Consciousness Necessarily Preclude Moral Blameworthiness?: The Refusal of the Women Antisuffragists
Authors: Wilson Lee
Published: May 2021

Social philosophers often invoke the concept of false consciousness in their analyses, referring to a set of evidence-resistant, ignorant attitudes held by otherwise sound epistemic agents, systematically occurring in virtue of, and motivating them to perpetuate, structural oppression. But there is a worry that appealing to the notion in questions of responsibility for the harm suffered by members of oppressed groups is victim-blaming. Individuals under false consciousness allegedly systematically fail the relevant rationality and epistemic conditions due to structural distortions of reasoning or knowledge practices, undermining their status as responsible moral agents.

But attending to the constitutive mechanisms and heterogeneity of false consciousness enables us to see how having it does not in itself render someone an inappropriate target of blame. I focus here on the 1889 antisuffragist manifesto “An Appeal against Female Suffrage,” arguing that its signatories, despite false consciousness, satisfy both conditions for ordinary blameworthiness. I consider three prominent signatories, observing that the irrationality characterization is unsustainable beyond group-level diagnoses, and that their capacity to respond appropriately to reasons was not compromised. Following recent work on epistemic injustice, I also argue that culpable mechanisms constituted their false consciousness, rendering them blameworthy for the Appeal.
Scaling of magnetic dissipation and particle acceleration in ABC fields
Authors: Chen Qiang , Nalewajko Krzysztof , Mishra Bhupendra
Published: May 2021

Using particle-in-cell numerical simulations with electron–positron pair plasma, we study how the efficiencies of magnetic dissipation and particle acceleration scale with the initial coherence length

$\lambda _0$

in relation to the system size

$L$

of the two-dimensional ‘Arnold–Beltrami–Childress’ (ABC) magnetic field configurations. Topological constraints on the distribution of magnetic helicity in two-dimensional systems, identified earlier in relativistic force-free simulations, that prevent the high-

$(L/\lambda _0)$

configurations from reaching the Taylor state, limit the magnetic dissipation efficiency to about

$\epsilon _{\textrm {diss}} \simeq 60\,\%$

. We find that the peak growth time scale of the electric energy

$\tau _{E,{\textrm {peak}}}$

scales with the characteristic value of initial Alfvén velocity

$\beta _{A,{\textrm {ini}}}$

like

$\tau _{E,\textrm {peak}} \propto (\lambda _0/L)\beta _{A,{\textrm {ini}}}^{-3}$

. The particle energy change is decomposed into non-thermal and thermal parts, with non-thermal energy gain dominant only for high initial magnetisation. The most robust description of the non-thermal high-energy part of the particle distribution is that the power-law index is a linear function of the initial magnetic energy fraction.
Vague eggs and tags: Prevelar merger in Seattle
Authors: Freeman Valerie
Published: May 2021

This study describes prevelar merger, the raising of low-front /æ, ɛ/ and lowering of mid-front /e/ before the voiced velar /ɡ/, in Seattle, Washington. In the most advanced part of this change in progress, all twenty speakers (age 18–62, half men, half women, all white) produced /ɛɡ/ and /eɡ/ (beg, vague) as upgliding diphthongs merged in F1 and F2 directly between their nonprevelar counterparts (dress, face). /æɡ/ (bag) was also diphthongal, but its height varied between speakers, with middle-aged men showing near-complete three-way merger with beg-vague and younger speakers raising less, suggesting reversal or avoidance of this component. Previous work lacked information about vague and thus described bag- and beg-raising as failing to reach the height of nonprevelar face. This study revealed that vague is lowered, creating a merger target for both raised beg and bag within a separate diphthongal prevelar subsystem.
HERBERT SPENCER’S CASE FOR FREE BANKING
Authors: Bragues George
Published: May 2021

Though now almost entirely forgotten, Herbert Spencer was among the most widely read thinkers during the late nineteenth century. As part of his system of synthetic philosophy, Herbert Spencer addressed the topics of money and banking. This philosophic system articulates a concept of justice based on the principle of equal freedom. Invoking this principle, Spencer rejected a government-superintended regime of money and banking as unjust. Instead, he morally favored a system of free banking. Spencer also defended this system on economic grounds. His argument was that banks could be self-regulating in their management of the money supply, on the condition that the government limit its activities in the financial sphere to the enforcement of contracts. While Spencer’s case is not beyond questioning on philosophic and political grounds, he offers a distinctive and forceful analysis.
Observation of an Intriguing Equatorial Plasma Bubble Event Over Indian Sector
Authors: Ghodpage R. N. , Gurav O. B. , Taori A. , Sau S. , Patil P. T. , Erram V. C. , Sripathi S.
Published: May 2021

