bluuebunny/crossref_metadata_2025 huggingface dataset:
A new hypothesis-testing model for phyllochron based on a stochastic process - application to analysis of genetic and environment effects in maize
Authors: Plancade S. , Marchadier E. , Huet S. , Ressayre A. , Noûs C. , Dillmann C.
Published: January 2021

The times between appearance of successive leaves or phyllochron characterize the vegetative development of annual plants. Hypothesis testing models, which enables to compare phyllochron between genetic groups or conditions, are usually based on regression of thermal time on the number of leaves, most of the time assuming a constant leaf appearance rate. However these models are both statistically biased and inappropriate in terms of modelling. We propose a stochastic process model in which the emergence of new leaves is considered as successive time-to-events, which provides a flexible and more accurate modelling as well as unbiased testing procedures. The model was applied on an original maize dataset collected in fields for three years on plants originating from two divergent selection experiments for flowering time conducted in two maize inbred lines. We showed that the main differences in phyllochron were not observed between selection populations (Early or Late), but rather between ancestral lines, years of experimentation, and leaf ranks. Our results highlight a strong departure from the assumption of a constant leaf appearance rate in one year that could be related to climate variations, even if the impact of each climatic variables individually was not clearly elucidated.
A single mutation attenuates both the transcription termination and RNA-dependent RNA polymerase activity of T7 RNA polymerase
Authors: Wu Hui , Wei Ting , Cheng Rui , Huang Fengtao , Lu Xuelin , Yan Yan , Yu Bingbing , Wang Xionglue , Liu Chenli , Zhu Bin
Published: January 2021

Transcription termination is one of the least understood processes of gene expression. As the prototype model for transcription studies, the single-subunit T7 RNA polymerase (RNAP) was known to response to two types of termination signals, while the mechanism underlying such termination especially the specific elements of the polymerase involved in is still unclear, due to the lack of a termination complex structure. Here we applied phage-assisted continuous evolution to obtain variants of T7 RNAP that can bypass the typical class I T7 terminator with stem-loop structure. Throughin vivoselection andin vitrocharacterization, we discovered a single mutation S43Y that significantly decreased the termination efficiency of T7 RNAP at all transcription terminators tested. Coincidently, the S43Y mutation almost eliminates the RNA-dependent RNA polymerase (RdRp) of T7 RNAP without affecting the major DNA-dependent RNA polymerase (DdRp) activity of the enzyme, indicating the relationship between transcription termination and RdRp activity, and suggesting a model in which the stem-loop terminator induces the RdRp activity which competes with the ongoing DdRp activity to cause transcription termination. The T7 RNAP S43Y mutant as an enzymatic reagent forin vitrotranscription reduces the undesired termination in run-off RNA synthesis and produces RNA with higher terminal homogeneity.
The Influence of Phosphorus and Transplanting Date on Onion (Allium CepaL.) Quality Parameters and yield of bulb Under Irrigation at Adami Tulu Jedo Kombolcha Woreda, East showa zone, Oromia Region
Authors: Anbes Tilaye , Worku Walelign
Published: January 2021

A field experiment was showed to decide the influence of phosphorus level and transplanting date on quality parameters of onion at Adami Tulu Jedo Kombolcha Woreda, during 2017/18 season. The treatments consisted of four phosphorus levels (0, 20, 40 and 60 kg P ha−1) and three transplanting date (42, 49 and 56 days). The experiment was laid out in randomized complete block design with four replications. The result showed that phosphorus level and transplanting date significantly influenced bulb dry matter content, marketable bulb yield, medium size bulb yield. Among these parameters, marketable bulb yield was also significantly influenced by the interaction of phosphorus level and transplanting date. On the other hand, small size bulb yield, large size bulb yield, over size bulb yield and under size bulb yield were only influenced by the effect of phosphorus levels. In this study, fertilized 60 kg P ha−1with transplanting at 56 days of transplanting date recorded the highest marketable bulb yield, but no significant difference was showed with that obtained at 40 kg P ha−1with the same transplanting date. Treatment combinations of no P (control) and transplanting date at 42 days produced the lowest amounts of marketable bulb yield. The economic analysis revealed that the highest net benefit with low cost of production was obtained in response to the application of 40 kg P ha−1and the transplanting age of 56 days. The marginal rate of return for this treatment was 11983% which is found to be economically feasible for producing bulb in the districts.
Refractory alveolar rhabdomyosarcoma in an 11-year-old male
Authors: Ricker Cora A. , Woods Andrew D. , Simonson William , Lathara Melvin , Srinivasa Ganapati , Rudzinski Erin R. , Mansoor Atiya , Irwin Robert G. , Keller Charles , Berlow Noah E.
Published: January 2021

Rhabdomyosarcoma (RMS) is a mesenchymal malignancy phenocopying muscle and is among the leading causes of death from childhood cancer. Metastatic alveolar rhabdomyosarcoma is the most aggressive subtype with an 8% 5-yr disease-free survival rate when a chromosomal fusion is present and a 29% 5-yr disease-free survival rate when negative for a fusion event. The underlying biology ofPAX-fusion-negative alveolar rhabdomyosarcoma remains largely unexplored and is exceedingly rare in Li–Fraumeni syndrome patients. Here, we present the case of an 11-yr-old male with fusion-negative alveolar rhabdomyosarcoma studied at end of life with a comprehensive functional genomics characterization, resulting in identification of potential therapeutic targets for broader investigation.
The structure of Ce2Al3Ge4 refined for the first time from single-crystal X-ray diffraction data
Authors: Tobash Paul , Bobev Svilen
Published: January 2021

