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Measurements and estimation of flow velocity in mobile bed rills

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International Journal of Sediment Research 2023年第1期38卷 97-104页

作者： Yunyun ban China Agricultural University Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

Rills are primary sediment sources and hillslope water/sediment runoff transport channels. Water flow velocities in rills are easily affected by bed condition over eroding and non-eroding slopes, which is an important hydrodynamic process in soil erosion research. This research is done to demonstrate the poorly understood “feedback mechanism” related to slope independence of flow velocity to slope gradient. A series of experiments were done on silt loam soil slopes to measure water flow velocity in rills under nine unit width flow rates(q)(0.17 × 10-3, 0.33 × 10-3, 0.67 × 10-3, 1.33 × 10-3, 2.67 × 10-3,5.33 × 10-3, 10.67 × 10-3, 21.33 × 10-3, and 42.67 × 10-3m3/(s·m)) combined with four slope gradients(8.7%, 17.6%, 26.8%, and 36.4%), in which mobile bed rills were monitored. For unit flow velocity under q ≤ 1.33 × 10-3m2/s, independence of flow velocity to slope was obtained. However, the results indicated that slope gradient combined with a higher unit flow rate contributed to better velocity prediction and fitted with a segmented equation well(R2= 0.95). A feedback mechanism was able to verify that the increase in roughness directly dissipated flow energy to reduce flow velocity, but cannot completely counterbalances steep slope effect. The experimental results showed that erosion-caused morphological changes on soil slopes reduce flow velocity by half due to an increase in bed roughness. Therefore, the current experimental measurements considering a wide range of flow rate and slope gradient conditions is useful to reveal the steep slope effect in mobile bed rills. The analysis showed that, for the investigated conditions, the flow velocity is a slope gradient-and flow ratedependent parameter.

关键词： Flow velocity Flow rate Slope gradient Model fitting Slope morphology

Implication and challenges of direct-fed microbial supplementation to improve ruminant production and health

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Journal of Animal Science and Biotechnology 2022年第2期13卷 316-337页

作者： Yajing ban Le Luo Guan Department of Agricultural Food and Nutritional ScienceUniversity of AlbertaEdmontonAlberta T6G 2P5Canada

Direct-fed microbials(DFMs)are feed additives containing live naturally existing microbes that can benefit animals’health and production performance.Due to the banned or strictly limited prophylactic and growth promoting usage of antibiotics,DFMs have been considered as one of antimicrobial alternatives in livestock industry.Microorganisms used as DFMs for ruminants usually consist of bacteria including lactic acid producing bacteria,lactic acid utilizing bacteria and other bacterial groups,and fungi containing Saccharomyces and Aspergillus.To date,the available DFMs for ruminants have been largely based on their effects on improving the feed efficiency and ruminant productivity through enhancing the rumen function such as stabilizing ruminal pH,promoting ruminal fermentation and feed digestion.Recent research has shown emerging evidence that the DFMs may improve performance and health in young ruminants,however,these positive outcomes were not consistent among studies and the modes of action have not been clearly defined.This review summarizes the DFM studies conducted in ruminants in the last decade,aiming to provide the new knowledge on DFM supplementation strategies for various ruminant production stages,and to identify what are the potential barriers and challenges for current ruminant industry to adopt the DFMs.Overall literature research indicates that DFMs have the potential to mitigate ruminal acidosis,improve immune response and gut health,increase productivity(growth and milk production),and reduce methane emissions or fecal shedding of pathogens.More research is needed to explore the mode of action of specific DFMs in the gut of ruminants,and the optimal supplementation strategies to promote the development and efficiency of DFM products for ruminants.

关键词： DFM-microbial interaction Direct-fed microbials Gut health Host-DFM interaction Ruminants

Monodelphis domestica: a new source of mammalian primary neurons in vitro

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Neural Regeneration Research 2022年第8期17卷 1726-1727页

作者： Jelena ban Miranda Mladinic Laboratory for Molecular Neurobiology Department of BiotechnologyUniversity of RijekaRijekaCroatia

In vi t ro mode ls have tremendously revolutionized cell biology and biomedical research,reducing the need for in vivo experiments,as well as offering the simplified models for easier investigations at molecular and cellular level(for example genetic manipulations,electrophysiological measurements,drug screening etc.).However,the major challenge is to develop long-surviving in vitro preparations of post-mitotic cells such as neurons or cardiocytes.To overcome the problem of neuronal inability to proliferate,the immortalized cell lines derived from neuronal tumors have been prepared.Such secondary neuronal cultures are restricted to neuroblastoma-like cells,but their biological relevance is often questionable due to genetic drift and lack of mature,differentiated neuronal phenotypes,which makes primary cultures the better choice.Mammalian central nervous system(CNS)in vitro primary cell cultures are mostly prepared from the late embryonic or early postnatal mice and rats.Other mammalian species have been less used,meaning that inter-species diversity is not sufficiently investigated and that the additional comparative analyses are required to avoid misinterpretations in translating the knowledge to humans(Bonfanti and Peretto,2011).

