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Article ; Online: The Significance of Nanomineral Particles during the Growth Process of Polymetallic Nodules in the Western Pacific Ocean

Qiangtai Huang / Bo He / Zhourong Cai / Qianru Huang

International Journal of Environmental Research and Public Health, Vol 19, Iss 13972, p

2022 Volume 13972

Abstract: As a huge reservoir of economic metallic elements, oceanic polymetallic nodules have important strategic significance and are one of the main research objects in marine geology, especially their formation process and genetic mechanism. In this study, ... ...

Abstract	As a huge reservoir of economic metallic elements, oceanic polymetallic nodules have important strategic significance and are one of the main research objects in marine geology, especially their formation process and genetic mechanism. In this study, polymetallic nodules from the cobalt-rich crust exploration contract area in the Western Pacific Ocean were taken as the research object. Optical microscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy dispersive spectroscopy (EDS) were used for observation and testing. The results indicate that many nanomineral particles, mainly composed of Fe and Mn, developed in polymetallic nodules from the western Pacific Ocean. The solid–liquid interface process of nanomineral particles plays an important role in the growth and evolution of nodules. We propose that the growth process of polymetallic nodules in the western Pacific Ocean can be divided into three stages. First, terrigenous detritus nucleates, and nanomineral particles composed of Fe, Mn, and other elements form, aggregate and attach to the core to form the initial shell. Second, a dense layer of the shell forms under stable conditions. In the third stage, the redox conditions of the nodules change, and the polymetallic nodules experience a variety of interface process modifications.
Keywords	polymetallic nodules ; nanomineral particles ; growth process ; Western Pacific Ocean ; Medicine ; R
Subject code	551
Language	English
Publishing date	2022-10-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Research on the Impact Force of Rockfall Impacting Sand Cushions with Different Shapes

Yu Zhang / Lingzhi Xie / Bo He / Peng Zhao

Applied Sciences, Vol 12, Iss 3540, p

2022 Volume 3540

Abstract: Shed structures are an important engineering method for mountain highways to resist rockfall impacts. Research on the rockfall impact response is very important to the design of rockfall disaster protection structures to shed cave structures. To explore ... ...

Abstract	Shed structures are an important engineering method for mountain highways to resist rockfall impacts. Research on the rockfall impact response is very important to the design of rockfall disaster protection structures to shed cave structures. To explore the impact difference caused by different rockfall shapes, five mortar ellipsoids were fabricated with different shapes by 3D printing the falling stone mould. Laboratory experiments were carried out to study the impact effect of five different shapes of falling stones on the sand cushion. Different shapes of rockfall correspond to different impact forces. The tip ellipsoid (D1 and D2) is the smallest, the sphere (D3) is the second, and the flat ellipsoid (D4 and D5) is the largest. The fitting analysis of the impact force results of the laboratory experiment showed that the impact of the falling height on the impact force was relatively independent and did not change with the shape of the falling rock. Then, based on the impact force of the sphere falling rock, a calculation formula of the impact force with the introduction of the shape factor was obtained, and it was compared and verified with the test results from other studies. To study the applicability of the formula in the actual engineering scale, a numerical model was established by ANSYS. After verifying the reliability of the numerical model, the impact process of a large energy level was simulated. According to the simulation results, the rationality of the formula proposed in this paper is further verified, which guides the actual rockfall impact prevention and control engineering.
Keywords	rockfall impact ; rockfall shape ; impact force ; falling height ; numerical simulation ; Technology ; T ; Engineering (General). Civil engineering (General) ; TA1-2040 ; Biology (General) ; QH301-705.5 ; Physics ; QC1-999 ; Chemistry ; QD1-999
Subject code	306
Language	English
Publishing date	2022-03-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Numerical Study on the Use of Alternating Injection Hydraulic Fracturing Technology to Optimize the Interaction Between Hydraulic Fracture and Natural Fracture

Yang Yang / Lingzhi Xie / Bo He / Peng Zhao

Frontiers in Earth Science, Vol

2022 Volume 10

Abstract: Hydraulic fracturing is a key technology for shale gas production. Activating the natural fracture (NF) system in shale reservoirs and forming a complex fracture network can greatly improve the effect of fracturing. The effect of fracturing is mainly ... ...

