bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of Slip and Heat and Mass Transfer Effects on Peristaltic motion of Power-law fluid Prone to the Tube
Authors: Subadra N. , Prasad K. Maruthi , Prasad Rao S. Ravi
Published: June 2020

Present study deals with the study of peristaltic motion of a power-law fluid with nanoparticles in a tube with permeable walls. Heat and mass transfer effects and slip effect are studied in this investigation. Axial velocity, pressure gradient and frictional force are expressed analytically and investigated various parameter effects on these flow variables. The present model revealed that, heat transfer coefficient and mass transfer coefficients increases in the region [-1, 0] and decreases in the region [0, 1] with the increase of thermophoresis parameter and shows an opposite behavior with the increase of Brownian motion parameter. Pressure drop increases with the increase of slip parameter. Frictional force decreases with the increase of slip parameter and converges to 1.
High space resolution µ-RWELL for high rate applications
Authors: Bencivenni G. , Felici G. , Gatta M. , Giovannetti M. , Morello G. , Poli Lener M. , de Oliveira R. , Ochi A. , Tskhadadze E.
Published: June 2020

The µ-RWELL is a single-amplification stage resisitive MPGD. The amplification element, realized on a polyimide foil micro-patterned with a high density blind-holes (wells), is embedded through a thin resistive film, in the readout PCB. The introduction of the resistive layer affects the charge spread on the readout electrodes and suppresses the transition from streamer to spark giving the possibility to achieve large gains (>104). As a drawback the capability to stand high particle fluxes is reduced. In order to get rid of such a limitation different resistive layouts with prompt current evacuation schemes have been designed. In this work we present the study of the performance of the high rate layouts done at PSI, together with the measurement of the space resolution for orthogonal and inclined tracks performed at CERN.
A flexible and effcient microscopic simulation of multiple GEM chamber based on Garfield++
Authors: Bellini V , Brio V , Cisbani E , Kmieć K , Lagamba L , Perrino R , Petta C , Re L , Sutera C
Published: June 2020

Microscopic simulations may bring a better understanding of the response of gaseous detectors. Such simulations are computationally demanding, due to the modelling of the low energy processes and to the high segmentation required for the 2D/3D field maps. In MPGD such maps can be much more complex than those of traditional multiwire chambers, due to the heterogeneous materials and more involute geometries, which break the simplifying symmetries featured in the latter. In order to investigate the performance of the triple GEM 2-dimensional tracking chambers being developed for high luminosity experiments with the Super BigBite Spectrometer at Jefferson Laboratory, we have set up a flexible and rather effcient multistep simulation processor based on either ANSYS or GMSH+ELMER for 3D CAD and electrostatic field modelling and then combined to Garfield++. Potential systematic effects from the 3D CAD modellers, the mesh generators and the electrostatic field solvers have been estimated with dedicated simulations; once these effects have been assessed, the results of the multistep approach have been compared to a simplified whole GEM chamber model.
Recent Developments on Precise Timing with the PICOSEC Micromegas Detector
Authors: Manthos I , Bortfeldt J , Brunbauer F , David C , Desforge D , Fanourakis G , Franchi J , Gallinaro M , García F , Giomataris I , Gustavsson T , Guyot C , Iguaz F J , Kebbiri M , Kordas K , Legou P , Liu J , Lupberger M , Maillard O , Maniatis I , Müller H , Niaouris V , Oliveri E , Papaevangelou T , Paraschou K , Pomorski M , Resnati F , Ropelewski L , Sampsonidis D , Schneider T , Schwemling P , Scorsone E , Sohl L , Van Stenis M , Thuiner P , Tsipolitis Y , Tzamarias S E , Veenhof R , Wang X , White S , Zhang Z , Zhou Y
Published: June 2020

The PICOSEC-Micromegas detector was developed for precise timing of the arrival of charged particles with a resolution bellow 30 ps. This contribution, after a brief introduction presents results concerning the PICOSEC-Micromegas response to single photoelectrons, estimation of the photoelectron yield of various photocathode types, as well as its performance to time the arrival of test beam muons. In addition, results based on detailed simulation studies and a stochastic model developed for the understanding of the detector are presented. Finally, results of studies related to the development of large scale PICOSEC-Micromegas detector for practical applications are also presented, in particular, the timing performance of a multi-channel PICOSEC prototype.
Performance of Prototype of Optically Readout TPC with a 55Fe source
Authors: Abritta Costa I. , Baracchini E. , Bellini F. , Benussi L. , Bianco S. , Caponero M. , Cavoto G. , Di Marco E. , Maccarrone G. , Marafini M. , Mazzitelli G. , Messina A. , Piccolo D. , Pinci D. , Renga F. , Rosatelli F. , Saviano G. , Tomassini S.
Published: June 2020