We report an interesting Equatorial Plasma Bubbles (EPBs) event during the night of March 22–23, 2017. To investigate the dynamics of observed EPBs, we utilize multi‐instrument data obtained with all‐sky imager (ASI) from Panhala (16.48°N, 74.6°E, 11.1°N Dip. Lat.), Canadian Advanced Digital Ionosonde (CADI) from Tirunelveli (8.73°N, 77.7°E, 1.6°N Dip. Lat.) and ionospheric backscatter echoes data of Gadanki Ionospheric Radar Interferometer (GIRI) radar from Gadanki (13.5°N, 79.2°E, 6.5°N Dip. Lat.) over Indian regions. The optical observations from Panhala reveal clear signatures of EPBs from ∼1600 UT onwards and corresponding ESF occurrence is noted in CADI at Tirunelveli as well. Backscatter echoes are also recorded in Range time intensity map obtained by GIRI after ∼17:45 UT. On this night, two EPBs (EPB1 and EPB2) are observed with inter‐depletion distance of ∼600 km. The EPB1 drifts eastward throughout the night and evolves with time as bifurcated structures while the trailing EPB2 drifts eastward initially and eventually drifts westward. We believe that this is the first evidence of differential drifts of EPBs imaged through ASI over a narrow longitudinal zone over the Indian region.
Vertical Structure of the Arctic Spring Transition in the Middle Atmosphere
Authors: Matthias Vivien , Stober Gunter , Kozlovsky Alexander , Lester Mark , Belova Evgenia , Kero Johan
Published: May 2021

In the middle atmosphere, spring transition is the time period where the zonal circulation reverses from winter westerly to summer easterly which has a strong impact on the vertical wave propagation influencing the ionospheric variability. The spring transition can be rapid in form of a final sudden stratospheric warming (SSW, mainly dynamically driven) or slow (mainly radiatively driven) but also intermediate stages can occur. In most studies spring transitions are classified either by their timing of occurrence or by their vertical structure. However, all these studies focus exclusively on the stratosphere and it is not clear if and how pre‐winter conditions have an impact on when and how spring transitions take place. Here we classify the spring transitions regarding their vertical‐temporal development beginning in January and spanning the whole middle atmosphere in the core region of the polar vortex. This leads to five classes where the timing of the SSW in the preceding winter and a downward propagating Northern Annular Mode plays a crucial role. First, we use Microwave Limb Sounder satellite data to describe the five classes for recent single years, and then we use Modern‐Era Retrospective analysis for Research and Applications Version 2 reanalysis data for a composite analysis. The results show distinctive differences between the five classes in the months before the spring transition especially in the mesosphere. We hypothesize that this will help to improve the prediction of the spring transition. Additionally, meteor radar winds are used to link spring transition effects in the upper mesosphere and lower thermosphere with the stratospheric final warming.
Unified Criterion for Clear‐Water Local Scour Induced by Junction Flows and Wall Jets
Authors: Cheng Nian‐Sheng , Lu Yesheng , Wei Maoxing , Chiew Yee‐Meng
Published: May 2021

