bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on the Influencing Factors of the Atomization Rate in a Piezoceramic Vibrating Mesh Atomizer
Authors: Yan Qiufeng , Sun Wanting , Zhang Jianhui
Published: April 2020

On the basis of previous study in our research group, the phenomenon of the dynamic tapered angle was founded, the occurrence of atomization is regarded to derive from the combined effects of the dynamic variation of the micro-tapered aperture, and the difference between forward and reverse flow resistance has been explained by both theories and experiments. It has been revealed that the main influencing factors of the atomization rate are driving voltage, driving frequency, and so on, while the root causes of the various atomization rates still need to be further clarified. In this paper, a micro-tapered aperture worked as a micron-sized tapered flow tube valveless piezoelectric pump in periodic variation. The working principle of such a micro-tapered aperture atomizer was analyzed in detail, and the corresponding formula of the atomization rate was also established. Through measuring the atomization rates at different working frequencies (f), it was established that when the f was set as 122 kHz, the atomization rate reached a maximum value. By building the relationship between the atomization rate and voltage at a fixed resonance frequency, it can be seen that the atomization rate increased with the increase of driving voltage. Subsequently, in order to measure their atomization rates, the micro-tapered apertures of three different outlet diameters were applied, so that the atomization rate was enhanced with the increase of the micro-tapered aperture diameter. Moreover, through examining the atomization rates at different temperatures, it was observed that the atomization rate rose with increasing temperature; while changing the liquid concentration, the atomization rate was also enhanced by the increase in its concentration. Apparently, the impact factors including working frequency, driving voltage, outlet diameter, temperature, and liquid concentration all exert some effects on the atomization rate. It is worth noting that at the first stage, these influence factors indirectly work on the micro-tapered aperture structure or flow state, followed by further effects on the flow resistance. As above-mentioned, in this work, we considered that the root cause influencing the atomization rate in a piezoceramic vibrating mesh atomizer can be attributed to the flow resistance.
Non-Uniform Temperature Field of Spatial Grid Structure under Construction Induced by Solar Radiation
Authors: Chen Deshen , Qian Hongliang , Wang Huajie , Xu Wucheng , Li Jingfang
Published: April 2020

The temperature of spatial structures under construction can have a significant non-uniform distribution induced by intense solar radiation. This temperature distribution affects the component assembly and results in closure difficulties, potentially causing safety hazards. A spatial grid structure model was designed and subjected to temperature field test under sunlight to study the temperature distribution of the structure and for comparison with numerical simulation methods. The distribution characteristics and the time-varying laws were analyzed based on the test data. Then, the ray-casting algorithm was introduced to analyze the shadow influence between members, so that the temperature distribution of the model was simulated accurately, which was verified by the test data. The results show that the spatial grid structure had an obvious non-uniform temperature distribution, with a maximum temperature rise of 16 °C when compared with ambient temperature and a maximum temperature difference between members of 11 °C. The variation laws were gained both from the test and the numerical simulation. The numerical simulation method proposed herein can be used to calculate the shadow distribution and the temperature field of the structure effectively. The research methods and conclusions can provide valuable references for thermal design, monitoring, and control of spatial grid structures.
Dietary Supplementation with Pioglitazone Hydrochloride and Resveratrol Improves Meat Quality and Antioxidant Capacity of Broiler Chickens
Authors: Zhang Fan , Jin Chenglong , Jiang Shiguang , Wang Xiuqi , Yan Huichao , Tan Huize , Gao Chunqi
Published: April 2020

The study aimed to investigate the effects of pioglitazone hydrochloride (PGZ) and resveratrol (RES) on yellow-feathered broiler chickens. A total of 500 broiler chickens were randomly divided into four groups and fed a basic diet (control group) or a basic diet supplemented with 15 mg/kg PGZ, 400 mg/kg RES, or 15 mg/kg PGZ plus 400 mg/kg RES for 28 days. Compared with the control group, the PGZ and PGZ plus RES groups presented a significantly higher average daily gain and a decreased feed-to-gain ratio. Increases in the dressing percentage, semi-eviscerated yield, muscle intramuscular fat content, and C18:1n-9c, C18:3n-6, C20:3n-3, and monounsaturated fatty acid (MUFA) percentages were found in the PGZ plus RES group. Moreover, the diet supplemented with RES or PGZ plus RES increased the activities of catalase, glutathione peroxidase, and superoxide dismutase, and decreased the levels of reactive oxygen species of thigh muscle. Additionally, the mRNA abundance of peroxisome proliferator-activated receptor γ coactivator 1α, fatty acid-binding protein 3, nuclear factor erythroid-2-related factor 2, and superoxide dismutase 1 was increased in the PGZ plus RES group. In conclusion, this study suggested that dietary supplementation of PGZ combined with RES improved the growth performance, the muscle intramuscular fat content, and antioxidant ability of yellow-feathered broiler chickens.
Execution Model to Reduce the Interference of Shared Memory in ARINC 653 Compliant Multicore RTOS
Authors: Park Sihyeong , Kwon Mi-Young , Kim Hoon-Kyu , Kim Hyungshin
Published: April 2020

