bluuebunny/crossref_metadata_2025 huggingface dataset:
Creep Motion of Elastic Interfaces Driven in a Disordered Landscape
Authors: Ferrero Ezequiel E. , Foini Laura , Giamarchi Thierry , Kolton Alejandro B. , Rosso Alberto
Published: March 2021

The thermally activated creep motion of an elastic interface weakly driven on a disordered landscape is one of the best examples of glassy universal dynamics. Its understanding has evolved over the past 30 years thanks to a fruitful interplay among elegant scaling arguments, sophisticated analytical calculations, efficient optimization algorithms, and creative experiments. In this article, starting from the pioneer arguments, we review the main theoretical and experimental results that lead to the current physical picture of the creep regime. In particular, we discuss recent works unveiling the collective nature of such ultraslow motion in terms of elementary activated events. We show that these events control the mean velocity of the interface and cluster into “creep avalanches” statistically similar to the deterministic avalanches observed at the depinning critical threshold. The associated spatiotemporal patterns of activated events have been recently observed in experiments with magnetic domain walls. The emergent physical picture is expected to be relevant for a large family of disordered systems presenting thermally activated dynamics.
The Rise of Local Politics: A Global Review
Authors: Le Galès Patrick
Published: March 2021

Not all politics is local. Not even local politics is necessarily local. The reemergence of local politics is not comparable to the nationalization of politics but is rather an element making multilevel policies more or less interconnected. This global review (not including North America) suggests that the rise of local politics is explained by three set of processes—( a) democratization, including protest, ( b) economic globalization, urbanization, and the deepening of territorial inequalities, and ( c) decentralization or deconcentration and the rise of local governance and policies. The rise of local politics is not a revival of the past but an element of the politics of scale taking. All over the world, local politics is increasingly about policies, governance, and political choice.
Assessment of the effects of Syk and BTK inhibitors on GPVI-mediated platelet signaling and function
Authors: Zheng Tony J. , Lofurno Elizabeth R. , Melrose Alexander R. , Lakshmanan Hari Hara Sudhan , Pang Jiaqing , Phillips Kevin G. , Fallon Meghan E. , Kohs Tia C. L. , Ngo Anh T. P. , Shatzel Joseph J. , Hinds Monica T. , McCarty Owen J. T. , Aslan Joseph E.
Published: March 2021

Spleen tyrosine kinase (Syk) and Bruton’s tyrosine kinase (BTK) play critical roles in platelet physiology, facilitating intracellular immunoreceptor tyrosine-based activation motif (ITAM)-mediated signaling downstream of platelet glycoprotein VI (GPVI) and GPIIb/IIIa receptors. Small molecule tyrosine kinase inhibitors (TKIs) targeting Syk and BTK have been developed as antineoplastic and anti-inflammatory therapeutics and have also gained interest as antiplatelet agents. Here, we investigate the effects of 12 different Syk and BTK inhibitors on GPVI-mediated platelet signaling and function. These inhibitors include four Syk inhibitors, Bay 61-3606, R406 (fostamatinib), entospletinib, TAK-659; four irreversible BTK inhibitors, ibrutinib, acalabrutinib, ONO-4059 (tirabrutinib), AVL-292 (spebrutinib); and four reversible BTK inhibitors, CG-806, BMS-935177, BMS-986195, and fenebrutinib. In vitro, TKIs targeting Syk or BTK reduced platelet adhesion to collagen, dense granule secretion, and alpha granule secretion in response to the GPVI agonist cross-linked collagen-related peptide (CRP-XL). Similarly, these TKIs reduced the percentage of activated integrin αIIbβ3 on the platelet surface in response to CRP-XL, as determined by PAC-1 binding. Although all TKIs tested inhibited phospholipase C γ2 (PLCγ2) phosphorylation following GPVI-mediated activation, other downstream signaling events proximal to phosphoinositide 3-kinase (PI3K) and PKC were differentially affected. In addition, reversible BTK inhibitors had less pronounced effects on GPIIb/IIIa-mediated platelet spreading on fibrinogen and differentially altered the organization of PI3K around microtubules during platelets spreading on fibrinogen. Select TKIs also inhibited platelet aggregate formation on collagen under physiological flow conditions. Together, our results suggest that TKIs targeting Syk or BTK inhibit central platelet functional responses but may differentially affect protein activities and organization in critical systems downstream of Syk and BTK in platelets.
Gastric accommodation influences proximal gastric and total gastric emptying in concurrent measurements conducted in healthy volunteers
Authors: Wang Xiao Jing , Burton Duane D. , Breen-Lyles Margaret , Camilleri Michael
Published: March 2021

In vivo human studies evaluated concurrently the volume of the stomach during fasting and after a solid and liquid meal using a new SPECT-based method. Although fasting gastric volumes did not impact the rates of gastric emptying, both postprandial and accommodation volumes of the whole and proximal stomach were significantly correlated with gastric emptying. Larger stomach volumes were associated with slower gastric emptying.
Using nutrient-rich solutions and adding multiple cytoprotective agents as new strategies to develop lung preservation solutions
Authors: Jing Lei , Konoeda Hisato , Keshavjee Shaf , Liu Mingyao
Published: March 2021