Local scour in a sediment bed varies depending on the type, size and shape of hydraulic structures, and the properties of approach flow and sediment particles. Published studies are hitherto confined primarily to empirical experiments based on particular types of hydraulic structure and there is almost no comparison of scour amongst different types of hydraulic structures. This study aims to provide an attempt to unify different types of clear‐water scour based on a new length scale, which is proposed to characterize the size of the large‐scale flow structure that governs scouring processes. The new length scale serves as a generalized hydraulic radius, which is applicable for all types of clear‐water scour related to junction flows at bridge piers and abutments, and wall jets including culverts. The analysis indicates that when normalized with the new length scale, the equilibrium scour depths can be described with a unified function of the densimetric Froude number, regardless of different scour types. In addition, this study also shows that the proposed function varies with the scour efficiency, in a fashion resembling the bedload function in the range of low to high transport regimes. This finding, which is founded on solid physical grounds, reveals that different kinds of local scour phenomena can be interpreted in unison rather than based on the individual type of hydraulic structures.
Myeloid-derived suppressor cell subtypes differentially influence T-cell function, T-helper subset differentiation, and clinical course in CLL
Authors: Ferrer Gerardo , Jung Byeongho , Chiu Pui Yan , Aslam Rukhsana , Palacios Florencia , Mazzarello Andrea Nicola , Vergani Stefano , Bagnara Davide , Chen Shih-Shih , Yancopoulos Sophia , Xochelli Aliki , Yan Xiao-Jie , Burger Jan A. , Barrientos Jacqueline C. , Kolitz Jonathan E. , Allen Steven L. , Stamatopoulos Kostas , Rai Kanti R. , Sherry Barbara , Chiorazzi Nicholas
Published: May 2021

Cancer pathogenesis involves the interplay of tumor- and microenvironment-derived stimuli. Here we focused on the influence of an immunomodulatory cell type, myeloid-derived suppressor cells (MDSCs), and their lineage-related subtypes on autologous T lymphocytes. Although MDSCs as a group correlated with an immunosuppressive Th repertoire and worse clinical course, MDSC subtypes (polymorphonuclear, PMN-MDSC, and monocytic, M-MDSCs) were often functionally discordant. In vivo, PMN-MDSCs existed in higher numbers, correlated with different Th-subsets, and more strongly associated with poor clinical course than M-MDSCs. In vitro, PMN-MDSCs were more efficient at blocking T-cell growth and promoted Th17 differentiation. Conversely, in vitro M-MDSCs varied in their ability to suppress T-cell proliferation, due to the action of TNFα, and promoted a more immunostimulatory Th compartment. Ibrutinib therapy impacted MDSCs differentially as well, since after initiating therapy, PMN-MDSC numbers progressively declined, whereas M-MDSC numbers were unaffected, leading to a set of less immunosuppressive Th cells. Consistent with this, clinical improvement based on decreasing CLL-cell numbers correlated with the decrease in PMN-MDSCs. Collectively, the data support a balance between PMN-MDSC and M-MDSC numbers and function influencing CLL disease course.
A drug-repositioning screen using splicing-sensitive fluorescent reporters identifies novel modulators of VEGF-A splicing with anti-angiogenic properties
Authors: Star Eleanor , Stevens Megan , Gooding Clare , Smith Christopher W. J. , Li Ling , Ayine Monica Lamici , Harper Steve J. , Bates David O. , Oltean Sebastian
Published: May 2021

Alternative splicing of the vascular endothelial growth factor A (VEGF-A) terminal exon generates two protein families with differing functions. Pro-angiogenic VEGF-Axxxa isoforms are produced via selection of the proximal 3′ splice site of the terminal exon. Use of an alternative distal splice site generates the anti-angiogenic VEGF-Axxxb proteins. A bichromatic splicing-sensitive reporter was designed to mimic VEGF-A alternative splicing and was used as a molecular tool to further investigate this alternative splicing event. Part of VEGF-A’s terminal exon and preceding intron were inserted into a minigene construct followed by the coding sequences for two fluorescent proteins. A different fluorescent protein is expressed depending on which 3′ splice site of the exon is used during splicing (dsRED denotes VEGF-Axxxa and EGFP denotes VEGF-Axxxb). The fluorescent output can be used to follow splicing decisions in vitro and in vivo. Following successful reporter validation in different cell lines and altering splicing using known modulators, a screen was performed using the LOPAC library of small molecules. Alterations to reporter splicing were measured using a fluorescent plate reader to detect dsRED and EGFP expression. Compounds of interest were further validated using flow cytometry and assessed for effects on endogenous VEGF-A alternative splicing at the mRNA and protein level. Ex vivo and in vitro angiogenesis assays were used to demonstrate the anti-angiogenic effect of the compounds. Furthermore, anti-angiogenic activity was investigated in a Matrigel in vivo model. To conclude, we have identified a set of compounds that have anti-angiogenic activity through modulation of VEGF-A terminal exon splicing.
Brain functional connectivity in children with developmental coordination disorder following rehabilitation intervention
Authors: Izadi-Najafabadi Sara , Rinat Shie , Zwicker Jill G.
Published: May 2021

Background

Children with developmental coordination disorder (DCD) show improved motor function after Cognitive Orientation to Occupational Performance (CO-OP) intervention; however, the neural basis for these improvements is unknown.