Multicore architecture is applied to contemporary avionics systems to deal with complex tasks. However, multicore architectures can cause interference by contention because the cores share hardware resources. This interference reduces the predictable execution time of safety-critical systems, such as avionics systems. To reduce this interference, methods of separating hardware resources or limiting capacity by core have been proposed. Existing studies have modified kernels to control hardware resources. Additionally, an execution model has been proposed that can reduce interference by adjusting the execution order of tasks without software modification. Avionics systems require several rigorous software verification procedures. Therefore, modifying existing software can be costly and time-consuming. In this work, we propose a method to apply execution models proposed in existing studies without modifying commercial real-time operating systems. We implemented the time-division multiple access (TDMA) and acquisition execution restitution (AER) execution models with pseudo-partition and message queuing on VxWorks 653. Moreover, we propose a multi-TDMA model considering the characteristics of the target hardware. For the interference analysis, we measured the L1 and L2 cache misses and the number of main memory requests. We demonstrated that the interference caused by memory sharing was reduced by at least 60% in the execution model. In particular, multi-TDMA doubled utilization compared to TDMA and also reduced the execution time by 20% compared to the AER model.
Improving Singing Voice Separation Using Curriculum Learning on Recurrent Neural Networks
Authors: Kang Seungtae , Park  Jeong-Sik , Jang  Gil-Jin
Published: April 2020

Single-channel singing voice separation has been considered a difficult task, as it requires predicting two different audio sources independently from mixed vocal and instrument sounds recorded by a single microphone. We propose a new singing voice separation approach based on the curriculum learning framework, in which learning is started with only easy examples and then task difficulty is gradually increased. In this study, we regard the data providing obviously dominant characteristics of a single source as an easy case and the other data as a difficult case. To quantify the dominance property between two sources, we define a dominance factor that determines a difficulty level according to relative intensity between vocal sound and instrument sound. If a given data is determined to provide obviously dominant characteristics of a single source according to the factor, it is regarded as an easy case; otherwise, it belongs to a difficult case. Early stages in the learning focus on easy cases, thus allowing rapidly learning overall characteristics of each source. On the other hand, later stages handle difficult cases, allowing more careful and sophisticated learning. In experiments conducted on three song datasets, the proposed approach demonstrated superior performance compared to the conventional approaches.
Edge Computing-Based Self-Organized Device Network for Awareness Activities of Daily Living in the Home
Authors: Keum Seong Su , Park Yu Jin , Kang Soon Ju
Published: April 2020

Activities of daily living (ADL) are important indicators for awareness of brain health in the elderly, and hospitals use ADL as a standard test for diagnosing chronic brain diseases such as dementia. However, since it is difficult to judge real-life ADL in hospitals, doctors typically predict ADL ability through interviews with patients or accompanying caregivers. Recently, many studies have attempted to diagnose accurate brain health by collecting and analyzing the real-life ADL of patients in their living environments. However, most of these were conducted by constructing and implementing expensive smart homes with the concept of centralized computing, and ADL data were collected from simple data about patients’ home appliance usage and the surrounding environment. Despite the high cost of building a smart home, the collected ADL data are inadequate for predicting accurate brain health. In this study, we developed and used three types of portable devices (wearable, tag, and stationary) that can be easily installed and operated in typical existing houses. We propose a self-organized device network structure based on edge computing that can perform user perception, location perception, and behavioral perception simultaneously. This approach enables us to collect user activity data, analyze ADL in real-time to determine if the user’s behavior was successful or abnormal, and record the physical ability of the user to move between fixed spaces. The characteristics of this proposed system enable us to distinguish patients from other family members and provide real-time notifications after a forgetful or mistaken action. We implemented devices that constitute the edge network of the smart home scenario and evaluated the performance of this system to verify its usefulness.
The Effect of Elevated CO2 on Berry Development and Bunch Structure of Vitis vinifera L. cvs. Riesling and Cabernet Sauvignon
Authors: Wohlfahrt Yvette , Tittmann Susanne , Schmidt Dominik , Rauhut Doris , Honermeier Bernd , Stoll Manfred
Published: April 2020

Carbon dioxide (CO2) as one of the main factors driving climate change is known to increase grapevine growth and yield and could, therefore, have an impact on the fruit quality of vines. This study reports the effects of elevated CO2 (eCO2) on berry development and bunch structure of two grapevine cultivars (Vitis vinifera L. cvs. Riesling and Cabernet Sauvignon) within the VineyardFACE (Free-Air Carbon Dioxide enrichment) experiment, using must analysis and non-invasive fluorescence sensor technology. Berry development was examined on five dates over three consecutive years by analyzing total soluble solids (TSS), pH, total acidity, organic acids, nutrition status, and non-invasive Multiplex measurements. Before harvest, secondary bunches were collected to examine bunch and berry parameters. Results showed that eCO2 had little impact on berry composition of Riesling and Cabernet Sauvignon during berry development, which could be related to bunch structure or single berry weight within single seasons. Elevated CO2 (eCO2) did not result in modified TSS accumulation during ripening but was directly related to the chlorophyll index SFR_R. Higher single berry weights (SBW), higher malic acid (MA), and lower tartaric acid (TAA) were examined at some stages during development of berries under eCO2 levels. Our study provides evidence that eCO2 did alter some bunch and berry parameters without a negative impact on fruit quality.
Mesoporous Carbon as Galvanic-Corrosion Activator Accelerates Fe Degradation
Authors: Shuai Cijun , Li Yulong , Deng Fang , Yang Youwen , Peng Shuping , Qi Fangwei , Shen Lida
Published: April 2020