关键词： overcome offering mostly

Expression of Osteopontin and caudal-related homeobox gene 2:indications of phenotypes and prognosis in advanced gastric cancer

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福州总医院学报 2010年第4期17卷 212-217页

作者： Xia Zhang Tetsuya Tsukamoto Tsutomu Mizoshita ban hisayo Toyoda Takeshi Masae Tatematsu Division of Oncological Pathology Aichi Cancer Center Research Institute 1 - 1Kanokoden Chikusa-ku Nagoya Aichi 464-8681 Japan. Oncology department of Nanjing Command Fuzhou general hospital xi＇ er huan - lu156 Fuzhou 86-350025 China

Objective:To investigate the expression of osteopontin(OPN)and caudal-related homeobox gene 2(CDX2)in advanced gastric cancer,and to correlate them with clinicopathological features.Method:One-hundred and nine patients suffered from gastric cancer recruited.Expression of OPN and CDX2 and other molecular markers were determined using immunohistochemistry method.Results:Total positive rate of OPN expression was 46.79%,and related with depth of cancer invasion and different phenotype(P<0.001),no association with the patient's age,gender,tumor histological type and lymph node metastasis.In different phenotypes of gastric cancers,OPN frequently expressed in CDX2-negative-expressed G and N type(16/109 and 21/109,respectively),and in CDX2-positive-expressed GI and I types expression level were lower.OPN expression reversely correlated with cdx-2 expression(P<0.001).Patients with OPN positive expression had worse 5-year survival,and patients with OPN negative,5-year survival time better(P<0.001).Further analysis revealed patients with OPN-/CDX2+ had better 5-year survival than other three groups including OPN+/CDX2-,OPN-/CDX2-and OPN+/CDX2+.With multivariate analysis for 5-year survival,it suggested that OPN was the most significant predictor of poor prognosis in gastric cancer(P =0.0043),with lymph node metastasis and tumor depth of invasion were also independent indicators(P =0.0359 and P =0.0315,respectively).Conclusion:Osteopontin is a useful prognostic marker in gastric cancer,and combined with CDX2,it may be much more useful for predicting the survival time in advanced gastric cancer patients.Furthermore it also gave us a clue that in gastric cancer,CDX2 may be a transcription factor modulating the expression of osteopontin.

关键词：胃癌肿瘤症状临床分析

Identification of two QTLs associated with high fruit acidity in apple using pooled genome sequencing analysis

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Horticulture Research 2020年第1期7卷 560-573页

作者： Seunghyun ban Kenong Xu Horticulture Section School of Integrative Plant ScienceCornell AgritechCornell UniversityGenevaNY 14456USA

Acidity is a critical component determining apple fruit quality.Previous studies reported two major acidity quantitative trait loci(QTLs)on linkage groups(LGs)16(Ma)and 8(Ma3),respectively,and their homozygous genotypes mama and ma3ma3 usually confer low titratable acidity(TA)(10mgml^(−1))acidity levels.To date,the genetic control for high-acidity apples remains essentially unknown.In order to map QTLs associated with high acidity,two genomic DNA pools,one for high acidity and the other for regular acidity,were created in an interspecific F1 population Royal Gala(Malus domestica)×PI 613988(M.sieversii)of 191 fruit-bearing progenies.By Illumina paired-end sequencing of the high and regular acidity pools,1,261,640 single-nucleotide variants(SNVs)commonly present in both pools were detected.Using allele frequency directional difference and density(AFDDD)mapping approach,one region on chromosome 4 and another on chromosome 6 were identified to be putatively associated with high acidity,and were named Ma6 and Ma4,respectively.Trait association analysis of DNA markers independently developed from the Ma6 and Ma4 regions confirmed the mapping of Ma6 and Ma4.In the background of MaMa,20.6%of acidity variation could be explained by Ma6,28.5%by Ma4,and 50.7%by the combination of both.The effects of Ma6 and Ma4 in the background of Mama were also significant,but lower.These findings provide important genetic insight into high acidity in apple.

关键词： fir acidity analysis

A consecutive joint shear strength model considering the 3D roughness of real contact joint surface

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International Journal of Mining Science and Technology 2023年第5期33卷 617-624页

作者： Liren ban Zhigang Tao Weisheng Du Yuhang Hou School of Civil and Transportation Engineering Beijing University of Civil Engineering and ArchitectureBeijing 100044China State Key Laboratory of Deep Geotechnical Mechanics and Deep Underground Engineering Beijing 100083China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China School of Mechanics and Civil Engineering China University of Mining and TechnologyBeijing 100083China Deep Mining and Rock Burst Research Branch China Coal Research InstituteBeijing 100013China State Key Laboratory of Hydroscience and Engineering Tsinghua UniversityBeijing 100084China

A consecutive joint shear strength model for soft rock joints is proposed in this paper,which takes into account the degradation law of the actual contact three-dimensional(3D)roughness.The essence of the degradation of the maximum possible dilation angle is the degradation of the 3D average equivalent dip angle of the actual contact joint asperities.Firstly,models for calculating the maximum possible dilation angle at the initial and residual shear stress stages are proposed by analyzing the 3D joint morphology characteristics of the corresponding shear stages.Secondly,the variation law of the maximum possible dilation angle is quantified by studying the degradation law of the joint micro convex body.Based on the variation law of the maximum possible dilation angle,the maximum possible shear strength model is proposed.Furthermore,a method to calculate the shear stiffness degradation in the plastic stage is proposed.According to the maximum possible shear strength of rock joints,the shear stress-shear displacement prediction model of rock joints is obtained.The new model reveals that there is a close relationship between joint shear strength and actual contact joint roughness,and the degradation of shear strength after the peak is due to the degradation of actual contact joint roughness.