Methods

In this randomized waitlist-controlled trial, 78 children with DCD (with/without ADHD) were randomly assigned to either a treatment or waitlist group and underwent three resting-state MRI scans over six months. The treatment group received intervention between the first and second scan; the waitlist group received intervention between the second and third scan.

Results

After CO-OP intervention, children with DCD [13 male, 8 female; mean (SD) age: 10.0 (1.7) years] showed increased functional connectivity between the default mode network and right anterior cingulate gyrus (p < 0.01). Additional gains were noted at follow-up three months after the intervention, with greater functional connectivity between the dorsal attention network and precentral gyrus (p < 0.02). However, children with DCD + ADHD [18 male, 1 female; mean (SD) age: 10.0 (1.14) years] did not show brain changes following CO-OP.

Conclusion

For children with DCD, increased functional connectivity in networks associated with self-, emotion-, and attention-regulation may underlie motor skill improvements observed after CO-OP intervention. Modifications to the CO-OP protocol may be required to induce similar brain changes in children with DCD + ADHD.

Impact

This study provides neuroscientific evidence for the Cognitive Orientation to Occupational Performance (CO-OP) approach as an effective rehabilitation intervention to induce brain and behavioral changes in children with DCD.

While children with DCD ± ADHD showed improved motor function after CO-OP, only children with DCD showed brain changes after intervention.

Children with DCD showed increased functional connectivity in networks associated with self-, emotion-, and attention-regulation after the intervention.

Treatment modifications may be required to induce similar brain changes in children with DCD + ADHD.

Pediatricians are encouraged to refer children with DCD  with and without ADHD for CO-OP intervention to improve their motor skills.
Integrated proteomic and metabolomic analyses reveal the importance of aroma precursor accumulation and storage in methyl jasmonate-primed tea leaves
Authors: Shi Jiang , Wang Jiatong , Lv Haipeng , Peng Qunhua , Schreiner Monika , Baldermann Susanne , Lin Zhi
Published: May 2021

In response to preharvest priming with exogenous methyl jasmonate (MeJA), tea plants adjust their physiological behavior at the molecular level. The whole-organism reconfiguration of aroma formation from the precursor to storage is poorly understood. In this study, we performed iTRAQ proteomic analysis and identified 337, 246, and 413 differentially expressed proteins in tea leaves primed with MeJA for 12 h, 24 h, and 48 h, respectively. Furthermore, a total of 266 nonvolatile and 100 volatile differential metabolites were identified by utilizing MS-based metabolomics. A novel approach that incorporated the integration of extended self-organizing map-based dimensionality was applied. The vivid time-scale changes tracing physiological responses in MeJA-primed tea leaves are marked in these maps. Jasmonates responded quickly to the activation of the jasmonic acid pathway in tea leaves, while hydroxyl and glycosyl jasmonates were biosynthesized simultaneously on a massive scale to compensate for the exhausted defense. The levels of α-linolenic acid, geranyl diphosphate, farnesyl diphosphate, geranylgeranyl diphosphate, and phenylalanine, which are crucial aroma precursors, were found to be significantly changed in MeJA-primed tea leaves. Green leaf volatiles, volatile terpenoids, and volatile phenylpropanoids/benzenoids were spontaneously biosynthesized from responding precursors and subsequently converted to their corresponding glycosidic forms, which can be stably stored in tea leaves. This study elucidated the physiological response of tea leaves primed with exogenous methyl jasmonate and revealed the molecular basis of source and sink changes on tea aroma biosynthesis and catabolism in response to exogenous stimuli. The results significantly enhance our comprehensive understanding of tea plant responses to exogenous treatment and will lead to the development of promising biotechnologies to improve fresh tea leaf quality.
Integration of early disease-resistance phenotyping, histological characterization, and transcriptome sequencing reveals insights into downy mildew resistance in impatiens
Authors: Peng Ze , He Yanhong , Parajuli Saroj , You Qian , Wang Weining , Bhattarai Krishna , Palmateer Aaron J. , Deng Zhanao
Published: May 2021