Iron (Fe) has attracted intensive attention as a bone implant material because of its inherent biodegradability, favorable biocompatibility and mechanical properties. Nevertheless, it degrades too slowly in a physiological environment, which limits its further clinical application. In this work, mesoporous carbon (MC) was introduced into Fe bone implant manufactured via a laser-additive manufacturing process. Particularly, MC possesses a noble standard corrosion potential and excellent electrical conductivity, thus acting as an effective cathode and activating micro-galvanic corrosion in the Fe matrix. More importantly, its high specific surface area enhanced the area ratio between cathode and anode, which further enhanced the galvanic corrosion effect. As a consequence, the corrosion rate was enhanced from 0.09 to 0.24 mm/year based on immersion tests. Besides, Fe/MC composite exhibited good cytocompatibility, as well as excellent mechanical properties. The positive results proved that the Fe/MC composite shows great potential as a bone implant.
Accelerating High-Resolution Seismic Imaging by Using Deep Learning
Authors: Liu Wei , Cheng Qian , Liu Linong , Wang Yun , Zhang Jianfeng
Published: April 2020

The emerging applications of deep learning in solving geophysical problems have attracted increasing attention. In particular, it is of significance to enhance the computational efficiency of the computationally intensive geophysical algorithms. In this paper, we accelerate deabsorption prestack time migration (QPSTM), which can yield higher-resolution seismic imaging by compensating absorption and correcting dispersion through deep learning. This is implemented by training a neural network with pairs of small-sized patches of the stacked migrated results obtained by conventional PSTM and deabsorption QPSTM and then yielding the high-resolution imaging volume by prediction with the migrated results of conventional PSTM. We use an encoder-decoder network to highlight the features related to high-resolution migrated results in a high-order dimension space. The training data set of small-sized patches not only reduces the required high-resolution migrated result (for instance, only several inline is required) but leads to a fast convergence in training. The proposed deep-learning approach accelerates the high-resolution imaging by more than 100 times. Field data is used to demonstrate the effectiveness of the proposed method.
Calibration and Image Reconstruction in a Spot Scanning Detection System for Surface Defects
Authors: Wu Fan , Cao Pin , Du Yubin , Hu Haotian , Yang Yongying
Published: April 2020

Compared to traditional approaches, the spot scanning surface defect evaluation system (SS-SDES) has better performances on the detection of small defects and defect classification for optical surfaces. However, the existing system deviations will cause distortions and even a missing area in the defect image which is reconstructed from the acquired raw data based on the scanning trace, thus degrading the reliability of detection results. To solve these problems, a system calibration method is proposed with the parameterization of these deviations and the modeling of practical scanning trace. A constraint function, to characterize the straightness and scale errors in the image, is defined. Then an optimization is implemented to minimize it and hence to obtain the optimal estimate of the system deviations, which is subsequently used to adjust the system and reconstruct reliable defect images. Additionally, to further enhance the image quality, an image reconstruction method capable of suppressing signal noise through a weighted average strategy is proposed. Experiments show that with our methods, the system deviations are effectively corrected, and a complete and precise defect image with low distortions that are within 1.8 pixels is reconstructed. Therefore, the detection accuracy and reliability of the system can be improved.
Management of Endodontic and Periodontal Lesions: the Role of Regenerative Dentistry and Biomaterials
Authors: Tatullo Marco , Riccitiello Francesco , Rengo Sandro , Marrelli Benedetta , Valletta Rosa , Spagnuolo Gianrico
Published: April 2020

Regenerative dentistry represents a novel interdisciplinary approach involving biomaterials, several molecules and mesenchymal stem cells (MSCs), preferably derived from oral tissues. The pivotal role of MSCs depends on the fact that they can differentiate into different cell lineages and have the strategic role to release bioactive substances that stimulate the renewal and regeneration of damaged tissues. The role of regenerative dentistry is promising in all the branches of dentistry: the most intriguing application is related to the management of endodontic and periodontal defects, overcoming the surgical approach and the implantology as a consequence of a poorly efficient therapeutic plan.
Effect of Textural Features in Remote Sensed Data on Rubber Plantation Extraction at Different Levels of Spatial Resolution
Authors: Zhang Chenchen , Huang Chong , Li He , Liu Qingsheng , Li Jing , Bridhikitti Arika , Liu Gaohuan
Published: April 2020