Single crystals of dicerium trialuminium tetragermanide, Ce2Al3Ge4, have been synthesized from a high-temperature reaction using an eutectic mixture of Al and Ge as a metal flux. Through single-crystal X-ray diffraction it was established that Ce2Al3Ge4 crystallizes in the centrosymmetric space group Cmce (No. 64) with the Ba2Cd3Bi4 structure type (Pearson code oC36). Five atoms compose the asymmetric unit, i.e. one Ce, two Al, and two Ge atoms, all in special positions with Wyckoff symbols 8f (Ce), 4a and 8e (Al), and 8e and 8f (Ge). The structure can be described as a three-dimensional network of Al and Ge atoms, with Ce atoms occupying the cavities of the framework.
Development of a French‐language early literacy scale: structural analysis and links between the dimensions of early literacy
Authors: Thomas Aude , Tazouti Youssef , Hoareau Lara , Luxembourger Christophe , Hubert Blandine , Fischer Jean‐Paul , Jarlégan Annette
Published: January 2021

Background

The development of early literacy skills in preschoolers is an important predictor of future academic performance. Four main domains of early literacy are currently observed: letter knowledge, vocabulary, phonological awareness and oral comprehension. A multiplicity of tasks or tests measures these domains in English language. However, there are currently no French‐language tools for evaluating and monitoring the early literacy abilities of young children in francophone contexts.

Methods

This paper addresses this lack by presenting a new French‐language scale – the Echelle Préscolaire de Littératie Emergente (EPLE) – for assessing the early literacy skills of preschoolers. In addition to examining the EPLE's psychometric properties, we used path analysis to determine possible links between different dimensions of early literacy and children's characteristics (sex, age and socioeconomic status).

Results

This study involves 167 French preschoolers (mean = 5.17 years, standard deviation = 0.59) attending kindergarten. All the participants were tested individually, and a specific entry in the tasks was proposed depending on the age of the children. First, the EPLE had good psychometric properties. Then, factor analysis of the data collected revealed a similar hierarchical factor structure as found in the literature. In addition, we found links between the four dimensions of early literacy measured by the EPLE and both children's age and socioeconomic status.

Conclusion

The EPLE creates several new opportunities for early literacy research in French‐speaking contexts. First, this tool reduces the gap in the field of testing young children skills. Then, it allows the comparison with worldwide researches. Moreover, this tool proposes pedagogical implications. In the next few years, the EPLE will be used by teachers or school psychologists to test the early competences of French children.
The impact of autoimmune systemic inflammation and associated medications on male reproductive health in patients with chronic rheumatological, dermatological, and gastroenterological diseases: A systematic review
Authors: Finelli Renata , Leisegang Kristian , Finocchi Federica , De Masi Salvatore , Agarwal Ashok , Damiani Giovanni
Published: January 2021

Autoimmune disorders currently affect 5%‐8% of the global population, characterized by an aberrant chronic inflammatory response to self‐antigens. The aim of this study was to systematically review the current available evidence investigating the impact of systemic autoimmune diseases and associated immunosuppressive treatment on fertility parameters of adult men. Clinical trials, observational studies, and case reports written in English and reporting semen analysis, evaluation of seminal oxidative stress, and/or sperm DNA fragmentation in patients affected by psoriasis and psoriatic arthritis, celiac disease, inflammatory bowel diseases, systemic lupus erythematosus, ankylosing spondylitis, hidradenitis suppurativa, uveitis, dermatomyositis, and rheumatoid arthritis were collected by searching on PubMed, EMBASE, OVID, Scopus, and Cochrane Library databases, with no limit of time. The study quality and the extent of bias in design, methods, and outcome assessment were evaluated by applying the Joanna Briggs Institute Critical Appraisal tools. Evidence suggested that various autoimmune diseases or relevant medications can adversely affect male fertility parameters and that patients may benefit of counseling and sperm cryopreservation. Clinical trials further investigating any adverse effect of autoimmunity and related thereby on male infertility are warranted, to develop appropriate guidelines for males diagnosed and treated for autoimmune disorders.
Legitimacy crises and the temporal dynamics of bureaucratic representation
Authors: Murdoch Zuzana , Connolly Sara , Kassim Hussein , Geys Benny
Published: January 2021

The representation of specific groups and social interests within (or by) the civil service has long been a concern of public administration scholarship. Yet, much of this literature focuses on representation at a single point in time. In this article, we propose a more dynamic perspective. In terms of theory, we postulate specific temporal relationships between triggering cues (e.g., a crisis event) and the representation decisions of civil servants. We specify two complementary mechanisms underlying these relationships: that is, a sensemaking process whereby the perceived meaning and relative salience of distinct groups and interests changes over time; and a shift in bureaucrats' discretion to represent specific groups or interests changes over time. We illustrate these time‐dependent processes using interview and survey data from the European Commission.
Improved Reliability of Automated ASPECTS Evaluation Using Iterative Model Reconstruction from Head CT Scans
Authors: Löffler Maximilian T. , Sollmann Nico , Mönch Sebastian , Friedrich Benjamin , Zimmer Claus , Baum Thomas , Maegerlein Christian , Kirschke Jan S.
Published: January 2021

BACKGROUND AND PURPOSE

Iterative model reconstruction (IMR) has shown to improve computed tomography (CT) image quality compared to hybrid iterative reconstruction (HIR). Alberta Stroke Program Early CT Score (ASPECTS) assessment in early stroke is particularly dependent on high‐image quality. Purpose of this study was to investigate the reliability of ASPECTS assessed by humans and software based on HIR and IMR, respectively.