Commonly, donor lungs are preserved with low-potassium dextran glucose solution at low temperature. We hypothesized that adding nutrients and/or cytoprotective agents to preservation solutions improves donor lung quality. Human lung epithelial cells and human pulmonary microvascular endothelial cells cultured at 37°C with serum containing medium were switched to designated testing solutions at 4°C with 50% O2 for different cold ischemic time, followed by switching back to serum containing culture medium at 37°C to simulate reperfusion. We found that bicarbonate buffer system should be avoided in preservation solution. When pH was maintained at physiological levels, cell culture media showed better cell survival than in low-potassium dextran glucose solution. Phosphate-buffered cell culture media were further improved by adding colloid dextran 40. When rat donor lungs were preserved at 4°C for 24 h, phosphate-buffered Roswell Park Memorial Institute-1640 medium [RPMI-1640(p)] plus dextran 40 or adding cytoprotective agents (alpha 1 antitrypsin, raffinose, and glutathione) to low-potassium dextran glucose solution prevented alveolar wall swelling, apoptosis, activation of endothelial cells, and cellular edema. Using nutrient-rich solution and/or adding multiple cytoprotective agents is a new direction for designing and developing organ preservation solutions. Cell culture model, as a screening tool, reduces the use of animals and provides potential underlying mechanisms.
Choices change the temporal weighting of decision evidence
Authors: Talluri Bharath Chandra , Urai Anne E. , Bronfman Zohar Z. , Brezis Noam , Tsetsos Konstantinos , Usher Marius , Donner Tobias H.
Published: March 2021

The psychology and neuroscience of decision-making have extensively studied the accumulation of decision-relevant information toward a categorical choice. Much fewer studies have assessed the impact of a choice on the processing of subsequent information. Here, we show that intermittent choices during a protracted stream of input reduce the sensitivity to subsequent decision information and transiently boost arousal. Choices might trigger a state change in the neural machinery for decision-making.
Estimating the effects of slicing on the electrophysiological properties of spinal motoneurons under normal and disease conditions
Authors: Mousa Mohamed H. , Elbasiouny Sherif M.
Published: March 2021

Although slice recordings from motoneurons are being widely used, the effects of slicing on the measured motoneuron electrical properties under normal and disease conditions have not been assessed. Using high-fidelity cell models of neonatal WT and SOD cells, we examined the effects of slice thickness, soma position within the slice, and slice orientation. Our results offer information that enhances the rigor of MN electrophysiological data measured from the slice preparation under normal and disease conditions.
Voltage distributions in extracellular brain recordings
Authors: Swindale Nicholas V. , Rowat Peter , Krause Matthew , Spacek Martin A. , Mitelut Catalin
Published: March 2021

We show that the voltage distributions in brain recordings, including high-pass extracellular recordings, the LFP, and human EEG, are accurately described by a Gaussian within ±1.5 standard deviations from zero, with heavy, exponential tails outside these limits. This offers a principled way of setting event detection thresholds in high-pass recordings. It also offers a means for identifying event-like, transient signals in LFP and EEG recordings which may correlate with other neural phenomena.
Effects of Dendrobium Polysaccharides on the Functions of Human Skin Fibroblasts and Expression of Matrix Metalloproteinase-2 under High-Glucose Conditions
Authors: Li Yajia , Cao Ziqin , Li Qiangxiang , Wang Chenxu , Zhou Zhuo
Published: March 2021

The effects of Dendrobium polysaccharides (PDC) on the functions of human skin fibroblasts (HSFs) and expression of matrix metalloproteinase-2 under high-glucose conditions and exploration of the underlying mechanism remain unclear. We used the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) analysis and flow cytometry to evaluate the cell viability and apoptosis. The collagen levels were determined by the Sircol™ Collagen Assay. Real-time quantitative polymerase chain reaction (RT-PCR) was used to detect the expression of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase inhibitor (TIMP-2) mRNA. We found the following: (1) under the high-glucose condition, the HSF cell viability, the expression of TIMP-2 mRNA, and the collagen levels were reduced, while the apoptosis rate and the expression of MMP-2 mRNA increased (

P
<
0.05

). (2) In the high-glucose + PDC group, the PDC reversed the changes in the collagen level, viability, and apoptosis rate of the HSF cells caused by high glucose, with the expression of protein and TIMP-2 mRNA increased and the level of MMP-2 mRNA decreased (

P
<
0.05

). This is the first time attempting to reveal that PDC can exhibit protective effects on HSF under high-glucose conditions, which may be related to the upregulation of the TIMP-2 expression and inhibition of the MMP-2 expression.
The Use of Technology in the Management of Orthodontic Treatment-Related Pain
Authors: Marya Anand , Venugopal Adith
Published: March 2021