The expansion of rubber (Hevea brasiliensis) plantations has been a critical driver for the rapid transformation of tropical forests, especially in Thailand. Rubber plantation mapping provides basic information for surveying resources, updating forest subplot information, logging, and managing the forest. However, due to the diversity of stand structure, complexity of the forest growth environment, and the similarity of spectral characteristics between rubber trees and natural forests, it is difficult to discriminate rubber plantation from natural forest using only spectral information. This study evaluated the validity of textural features for rubber plantation recognition at different spatial resolutions using GaoFen-1 (GF-1), Sentinel-2, and Landsat 8 optical data. C-band Sentinel-1 10 m imagery was first used to map forests (including both rubber plantations and natural forests) and non-forests, then the pixels identified as forests in the Sentinel-1 imagery were compared with GF-1, Sentinel-2, and Landsat 8 images to separate rubber plantations and natural forest using two different approaches: a method based on spectral information characteristics only and a method combining spectral and textural features. In addition, we extracted textural features of different window sizes (3 × 3 to 31 × 31) and analyzed the influence of window size on the separability of rubber plantations and natural forests. Our major findings include: (1) the suitable texture extraction window sizes of GF-1, Sentinel-2, and Landsat 8 are 31 × 31, 11 × 11 to 15 × 15, and 3 × 3 to 7 × 7, respectively; (2) correlation (COR) is a robust textural feature in remote sensing images with different resolutions; and (3) compared with classification by spectral information only, the producer’s accuracy of rubber plantations based on GF-1, Sentinel-2, and Landsat 8 was improved by 8.04%, 9.44%, and 8.74%, respectively, and the user’s accuracy was increased by 4.63%, 4.54%, and 6.75%, respectively, when the textural features were introduced. These results demonstrate that the method combining textural features has great potential in delineating rubber plantations.
Generalized Integral Inequalities of Chebyshev Type
Authors: Guzmán Paulo M. , Kórus Péter , Nápoles Valdés Juan E.
Published: April 2020

In this paper, we present a number of Chebyshev type inequalities involving generalized integral operators, essentially motivated by the earlier works and their applications in diverse research subjects.
Evolution of the Human Chromosome 13 Synteny: Evolutionary Rearrangements, Plasticity, Human Disease Genes and Cancer Breakpoints
Authors: Scardino Rita , Milioto Vanessa , Proskuryakova Anastasia A. , Serdyukova Natalia A. , Perelman Polina L. , Dumas Francesca
Published: April 2020

The history of each human chromosome can be studied through comparative cytogenetic approaches in mammals which permit the identification of human chromosomal homologies and rearrangements between species. Comparative banding, chromosome painting, Bacterial Artificial Chromosome (BAC) mapping and genome data permit researchers to formulate hypotheses about ancestral chromosome forms. Human chromosome 13 has been previously shown to be conserved as a single syntenic element in the Ancestral Primate Karyotype; in this context, in order to study and verify the conservation of primate chromosomes homologous to human chromosome 13, we mapped a selected set of BAC probes in three platyrrhine species, characterised by a high level of rearrangements, using fluorescence in situ hybridisation (FISH). Our mapping data on Saguinus oedipus, Callithrix argentata and Alouatta belzebul provide insight into synteny of human chromosome 13 evolution in a comparative perspective among primate species, showing rearrangements across taxa. Furthermore, in a wider perspective, we have revised previous cytogenomic literature data on chromosome 13 evolution in eutherian mammals, showing a complex origin of the eutherian mammal ancestral karyotype which has still not been completely clarified. Moreover, we analysed biomedical aspects (the OMIM and Mitelman databases) regarding human chromosome 13, showing that this autosome is characterised by a certain level of plasticity that has been implicated in many human cancers and diseases.
Altered Expression of GABAergic Markers in the Forebrain of Young and Adult Engrailed-2 Knockout Mice
Authors: Provenzano Giovanni , Gilardoni Angela , Maggia Marika , Pernigo Mattia , Sgadò Paola , Casarosa Simona , Bozzi Yuri
Published: April 2020

Impaired function of GABAergic interneurons, and the subsequent alteration of excitation/inhibition balance, is thought to contribute to autism spectrum disorders (ASD). Altered numbers of GABAergic interneurons and reduced expression of GABA receptors has been detected in the brain of ASD subjects and mouse models of ASD. We previously showed a reduced expression of GABAergic interneuron markers parvalbumin (PV) and somatostatin (SST) in the forebrain of adult mice lacking the Engrailed2 gene (En2-/- mice). Here, we extended this analysis to postnatal day (P) 30 by using in situ hybridization, immunohistochemistry, and quantitative RT-PCR to study the expression of GABAergic interneuron markers in the hippocampus and somatosensory cortex of En2-/- and wild type (WT) mice. In addition, GABA receptor subunit mRNA expression was investigated by quantitative RT-PCR in the same brain regions of P30 and adult En2-/- and WT mice. As observed in adult animals, PV and SST expression was decreased in En2-/- forebrain of P30 mice. The expression of GABA receptor subunits (including the ASD-relevant Gabrb3) was also altered in young and adult En2-/- forebrain. Our results suggest that GABAergic neurotransmission deficits are already evident at P30, confirming that neurodevelopmental defects of GABAergic interneurons occur in the En2 mouse model of ASD.
The Monetary Value of Human Lives Lost to Suicide in the African Continent: Beating the African War Drums
Authors: Kirigia Joses M. , Muthuri Rosenabi D.K. , Muthuri Newton G.
Published: April 2020