METHODS

Forty‐seven consecutive patients with acute anterior circulation large vessel occlusions (LVOs) and successful endovascular thrombectomy were included. ASPECTS was assessed by three neuroradiologists (one attending, two residents) and by automated software in noncontrast axial CT with HIR (iDose4; 5 mm) and IMR (5 and 0.9 mm). Two expert neuroradiologists determined consensus ASPECTS reading using all available image data including MRI. Agreement between four raters (three humans, one software) and consensus were compared using square‐weighted kappa (κ).

RESULTS

Human raters achieved moderate to almost perfect agreement (κ = .557‐.845) with consensus reading. The attending showed almost perfect agreement for 5 mm HIR (κHIR = .845), while residents had mostly substantial agreements without clear trends across reconstructions. Software had substantial to almost perfect agreement with consensus, increasing with IMR 5 and 0.9 mm slice thickness (κHIR = .751, κIMR = .777, and κIMR0.9 = .814). Agreements inversely declined for these reconstructions for the attending (κHIR = .845, κIMR = .763, and κIMR0.9 = .681).

CONCLUSIONS

Human and software rating showed good reliability of ASPECTS across different CT reconstructions. Human raters performed best with the reconstruction algorithms they had most experience with (HIR for the attending). Automated software benefits from higher resolution with better contrasts in IMR with 0.9 mm slice thickness.
Cerebrospinal fluid flow on time‐spatial labeling inversion pulse images before and after treatment of congenital hydrocephalus in a dog
Authors: Ito Daisuke , Ishikawa Chieko , Jeffery Nick D. , Kitagawa Masato
Published: January 2021

A 3‐month‐old male cross‐breed dog presented with signs of progressive diffuse brain disease. Noncommunicating congenital hydrocephalus concurrent with cervical syringomyelia was diagnosed on magnetic resonance images. On time‐spatial labeling inversion pulse (Time‐SLIP) images CSF flow through the mesencephalic aqueduct was poorly defined and there was flow into the syrinx across the craniocervical junction. After percutaneous ventricular drainage and ventriculoperitoneal shunting, CSF flow through the aqueduct was clearly detected and flow into the syrinx disappeared. In addition, CSF flow in the subarachnoid space at the pons and ventral aspect of the cervical subarachnoid space was restored. Signs of neurological dysfunction improved after ventriculoperitoneal shunting and the cerebral parenchyma was increased in thickness on 2‐year follow‐up computed tomography images. Patterns of CSF flow on Time‐SLIP images before and after CSF drainage or ventriculoperitoneal shunting aid in clarifying disease pathogenesis and confirm effects of CSF drainage.
Assessing knowledge, attitudes, and practices of Canadian veterinarians with regard to Lyme disease in dogs
Authors: Nichol Grace K. , Weese J. Scott , Evason Michelle , Clow Katie M.
Published: January 2021

Background

The blacklegged tick (BLT) is a vector for the bacteriumBorrelia burgdorferi(Bb), which causes Lyme disease. Range expansion of the BLT in Canada is related to an increased risk of Lyme disease in many regions. Current literature, such as the 2018 American College of Veterinary Internal Medicine consensus statement, suggests that there may be differences in the approaches of veterinarians who encounter dogs exposed to Bb and dogs with Lyme disease.

Objectives

To determine current knowledge, attitudes, and practices of Canadian veterinarians regarding Lyme disease in dogs.

Animals

None.

Methods

An online survey was distributed to Canadian veterinarians through veterinary associations and industries. Survey responses were analyzed using descriptive statistics, spatial analysis, Fisher's exact tests, and univariable logistic regression.

Results

At the completion of the survey, 192 responses were received from veterinarians practicing in all 10 Canadian provinces. Answers to short scenario and treatment questions reflected a wide variety of clinical approaches taken by veterinarians. Regional differences were seen in reported tick distribution and clinical approaches.

Conclusions and Clinical Importance

Regional differences and generalized differences were found in approaches used by responding Canadian veterinarians with regard to managing Bb exposure and Lyme disease in dogs. We identified areas for future research and knowledge mobilization for veterinarians.
Jim Crow and John Bull in London: Transatlantic Encounters with Race and Nation in the Second World War
Authors: Ayers Oliver
Published: January 2021