Orthodontic pain is one of the negatives associated with fixed orthodontic treatment that cannot be avoided. This pain usually comes around the wire placement period and gradually decreases once the endogenous analgesic mechanisms start functioning. Over the years, several treatment modalities have been utilized for relief from orthodontic pain, and these include mechanical, behavior modification, and pharmacological methods. However, in the last decade, there are several newer methods employing the use of technology that have come up and are being used for alleviating pain. From computerized indirect bonding to virtual treatment planning, technology has slowly become a vital part of an orthodontist’s repertoire. The digital age is here, and orthodontics must embrace the use of technology to help improve the quality of life of patients.
Some Fixed-Point Results via Mix-Type Contractive Condition
Authors: Acar Özlem
Published: March 2021

We consider a fixed-point problem for mappings involving a rational type and almost type contraction on complete metric spaces. To do this, we are using

F

-contraction and

H
,
φ

-contraction. We also present an example to illustrate our result.
Flexural Behavior of Innovative Posttensioned Composite Beams with Corrugated Steel Webs
Authors: Li Xiang , Yang Tao , Zhang Yongbing , Zhang Yun , Shen Taosheng
Published: March 2021

Steel‐concrete composite beams with corrugated steel webs (CSWs) usually have concrete flanges that are prone to crack under tension, and an innovative posttensioned composite beam (IPCB) with CSWs has been proposed previously to overcome this shortcoming. Here, an IPCB with CSWs is manufactured and submitted to a flexural test to investigate its flexural behavior, based on which finite element (FE) models with different parameters are developed and analyzed using the ANSYS software. The effects of the span‐to‐depth ratio, concrete compressive strength, initial effective prestress, width of the upper concrete flange, and yield strength of the steel tubes on the flexural behavior of the IPCBs with CSWs are discussed. Numerical results show that the span‐to‐depth ratio of the beam and the yield strength of the steel tube have a considerable effect on the ultimate load‐carrying capacity of the IPCB, which increases by 48.2% when the depth of the CSWs is increased from 240 to 400 mm and by 21.8% when the yield strength of the steel tubes is increased from 295 to 395 MPa. The plane‐section assumption is unsuitable for IPCBs. Almost all the unbonded posttensioning strands in the beams yield for the specimens at ultimate state. The normal stress is distributed unevenly across the width of the upper concrete flange, and the maximum shear lag coefficient is 1.17. Based on the numerical results, a calculation method is established to evaluate the bending moment resistance of an IPCB with CSWs. Comparison shows that the theoretical results in accordance with the proposed method agree well with the numerical results.
Optimization Approach for Yard Crane Scheduling Problem with Uncertain Parameters in Container Terminals
Authors: Liu Wenqian , Zhu Xiaoning , Wang Li , Yan Baicheng , Zhang Xuewei
Published: March 2021

As the core operational issue in container terminals, yard crane scheduling problem directly affects the overall operation efficiency of port connecting highway or railway transportation and sea transportation. In practice, the scheduling of yard cranes is subject to many uncertain factors, so the scheme may be inapplicable and needs to be adjusted. From the perspective of proactive strategy, considering fluctuations in arrival time of external trucks as well as varied handling volume of yard cranes, a stochastic programming model is established in this paper to obtain a fixed scheme with the minimum expected value of yard crane makespan and total task waiting time over all the scenarios. The scheme does not require rescheduling when facing different situations. Subsequently, two algorithms based on certain rules are proposed to obtain the yard crane operation scheme in the deterministic environment, which are taken as the basic solution in the uncertain conditions, and then a tailored genetic algorithm is adopted to find the optimal solution with good adaptability to the uncertain scenarios. Finally, we use small-scale examples to compare the performance of algorithms in the deterministic and uncertain environment and then analyze the relationship between different yard crane configurations and the number of tasks. Large-scale experiments are performed to study the operation efficiency of the storage yard with different handling volumes assigned to each yard crane.
Cutaneous Lymphadenoma: A Case of Recurrence after Shave Excision
Authors: Rajabi Fateme , Kamyab Kambiz , Firooz Alireza
Published: March 2021

Cutaneous lymphadenoma (CL) is a rare skin tumor supposedly derived from the pilosebaceous unit. Since its description in 1987, fewer than 60 cases have been documented. Herein we report a case of CL presenting as a small nodule on the forehead of a young female. The lesion recurred two years after shave excision of a similar lesion. The histopathological examination revealed interconnected islands, sheets, and trabeculae consisting of two distinct types of cells within a sclerotic stroma, a peripheral rim of palisading basophilic cells, and central epithelial cells with eosinophilic to clear cytoplasm. A dense infiltration with prominent lymphocytes and few plasma cells dominated the stroma and permeated the epithelial nests. This case represents the recurrence of this type of skin tumor after shave excision and thus highlights the importance of complete margin-free excision of such lesions.
Whether the Middle Eocene Salt-Forming Brine in the Kuqa Basin Reached the Potash-Forming Stage: Quantitative Evidence from Halite Fluid Inclusions
Authors: Xu Yang , Cao Yangtong , Liu Chenglin
Published: March 2021