Background: Suicide is an important public health problem in the African continent whose economic burden remains largely unknown. This study estimated the monetary value of human lives lost due to suicide in the African continent in 2017. Methods: The human capital approach was applied to monetarily value the years of life lost due to premature mortality from suicide deaths (SD) among 54 African countries. A 3% discount rate was used to convert future losses into their present values. The sensitivity of monetary value of human lives lost to changes in discount rate and average life expectancy was tested. Results: The 75,505 human lives lost from suicide had a grand total monetary value of International Dollars (Int$) 6,989,963,325; and an average present value of Int$ 92,576 per SD. About 31.1% of the total monetary value of SD was borne by high-income and upper-middle-income countries (Group 1); 54.4% by lower-middle-income countries (Group 2); and 14.5% by low-income countries (Group 3). The average monetary value per human life lost from SD was Int$ 234,244 for Group 1, Int$ 109,545 for Group 2 and Int$ 32,223 for Group 3. Conclusions: Evidence shows that suicide imposes a substantive economic burden on African economies. The evidence reinforces the case for increased investments to ensure universal coverage of promotive, preventive, curative and rehabilitative mental health services.
Ultramorphological Characteristics of Falsogastrallus sauteri Pic (Coleoptera: Ptinidae) and a New Species of Cephalonomia Westwood (Hymenoptera: Bethylidae): A Book-Boring Beetle and Its Natural Enemy in Taiwan
Authors: Ho Yu-Hsiang , Hsiao Yun , Terayama Mamoru , Chan Mei-Ling
Published: April 2020

Libraries are invaluable resources, documenting significant events that have shaped human history. However, the preservation of old books is severely threatened by insects commonly referred to as bookworms. In this study, a sample of infested books in a historic library in Taiwan was randomly selected and examined. An anobiid book-boring beetle, Falsogastrallus sauteri Pic, 1914 (Coleoptera: Ptinidae) was identified as the major bookworm species present. To facilitate its identification, both adults and larvae of F. sauteri are redescribed, with emphasis on its ultramorphological characteristics as revealed by scanning electronic microscopy. Furthermore, an undescribed parasitoid wasp in the Bethylidae was discovered in the frass, holes and tunnels created by F. sauteri. The new species, Cephalonomia formosiensis sp. nov. is described, and we suggest that it probably uses F. sauteri as host.
Monthly and Quarterly Sea Surface Temperature Prediction Based on Gated Recurrent Unit Neural Network
Authors: Zhang Zhen , Pan Xinliang , Jiang Tao , Sui Baikai , Liu Chenxi , Sun Weifu
Published: April 2020

The sea surface temperature (SST) is an important parameter of the energy balance on the Earth’s surface. SST prediction is crucial to marine production, marine protection, and climate prediction. However, the current SST prediction model still has low precision and poor stability. In this study, a medium and long-term SST prediction model is designed on the basis of the gated recurrent unit (GRU) neural network algorithm. This model captures the SST time regularity by using the GRU layer and outputs the predicted results through the fully connected layer. The Bohai Sea, which is characterized by a large annual temperature difference, is selected as the study area, and the SSTs on different time scales (monthly and quarterly) are used to verify the practicability and stability of the model. The results show that the designed SST prediction model can efficiently fit the results of the real sea surface temperature, and the correlation coefficient is above 0.98. Regardless of whether monthly or quarterly data are used, the proposed network model performs better than long short-term memory in terms of stability and accuracy when the length of the prediction increases. The root mean square error and mean absolute error of the predicted SST are mostly within 0–2.5 °C.
Role of Nonlinear Four-Wave Interactions Source Term on the Spectral Shape
Authors: Ponce de León Sonia , Osborne Alfred R.
Published: April 2020

The goal of this paper is to investigate the importance of the four-wave nonlinear interactions (SNL4) on the shape of the power spectrum of ocean waves. To this end, the following results are discussed: a number of authors have conducted modern experimental measurements of ocean waves over the past decades and found that the measured power spectrum has (a) a very high central peak (characterized by the parameter γ, developed in the 1970s in the JONSWAP program) and (b) enhanced high-frequency channels which lead to the phenomenon of “bimodality”, also a well-known phenomenon. We discuss how a numerical hindcast of the Draupner storm (1995) with the standard code WAVEWATCH-III with full Boltzmann interactions also reflects these previously experimentally determined spectral shapes. Our results suggest that the use of the full Boltzmann interactions (as opposed to the discrete interaction approximation often employed for forecasting/hindcasting) is important for obtaining this characteristic physical spectral shape of the power spectrum.
A Tidal Hydrodynamic Model for Cook Inlet, Alaska, to Support Tidal Energy Resource Characterization
Authors: Wang Taiping , Yang Zhaoqing
Published: April 2020

Cook Inlet in Alaska has been identified as a prime site in the U.S. for potential tidal energy development, because of its enormous tidal power potential that accounts for nearly one-third of the national total. As one important step to facilitate tidal energy development, a tidal hydrodynamic model based on the unstructured-grid, finite-volume community ocean model (FVCOM) was developed for Cook Inlet to characterize the tidal stream energy resource. The model has a grid resolution that varies from about 1000 m at the open boundary to 100–300 m inside the Inlet. Extensive model validation was achieved by comparing model predictions with field observations for tidal elevation and velocity at various locations in Cook Inlet. The error statistics confirmed the model performs reasonably well in capturing the tidal dynamics in the system, e.g., R2 > 0.98 for tidal elevation and generally > 0.9 for velocity. Model results suggest that tides in Cook Inlet evolve from progressive waves at the entrance to standing waves at the upper Inlet, and that semi-diurnal tidal constituents are amplified more rapidly than diurnal constituents. The model output was used to identify hotspots that have high energy potential and warrant additional velocity and turbulence measurements such as East Foreland, where averaged power density exceeds 5 kw/m2. Lastly, a tidal energy extraction simulation was conducted for a hypothetical turbine farm configuration at the Forelands cross section to evaluate tidal energy extraction and resulting changes in far-field hydrodynamics.
Numerical and Experimental Comparison of Ducted and Non-Ducted Propellers
Authors: Villa Diego , Gaggero Stefano , Tani Giorgio , Viviani Michele
Published: April 2020