The arrival of a segregated American army on British shores during the Second World War forced the UK government and the public to confront questions of race and nation in new ways. This article places London, the imperial metropolis, in a central role in this wartime drama by deploying evidence compiled as part of the Mapping Black London in World War II digital history project. The article reveals a hitherto under‐acknowledged range and scale of African American activity in the capital, with a cast of characters including newspaper correspondents, musicians, social workers, nurses, political activists and, of course, many thousands of service personnel – both men and women. For an African American public back home, these metropolitan activities were viewed both as part of the international war effort and also from the perspective of a domestic American scene affected by rural to urban migration and an upsurge in racial protest and tension. The result was a short, sharp but transformative transatlantic encounter that highlights the connections between historical trajectories often considered in separate terms: the US civil rights movement, British domestic race relations, and the international forces – not least the decline of European empire fomented by war – that bound them together.
Use of convalescent plasma for managing severe COVID‐19 infection in 2‐month‐old infant
Authors: Shukla Umesh , Bhakhri Bhanu , Arora Satyam , Jain Mukul , Jain Vikas , Dua Seema , Singh Dharmendra Kumar , Gupta Devendra Kumar
Published: January 2021

A 58‐day‐old female infant reported with complaints of fever, difficult breathing, loose stool, vomiting and refusal to feed for 4 days. Laboratory work showed anaemia, leucocytosis with elevated neutrophils and thrombocytopenia along with high C‐reactive protein and D‐dimer with bilateral patchy infiltrate on X‐ray and positivity for COVID‐19. Her blood culture was also positive for Gram‐negative bacilli (acinetobacter lwoffii). Along with antibiotics, she was given 50 ml convalescent plasma. She was off oxygen within 2 days and showed improvement in lung lesions, and RT‐PCR was negative by day 7 and discharged by day 10 of transfusion.
Performance and Losses Analysis for Radial Turbine Featuring a Multi-Channel Casing Design
Authors: Hassan Ahmed Farid Ayad , Schatz Markus , Vogt Damian M.
Published: January 2021

A novel control technique for radial turbines is under investigation for providing turbine performance controllability, especially in turbocharger applications. This technique is based on replacing the traditional spiral casing with a multi-channel casing (MC). The MC divides the turbine rotor inlet circumferentially into a certain number of channels. Opening and closing these channels controls the inlet area and, consequently, the turbine performance. The MC can be distinguished from other available control techniques in that it contains no movable parts or complicated control mechanisms. Within the casing, this difference makes it practical for a broader range of applications. In this investigation, a turbocharger featuring a turbine with MC has been tested on a hot gas test stand. The experimental test results show a reduction in the turbine operating efficiency when switching from full to partial admission. This reduction increases when reducing the admission percentage. To ensure the best performance of the turbine featuring MC while operating at different admission configurations, it becomes crucial to investigate its internal flow field at both full and partial admission to understand the reasons for this performance reduction. A full 3D computational fluid dynamics (CFD) model of the turbine was created for this investigation. It focuses on identifying the loss mechanisms associated with partial admission. Steady and unsteady simulations were performed and validated with available test data. The simulation results show that operating the turbine at partial admission results in highly disturbed flow. It also detects the places where aerodynamic losses occur and which are responsible for this performance reduction. This operation also shows flow unsteadiness even when operating at steady conditions. This unsteadiness depends mainly on the admission configuration and percentage.
Averaging for High Fidelity Modeling—Toward Large Eddy Simulations in Multi-Passage Multi-Row Configurations
Authors: He L.
Published: January 2021

A major challenge in high-fidelity turbomachinery flow computations is the need for high resolution in a very large domain of multiple blade-passages and multiple blade rows. Scale-resolving turbulent solutions are prohibitively costly. The question is, what will it take to get high-fidelity solutions if we are only after time-mean flows for aerothermal performance?

A novel two-scale approach is adopted to address the issue by coupling between a local fine-mesh domain in a single-passage and a global coarse-mesh multi-passage domain. This is achieved by harnessing the extra product terms generated when averaging a nonlinear process in time, as well as in space. As such a space-time averaging is purposely applied in either a direct mode or an inverse one in the two domains respectively. The source terms in a compact form (one scalar for one equation) are conveniently obtained to enable the interaction between the single-passage fine-mesh and the multi-passage coarse-mesh solutions. The converged solution for this two-scale coupled system should meet two seemingly conflicting requirements: an otherwise poorly conditioned local fine-mesh domain is now subject to a right environment/flow conditions, and an otherwise poorly resolved global coarse-mesh domain is now effectively subject to high resolution. In this paper, the concepts, the formulations of the framework methodology, and the implementation methods will be described. The validity and feasibility of the approach for efficient scale-resolving high- fidelity turbomachinery flow simulations will be illustrated by several computational examples of practical interest.
The Difficulties of Predicting the Coefficient of Friction in Cold Flat Rolling
Authors: Szűcs Máté , Krallics György , Lenard John G.
Published: January 2021

The flat rolling process is initiated when the frictional forces draw the strip to be rolled into the roll gap. These forces depend on the coefficient of friction, knowledge of which is essential to understand, describe, and analyze the process. Several predictive formulae for the coefficient have been presented in the technical literature. Contradictions are observed, however, when their predictions are compared to each other. The data obtained while cold rolling aluminum and steel strips are used in the analyses. A model of the rolling process—accounting for strain hardening, frictional events, and varying speeds—is then used to determine the coefficients of friction. The use of statistical analyses is found to yield more reliable results than the use of the predictive relations.
Energy Efficiency of Drying Kinetics Process of Hydroxide Sludge Wastes in an Indirect Convection Solar Dryer
Authors: Fantasse Azeddine , Lakhal El Khadir , Idlimam Ali , Berroug Fatiha
Published: January 2021