The Kuqa Basin is an important potentially potash-bearing basin in China, and thick salt-bearing strata were deposited under the influence of multistage Tethyan transgression-regression cycles during the Eocene. At present, research on the process of potash formation in the Kuqa Basin has mostly focused on traditional salt mineralogy, whole-rock geochemistry, and evaporite sedimentary evolution characteristics. However, research on the original ore-forming parent fluid directly related to potash formation has not yet been carried out, directly hindering further evaluation of potash mineralization. Therefore, this paper takes the internal factors controlling potash formation as the starting point and analyzes the physical and chemical properties, such as the homogenization temperatures (

T

h

) and chemical compositions, of primary halite fluid inclusions. A total of 220

T

h

data from fluid inclusions were obtained, and the temperatures ranged from 9.4 to 54.1°C, indicating a high-temperature brine environment conducive to the rapid deposition of the potash deposit. In total, 22 halite fluid inclusions were analyzed for chemical components. The highest KCl content reached 0.59%, which was higher than the lowest industrial grade of potassium-rich brine (0.5%), indicating that the brine experienced a high degree of evaporation and concentration during the salt-forming period and reached the potash precipitation stage. This paper provides quantitative data on the evolution of the sedimentary environment in the Kuqa Basin and supports future potash exploration.
Optimizing Train Timetable Based on Departure Time Preference of Passengers for High-Speed Rails
Authors: Huang Zhipeng , Niu Huimin , Gao Ruhu , Fan Haoyu , Liu Chenglin
Published: March 2021

Passengers would like to choose the most suitable train based on their travel preferences, expenses, and train timetable in the high-speed railway corridor. Meanwhile, the railway department will constantly adjust the train timetable according to the distribution of passenger flows during a day to achieve the optimal operation cost and energy consumption saving plan. The question is how to meet the differential travel needs of passengers and achieve sustainable goals of service providers. Therefore, it is necessary to design a demand-oriented and environment-friendly high-speed railway timetable. This paper formulates the optimization of train timetable for a given high-speed railway corridor, which is based on the interests of both passengers and transportation department. In particular, a traveling time-space network with virtual departure arc is constructed to analyze generalized travel costs of passengers of each origin-destination (OD), and bilevel programming model is used to optimize the problem. The upper integer programming model regards the minimization of the operating cost, which is simplified to the minimum traveling time of total trains, as the goal. The lower level is a user equilibrium model which arranges each OD passenger flow to different trains. A general advanced metaheuristic algorithm embedded with the Frank–Wolfe method is designed to implement the bilevel programming model. Finally, a real-world numerical experiment is conducted to verify the effectiveness of both the model and the algorithm.
Evaluation and Transplantation of a SARS-CoV-2 Seropositive Kidney Candidate
Authors: Graves Maya C. , Mehta Sapna A. , Lonze Bonnie E. , Ali Nicole M.
Published: March 2021

The COVID-19 pandemic affected transplant center activity in areas with high number of cases such as New York City and prompted reevaluation of patients awaiting organ transplant diagnosed with SARS-CoV-2 infection. To resume safe transplantation at our center, we found it necessary to (1) identify transplant candidates with possible exposure to or history of COVID-19 infection, (2) outline a clinical and laboratory assessment to determine adequate clinical recovery from COVID-19 for transplantation, and (3) determine whether the possibility of perioperative COVID-19 transmission from the patient to staff would pose unacceptable risk. Here, we describe our center’s approach to proceeding with transplantation in a SARS-CoV-2 seropositive living donor kidney transplant recipient and describe early posttransplant outcomes.
Water‐Jet Erosion of Grade‐A Ship Steel: Experimental Research
Authors: Cao Yupeng , Zhang Yue , Shi Weidong , Lu Hua , Tan Linwei , Yang Yongfei
Published: March 2021

A water‐jet erosion test was carried out on grade‐A ship steel to study the interaction and erosion mechanism of the water jet on the steel surface. When the water jet impacted, a STSS‐1 stress‐detection module was used to collect the dynamic strain signal on the rear of the ship’s plate, and a scanning electron microscope, transmission electron microscope, X‐ray diffractometer, and other equipment were used to analyze the microstructure and phase of the grade‐A ship steel before impact. The surface morphology of the material after impact was studied and analyzed. The impact stress of the water jet on the grade‐A steel was an alternating stress, and the jet pressure decayed in the radial direction. The material surface was fatigued under the action of the jet alternating stress. After the water‐jet erosion, the central area of the grade‐A steel was dominated by an elongated cementite hard phase, and the peripheral area had a pearlite structure. A model for the jet erosion and peeling of grade‐A ship steel was established to clarify the mechanism of erosion by the water jet.
Thermal Diffusion Characteristics in Permafrost during the Exploitation of Gas Hydrate
Authors: Wei Yusen , Xiong Youming , Liu Zhiqiang , Lu Jingsheng
Published: March 2021