Ducted propellers are unconventional systems that are usually adopted for ship propulsion. These devices have recently been studied with medium-fidelity computational fluid dynamics code (based on the potential flow hypothesis) with promising results. However, these tools, even though they provide a good prediction of the forces and moments generated by the blades and the duct, are not able to provide insight into the flow field characteristics due to their crude flow approximations. On the contrary, modern high-fidelity viscous-based computational fluid dynamics codes could give a better description of the near and far-field flow of these particular devices. In the present paper, forces and the most significant features of the flow field around two ducted propellers are analyzed by means of both experimental and computational fluid dynamics approaches. In particular, accelerating and decelerating ducts are considered, and we demonstrate the ability of the adopted solver to accurately predict the performance and the flow field for both types. These results, in particular for the less-studied decelerating duct, designate CFD as a useful tool for reliable designs.
Profile Optimization of Hydraulic, Polymeric, Sliding Seals by Minimizing an Objective Function of Leakage, Friction and Abrasive Wear
Authors: Nikas George K.
Published: April 2020

Hydraulic dynamic seals for reciprocating or alternating motion are machine elements with widespread applications in the automotive, aerospace, marine, pharmaceutical and several other industrial sectors. They have been under commercial development for many decades, and are often met in critical positions, consuming a considerable amount of energy during operation. An objective function of mass leakage rate, friction force and an abrasive-wear representative term is proposed in the present study to evaluate the performance of hydraulic, polymeric sliding seals under suitable constraints. Using Variational Calculus, analytical and numerical techniques, the objective function is minimized, resulting in an optimal seal profile that maximizes sealing performance for given, steady-state operating conditions, in additional consideration of the structural integrity and manufacturability of the modified seal. The obtained seal shape and related pressure distribution are reminiscent of those for U-cup and step seals, designs that dominate the industry. In the course of the mathematical analysis, some major obstacles are documented that show how sensitive and complicated sealing performance really is.
Mathematical Aspects of Krätzel Integral and Krätzel Transform
Authors: Mathai Arak M. , Haubold Hans J.
Published: April 2020

A real scalar variable integral is known in the literature by different names in different disciplines. It is basically a Bessel integral called specifically Krätzel integral. An integral transform with this Krätzel function as kernel is known as Krätzel transform. This article examines some mathematical properties of Krätzel integral, its connection to Mellin convolutions and statistical distributions, its computable representations, and its extensions to multivariate and matrix-variate cases, in both the real and complex domains. An extension in the pathway family of functions is also explored.
Developing Stress Management Programs in a Public Primary Healthcare Institution: Should We Consider Health Workers’ Sociodemographic Groups?
Authors: Dudutienė Daiva , Juodaitė-Račkauskienė Audronė , Stukas Rimantas
Published: April 2020

Background and Objectives: An essential part of occupational stress management is identifying target groups and developing a wellbeing program that tailors interventions to the specific needs of the target groups. This study aims to explore whether psychosocial risk determinants and organizational intervention objects differ across employees’ groups based on sociodemographic factors in a Lithuanian public primary healthcare institution. Methods: All 690 health workers of the institution were invited to participate (response rate 68%) in a cross-sectional survey between February and March 2017. The questionnaire contained items related to sociodemographic factors (gender, age, job seniority, education, and occupation), 14 psychosocial risk determinants, and 10 organisational intervention objects. Results: The results of the study showed that differences by gender were not statistically significant except for one organisational intervention object (work–life balance). Only a few organisational intervention objects (justice of reward, matching to the job demand, and variety of tasks) had mean rank scores differing statistically across age and job seniority groups. Five organisational intervention objects (work–life balance, variety of tasks, communication, manager feedback, and stress management training) had mean rank scores differing statistically across education groups, and all organisational intervention objects (except stress management training) had mean rank scores differing statistically across occupational groups. Regarding psychosocial risk determinants, excessive work pace had mean rank scores differing statistically across age and job seniority groups. Four (overtime, unclear role, conflicting roles, and being under-skilled) and six psychosocial risk determinants (work overload, overtime, tight deadlines, unclear role, being under-skilled, and responsibility) had mean scores differing statistically across education and occupational groups, respectively. Statistical significance was considered with p-value < 0.05 and 95% confidence interval. Conclusions: The findings showed that different psychosocial risk determinants and organizational interventional objects were emphasized by different sociodemographic groups in the institution, but they did not impact groups in the same measure. Therefore, it is crucial to start by determining the risk group’s specific needs before developing and implementing stress management programs.
Germ-Free Swiss Webster Mice on a High-Fat Diet Develop Obesity, Hyperglycemia, and Dyslipidemia
Authors: Logan Isabelle E. , Bobe Gerd , Miranda Cristobal L. , Vasquez-Perez Stephany , Choi Jaewoo , Lowry Malcolm B. , Sharpton Thomas J. , Morgun Andrey , Maier Claudia S. , Stevens Jan F. , Shulzhenko Natalia , Gombart Adrian F.
Published: April 2020