Downy mildew (DM), caused by obligate parasitic oomycetes, is a destructive disease for a wide range of crops worldwide. Recent outbreaks of impatiens downy mildew (IDM) in many countries have caused huge economic losses. A system to reveal plant–pathogen interactions in the early stage of infection and quickly assess resistance/susceptibility of plants to DM is desired. In this study, we established an early and rapid system to achieve these goals using impatiens as a model. Thirty-two cultivars ofImpatiens wallerianaandI. hawkeriwere evaluated for their responses to IDM at cotyledon, first/second pair of true leaf, and mature plant stages. AllI. wallerianacultivars were highly susceptible to IDM. While allI. hawkericultivars were resistant to IDM starting at the first true leaf stage, many (14/16) were susceptible to IDM at the cotyledon stage. Two cultivars showed resistance even at the cotyledon stage. Histological characterization showed that the resistance mechanism of theI. hawkericultivars resembles that in grapevine and type II resistance in sunflower. By integrating full-length transcriptome sequencing (Iso-Seq) and RNA-Seq, we constructed the first reference transcriptome forImpatienscomprised of 48,758 sequences with an N50 length of 2060 bp. Comparative transcriptome and qRT-PCR analyses revealed strong candidate genes for IDM resistance, including three resistance genes orthologous to the sunflower geneRGC203, a potential candidate associated with DM resistance. Our approach of integrating early disease-resistance phenotyping, histological characterization, and transcriptome analysis lay a solid foundation to improve DM resistance in impatiens and may provide a model for other crops.
Auxin-induced AUXIN RESPONSE FACTOR4 activates APETALA1 and FRUITFULL to promote flowering in woodland strawberry
Authors: Dong Xiangxiang , Li Yanjun , Guan Yuhan , Wang Shaoxi , Luo He , Li Xiaoming , Li He , Zhang Zhihong
Published: May 2021

Flowering time is known to be regulated by numerous pathways, such as the autonomous, gibberellin, aging, photoperiod-mediated, and vernalization pathways. These regulatory mechanisms involve both environmental triggers and endogenous hormonal cues. Additional flowering control mechanisms mediated by other phytohormones, such as auxin, are less well understood. We found that in cultivated strawberry (Fragaria × ananassa), the expression of auxin response factor4 (FaARF4) was higher in the flowering stage than in the vegetative stage. Overexpression of FaARF4 in Arabidopsis thaliana and woodland strawberry (Fragaria vesca) resulted in transgenic plants flowering earlier than control plants. In addition, FveARF4-silenced strawberry plants showed delayed flowering compared to control plants, indicating that FaARF4 and FveARF4 function similarly in regulating flowering. Further studies showed that ARF4 can bind to the promoters of the floral meristem identity genes APETALA1 (AP1) and FRUITFULL (FUL), inducing their expression and, consequently, flowering in woodland strawberry. Our studies reveal an auxin-mediated flowering pathway in strawberry involving the induction of ARF4 expression.
A nondestructive Bell-state measurement on two distant atomic qubits
Authors: Welte Stephan , Thomas Philip , Hartung Lukas , Daiss Severin , Langenfeld Stefan , Morin Olivier , Rempe Gerhard , Distante Emanuele
Published: May 2021

One of the most fascinating aspects of quantum networks is their capability to distribute entanglement as a nonlocal communication resource1. In a first step, this requires network-ready devices that can generate and store entangled states2. Another crucial step, however, is to develop measurement techniques that allow for entanglement detection. Demonstrations for different platforms3–13 suffer from being not complete, destructive or local. Here, we demonstrate a complete and nondestructive measurement scheme14–16 that always projects any initial state of two spatially separated network nodes onto a maximally entangled state. Each node consists of an atom trapped inside an optical resonator from which two photons are successively reflected. Polarization measurements on the photons discriminate between the four maximally entangled states. Remarkably, such states are not destroyed by our measurement. In the future, our technique might serve to probe the decay of entanglement and to stabilize it against dephasing via repeated measurements17,18.
Endodontic length measurements using cone beam computed tomography with dedicated or conventional software at different voxel sizes
Authors: Van Pham Khoa
Published: May 2021