The treatment of sludge, which is produced from raw water treatment, has been considered as an ecologically sensitive problem in terms of energy and pollution. In this context, this study presents many series of solar drying tests that were carried on three samples of sludge obtained from several drinking water treatment plants in Marrakech-Safi regions, Morocco. The main aim is to develop further management processes of these wastes such as upgrading or storage. A partially solar indirect convective dryer operating in forced convection was used to run experiment tests. The temperature of air has ranged from 50 to 90°C and the relative humidity from 24% to 46%. The drying airflow was kept at about 0.0833 m3/s. An estimation of the mass diffusion coefficient and the activation energy during vacuum drying besides the characteristic convective drying curve were established. In addition, six semi-theoretical and/or empirical and statistical models were used to predict experimental data. It was found that the temperature was the most important factor during the drying process. Furthermore, the obtained results of mass diffusion coefficient and activation energy were found consistent with those already existing in the literature. The mathematical model called “Midilli–Kucuk” was found to be the most appropriate to describe the drying curves of the three samples. The total energy consumption was also studied. It showed a downward tendency with the increase in temperature. The efficiency of drying energy ranged from 4.89% to 7.5%. Although it was found to be low, it can be improved by increasing the load.
Design of a Single-Phase Switched Boost Inverter With Important Potential of Conversion in Variable Conditions
Authors: Amari Yehya , Hasni Mourad , Labdai Sami , Mellit Adel
Published: January 2021

In this paper, a single-phase switched boost inverter is proposed. Dividing converted sources is a very popular technique in recent years, as well as the demand for high output voltage quality by the use of a small number of switches. The analysis and simulation study revealed that this inverter has a good potential in terms of conversion quality (high voltage gain, low total harmonic distortion (THD), low cost, simple structure, and easy to control) and can be used in photovoltaic applications as well as in embedded systems. Experimental results verify the functioning principle of the presented topology but this new topology needs more improvements to reach exactly the simulation results.
Recovery of Partial Heat of Pyrolysis From Solar Thermal Collector for Thermochemical Conversion of Food Waste
Authors: Ogedengbe E. O. B. , Odeleye J. O. , Enarevba D. R. , Ehinmowo A. B. , Awosanya O. G.
Published: January 2021

Biomass conversion processes can be energy intensive. There is a need to seek renewable sources to meet such energy demand. In this study, a partial heat of pyrolysis from a concentrated solar power (CSP)-based solar heat collector is modeled. A numerical investigation of the flow in the heat collector element (HCE) of the CSP is performed. By using the finite volume formulation, the fluid flow behavior within the pipe of the HCE is simulated to determine the thermal absorption, heat losses, and efficiency obtainable from the solar irradiation on the receiver tube. Monte-Carlo Ray-tracing based software, soltrace, is used to estimate the incident heat flux on the LS-2 receiver with an average direct normal irradiance (DNI) value, based on a comparative performance study of three types of molten salts (i.e., the heat transfer fluids (HTFs)). The performance of three kinds of the LS-2 HCE (i.e., vacuum, air-filled, and evacuated types) is also analyzed in terms of heat loss and efficiency measurements respectively. HITEC provides the best performance in terms of stability in delivering the partial heat of pyrolysis for the gasification of food waste on moderate velocities of 0.75—2 m/s. Also, the pyrolysis of the feedstock is proposed with an operating feedstock rate of 0.19 kg/s and 0.17 kg/s for lower heating value (LHV) and higher heating value (HHV), respectively. It is anticipated that the combined heat of pyrolysis from the proposed dual heat cycle, comprising both the CSP and a biogas plant, will provide a solution to the demand for alternative power from biomass energy conversion.
Multidimensional Data Modeling and Model Validation for Digital Twin Workshop
Authors: Qian Weiwei , Guo Yu , Cui Kai , Wu Pengxing , Fang Weiguang , Liu Daoyuan
Published: January 2021

Digital twin workshop (DTW) is an important embodiment of intelligent manufacturing in the workshop level, which enables the smart production control and management of the workshop. However, there still exist problems including data modeling and verification of digital model in the process of DTW construction. To solve these problem, multidimensional data modeling and model validation methods of DTW are proposed in this article. First, five-order tensor models for representing manufacturing elements are established to unify the data from physical workshop (PW) and virtual workshop (VW). Then, the mathematical method for verifying DTW twin model is proposed from the recessive and explicit perspective. Finally, a case study of an aerospace machining workshop is carried out to verify the operability and effectiveness of the proposed method. The case analysis shows that the proposed methods can effectively evaluate whether the twin model accurately provides the description of the actual behavior process of physical workshop, and the proposed methods have good performance.
A Method for Pump Manifold Performance Calculations in Hydraulic Air Compressors
Authors: Millar Dean , Pourmahdavi Maryam
Published: January 2021