Methane hydrate is the vast potential resources of natural gas in the permafrost and marine areas. Due to the occurrence of phase transition, the gas hydrate is dissociated into gas and water and absorbs lots of heat. The incomprehensive knowledge of endothermic reaction in permafrost sediments still restricted the production efficiency of hydrate commercial development. This endothermic reaction leads to a complex thermal diffusion in permafrost, which directly influences the phase transition in turn. In this research, the heat during the exploitation is transferred in two forms (specific heat and latent heat). Besides, the melting point is not constant but depends on the pore size of the reservoir rock. According to these features, a thermal diffusion model with phase transition is established. To calculate the governing equation, the pore size distribution is obtained by using the nuclear magnetic resonance (NMR) method. The heating tests are conducted and simulated to calibrate the coefficient (i.e., transverse surface relaxivity) of NMR. Then, the temperature field evolution of the hydrate reservoir during the exploitation is simulated by using the calibrated values. The results show that the temperature curves have a typical plateau related to the pore size distribution, which is effective to obtain the surface relaxivity. The heat transfer is remarkably limited by the endothermic effect of the phase transition. The hydrate recovery efficiency may depend largely on the heating capacity of the engineering operation and the rate of gas production. Compared to the conventional petroleum industry, it is significant to control the maximum temperature and temperature distribution in engineering operations during hydrate development. This research on the temperature behavior during onshore permafrost hydrate production could provide the theoretical support to control heat behavior of offshore hydrate production.
Renal Replacement Modality Affects Uremic Toxins and Oxidative Stress
Authors: Niemczyk Longin , Malyszko Jolanta
Published: March 2021

Nowadays, the high prevalence of kidney diseases and their related complications, including endothelial dysfunction and cardiovascular disease, represents one of the leading causes of death in patients with chronic kidney diseases. Renal failure leads to accumulation of uremic toxins, which are the main cause of oxidative stress development. The renal replacement therapy appears to be the best way to lower uremic toxin levels in patients with end‐stage renal disease and reduce oxidative stress. At this moment, despite the increasing number of recognized toxins and their mechanisms of action, it is impossible to determine which of them are the most important and which cause the greatest complications. There are many different types of renal replacement therapy, but the best treatment has not been identified yet. Patients treated with diffusion methods have satisfactory clearance of small molecules, but the clearance of medium molecules appears to be insufficient, but treatment with convection methods cleans medium molecules better than small molecules. Hence, there is an urgent need of new more validated, appropriate, and reliable information not only on toxins and their role in metabolic disorders, including oxidative stress, but also on the best artificial renal replacement therapy to reduce complications and prolong the life of patients with chronic kidney disease.
An Intelligent Framework for Analyzing the Feasible Modes of Transportation in Metropolitan Cities: A Hybrid Multicriteria Approach
Authors: Srivastava Praveen Ranjan , Zhang Zuopeng (Justin) , Eachempati Prajwal , Lyu Hongbo
Published: March 2021

The paper aims to build a hybrid personalized multicriteria model in the Indian transportation industry to identify the most feasible transport mode suitable for commuters’ customized preferences. A hybrid multicriterion model, i.e., Fuzzy Analytical Hierarchy Process (AHP), was used to compute the criteria weights, which were subsequently analyzed by three approaches, namely, Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS), Fuzzy TOPSIS, Evaluation Based on Distance from Average Solution (EDA), and Interpretive Ranking Process (IRP). The case of an Indian metropolitan city, Hyderabad, is taken to illustrate the proposed approach. The paper highlights the following transport modes: metropolitan train (unconventional mode) and conventional modes such as the car, public bus transport, and bikes for Hyderabad. Furthermore, sensitivity analysis is performed to identify the consistency in ranking with variation in weights, and the Ensemble Ranking and transportation experts validate the rankings.
Effect of Surface Type on the Flow Characteristics in Shale Nanopores
Authors: Zhan Shiyuan , Su Yuliang , Lu Mingjing , Cai Mingyu , Fu Jingang , Liu Zupeng , Wang Kaiyu , Han Qi
Published: March 2021

The underlying mechanism of shale gas migration behavior is of great importance to understanding the flow behavior and the prediction of shale gas flux. The slippage of the methane molecules on the surface is generally emphasized in nanopores in most predicted methods currently. In this work, we use molecular dynamic (MD) simulations to study the methane flow behavior in organic (graphene) and inorganic (quartz) nanopores with various pore size. It is observed that the slippage is obvious only on the graphene nanopores and disappeared on the quartz surface. Compared with the traditional Navier-Stokes equation combined with the no-slip boundary, the enhancement of the gas flux is nonnegligible in the graphene nanopores and could be neglected in the quartz nanopores. In addition, the flux contribution ratios of the adsorption layer, Knudsen layer, and the bulk gas are analyzed. In quartz nanopores, the contributions of the adsorption layer and the Knudsen layer are slight when the pore size is larger than 10 nm. It is also noted that even if the Knudsen number is the same, the flow mode may be various with the effect of the pore surface type. Our work should give molecular insights into gas migration mechanisms in organic and inorganic nanopores and provide important reference to the prediction of the gas flow in various types of shale nanopores.
One-Pot, Surfactant-Free Synthesis of Gold Nanostars and Evaluation of Their Antibacterial Effects against Propionibacterium acnes
Authors: Huynh Phat Trong , Nguyen Giang Dang , Tran Khanh Thi Le , Ho Thu Minh , Duong Bich Thi , Lam Vinh Quang , Ngo Thanh Vo Ke
Published: March 2021