A calorie-dense diet is a well-established risk factor for obesity and metabolic syndrome (MetS), whereas the role of the intestinal microbiota (IMB) in the development of diet-induced obesity (DIO) is not completely understood. To test the hypothesis that Swiss Webster (Tac:SW) mice can develop characteristics of DIO and MetS in the absence of the IMB, we fed conventional (CV) and germ-free (GF) male Tac:SW mice either a low-fat diet (LFD; 10% fat derived calories) or a high-fat diet (HFD; 60% fat derived calories) for 10 weeks. The HFD increased feed conversion and body weight in GF mice independent of the increase associated with the microbiota in CV mice. In contrast to CV mice, GF mice did not decrease feed intake on the HFD and possessed heavier fat pads. The HFD caused hyperglycemia, hyperinsulinemia, and impaired glucose absorption in GF mice independent of the increase associated with the microbiota in CV mice. A HFD also elevated plasma LDL-cholesterol and increased hepatic triacylglycerol, free fatty acids, and ceramides in all mice, whereas hypertriglyceridemia and increased hepatic medium and long-chain acylcarnitines were only observed in CV mice. Therefore, GF male Tac:SW mice developed several detrimental effects of obesity and MetS from a high-fat, calorie dense diet.
Bovine Papillomavirus Type 2 Infection Associated with Papillomatosis of the Amniotic Membrane in Water Buffaloes (Bubalus bubalis)
Authors: Russo Valeria , Roperto Franco , De Biase Davide , Cerino Pellegrino , Urraro Chiara , Munday John S. , Roperto Sante
Published: April 2020

Multiple papillomatous nodules were observed scattered over the amniotic membrane in six water buffaloes that had recently aborted. Grossly, some of the nodules had multiple villous projections while others appeared as single prominent conical or cylindrical horns. Histology revealed folded hyperplastic and hyperkeratotic epithelium supported by a narrow fibro-vascular stalk. Using PCR, sequences of the bovine Deltapapillomavirus type 2 (BPV-2) E5 gene were amplified from the amniotic papillomas. Furthermore, expression of the E5 gene was detected using reverse transcription (RT)-PCR. Western blotting revealed BPV-2 E5 oncoprotein as well as L1 protein, suggesting both abortive and productive infection. Additionally, a functional complex composed of BPV-2 E5 oncoprotein and the phosphorylated PDGFβR was detected, which is consistent with the activation of PDGFβR by the interaction with BPV-2 E5 oncoprotein. These results demonstrate that BPV-2 can infect the amnion of water buffaloes and suggest that this infection may cause proliferation of the epithelial cells of the amnion. While the precise pathogenesis in uncertain, it is possible that BPV-2 infection of stratified squamous epithelial cells within squamous metaplasia foci and/or amniotic plaques could lead to papilloma formation. Papillomavirus-associated amniotic papillomas have not previously been reported in any species, including humans.
Effect of Food and an Animal’s Sex on P-Glycoprotein Expression and Luminal Fluids in the Gastrointestinal Tract of Wistar Rats
Authors: Dou Liu , Gavins Francesca K. H. , Mai Yang , Madla Christine M. , Taherali Farhan , Orlu Mine , Murdan Sudaxshina , Basit Abdul W.
Published: April 2020

The rat is one of the most commonly used animal models in pre-clinical studies. Limited information between the sexes and the effect of food consumption on the gastrointestinal (GI) physiology, however, is acknowledged or understood. This study aimed to investigate the potential sex differences and effect of food intake on the intestinal luminal fluid and the efflux membrane transporter P-glycoprotein (P-gp) along the intestinal tract of male and female Wistar rats. To characterise the intestinal luminal fluids, pH, surface tension, buffer capacity and osmolality were measured. Absolute P-gp expression along the intestinal tract was quantified via liquid chromatography-tandem mass spectrometry (LC-MS/MS). In general, the characteristics of the luminal fluids were similar in male and female rats along the GI tract. In fasted male rats, the absolute P-gp expression gradually increased from the duodenum to ileum but decreased in the colon. A significant sex difference (p < 0.05) was identified in the jejunum where P-gp expression in males was 83% higher than in females. Similarly, ileal P-gp expression in male rats was approximately 58% higher than that of their female counterparts. Conversely, following food intake, a significant sex difference (p < 0.05) in P-gp expression was found but in a contrasting trend. Fed female rats expressed much higher P-gp levels than male rats with an increase of 77% and 34% in the jejunum and ileum, respectively. A deeper understanding of the effects of sex and food intake on the absorption of P-gp substrates can lead to an improved translation from pre-clinical animal studies into human pharmacokinetic studies.
Phenformin Attenuates Renal Injury in Unilateral Ureteral Obstructed Mice without Affecting Immune Cell Infiltration
Authors: Nørgård Mikkel Ø. , Christensen Michael , Mutsaers Henricus A.M. , Nørregaard Rikke
Published: April 2020