The performances of an optical readout of Time Projection Chambers (TPCs) with multiple Gas Electron Multipliers (GEMs) amplification stages are presented. The detector is characterized by using 55Fe photons converting inside a 7 litre sensitive volume detector in different electric field configurations. This prototype is developed as part of the R&D for the CYGNO project for an application to direct Dark Matter search by detection of tracks of nuclear recoils in the gas within the keV energy range.
Electron and ion transmission of the gating foil for the TPC in the ILC experiment
Authors: Kobayashi M , Ogawa T , Shoji A , Aoki Y , Ikematsu K , Gros P , Kawaguchi T , Arai D , Iwamura M , Katsuki K , Koto A , Yoshikai M , Fujii K , Fusayasu T , Kato Y , Kawada S , Matsuda T , Narita S , Negishi K , Qi H , Settles R D , Sugiyama A , Takahashi T , Tian J , Watanabe T , Yonamine R
Published: June 2020

We have developed a gating foil for the time projection chamber envisaged as a central tracker for the international linear collider experiment. It has a structure similar to the Gas Electron Multiplier (GEM) with a higher optical aperture ratio and functions as an ion gate without gas amplification. The transmission rate for electrons was measured in a counting mode for a wide range of the voltages applied across the foil using an 55Fe source and a laser in the absence of a magnetic field. The upper limit of the transmission rate for positive ions was estimated to be 3.36 ± 0.05 (stat. only)) × 10−4 from the measured electron transmission at a relatively low reverse bias voltage applied to the foil (ΔV =−15.5 V). The blocking power of the gating foil was confirmed to be high enough to suppress the influence of ion backflow.
CMS phase-II upgrade with GEM detector
Authors: Gola Mohit
Published: June 2020

The Large Hadron Collider (LHC) will be upgraded in several phases that will allow significant expansion of its physics program. The final luminosity of the accelerator is expected to exceed 5 × 1034cm−2s−1, five times more than the original design value. The CMS muon system must be able to sustain a physics program after the increase of luminosity and maintain sensitivity for electroweak physics for TeV scale searches similar to what was achieved up to now. To cope with the corresponding increase in background rates and trigger requirements, the installation of additional sets of muon detectors based on Gas Electron Multiplier (GEM) technology, referred to as GE2/1 and ME0, has been planned. The installation and commissioning of the GE2/1 chambers is scheduled in 2022, and for ME0 detectors are expected to be installed between 2022 to 2024. We present an overview of the Muon Spectrometer upgrade using GEM technology, a detailed description of the GE2/1 and ME0 upgrade in terms of design, pre-production chambers, mechanics, installation services etc. We will focus in particular on the novel solutions adopted for realization of the latter project, with a summary of the ongoing R&D activities
Efficiency of rejection of abnormal measurements of the phase difference in the survey location finder when receiving signals of the scanning radio-frequency source under the rough terrain
Authors: Anikin A S , Zakharov F N , Filimonov V A
Published: June 2020

The paper presents the results of a study on rejecting anomalously large direction-finding errors from the results of instantaneous measurements of the ratio of the amplitudes of the output signals of the receiving antennas. Bearing rejection algorithms are based on theoretical dependences obtained for the normal model of fluctuations of the quadrature components of the output signals of the receiving antennas. The efficiency of algorithm rejection is determined by the terrain of open and semi-enclosed routes and may reach 54 percent.
The emergence and evolution of the concept “coherent turbulence”
Authors: Nosov V V , Lukin V P , Nosov E V , Torgaev A V
Published: June 2020

The brief review of the emergence and evolution history of “coherent structure” and “coherent turbulence” concepts in the theory of turbulence is made. The review is based on the data of the world scientific literature and includes some results of the authors’ own long-term research on coherent turbulence.
Optimization of frequency discretization for diagnostic information at diagnostics of technical objects
Authors: Asadchiy A V , Soldatov A I , Soldatov A A , Kim O H
Published: June 2020

The block diagram of the monitoring device is presented. The operation principle of the monitoring device is described. The main units affecting the quality of the monitored signal reconstruction are shown. The analysis of the differentiating device and the voltage-controlled generator is carried out. The main characteristics of the differentiating device and the voltage-controlled oscillator are given and the quality of signal reconstruction is evaluated when their parameters change. The requirements for choosing the optimal value of the derivative time constant and the frequency range of the voltage-controlled generator are specified. A calculation example of the required RAM for recording and reconstruction of the monitored signal is shown.
Investigation of the emit source coordinates estimation accuracy using reflections from the ground clutter
Authors: Dubinin D V , Mescheryakov A A , Denisov V P , Rahimova A M , Bazarbay L A , Geringer V
Published: June 2020

The issues of improving the accuracy of determining the coordinates of a radio source by a single-position method due to the joint processing of multiple signals reflected from local objects are considered. The electronic terrain map was obtained on the basis of artificial images of a two-dimensional point-like reconstruction flow. The results of computer simulation are presented.
Estimation of the relative humidity in the troposphere using GNSS signals
Authors: Zakharov F N , Filimonov V A , Krasnenko N P , Anikin A S
Published: June 2020

The report presents the relative air humidity in the troposphere retrieved from signals of global navigation satellite systems. The estimate is based on information on the moisture retrieved from the value of the wet tropospheric delay. The wet delay is converted into the humidity. The results are compared with the data of direct measurements. The discrepancy between the calculated and measured humidity values is about 12 percent.
Layer-by-layer application of particles using acoustic levitation
Authors: Sukhanov D , Roslyakov S , Emelyanov F
Published: June 2020