Anisotropic gold nanoparticles, especially gold nanostars, are used in many fields of biomedical applications such as sensing, targeted drug delivery, and diagnostic and photothermal therapy. In this study, we introduced a novel application of gold nanostars as an antimicrobial agent. While spherical gold nanoparticles have an inappreciable effect, gold nanostars exhibit significant antibacterial activity. Besides, the seed-mediated method, a conventional technique for preparing gold nanostars, is rather complex and toxic to human and environment due to unsafe synthesized materials such as surfactants and reducers. In recent years, green chemistry for nanoparticle synthesis is attractive because of its advantages. Instead of the seed-mediated procedure, we present a facile and green procedure to synthesize gold nanostars using ascorbic acid as a reductant and chitosan as a directing-growth agent. The influences of reacting parameters were evaluated to determine the optimal conditions. Star-shaped gold nanoparticles were successfully synthesized with average size tunning from

137.0
±
20.7
 
nm

to

281.9
±
25.8
 
nm

of the core and

14.0
±
4.4
 
nm

to

54.2
±
11.9
 
nm

of branches. Antibacterial activity against Propionibacterium acnes of gold nanostars was also investigated. Propionibacterium acnes is one of the main reasons causing acne vulgaris. The antibacterial test was evaluated by the plate count and well diffusion method. The results showed a significant effect that gold nanostars could be the prospective agent for replacing antibiotics in acne treatment.
Flexible Numerology in 5G NR: Interference Quantification and Proper Selection Depending on the Scenario
Authors: Flores de Valgas Josue , Monserrat Jose F. , Arslan Hüseyin
Published: March 2021

The 3rd Generation Partnership Project (3GPP) adopted cyclic prefix OFDM (CP-OFDM) for both uplink and downlink communications (although DFT-s-OFDM is also allowed in the uplink) in 5G New Radio (NR) Release 15. However, due to the variety of proposed deployment options and scenarios, a single numerology will not be enough to fulfil all performance requirements. A scalable OFDM numerology was required to enable diverse services on a wide range of frequencies and deployments, and finding the right numerology for each scenario is of special relevance for the proper functioning of 5G NR. Using a simulator calibrated according to the parameters established for NR performance by the 3GPP, this paper presents the performance evaluation of NR for the main 5G scenarios and different CP-OFDM numerologies and device speeds. Results show that increasing subcarrier spacing boosts the strength of the system against intercarrier interference (ICI) caused my Doppler spread; however, to increase subcarrier spacing, the CP must be reduced proportionally, which makes intersymbol interference (ISI) and ICI caused by insufficient CP have a more predominant effect. Therefore, it is necessary to quantify the total interference of the system, in order to determine the proper numerology for each scenario, which will depend on all the factors mentioned above, and not only on the operation band, as suggested in the standardization process. All this allows concluding that the choice of the appropriate numerology for a particular system depends not only on the band of operation but also on the deployment scenario and the speed of the user equipment (UE). Likewise, it is concluded that it is even possible to use more than one numerology for the same scenario.
An Influence Study of Face Length Effect on Floor Stability under Water-Rock Coupling Action
Authors: Fu Baojie , Wang Bo
Published: March 2021

The Taiyuan Formation limestone aquifer and Ordovician limestone aquifer are widely distributed in the coal seam floor of coal measures in North China; the water hazard safety problem of the stope floor under the influence of mining is very prominent. The risk of the water inrush from the coal seam floor is closely related to the degree of full exploitation, so it is necessary to study the stability of the stope floor under aquifer conditions, especially the influence of the working face length effect on floor stability. Through numerical simulation of water-rock coupling action, the mine pressure behaviors of the water-resisting floor under different face lengths were analyzed based on the measured formation permeability coefficient. The Fish program was used to adjust rocks entering the plastic failure state into a strain softening model to investigate the influence of the face length effect, the damage degree of the water-resisting floor, and the morphology and deformation bearing capacity of the failure zone. The results show the following: (1) the face length effect is one of the main influence factors of the failure mode and failure degree of surrounding rocks in the stope; (2) as the face length increases, the obvious pressure relief zone of surrounding rocks presents a staged change, and the obvious pressure relief zone at the seam roof and floor is in an obvious “reverse saddle shape”; (3) the closer to the seam floor, the more remarkable the rock softening characteristic because of the compaction action of gangues caving from the roof; and (4) the rock mass close to the seam floor undergoes local tensile failure, and the water-resisting floor near the coal wall at two sides mainly bears compaction-shear action, leading to compression-shear failure of the rock mass at the floor and formation of water-conducting fractures. The study results can provide a reference for taking precautionary measures of safety mining above a confined aquifer.
Analyzing Chinese Customers’ Switching Intention of Smartphone Brands: Integrating the Push-Pull-Mooring Framework
Authors: Guo Jin , Shan Shan , Wang Yu , Khan Yousaf Ali
Published: March 2021