The aim of this study is to investigate the accuracies and the agreements of the 3D Endo software, conventional CBCT software Romexis Viewer at three voxel sizes, and the EAL ProPex Pixi in endodontic length measurements. Three hundred and twenty-nine root canals in 120 intact human extracted molars were accessed. The actual lengths (AL) and electronic lengths (EL) were measured using the ruler and electronic apex locator (EAL), respectively. Teeth were scanned using the CBCT at different voxel sizes (0.075, 0.10, and 0.15 mm). Root canal lengths were measured using 3D Endo with proposed length (3D-PL) by software, corrected length (3D-CL), Romexis Viewer. The Fisher’s exact test, paired t-test and Bland–Altman plots were calculated to detect the agreements of the four methods with AL measurements. The ProPex Pixi measurements obtained the highest accuracy in the range of ± 0.5 mm. There was agreement between the 3D-PL and the 3D-CL with AL measurements at voxel size of 0.15 mm and at voxel size of 0.10 mm, respectively. The CBCT Romexis Viewer measurements agreed with AL at three voxel sizes. The conventional CBCT measurements using Romexis Viewer and dedicated software did not reach to the 100% accuracy in the range of ± 0.5 mm.
Publisher Correction: Comparison of two different doses of bleomycin in electrochemotherapy protocols for feline cutaneous squamous cell carcinoma nonsegregated from ultraviolet light exposure
Authors: Dos Anjos Denner S. , Sierra Oscar R. , Spugnini Enrico P. , De Nardi Andrigo B. , Fonseca-Alves Carlos E.
Published: May 2021

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Author Correction: Linking human male vocal parameters to perceptions, body morphology, strength and hormonal profiles in contexts of sexual selection
Authors: Schild Christoph , Aung Toe , Kordsmeyer Tobias L. , Cardenas Rodrigo A. , Puts David A. , Penke Lars
Published: May 2021

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Worker ants promote outbreeding by transporting young queens to alien nests
Authors: Vidal Mathilde , Königseder Florian , Giehr Julia , Schrempf Alexandra , Lucas Christophe , Heinze Jürgen
Published: May 2021

Choosing the right mating partner is one of the most critical decisions in the life of a sexually reproducing organism and is the basis of sexual selection. This choice is usually assumed to be made by one or both of the sexual partners. Here, we describe a system in which a third party – the siblings – promote outbreeding by their sisters: workers of the tiny ant Cardiocondyla elegans carry female sexuals from their natal nest over several meters and drop them in the nest of another, unrelated colony to promote outbreeding with wingless, stationary males. Workers appear to choose particular recipient colonies into which they transfer numerous female sexuals. Assisted outbreeding and indirect female choice in the ant C. elegans are comparable to human matchmaking and suggest a hitherto unknown aspect of natural history – third party sexual selection. Our study highlights that research at the intersection between social evolution and reproductive biology might reveal surprising facets of animal behavior.
Environmental DNA provides higher resolution assessment of riverine biodiversity and ecosystem function via spatio-temporal nestedness and turnover partitioning
Authors: Seymour Mathew , Edwards François K. , Cosby Bernard J. , Bista Iliana , Scarlett Peter M. , Brailsford Francesca L. , Glanville Helen C. , de Bruyn Mark , Carvalho Gary R. , Creer Simon
Published: May 2021

Rapidly assessing biodiversity is essential for environmental monitoring; however, traditional approaches are limited in the scope needed for most ecological systems. Environmental DNA (eDNA) based assessment offers enhanced scope for assessing biodiversity, while also increasing sampling efficiency and reducing processing time, compared to traditional methods. Here we investigated the effects of landuse and seasonality on headwater community richness and functional diversity, via spatio-temporal dynamics, using both eDNA and traditional sampling. We found that eDNA provided greater resolution in assessing biodiversity dynamics in time and space, compared to traditional sampling. Community richness was seasonally linked, peaking in spring and summer, with temporal turnover having a greater effect on community composition compared to localized nestedness. Overall, our assessment of ecosystem function shows that community formation is driven by regional resource availability, implying regional management requirements should be considered. Our findings show that eDNA based ecological assessment is a powerful, rapid and effective assessment strategy that enables complex spatio-temporal studies of community diversity and ecosystem function, previously infeasible using traditional methods.