A method of layer-by-layer deposition of particles on a flat surface using acoustic levitation in air is proposed. An acoustic field for particle levitation is created using four phased emitter arrays. A field distribution is created that ensures the levitation of particles in a flat layer in a rectangular grid. Using a sound-transparent mesh, particles are fed into the levitation area. The use of an additional focused lattice makes it possible to remove excess particles from the levitation region. Particles are deposited by refocusing the side gratings to a lower height, followed by turning off the field.
Testing the method for increasing the spatial resolution of satellite radiometric images in the L-band
Authors: Yashchenko A S
Published: June 2020

The results of testing a method for increasing the spatial resolution of satellite radiometric data in the L-band are presented. Data obtained by satellite-borne radiometer is characterized by low spatial resolution. The use of satellite radar data can increase the spatial resolution of radiometric images in the L-band to hundreds of meters. At the moment, the L-band radiometric data processing is possible with the use of radar data C-band. For this reason the method gives satisfactory results in the absence of cloudiness on the radar image.
Ammonia sensors based on resistive structures M–SnO2:Sb–M
Authors: Tsymbalov A V , Kalygina V M , Maksimova N K , Chernikov E V
Published: June 2020

The paper presents a comparison of the responses of sensors to ammonia in continuous heating and thermal cycling modes, and also shows the dependence of the response time of the sensors on the content NH3. Thin films of tin dioxide were obtained using RF magnetron sputtering, and then annealed in air at a temperature of 425°C for 24 hours. In thermal cycling, the temperature of the heating cycle remains constant 400 °C (duration of the heating cycle was 8 s). The temperature of the cooling cycle changes in the range 200 °C – 100 °C, but duration of cooling of the cooling cycle was remained constant of 5 s. It was shown that the thermal cycling mode has several advantages over the constant heating mode. The experiments showed that sensors based on SnO2:Sb have short response times – less than 3 seconds.
Research of directional microwave couplers under conditions of extreme changes in load parameters caused by active element failures and circuit breaks
Authors: Korotaev V M , Tuev V I
Published: June 2020

The results of the study of directional microwave couplers under conditions of extreme changes in load parameters are presented. Models are proposed in the form of equivalent circuits, mathematical relationships are obtained connecting the parameters of models and directional couplers, the results of comparison of model parameters and directional couplers in the microwave CAD system are shown, and experimental results are attached.
Universal installation for studying structural defects in electrical and optical fiber materials
Authors: Kalytka V A , Korovkin M V , Sh Madi P , Kalacheva S A , Sidorina E A
Published: June 2020

A universal device for experimentally studying the migration of microscopic structure defects and the features of dielectric relaxation is proposed. it allows using the thermo stimulated depolarization method, in combination with the measurement of the tangent of the angle of dielectric losses and the thermo stimulated polarization current, to perform dielectric spectroscopy of hydrogen-bonded crystals and perform analysis of the properties and parameters of structure defects. A smaller (in comparison with the existing installation) additional compact device for measuring small values of electrical capacitance and the tangent of the angle of dielectric losses, including an electrometer B7-30, was designed, measurement was carried out using a q-factor meter VM 560. When measuringtgδ > 0.1, the VM-507 device was used. An experimental methodology is proposed that allows, in combination with the method of minimizing the comparison function (MFC - method), with a high degree of accuracy, to calculate the molecular characteristics of structural defects in composite materials based on semiconductors and dielectrics used in the electrical and optical fiber industry, electric power and insulation technology.
Numerical simulation of wave processes in solid and gaseous media based on the particle dynamics
Authors: Sukhanov D , Kuzovova A
Published: June 2020

A method is proposed for the numerical simulation of acoustic processes and the motion of solids in gases based on the representation of media in the form of multiple particles. The behavior of particles is described by Newton’s equations of motion, and the strength of the interaction between particles depends on the distance between them. For gas particles, only the repulsive force is considered, and for particles of a solid force interaction ensures the equilibrium existence of a body-centered cubic lattice. The model allows one to calculate the propagation of acoustic waves and their effect on solids in a gaseous medium.
Whether and how the vapors of Al, Cu, Fe, and W influence the dynamics of apokamps
Authors: Tarasenko V F , Kuznetsov V S , Panarin V A , Skakun V S , Sosnin E A
Published: June 2020

The recent hypothesis about the initiation of red sprites in the Earth atmosphere in presence of metal atoms was verified. We have tested this hypothesis using Al, Cu, Fe, and W electrodes in laboratory apokamp discharges in air at a pressure of 45 and 760 Torr. Our experiments show that the electrode material does influence the apokamp dynamics. However, for Fe and W, compared to Al and Cu, the start voltage of an apokamp in pulse-repetition mode is higher and its length is shorter. The emission spectrum of apokamp discharges reveals lines of their metal electrodes. Thus, the experiments confirm the hypothesis on the contribution of metal vapors from burnt meteors to the initiation of red sprites in the Earth atmosphere.
Enhanced mid-to-late winter predictability of the storm track variability in the North Pacific as a contrast with the North Atlantic
Authors: Nie Yu , Ren Hong-Li , Scaife Adam A
Published: June 2020

The storm tracks are a major driver of regional extreme weather events. Using the daily output of reanalysis and a latest generation ensemble seasonal forecasting system, this study examines the interannual variability and predictability of the boreal winter storm tracks in the North Pacific and North Atlantic. In both basins, the leading mode of storm track variability describes a latitudinal shifting of the climatological storm tracks. The shifting mode is closely connected with the extratropical large-scale teleconnection patterns (i.e. Pacific-North America teleconnection and North Atlantic Oscillation).