关键词： Shear strength Actual contact area 3D roughness Shear test

Connected Vehicle-Based Traffic Signal Coordination

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Engineering 2020年第12期6卷 1463-1472页

作者： Wan Li Xuegang ban Oak Ridge National Laboratory KnoxvilleTN 37932USA University of Washington SeattleWA 98195USA

This study presents a connected vehicles(CVs)-based traffic signal optimization framework for a coordinated arterial corridor.The signal optimization and coordination problem are first formulated in a centralized scheme as a mixed-integer nonlinear program(MINLP).The optimal phase durations and offsets are solved together by minimizing fuel consumption and travel time considering an individual vehicle’s trajectories.Due to the complexity of the model,we decompose the problem into two levels:an intersection level to optimize phase durations using dynamic programming(DP),and a corridor level to optimize the offsets of all intersections.In order to solve the two-level model,a prediction-based solution technique is developed.The proposed models are tested using traffic simulation under various scenarios.Compared with the traditional actuated signal timing and coordination plan,the signal timing plans generated by solving the MINLP and the two-level model can reasonably improve the signal control performance.When considering varies vehicle types under high demand levels,the proposed two-level model reduced the total system cost by 3.8%comparing to baseline actuated plan.MINLP reduced the system cost by 5.9%.It also suggested that coordination scheme was beneficial to corridors with relatively high demand levels.For intersections with major and minor street,coordination conducted for major street had little impacts on the vehicles at the minor street.

关键词： Connected vehicles Traffic signal coordination Dynamic programming Two-level optimization Mixed-integer nonlinear program

Metal-Organic Framework Membranes and Membrane Reactors:Versatile Separations and Intensified Processes

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Research 2020年第1期2020卷 122-134页

作者： Yujie ban Na Cao Weishen Yang State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of Sciences457 Zhongshan RoadDalian 116023China University of Chinese Academy of Sciences 19A Yuquan RoadBeijing 100039China

Metal-organic frameworks are an emerging and fascinating category of porous solids that can be self-assembled with metal-based cations linked by organic molecules.The unique features of MOFs in porosity(or surface areas),together with their diversity for chemical components and architectures,make MOFs attractive candidates in many applications.MOF membranes represent a long-term endeavor to convert MOF crystals in the lab to potentially industry-available commodities,which,as a promising alternative to distillation,provide a bright future for energy-efficient separation technologies closely related with chemicals,the environment,and energy.The membrane reactor shows a typical intensified process strategy by combining the catalytic reaction with the membrane separation in one unit.This review highlights the recent process of MOF-based membranes and the importance of MOF-based membrane reactors in relative intensified chemical processes.

关键词： separation distillation attractive

Augmenting Android Malware Using Conditional Variational Autoencoder for the Malware Family Classification

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Computer Systems Science & Engineering 2023年第8期46卷 2215-2230页

作者： Younghoon ban Jeong Hyun Yi Haehyun Cho Soongsil University Seoul06978Korea

Android malware has evolved in various forms such as adware that continuously exposes advertisements,banking malware designed to access users’online banking accounts,and Short Message Service(SMS)malware that uses a Command&Control(C&C)server to send malicious SMS,intercept SMS,and steal data.By using many malicious strategies,the number of malware is steadily increasing.Increasing Android malware threats numerous users,and thus,it is necessary to detect malware quickly and accurately.Each malware has distinguishable characteristics based on its actions.Therefore,security researchers have tried to categorize malware based on their behaviors by conducting the familial analysis which can help analysists to reduce the time and cost for analyzing malware.However,those studies algorithms typically used imbalanced,well-labeled open-source dataset,and thus,it is very difficult to classify some malware families which only have a few number of malware.To overcome this challenge,previous data augmentation studies augmented data by visualizing malicious codes and used them for malware analysis.However,visualization of malware can result in misclassifications because the behavior information of the malware could be compromised.In this study,we propose an android malware familial analysis system based on a data augmentation method that preserves malware behaviors to create an effective multi-class classifier for malware family analysis.To this end,we analyze malware and use Application Programming Interface(APIs)and permissions that can reflect the behavior of malware as features.By using these features,we augment malware dataset to enable effective malware detection while preserving original malicious behaviors.Our evaluation results demonstrate that,when a model is created by using only the augmented data,a macro-F1 score of 0.65 and accuracy of 0.63%.On the other hand,when the augmented data and original malware are used together,the evaluation results show that a macro-F1 score of 0.91 and an accuracy of 0.99%.

关键词： Android data augmentation artificial intelligence cybersecurity