Analytical methods are described that were developed to undertake the pump manifold calculations for hydraulic air compressors (HACs) where multiple pumps are installed in parallel configurations. The procedures are fast and exact and were developed for design optimization and control tasks which, although described in the specific context of HACs, are also applicable to more general pumping systems. The proposed method uses a recursive/iterative procedure to establish the pump curve equivalent to the pump combination so that the design performance of the system can be assessed for any value of externally attached hydraulic resistance. The technique is verified against a numerical method applied to the same problem, but where the external hydraulic resistance must be completely specified for a solution. Losses at convergent and divergent wyes, which are required to create the parallel pump manifold arrangements, are found to be significant factors in establishing the overall energy efficiency of the pumping system. With efficient pump manifold arrangements designed, a so-called binary pumping scheme is explained, where individual pumps in the manifold can be activated (1) or deactivated (0) so that the pumping system flow can be reduced with good turn-down ratios while ensuring that the best efficiency point (BEP) efficiency of the system is maintained (exemplified with 4:1 or 25%).
Numerical Calibration of Three-Dimensional Printed Five-Hole Probes for the Transonic Flow Regime
Authors: Passmann Maximilian , aus der Wiesche Stefan , Joos Franz
Published: January 2021

This paper presents a method for a cost- and time-effective calibration procedure for five-hole probes for the transonic flow regime based on additive manufacturing and a numerical calibration routine. The computational setup and calibration routine are described in detail. The calibration procedure is tested on a custom-built L-shaped conical probe of 30 deg half-angle with a flat tip and an outer diameter of 2.4 mm. The probe tip is manufactured in stainless steel using direct metal laser sintering. Numerical calibration is carried out over a Mach number range of 0.2–1.4 and pitch and yaw angles of ±45 deg. The numerical calibration charts are validated with wind tunnel tests across the entire Mach number range and the expected accuracy of the numerical calibration method is quantified. Exemplary results of area traverses up- and downstream of a linear transonic turbine cascade with tip clearance are presented and discussed briefly.
Forecasting and Detection of Fatigue Cracks in Polycrystalline Alloys With Ultrasonic Testing Via Discrete Wavelet Transform
Authors: Alqahtani Hassan , Ray Asok
Published: January 2021

Forecasting and detection of fatigue cracks play a key role in damage mitigation of mechanical structures (e.g., those made of polycrystalline alloys) to enhance their service life, and ultrasonic testing (UT) has emerged as a powerful tool for detection of fatigue cracks at early stages of damage evolution. Along this line, the work reported in this paper aims to improve the performance of fatigue crack forecasting and detection based on a synergistic combination of discrete wavelet transform (DWT) and Hilbert transform (HT) of UT data, collected from a computer-instrumented and computer-controlled fatigue-testing apparatus. Performance of the proposed method is evaluated by comparison with the images generated from a digital microscope, which are treated as the ground truth in this paper. The results of comparison reveal that forthcoming fatigue cracks can be detected ahead of their appearance on the surface of test specimens. The proposed method apparently outperforms both HT and conventional DWT, when they are applied individually, because the synergistic combination of DWT and HT provides a better characterization of UT signal attenuation for detection of fatigue crack damage.
Energy, Exergy, Environmental (3E) and Parametric Assessment of a Triple-Pressure Reheat Combined-Cycle Power Plant
Authors: Jamnani Mohammadreza Babaei , Ting David S-K , Carriveau Rupp , Kardgar Amin
Published: January 2021

In this study, energy, exergy, and environmental (3E) assessments have been conducted on a proposed combined-cycle power plant (CCPP) with three pressure levels of the HRSG and reheating process. 3E design approaches cross-link mechano-electric and environmental objectives. Herewith, the suggested combined-cycle is formed by a gas unit, condenser, steam turbines, triple-pressure heat recovery steam generator (HRSG) and also utilizes reheat facilities and auxiliary components. It is observed that more than 56% of total exergy destruction occurs in the combustor, followed by HRSG (15.29%), steam turbines (roughly 15.02%), gas turbine (8.93%), air compressor (1.79%), and condenser (0.66%). A parametric study is also presented that examines the sensitivity of performance indicators to various environmental states, steam pressures, pinch points, and steam mass flow rates. Moreover, it is presented that the implementation of Siemens SGT-100-1S over other GT configurations can considerably reduce deficiency of the overall cycle. The effects of each contaminant mass flowrate (NOx, CO, UHC, and CO2) and adiabatic flame temperature (AFT) are also studied when the gas unit operates under partial power and incomplete combustion conditions. In conclusion, a number of potential causes of irreversibilities and corrective optimization guidance are offered for each main equipment of the CCPP.
Numerical Investigation of Turbulent Offset Jet Flow Over a Moving Flat Plate Using Low-Reynolds Number Turbulence Model
Authors: Behera Vishwa Mohan , Rathore Sushil Kumar
Published: January 2021

The present study reports the numerical simulation of turbulent plane offset jet flow over a moving plate. The effect of plate velocity on various flow characteristics is discussed in detail including the special case of a stationary plate. For turbulence closure, the low-Reynolds number (LRN) turbulence model proposed by Yang and Shih (YS) is applied because it is computationally robust and reported to work quite effectively in several complex flow situations. The computations have been carried out with a Reynolds number of 15,000 for various offset ratios (OR = 3, 7, and 11) and different velocity ratios (Uplate) of the plate in the range 0–2. The finite volume method (FVM) with a staggered grid arrangement has been used to solve the transport equations. The application of the LRN model along with the integration to wall (ITW) approach enables us to capture one closed loop of the Moffatt vortex near the left corner of the wall for the stationary plate case. The spreading of the jet has been found to reduce by increasing the velocity of the plate. The jet half-width lies very close to the wall for the plate to jet velocity 1.5 and 2. For two extreme limits of plate velocity, i.e., Uplate = 0 and 2, the nearly self-similar profiles are observed at different axial locations in the wall jet region. Also, the flow is observed to exhibit nearly self-similar behavior when velocity profiles are plotted for various offset ratios at a given axial location in the wall jet region for Uplate = 0 and 2. It has been found that the flow characteristics are significantly influenced by the plate velocity.
Site dependence of ultrasonically induced electrical potentials in bone
Authors: Nakamura Tsukasa , Takata Mineaki , Michimoto Itsuki , Koyama Daisuke , Matsukawa Mami
Published: January 2021