The main predictability source for the shifting mode of the North Pacific storm tracks are the ENSO-related sea surface temperature anomalies. Assessment of the seasonal prediction skill further shows that the shifting mode of the North Pacific storm tracks is in general better predicted than that of the North Atlantic storm tracks likely due to stronger ENSO effects.

Our analyses also find that, through the modulations of ENSO and the subtropical jet, the shifting mode of the North Pacific storm tracks exhibit a mid-to-late winter predictability enhancement. During El Niño phases, the North Pacific subtropical jet shifts equatorward and becomes strongest in mid-to-late winter, which dominates the upper-level flow and guides the storm track most equatorward. We argue that the intensification and equatorward shift of the North Pacific subtropical jet in mid-to-late winter of El Niño years provide the main reason for the increased mid-to-late winter predictability for the storm tracks. The results imply that good representation of the background subtropical jet in models is important for winter climate prediction of storm tracks.
Long-term precipitation in Southwestern Europe reveals no clear trend attributable to anthropogenic forcing
Authors: Peña-Angulo D , Vicente-Serrano S M , Domínguez-Castro F , Murphy C , Reig F , Tramblay Y , Trigo R M , Luna M Y , Turco M , Noguera I , Aznárez-Balta M , García-Herrera R , Tomas-Burguera M , El Kenawy A
Published: June 2020

We present a long-term assessment of precipitation trends in Southwestern Europe (1850–2018) using data from multiple sources, including observations, gridded datasets and global climate model experiments. Contrary to previous investigations based on shorter records, we demonstrate, using new long-term, quality controlled precipitation series, the lack of statistically significant long-term decreasing trends in precipitation for the region. Rather, significant trends were mostly found for shorter periods, highlighting the prevalence of interdecadal and interannual variability at these time-scales. Global climate model outputs from three CMIP experiments are evaluated for periods concurrent with observations. Both the CMIP3 and CMIP5 ensembles show precipitation decline, with only CMIP6 showing agreement with long term trends in observations. However, for both CMIP3 and CMIP5 large interannual and internal variability among ensemble members makes it difficult to identify a trend that is statistically different from observations. Across both observations and models, our results make it difficult to associate any declining trends in precipitation in Southwestern Europe to anthropogenic forcing at this stage.
The Realization of Intelligent Knowledge Adaptive Learning Method in the Field of Substation Operation and Maintenance
Authors: Yin Jianlin , Liang Yali , Gao Qi , Liu Lu , Lei Yabin , Zhao Xilan
Published: June 2020

In view of the lack of targeted and personalized knowledge learning in existing substation operators, this paper proposes an intelligent adaptive knowledge learning method in the field of substation operation and maintenance. First, an adaptive knowledge learning system is established including domain model, user model, teaching model and adaptive engine. In the user model, the item response theory (IRT) is used to estimate the learner’s master degree of knowledge points contained in the domain model, and then their learning needs are obtained. Meanwhile, the Bayesian network method is used to speculate the cognitive style of learners. On the basis of a comprehensive consideration of learning needs and cognitive style, the particle swarm optimization algorithm (PSO) in the teaching model is used to recommend the optimal learning resource for learners to realize the high-efficiency personalized knowledge learning in substation operation and maintenance.
A Non-intrusive home load identification method based on adaptive reinforcement learning algorithm
Authors: Li Haoyang
Published: June 2020

At present, the load data collection of residential users mainly starts from the lower acquisition frequency, so the non-intrusive home load identification method based on low frequency sampling has attracted wide attention. However, low-frequency sampling has a low recognition accuracy when the training data set is small. Therefore, a non-intrusive home load identification method based on adaptive KNN reinforcement learning algorithm is proposed. The method firstly analyzes the state of the electrical appliance by KNN to obtain the initial HMM model, and then solves the HMM model by adaptive KNN reinforcement learning algorithm to obtain the optimal state transition strategy. This method reduces the model pair data. The dependence improves the recognition accuracy of the model and the adaptability to new data. Finally, the experimental verification is carried out by the low frequency data set AMPds. The results show that the method improves the state recognition accuracy of the electrical appliance and enhances the adaptability of the algorithm to new data.
Recursive-Biased-Generalized-Inverse Method for Thrust Allocation for Dynamic Positioning Vessels with Non-Rotatable Thrusters and Force Constraints
Authors: Zhao Bo , Xia Guoqing
Published: June 2020

This paper presents a novel method for thrust allocation for DP vessels with non-rotatable thrusters and force constraints. It uses a modified cost function of the thrust allocation problem for non-rotatable thruster and without force constraints, such that the force constraint can be handled. The proposed method runs in a recursive way to minimize the allocation error. The proposed method is different from the known methods in the literature. The completeness and continuity of the proposed algorithm are studied to verify the effectiveness of the proposed method.
Design of power well cover wireless monitoring system based on freeRTOS and NB-IoT technology
Authors: Wang Wei , Xie Tairong , Hu Xianhua
Published: June 2020