With increasing technology advancement, online shopping, and growth of affordable segment, smartphone users’ switching behavior is becoming a concern for smartphone companies. To fill the research gap that persists in relation to the switching behavior of smartphone users from a multidimensional view, this study integrates the push-pull-mooring model to investigate and classify factors that affect the switching behavior of smartphone users. To test the hypotheses in relation to different predictors, data were collected from a survey of 246 users of the top ten smartphone brands in China and analyzed using structural model equation through regression analyses. The results revealed that the pull, push, and mooring factors have a significant impact on the switching behavior of smartphone users. While the pull effects have a stronger impact than push effects, the mooring factors were found to have a significant and strongest effect on smartphone users’ switching behavior. In particular, subjective norm showed the greatest impact on switching behavior, product quality and obsolete features showed significant and weak impact while brand image, switching cost, and poor customer service did not show any significant impact. These findings provide useful implications and insights for smartphone brands to develop competitive strategies for customer relationship management.
Neutron Transport Simulations of RBMK Fuel Assembly Using Multigroup and Continuous Energy Data Libraries within the SCALE Code
Authors: Slavickas Andrius , Pabarčius Raimondas , Tonkūnas Aurimas , Rimkevičius Sigitas
Published: March 2021

The neutron transport simulations of RBMK-1500 fuel assembly were performed using both multigroup and continuous energy data libraries available within the SCALE code system in order to validate its suitability for the estimation of RBMK neutronic characteristics. The resonance processing of cross section, involved in the preparation of the multigroup data library, has a significant impact on neutron transport calculations. Standard Dancoff factors (DFs) used for the heterogeneous geometry of RBMK fuel assembly are insufficient for the accurate estimation of resonance self-shielding. Thus, the SCALE module MCDancoff was used in this study to determine location-specific DFs. The results of RBMK-1500 fuel assembly simulations using standard and user-defined DFs were compared. In addition, the continuous energy (CE) cross-section data library was applied for the benchmark calculations. The impact of different nuclear data libraries on neutron transport simulations was tested as well. It was found out that the usage of the multigroup data libraries generates some deviation from the reference simulations obtained with CE libraries. The CE library based on the estimated ENDF/B-VII.1 data proved to be the best alternative for neutron transport simulations of RBMK fuel assembly.
Changes of Mineralogical Properties and Biological Activities of Gypsum and Its Calcined Products with Different Phase Structures
Authors: Liu Kaiyang , Han Shu , Gao Wei , Tang Ya’nan , Han Xitao , Liu Ziqin , Bao Liyuan , Zhi Meiru , Wang Hongyue , Wang Yingli , Du Hong
Published: March 2021

Raw gypsum (RG) and calcined gypsum (CG) are widely used in traditional Chinese medicine (TCM). RG is usually taken orally to resolve heat and diminish inflammation, while CG is only used externally to treat ulcerations and empyrosis. Calcination at different temperatures, three phase CG structures, namely, bassanite, anhydrite III, and anhydrite II, may be generated. We herein investigated the relationship between the phase structure and the efficacy of CG and the optimum phase structure for CG. RG has a compact structure, small pore size, weak anti-inflammatory effect, but no antibacterial effect, and has almost no effect on the repair of scalds. CG150 (bassanite) has a loose texture, large pore size and specific surface area, and certain antibacterial and anti-inflammatory effects, but it has a poor repair effect on scalds. CG750 (anhydrite II) has a compact structure, small pore size and specific surface area, and low antibacterial and anti-inflammatory effects, but it has a certain repair effect on scalds. Only CG350 (anhydrite III) has good performance in texture, pore size, specific surface area, antibacterial, anti-inflammatory, and scald repair. Our research has proved that the mineral properties and biological activities of CG are different due to different phase structures. CG350, namely, anhydrite III, is considered by our research to be the optimal phase structure as CG.
Virtual Screening of Cablin Patchouli Herb as a Treatment for Heat Stress: A Study Based on Network Pharmacology, Molecular Docking, and Experimental Verification
Authors: Xu Yan , Ding Lizhong , Wang Zhongtian , Wang Yanbo , Sun Liping
Published: March 2021

Heat-related diseases have long been known to damage the structure and function of essential macromolecules such as proteins, lipids, and nucleic acids, thereby compromising the integrity of cells and tissues and the physiological functions of the entire organism. Heat stress is the physical discomfort caused by overheating the body and is also the initial manifestation of heat-related diseases. Cablin patchouli herb (CPB) has been used in China for two thousand years and has been used to treat heat stress, but to date, no related mechanistic research is available. In this study, KEGG and PPI networks and the TCMSP and GEO databases were used to explore the components of CPB in relation to heat stress: quercetin, genkwanin, irisolidone, 3,23-dihydroxy-12-oleanen-28-oic acid, and quercetin 7-O-β-D-glucoside. The targets identified were EGFR, NCOA1, FOS, HIF1A, NFKBIA, and NCOA2; these proteins were verified by molecular docking and experimental verification. In short, our research represents the first report on the use of the traditional Chinese medicine CPB to treat heat stress and thus has pioneering significance.
Histomorphological Characteristics and Pathological Types of Hyperproliferation of Gastric Surface Epithelial Cells
Authors: Wang Yangkun , Shen Lan , Zhao Guang , Li Baohui , Bu Jianxue , Zhu Chaoya , Jiang Bo , Wang Sunan
Published: March 2021