Abstract	Hydraulic fracturing is a key technology for shale gas production. Activating the natural fracture (NF) system in shale reservoirs and forming a complex fracture network can greatly improve the effect of fracturing. The effect of fracturing is mainly influenced by geological factors and operational parameters of a reservoir. Effectively reforming a reservoir under unfavourable geological conditions and maximizing the activation of NFs in the reservoir can substantially increase its reformed volume and the production of shale gas. Alternating fluid injection (AFI) fracturing technologies using multiple fracturing fluids with different viscosities can activate closed NFs while retaining the high conductivity of the principal fracture to achieve a larger stimulated reservoir volume (SRV). In this paper, a hydraulic-mechanical coupling finite element method (FEM) of a reservoir is established, and AFI fracturing technology is numerically simulated using the continuum method. In addition, the fracture propagation stage and path propagation for AFI technology are discussed. The results show that AFI fracturing technology can form principal fractures with high conductivity and activate NFs in a reservoir to form comparatively complex fracture propagation paths.
Keywords	hydraulic fracturing ; finite element method ; alternating fluid injection ; shale gas ; natural fracture ; Science ; Q
Subject code	550
Language	English
Publishing date	2022-03-01T00:00:00Z
Publisher	Frontiers Media S.A.
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: R -α-Lipoic Acid and 4-Phenylbutyric Acid Have Distinct Hypolipidemic Mechanisms in Hepatic Cells

Bo He / Régis Moreau

Biomedicines, Vol 8, Iss 289, p

2020 Volume 289

Abstract: The constitutive activation of the mechanistic target of rapamycin complex 1 (mTORC1) leads to the overproduction of apoB-containing triacylglycerol-rich lipoproteins in HepG2 cells. R -α-lipoic acid (LA) and 4-phenylbutyric acid (PBA) have hypolipidemic ...

Abstract	The constitutive activation of the mechanistic target of rapamycin complex 1 (mTORC1) leads to the overproduction of apoB-containing triacylglycerol-rich lipoproteins in HepG2 cells. R -α-lipoic acid (LA) and 4-phenylbutyric acid (PBA) have hypolipidemic function but their mechanisms of action are not well understood. Here, we reported that LA and PBA regulate hepatocellular lipid metabolism via distinct mechanisms. The use of SQ22536, an inhibitor of adenylyl cyclase, revealed cAMP’s involvement in the upregulation of CPT1A expression by LA but not by PBA. LA decreased the secretion of proprotein convertase subtilisin/kexin type 9 (PCSK9) in the culture media of hepatic cells and increased the abundance of LDL receptor (LDLR) in cellular extracts in part through transcriptional upregulation. Although PBA induced LDLR gene expression, it did not translate into more LDLR proteins. PBA regulated cellular lipid homeostasis through the induction of CPT1A and INSIG2 expression via an epigenetic mechanism involving the acetylation of histone H3, histone H4, and CBP-p300 at the CPT1A and INSIG2 promoters.
Keywords	thioctic acid ; butyrate ; hyperlipidemia ; dyslipidemia ; triacylglycerides ; cAMP ; Biology (General) ; QH301-705.5
Subject code	570
Language	English
Publishing date	2020-08-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: The Progress towards Novel Herbicide Modes of Action and Targeted Herbicide Development

Bo He / Yanhao Hu / Wen Wang / Wei Yan / Yonghao Ye

Agronomy, Vol 12, Iss 2792, p

2022 Volume 2792

Abstract: To date, effectively controlling resistant weeds has been a great challenge in modern agricultural production. Developing new modes of action of herbicides would be an efficient, convenient, and timely means of controlling resistant weeds. In particular, ...