Power well cover monitoring system (PWC-MS) based on the embedded microprocessor ARM Cortex-M3 with FreeRTOS is proposed in this paper. The software functions of the terminal are divided into four tasks, namely, watchdog refresh and flag monitoring task, system status light task, non-debug sensor mode task, and debug sensor mode task. The priority levels of tasks depend on real-time requirement. The temperature and humidity sensor RS-WS-N01-2-2 and the dual-axis tilt sensor ADXL345 are adopted in the terminal and the sampling data is sent to the IoT (Internet of Things) platform via the NB-IoT communication module BC35-G. The software of application layer in the IoT platform is developed based on the Spring Cloud and database technology with Java language. User can get the real-time data through the Web page. Experiments show that the PWC-MS works well and the real-time alarm can be realized immediately.
A Mobile Robot Recognize Blurred Targets via an Improved Histogram Equalization
Authors: Zhang Longzhi , Wu Dongmei
Published: June 2020

Target recognition is a precondition for guiding robots to complete tasks. However, if the target is blurred, recognition will be difficult, which will lead to an inefficiency operation for robots. For the sake of improving the robot operation efficiency, it is essential to improve the image quality of recognized blurred target. Since image enhancement is taken as a powerful ways for improving image quality, it has gained largely attentions from researches. In fact, most of enhance methods are proposed based on histogram equalization, and until present, focus of research is still on improvements of histogram equalization. Hence, this paper proposes an improved histogram equalization for blurred targets in mobile robot recognition. Compared with the traditional histogram equalization methods, our method has less calculation time and better performance of real-time. Furthermore, the proposed approach also has strong robustness in blurred target recognition via a mobile robot.
On Computation of Fractional-Order Differentiations
Authors: Ebihara Soichiro , Hori Noriyuki
Published: June 2020

It is shown in this paper that the conventional approach for computing fractional-order differentiation using gamma-functions can lead to numerical difficulties and result in large errors. To overcome this issue, a new algorithm based on matrix computations is proposed. Typical simulation results are presented to explain the concepts and show that, while the gamma-function-based derivative diverges away from the analytical derivative, the proposed technique does not at least for the range of discrete-time periods tested. However, the computation time required with the proposed method is longer, at present, than the conventional method, and further research is on-going.
A decision-making technique for solving order allocation problem using a genetic algorithm
Authors: Ahmad Ijaz , Liu Yan , Javeed Danish , Ahmad Shahab
Published: June 2020

The selection of proper suppliers is one of the most complicated works of the purchasing department. Today, supplier selection includes different conflicting objectives. Because of contradictory multi-objective supplier selection is solving by using decision-making technique. This paper is presented a modified genetic algorithm by using a combination of crossover operators, Order crossover (OX), Simulated binary crossover (SBX) to assign the optimal order quantities to each supplier, with criteria of transportation cost, product quality, and delivery time with a quantity discount. The result shows that the modified genetic algorithm is an allocated optimal order for multi vendors with improves quality as well as less computational times.
Research on target detection of carrier-based aircraft based on deep convolutional neural network
Authors: Xingdong Zhu , Shaobing Tian , Jiali Fan , Zheng Wang , Tianqing Liu
Published: June 2020

Aiming at the problem that the aircraft carrier deck carrier is dense and easy to block, the carrier aircraft target is difficult to detect, and the detection effect is easily affected by the illumination condition and target scale. Based on the YOLO v3 target detection model, the loss function weighted and linear attenuation NMS strategy is proposed. The experimental results show that the proposed improved method can automatically and comprehensively extract the target characteristics of the carrier aircraft. Compared with the original YOLO v3 detection model, the improved model has a good detection effect on the occlusion aircraft target, the detection accuracy and speed can meet the actual needs, and the adaptability is strong under different illumination conditions and target scales, and the model is highly robust.
The Sturm-Liouville problem of two-body system
Authors: Luo Siwei
Published: June 2020

The two-body system is of great interest and complexity. To study the evolution of the two-body system under the influence of torque, a new Sturm-Liouville equation

Lu

′

′

+
Lu
=

1

L

is derived from the Newtonian mechanism. Its solutions and the eigenvalue problem are investigated.
Epidemiologists Count: The Role of Diversity and Inclusion in the Field of Epidemiology
Authors: Ðoàn Lan N , Bacong Adrian M , Ma Kris Pui Kwan , Morey Brittany N
Published: June 2020

We present interpretations of the idea that “epidemiologists count” in response to the current status of membership and diversity and inclusion efforts within the Society for Epidemiological Research (SER). We review whom epidemiologists count to describe the (mis)representation of SER membership and how categorizations of people reflect social constructions of identity and biases that exist in broader society. We argue that what epidemiologists count—how diversity and inclusion are operationalized—has real-world implications on institutional norms and how inclusive/non-inclusive environments are. Finally, we examine which epidemiologists count within the field and argue that inclusion can only be achieved when we address how resources and opportunities are distributed among epidemiologists. To improve diversity and inclusion within SER and beyond, we recommend that SER strengthen its commitment to diversity, inclusion, and equity by: 1) integrating this priority on all agendas; 2) enhancing efforts to improve self-awareness among members and accountability within the organization; 3) supporting the growth of a diversifying workforce in epidemiology; and 4) increasing the visibility of health disparities research and researchers in epidemiology.
Endozoochory of Chrysobalanus icaco (Cocoplum) by Gopherus polyphemus (Gopher Tortoise) facilitates rapid germination and colonization in a suburban nature preserve
Authors: Hanish Carolyn J , Velez Sebastian , Moore Jon A , Devin Anderson Corey
Published: June 2020