The success rate of low-intensity pulsed ultrasound (LIPUS) therapy depends on the bone site. However, the initial mechanism of physical stimulation by ultrasound and bone cellular response remains unclear. One possible physical stimulation is the induced electrical potentials due to the piezoelectricity. In this study, the output electrical potentials of ultrasound transducers made from bovine bones were investigated. Transducers made from the radius bone showed the largest electric potentials, followed by tibia, femur, and humerus. There was clear site dependence of the induced electric potentials of bone, in good accordance with the success rate of LIPUS therapy.
Widespread haploid-biased gene expression enables sperm-level natural selection
Authors: Bhutani Kunal , Stansifer Katherine , Ticau Simina , Bojic Lazar , Villani Alexandra-Chloé , Slisz Joanna , Cremers Claudia M. , Roy Christian , Donovan Jerry , Fiske Brian , Friedman Robin C.
Published: January 2021

Sperm-specific natural selection

Sperm cells are genetically haploid, but because of the cytoplasmic bridges that link cells, they can be transcriptionally diploid. However, some gene transcripts are not shared. Bhutani
et al.
sequenced single sperm from mice, cattle, and macaques to determine the extent of distortion in the expression of these putatively selfish transcripts, which the authors call genoinformative markers (GIMs). Investigating the evolutionary pressures on these GIMs, they found that they exhibited signatures of positive selection yet tend to be biased toward sperm function. This observation explains why, relative to other tissues, testis shows distinctive gene expression patterns.

Science
, this issue p.
eabb1723
Public debate is good for science
Authors: Thorp H. Holden
Published: January 2021

In the age of the internet, there's no such thing as a private debate. But is that bad for science? Some scientists have had misgivings. When debates in any sector move beyond the halls of universities and government agencies, there is potential for misuse of information and public confusion. But open debate can also foster communication among scientists and between the scientific community and the public. During the pandemic, open debate on research, health, and policy—whether on television, in newspapers, or on social media—widened public attention and encouraged more diverse voices. If this trend spurs scientists to agree more quickly about the best solutions to our problems—and at the same time helps the public “see” the process of scientific discourse more clearly—then this is good for everyone, including scientists.
Nonsteroidal Anti-inflammatory Drugs Dampen the Cytokine and Antibody Response to SARS-CoV-2 Infection
Authors: Chen Jennifer S. , Alfajaro Mia Madel , Chow Ryan D. , Wei Jin , Filler Renata B. , Eisenbarth Stephanie C. , Wilen Craig B.
Published: January 2021

Public health officials have raised concerns about the use of nonsteroidal anti-inflammatory drugs (NSAIDs) for treating symptoms of coronavirus disease 2019 (COVID-19). NSAIDs inhibit the enzymes cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2), which are critical for the generation of prostaglandins—lipid molecules with diverse roles in homeostasis and inflammation.
Adeno-associated Virus (AAV) Capsid Chimeras with Enhanced Infectivity Reveal a Core Element in the AAV Genome Critical for both Cell Transduction and Capsid Assembly
Authors: Viney Lydia , Bürckstümmer Tilmann , Eddington Courtnee , Mietzsch Mario , Choudhry Modassir , Henley Tom , Agbandje-McKenna Mavis
Published: January 2021

A major hurdle to the therapeutic potential of AAV in gene therapy lies in achieving clinically meaningful AAV doses, and secondarily, the ability to manufacture commercially viable titers of AAV to support this. By virtue of neutralizing antibodies against AAV that impede patient repeat dosing, the dose of AAV for
in vivo
gene delivery has been high, which has resulted in unfortunate recent safety concerns and deaths in patients given higher-dose AAV gene therapy.
A Potent Anti-Simian Immunodeficiency Virus Neutralizing Antibody Induction Associated with a Germ Line Immunoglobulin Gene Polymorphism in Rhesus Macaques
Authors: Matsuoka Saori , Kuwata Takeo , Ishii Hiroshi , Sekizuka Tsuyoshi , Kuroda Makoto , Sano Masato , Okazaki Midori , Yamamoto Hiroyuki , Shimizu Mikiko , Matsushita Shuzo , Seki Yohei , Saito Akatsuki , Sakawaki Hiromi , Hirsch Vanessa M. , Miura Tomoyuki , Akari Hirofumi , Matano Tetsuro
Published: January 2021