Phenformin and metformin are antihyperglycemic drugs that belong to the class of biguanides. Previously, we demonstrated that metformin elicits renoprotective effects in unilateral ureteral obstructed mice by reducing the infiltration of immune cells into the kidney. Since phenformin is a more potent drug as compared to metformin, we investigated the renoprotective properties of phenformin. We studied the efficacy of both drugs using mice that underwent unilateral ureteral obstruction. Renal damage was evaluated on RNA and protein level by qPCR, Western blotting, and immunohistochemistry. Moreover, we studied immune cell infiltration using flow cytometry. Both biguanides significantly reduced UUO-induced kidney injury, as illustrated by a reduction in KIM-1 protein expression. In addition, both metformin and phenformin impacted the gene expression of several inflammatory markers but to a different extent. Moreover, in contrast to metformin, phenformin did not impact immune cell infiltration into UUO kidneys. In conclusion, we demonstrated that phenformin has similar renoprotective effects as metformin, but the mechanism of action differs, and phenformin is more potent. The beneficial effects of phenformin are probably due to inhibition of the STAT3 pathway and mitochondrial complex I. Further research is needed to unveil the therapeutic potential of phenformin for the treatment of renal injury, either at low, non-toxic concentrations or as part of a combination therapy.
Gelatin Nanoparticles-HPMC Hybrid System for Effective Ocular Topical Administration of Antihypertensive Agents
Authors: Esteban-Pérez Sergio , Andrés-Guerrero Vanessa , López-Cano José Javier , Molina-Martínez Irene , Herrero-Vanrell Rocio , Bravo-Osuna Irene
Published: April 2020

The increment in ocular drug bioavailability after topical administration is one of the main challenges in pharmaceutical technology. For several years, different strategies based on nanotechnology, hydrogels or implants have been evaluated. Nowadays, the tolerance of ophthalmic preparations has become a critical issue and it is essential to the use of well tolerated excipients. In the present work, we have explored the potential of gelatin nanoparticles (GNPs) loaded with timolol maleate (TM), a beta-adrenergic blocker widely used in the clinic for glaucoma treatment and a hybrid system of TM-GNPs included in a hydroxypropyl methylcellulose (HPMC) viscous solution. The TM- loaded nanoparticles (mean particle size of 193 ± 20 nm and drug loading of 0.291 ± 0.019 mg TM/mg GNPs) were well tolerated both in vitro (human corneal cells) and in vivo. The in vivo efficacy studies performed in normotensive rabbits demonstrated that these gelatin nanoparticles were able to achieve the same hypotensive effect as a marketed formulation (0.5% TM) containing a 5-fold lower concentration of the drug. When comparing commercial and TM-GNPs formulations with the same TM dose, nanoparticles generated an increased efficacy with a significant (p < 0.05) reduction of intraocular pressure (IOP) (from 21% to 30%) and an augmentation of 1.7-fold in the area under the curve (AUC)(0–12h). On the other hand, the combination of timolol-loaded nanoparticles (TM 0.1%) and the viscous polymer HPMC 0.3%, statistically improved the IOP reduction up to 30% (4.65 mmHg) accompanied by a faster time of maximum effect (tmax = 1 h). Furthermore, the hypotensive effect was extended for four additional hours, reaching a pharmacological activity that lasted 12 h after a single instillation of this combination, and leading to an AUC(0–12h) 2.5-fold higher than the one observed for the marketed formulation. According to the data presented in this work, the use of hybrid systems that combine well tolerated gelatin nanoparticles and a viscous agent could be a promising alternative in the management of high intraocular pressure in glaucoma.
An Interspecies Molecular and Functional Study of Organic Cation Transporters at the Blood-Brain Barrier: From Rodents to Humans
Authors: Chaves Catarina , Campanelli Federica , Chapy Hélène , Gomez-Zepeda David , Glacial Fabienne , Smirnova Maria , Taghi Meryam , Pallud Johan , Perrière Nicolas , Declèves Xavier , Menet Marie-Claude , Cisternino Salvatore
Published: April 2020

Organic cation transporters (OCTs) participate in the handling of compounds in kidneys and at the synaptic cleft. Their role at the blood-brain barrier (BBB) in brain drug delivery is still unclear. The presence of OCT1,2,3 (SLC22A1-3) in mouse, rat and human isolated brain microvessels was investigated by either qRT-PCR, quantitative proteomics and/or functional studies. BBB transport of the prototypical substrate [3H]-1-methyl-4-phenylpyridinium ([3H]-MPP+) was measured by in situ brain perfusion in six mouse strains and in Sprague Dawley rats, in primary human brain microvascular endothelial cells seeded on inserts, in the presence or absence of OCTs and a MATE1 (SLC49A1) inhibitor. The results show negligible OCT1 (SLC22A1) and OCT2 (SLC22A2) expression in either mice, rat or human brain microvessels, while OCT3 expression was identified in rat microvessels by qRT-PCR. The in vitro human cellular uptake of [3H]-MPP+ was not modified by OCTs/MATE-inhibitor. Brain transport of [3H]-MPP+ remains unchanged between 2- and 6-month old mice, and no alteration was observed in mice and rats with inhibitors. In conclusion, the evidenced lack of expression and/or functional OCTs and MATE at the BBB allows the maintenance of the brain homeostasis and function as it prevents an easy access of their neurotoxicant substrates to the brain parenchyma.