Some large-seeded plants lack effective seed dispersal agents when they are introduced as ornamental plants to new areas, but can rapidly colonize a landscape if seed dispersal functions are restored. We examined whether Gopherus polyphemus (Gopher Tortoise) facilitated the spread of Chrysobalanus icaco (Cocoplum; Chrysobalanaceae) over a 14-year period in a suburban nature preserve (in Jupiter, FL, USA) by: (i) comparing germination patterns among gut-passed, hand-depulped and whole fruit treatments, and (ii) testing hypotheses about environmental predictors of the spatial distribution of C. icaco, including information about G. polyphemus movement pathways and burrow locations. While we did not find a significant difference in the total proportion of C. icaco seeds that germinated in each treatment, time to event analysis revealed that seeds that were found in faeces germinated significantly earlier than seeds that were hand-depulped or that were planted as whole fruits, supporting a lone scarification effect. Point process modeling revealed that the density of C. icaco bushes was higher near G. polyphemus movement pathways and was lower inside Serenoa repens (Saw Palmetto) patches, supporting a positive effect of tortoise movement patterns on plant distributions. The density of C. icaco increased from west to east, consistent with westward dispersal from the four founder bushes on the east side of the study area. After removal of outliers, we also detected a negative association between C. icaco spatial density and G. polyphemus burrow density that was presumably explained by the fact that seeds defecated deep within burrows were unlikely to germinate and establish without secondary movement. The results suggest that G. polyphemus contributed to the rapid dispersal of C. icaco by scatter dispersal of seeds (via faeces) in areas where tortoises were active and that movement pathways provided suitable conditions for colonization. The spread of C. icaco by G. polyphemus over a relatively short period of time provides a valuable window into the earliest stages of the colonization process and further supports the role of Chelonians as effective seed dispersal agents for large-seeded plants.
Periprosthetic Fluid Analysis in the Diagnosis of Breast Implant Infections Using Cell Count and Differential
Authors: Stewart Christopher N , Liu Bill B , Zheng Eugene E , Tuttle Sue-Mi C
Published: June 2020

Background

One of the most devastating complications following implant-based breast reconstruction is periprosthetic infection. Making a prompt and accurate diagnosis has been a challenge as plastic surgeons are limited by nonspecific systemic markers of infection, clinical examination findings, or imaging modalities.

Objectives

The aim of this study is to evaluate the use of periprosthetic fluid using cell count and differential as an aid in the diagnosis of infection.

Methods

This is a retrospective chart review. The authors selected patients who underwent breast reconstruction and had periprosthetic fluid analysis during the previous 10 years based on CPT 89051 (cell count and differential, body fluid). Only patients with clinical concerns for infection were included (cellulitis, fever, etc.); all others were excluded.

Results

A total of 54 samples were included in the study. Twenty-seven samples were associated with periprosthetic breast infections based on positive cultures or intraoperative findings consistent with infection. On fluid analysis, those with infection had a significantly higher neutrophil percentage (84.2% vs 19.3%, P < 0.0001). A cutoff value of 77% neutrophils had a sensitivity of 89% and a specificity of 93% in diagnosing infection. Delayed treatment in patients with high neutrophil percentage was associated with poorer outcomes. Lastly, there was a strong correlation between higher neutrophil percentage and increased rate of capsular contracture.

Conclusions

Early and accurate diagnosis of periprosthetic breast infections can lead to earlier treatment and potentially improved the outcomes. Aspiration and analysis of periprosthetic fluid for neutrophil percentage can be a reliable method to guide clinical decision making.

Level of Evidence: 3
Solubility-Weighted Index: fast and accurate prediction of protein solubility
Authors: Bhandari Bikash K , Gardner Paul P , Lim Chun Shen
Published: June 2020

Motivation

Recombinant protein production is a widely used technique in the biotechnology and biomedical industries, yet only a quarter of target proteins are soluble and can therefore be purified.

Results

We have discovered that global structural flexibility, which can be modeled by normalized B-factors, accurately predicts the solubility of 12 216 recombinant proteins expressed in Escherichia coli. We have optimized these B-factors, and derived a new set of values for solubility scoring that further improves prediction accuracy. We call this new predictor the ‘Solubility-Weighted Index’ (SWI). Importantly, SWI outperforms many existing protein solubility prediction tools. Furthermore, we have developed ‘SoDoPE’ (Soluble Domain for Protein Expression), a web interface that allows users to choose a protein region of interest for predicting and maximizing both protein expression and solubility.

Availability and implementation

The SoDoPE web server and source code are freely available at https://tisigner.com/sodope and https://github.com/Gardner-BinfLab/TISIGNER-ReactJS, respectively. The code and data for reproducing our analysis can be found at https://github.com/Gardner-BinfLab/SoDoPE_paper_2020.