Objective. To investigate the histomorphological characteristics and pathological types of hyperproliferation of gastric surface epithelial cells. Methods. Hematoxylin and Eosin, Periodic acid–Schiff, and immunohistochemical staining were performed on biopsy specimens obtained from 723 patients with hyperproliferation of gastric surface epithelial cells and/or hyperplasia of gastric pits. Follow-up gastroscopic reexaminations were performed on 475 patients included. Improvement probability was analyzed using Kaplan-Meyer as well as Cox proportional hazards models. Results. Seven different histomorphologies and clinicopathologies of hyperproliferation of gastric surface epithelial cells were identified: (1) common hyperplasia of gastric epithelial cells, which was characterized by focal glandular epithelial hyperplasia of gastric pits with chronic inflammation; (2) drug-induced hyperplasia of gastric epithelial cells, which was characterized by increased hyperplasia of gastric pits and cells arranged in a monolayer; (3) Helicobacter pylori (Hp) infection-induced hyperplasia of gastric epithelial cells, which was characterized by the disappearance of oval, spherical, and bounded membrane-enclosed mucus-containing granules in the cytoplasm and on the nucleus together with cytoplasmic swelling and vacuolation; (4) metaplastic hyperplasia of gastric epithelial cells, which was characterized by the coexistence of intestinal metaplastic cells with hyperplastic gastric epithelial cells; (5) atrophic hyperplasia of gastric epithelial cells, which was characterized by the mucosal atrophy accompanied with hyperplasia of gastric pits; (6) low-grade neoplasia of epithelial cells, which was characterized by the mild to moderate dysplasia of gastric epithelial cells; and (7) high-grade neoplasia of epithelial cells, which was characterized by the evident dysplasia of hyperplastic epithelial cells and losses of cell polarity. The different pathological types are associated with different improvement probabilities. Conclusions. This study demonstrated the histomorphological characteristics and pathological types, which might guide clinicians to track malignant cell transformation, perform precise treatment, predict the clinical prognosis, and control the development of gastric cancer.
Pulmonary Artery Filling Defects in COVID‐19 Patients Revealed Using CT Pulmonary Angiography: A Predictable Complication?
Authors: Scardapane Arnaldo , Villani Laura , Bavaro Davide Fiore , Passerini Francesca , Ianora Amato Antonio Stabile , Lucarelli Nicola Maria , Angarano Gioacchino , Portincasa Piero , Palmieri Vincenzo Ostilio , Saracino Annalisa
Published: March 2021

Purpose. This study is aimed at assessing the prevalence of pulmonary artery filling defects (PAFDs) consistent with pulmonary artery embolism (PAE) in patients with SARS‐CoV‐2 infection and at investigating possible radiological or clinical predictors. Materials and Methods. Computed Tomography Pulmonary Angiographies (CTPAs) from 43 consecutive patients with a confirmed COVID‐19 infection were retrospectively reviewed, taking into consideration the revised Geneva score and the D‐dimer value for each patient. Filling defects within the pulmonary arteries were recorded along with pleural and parenchymal findings such as ground glass opacities, consolidation, crazy paving, linear consolidation, and pleural effusion. All these variables were compared between patients with and without PAFD. The predictive performance of statistically different parameters was investigated using the receiver operating characteristics (ROC). Results. Pulmonary embolism was diagnosed in 15/43 patients (35%), whereas CTPA and parenchymal changes related to pulmonary COVID‐19 disease were evident in 39/43 patients (91%). The revised Geneva score and the mean D‐dimer value obtained using two consecutive measurements were significantly higher in patients with PAFD. The ROC analysis demonstrated that a mean D‐dimer value is the parameter with the higher predictivity (AUC 0.831) that is a cut‐off value > 1800 μg/l which predicts the probability of PAFD with a sensitivity and specificity of 70% and 78%, respectively. Conclusions. This single centre retrospective report shows a high prevalence of pulmonary artery filling defects revealed using CTPA in COVID‐19 patients and demonstrates that the mean value of multiple D‐dimer measurements may represent a predicting factor of this complication.
LSTM-Based Output-Constrained Adaptive Fault-Tolerant Control for Fixed-Wing UAV with High Dynamic Disturbances and Actuator Faults
Authors: Chang Xiaofei , Rong Lulu , Chen Kang , Fu Wenxing
Published: March 2021

The unknown disturbances and the changing uncertainties bring difficulties for designing a stable attitude controller for UAV. In this paper, a novel adaptive fault-tolerant attitude control approach is designed based on the long short-term memory (LSTM) network for the fixed-wing UAV subject to the high dynamic disturbances and actuator faults. Firstly, the high dynamic disturbances can be compensated by the adaptive laws. Meanwhile, the actuator faults can be handled by the proposed adaptive fault-tolerant control (AFTC) scheme. Moreover, the LSTM network is introduced to approximate the unknown and time-accumulating nonlinearities. With the introduction of the one-to-one nonlinear mapping (NM), the output constraints in the control system can be guaranteed. Additionally, it can be demonstrated that the boundness of all the signals can be assured. At last, numerical simulation results are provided to illustrate the effectiveness of the proposed method.