Vaccines against a wide variety of infectious diseases have been developed mostly to induce antibodies targeting pathogens. However, a small but significant percentage of people fail to mount potent antibody responses after vaccination, while the underlying mechanism of host failure in antibody induction remains largely unclear.
“Missing links” for the long-lived Macdonald and Arago hotspots, South Pacific Ocean
Authors: Buff L. , Jackson M.G. , Konrad K. , Konter J.G. , Bizimis M. , Price A. , Rose-Koga E.F. , Blusztajn J. , Koppers A.A.P. , Herrera Santiago
Published: January 2021

The Cook-Austral volcanic lineament extends from Macdonald Seamount (east) to Aitutaki Island (west) in the South Pacific Ocean and consists of hotspot-related volcanic islands, seamounts, and atolls. The Cook-Austral volcanic lineament has been characterized as multiple overlapping, age-progressive hotspot tracks generated by at least two mantle plumes, including the Arago and Macdonald plumes, which have fed volcano construction for ∼20 m.y. The Arago and Macdonald hotspot tracks are argued to have been active for at least 70 m.y. and to extend northwest of the Cook-Austral volcanic lineament into the Cretaceous-aged Tuvalu-Gilbert and Tokelau Island chains, respectively. Large gaps in sampling exist along the predicted hotspot tracks, complicating efforts seeking to show that the Arago and Macdonald hotspots have been continuous, long-lived sources of hotspot volcanism back into the Cretaceous. We present new major- and trace-element concentrations and radiogenic isotopes for three seamounts (Moki, Malulu, Dino) and one atoll (Rose), and new clinopyroxene 40Ar/39Ar ages for Rose (24.81 ± 1.02 Ma) and Moki (44.53 ± 10.05 Ma). All volcanoes are located in the poorly sampled region between the younger Cook-Austral and the older, Cretaceous portions of the Arago and Macdonald hotspot tracks. Absolute plate motion modeling indicates that the Rose and Moki volcanoes lie on or near the reconstructed traces of the Arago and Macdonald hotspots, respectively, and the 40Ar/39Ar ages for Rose and Moki align with the predicted age progression for the Arago (Rose) and Macdonald (Moki) hotspots, thereby linking the younger Cook-Austral and older Cretaceous portions of the long-lived (>70 m.y.) Arago and Macdonald hotspot tracks.
Canonical analysis of geometrical action for Dp-brane
Authors: Klusoň Josef
Published: January 2021

In this short note we perform canonical analysis of geometrical action for Dp-brane. We also discuss tachyon condensation in case of the geometrical action for unstable D(p+1)-brane.
Implementation of the CMS-EXO-19-002 search in the MadAnalysis 5 framework (physics beyond the Standard Model with multilepton final states; 137 fb−1)
Authors: Conte Eric , Ducrocq Robin
Published: January 2021

In this paper, we present the MadAnalysis 5 implementation of the CMS-EXO-19-002 analysis, probing an excess of events featuring multiple charged leptons in LHC proton–proton collisions at [Formula: see text]. The original analysis is based on data acquired by the CMS detector during the 2016–2018 campaign, which corresponds to an integrated luminosity of 137 fb[Formula: see text]. Data have been tested against hypothetical extensions of the Standard Model where additional leptons can stem from new heavy fermion decays or from new light scalar/pseudoscalar decays. The CMS selection has been fully implemented in the MadAnalysis 5 platform and successfully validated by reproducing official results in the form of signal distributions at the end of the selection.
Review of the Third Summer School on the Practice and Theory of Distributed Computing SPTDC 2020
Authors: Aksenov Vitaly , Kuznetsov Petr
Published: January 2021

The third edition of the Summer School on Practice and Theory of Distributed Computing (SPTDC 2020) took place on July 6-9, 2020. Because of the ongoing pandemic, the school was held in a virtual format. Following the strategy of the rst and the second editions, we invited prominent researchers working on distributed systems to give lectures on their favourite topics and hold virtual discussions with the students. This year the school pursued three major themes: persistent computing, large-scale replicated systems and cryptographic tools in distributed systems. The program featured classes from Alexey Gotsman, Michael Scott, Christian Cachin, Prasad Jayanti, Idit Keidar, Rodrigo Rodrigues and Jing Chen. We had a record number of 150 registered participants: undergraduate and graduate students, as well as industrial researchers and software engineers from all around the globe.
Chitosan and Derivatives: Bioactivities and Application in Foods
Authors: Zhou Da-Yong , Wu Zi-Xuan , Yin Fa-Wen , Song Shuang , Li Ao , Zhu Bei-Wei , Yu Liang-Li (Lucy)
Published: January 2021

Chitosan is a biodegradable, biocompatible, and nontoxic aminopolysaccharide. This review summarizes and discusses the structural modifications, including substitution, grafting copolymerization, cross-linking, and hydrolysis, utilized to improve the physicochemical properties and enhance the bioactivity and functionality of chitosan and related materials. This manuscript also reviews the current progress and potential of chitosan and its derivatives in body-weight management and antihyperlipidemic, antihyperglycemic, antihypertensive, antimicrobial antioxidant, anti-inflammatory, and immunostimulatory activities as well as their ability to interact with gut microbiota. In addition, the potential of chitosan and its derivatives as functional ingredients in food systems, such as film and coating materials, and delivery systems is discussed. This manuscript aims to provide up-to-date information to stimulate future discussion and research to promote the value-added utilization of chitosan in improving the safety, quality, nutritional value and health benefits, and sustainability of our food system while reducing the environmental hazards.