Supplementary information

Supplementary data are available at Bioinformatics online.
Development of WEE2 kinase inhibitors as novel non-hormonal female contraceptives that target meiosis†
Authors: Hanna Carol B , Mudaliar Deepti , John Kristen , Allen C Leigh , Sun Luxin , Hawkinson Jon E , Schönbrunn Ernst , Georg Gunda I , Jensen Jeffrey T
Published: June 2020

WEE2 oocyte meiosis inhibiting kinase is a well-conserved oocyte specific kinase with a dual regulatory role during meiosis. Active WEE2 maintains immature, germinal vesicle stage oocytes in prophase I arrest prior to the luteinizing hormone surge and facilitates exit from metaphase II arrest at fertilization. Spontaneous mutations at the WEE2 gene locus in women have been linked to total fertilization failure indicating that selective inhibitors to this kinase could function as non-hormonal contraceptives. Employing co-crystallization with WEE1 G2 checkpoint kinase inhibitors, we revealed the structural basis of action across WEE kinases and determined type I inhibitors were not selective to WEE2 over WEE1. In response, we performed in silico screening by FTMap/FTSite and Schrodinger SiteMap analysis to identify potential allosteric sites, then used an allosterically biased activity assay to conduct high-throughput screening of a 26 000 compound library containing scaffolds of known allosteric inhibitors. Resulting hits were validated and a selective inhibitor that binds full-length WEE2 was identified, designated GPHR-00336382, along with a fragment-like inhibitor that binds the kinase domain, GPHR-00355672. Additionally, we present an in vitro testing workflow to evaluate biological activity of candidate WEE2 inhibitors including; (1) enzyme-linked immunosorbent assays measuring WEE2 phosphorylation activity of cyclin dependent kinase 1 (CDK1; also known as cell division cycle 2 kinase, CDC2), (2) in vitro fertilization of bovine ova to determine inhibition of metaphase II exit, and (3) cell-proliferation assays to look for off-target effects against WEE1 in somatic (mitotic) cells.
Adipokines expression and epithelial cell polarity in normal and cancerous breast tissue
Authors: Coradini Danila , Gambazza Simone , Oriana Saro , Ambrogi Federico
Published: June 2020

Cell polarity is crucial for the correct structural and functional organization of epithelial tissue. Its disruption can lead to loss of the apicobasal polarity, alteration in the intracellular components, misregulation of the pathways involved in cell proliferation and cancer promotion. Very recent in vitro/in vivo findings demonstrated that obesity-associated alterations in tissue adipokines protein level negatively affect epithelial polarity. We performed an in silico study to investigate whether such alterations also occur in surgical samples. We aimed to explore the relationship among the expression of the genes coding for leptin (LEP), adiponectin (ADIPOQ), adipokine receptors (LEPR, ADIPOR1 and ADIPOR2), and a panel of polarity-associated genes in normal tissue from breast reduction mammoplasty, and a series of paired samples of histologically normal (HN) tissue and invasive cancer. Results indicated that, in normal tissue, the expression of adipokines and their receptors negatively correlated with that of the polarity-associated genes and GGT1, which codes for γ-glutamyl transferase (GGT) enzyme, a marker of cell distress and membrane disruption. This negative correlation progressively decreased in HN and cancerous tissue, and loss of correlation between ADIPOR2 and polarity-associated genes appeared the most noticeable alteration. Given the growing role of obesity in breast cancer etiology and the opposite action of leptin and adiponectin in epithelial tissue remodeling, ADIPOR2 loss could be addressed as a key mechanism leading to an unbalanced leptin stimulatory activity, subsequent cell polarity disruption and eventually tumor initiation, a finding that requires to be confirmed also at the protein level and with in vivo models.
Implementation of a Mandatory Influenza Vaccine Policy: A 10-Year Experience
Authors: Kitt Eimear , Burt Sharon , Price Susan M , Satchell Lauren , Offit Paul A , Sammons Julia S , Coffin Susan E
Published: June 2020

Background

Influenza vaccination of healthcare workers (HCWs) has been recommended for more than 30 years. In 2009, HCWs were designated as a priority group by the Centers for Disease Control and Prevention. Current HCW vaccination rates are 78% across all settings and reach approximately 92% among those employed in hospital settings. Over the last decade, it has become clear that mandatory vaccine policies result in maximal rates of HCW immunization.

Methods

In this observational 10-year study, we describe the implementation of a mandatory influenza vaccination policy in a dedicated quaternary pediatric hospital setting by a multidisciplinary team. We analyzed 10 years of available data from deidentified occupational health records from 2009–2010 through the 2018–2019 influenza seasons. Descriptive statistics were performed using Stata v15 and Excel.

Results

Sustained increases in HCW immunization rates above 99% were observed in the 10 years postimplementation, in addition to a reduction in exemption requests and healthcare-associated influenza. In the year of implementation, 145 (1.6%) HCWs were placed on temporary suspension for failure to receive the vaccine without documentation of an exemption, with 9 (0.06%) subsequently being terminated. Since then, between 0 and 3 HCWs are terminated yearly for failure to receive the vaccine.

Conclusions

Implementation of our mandatory influenza vaccination program succeeded in successfully increasing the proportion of immunized HCWs at a quaternary care children’s hospital, reducing annual exemption requests with a small number of terminations secondary to vaccine refusal. Temporal trends suggest a positive impact on the safety of our patients.
Intact Human Immunodeficiency Virus (HIV) Reservoir Estimated by the Intact Proviral DNA Assay Correlates With Levels of Total and Integrated DNA in the Blood During Suppressive Antiretroviral Therapy
Authors: Papasavvas Emmanouil , Azzoni Livio , Ross Brian N , Fair Matthew , Yuan Zhe , Gyampoh Kwasi , Mackiewicz Agnieszka , Sciorillo Amanda C , Pagliuzza Amelie , Lada Steven M , Wu Guoxin , Goh Shih Lin , Bahnck-Teets Carolyn , Holder Daniel J , Zuck Paul D , Damra Mohammad , Lynn Kenneth M , Tebas Pablo , Mounzer Karam , Kostman Jay R , Abdel-Mohsen Mohamed , Richman Douglas , Chomont Nicolas , Howell Bonnie J , Montaner Luis J
Published: June 2020

Accurate characterization of the human immunodeficiency virus (HIV) reservoir is imperative to develop an effective cure. HIV was measured in antiretroviral therapy-suppressed individuals using the intact proviral DNA assay (IPDA), along with assays for total or integrated HIV DNA, and inducible HIV RNA or p24. Intact provirus correlated with total and integrated HIV.
Trends in the Nontuberculous Mycobacterial Disease Mortality Rate in Japan: A Nationwide Observational Study, 1997–2016
Authors: Harada Ko , Hagiya Hideharu , Funahashi Tomoko , Koyama Toshihiro , Kano Mitsunobu R , Otsuka Fumio
Published: June 2020

Background

The incidence of nontuberculous mycobacterial (NTM) infections has been increasing worldwide, becoming a significant healthcare burden especially among elderly people. This study aimed to evaluate the trends in NTM-associated mortality in Japan.

Methods

This study used vital statistics data and data on all NTM-associated deaths (N = 18 814) among individuals aged ≥40 years in Japan from 1997 to 2016. We calculated the crude and age-adjusted mortality rates by age and sex and used joinpoint regression to analyze trends and estimate the average annual percentage change (AAPC). We compared crude NTM- and tuberculosis-associated mortality rates by sex.

Results

The overall crude annual mortality rate increased from 0.63/100 000/year in 1997 to 1.93/100 000/year in 2016 and was the highest among individuals aged 80–84 years. The AAPC of the crude mortality rates among men of all ages and women aged 40–59 years were stable but increased among women aged 60–79 years (3.5%; 95% confidence interval [CI], 2.8–4.3) and ≥80 years (4.3%; 95% CI, 3.7–4.9). Among men, the age-adjusted mortality rates did not show a significant trend, while among women, the rates increased over the study period (AAPC, 4.6%; 95% CI, 2.7–6.6). In women, the crude NTM-associated mortality rate exceeded the tuberculosis mortality rate in 2014, 2015, and 2016.

Conclusions

NTM mortality increased in Japan between 1997 and 2016, especially among the elderly female population. Given the increasing NTM-associated mortality and the susceptible aging population, public health authorities in Japan should pay greater attention to NTM infections.
Tricuspid valve geometry and right heart remodelling: insights into the mechanism of atrial functional tricuspid regurgitation
Authors: Utsunomiya Hiroto , Harada Yu , Susawa Hitoshi , Ueda Yusuke , Izumi Kanako , Itakura Kiho , Hidaka Takayuki , Shiota Takahiro , Nakano Yukiko , Kihara Yasuki
Published: June 2020

Aims 

We sought to investigate tricuspid valve (TV) geometry and right heart remodelling in atrial functional tricuspid regurgitation (AF-TR) as compared with ventricular functional TR with sinus rhythm (VF-TR).

Methods and results 

Transoesophageal 3D echocardiography datasets of the TV and right ventricle were acquired in 51 symptomatic patients with severe TR (AF-TR, n = 23; VF-TR, n = 28). Three-dimensional right ventricular (RV) endocardial surfaces were reconstructed throughout the cardiac cycle and then postprocessed using semiautomated integration and segmentation software to calculate position of papillary muscle (PM) tips. Compared with VF-TR, AF-TR had more dilated and posteriorly displaced annulus and less leaflet tethering angles with more prominent right atrium and smaller RV end-systolic volume. On the XY (annular) plane, the centre of annulus was getting closer towards the anterior and posterior PM tips and was going away from the medial PM tip caused by prominent annular dilatation in AF-TR. On the Z-axis, the position of each PM tip in AF-TR was not so much displaced apically as that in VF-TR. Multiple linear regression analyses revealed that right atrial volume and right atrial/RV end-systolic volume ratio were determinants of annular area and orientation in AF-TR, respectively (both P < 0.001). Additionally, the posteromedial-directed component of posterior PM tip position and the apically directed component of the position of all three PM tips were independently associated with TV tethering angles of each leaflet in AF-TR (all P < 0.02).

Conclusion 

Right heart remodelling and its association with 3D TV geometry differ entirely between AF-TR and VF-TR, which may offer distinctive therapeutic implication.