Abstract	To date, effectively controlling resistant weeds has been a great challenge in modern agricultural production. Developing new modes of action of herbicides would be an efficient, convenient, and timely means of controlling resistant weeds. In particular, new modes of herbicide action do not appear to have evolutionary resistance or cross-resistance with existing herbicides. However, a few successful herbicides with new modes of action (MoAs) have been marketed in the past 20 years. In this paper, we analyzed limiting factors for the slow development of novel herbicide MoAs. We then summarized the positive herbicide targets for the herbicides that have been discovered in recent years, such as Solanyl Diphosphate Synthase (SPS), Fatty Acid Thioesterase (FAT), Plastid Peptide Deformylase (PDEF), and Dihydroxy-Acid Dehydratase (DHAD). Some commercial herbicide varieties have been obtained based on novel herbicide targets, such as Homogentisate Solanesyltransferase (HST) and Dihydroorotate Dehydrogenase (DHODH). This provides a new reference and idea for herbicide molecular design in the future. In addition, some practical and efficient methods were mentioned for the rational design, discovery, and development of targeted herbicides development. In order to overcome the adverse conditions of compound druggability, prodrug strategies are also used in herbicide development, which can optimize the administration, permeability, absorption, and distribution of the original drug molecule or a candidate compound and may provide more possibilities for the development of new herbicides. The development of new herbicides is fascinating, the challenges and rewards are great, and the path to success is becoming more apparent.
Keywords	herbicide target ; mode of action (MoA) ; resistant weeds control ; targeted herbicide discovery and development ; Agriculture ; S
Subject code	630
Language	English
Publishing date	2022-11-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Spatial Pattern and Fairness Measurement of Educational Resources in Primary and Middle Schools

Wei Lu / Yuechen Li / Rongkun Zhao / Bo He / Zihua Qian

International Journal of Environmental Research and Public Health, Vol 19, Iss 10840, p

A Case Study of Chengdu–Chongqing Economic Circle

2022 Volume 10840

Abstract: China’s education has developed rapidly in recent years, but the issue of educational equality still exists. Currently, there are few studies on educational resources, and their spatial pattern and fairness remain unclear. Thus, this study selected the ... ...

Abstract	China’s education has developed rapidly in recent years, but the issue of educational equality still exists. Currently, there are few studies on educational resources, and their spatial pattern and fairness remain unclear. Thus, this study selected the point of interest data and spatial analysis methods to depict the spatial pattern of educational resources (containing the number of teachers, students, facilities, etc.). Then, we evaluated the equity of educational resources (including the number of schools and school teachers) in terms of geographic and population distribution by combining statistical yearbook data with two indices (the index of dissimilarity and agglomeration degree) to promote healthy urban development. The results show the following. (1) Educational resources have a multicenter spatial structure of “dual cores and multiple sub-centers”. The Moran index reflects a weak positive spatial correlation between educational resources. (2) The index of dissimilarity is between 0.02 and 0.21, which shows that the allocation of resources is relatively balanced. Regarding internal units, obvious differences exist in the agglomeration degree and equilibrium of educational resources.
Keywords	point of interest ; educational resources of primary and middle schools ; spatial pattern ; educational equality ; Chengdu–Chongqing economic circle ; Medicine ; R
Subject code	910
Language	English
Publishing date	2022-08-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Diapause-Linked Gene Expression Pattern and Related Candidate Duplicated Genes of the Mountain Butterfly Parnassius glacialis (Lepidoptera

Chengyong Su / Chen Ding / Youjie Zhao / Bo He / Ruie Nie / Jiasheng Hao

International Journal of Molecular Sciences, Vol 24, Iss 5577, p

Papilionidae) Revealed by Comprehensive Transcriptome Profiling

2023 Volume 5577

Abstract: The mountain butterfly Parnassius glacialis is a representative species of the genus Parnassius, which probably originated in the high-altitude Qinhai–Tibet Plateau in the Miocene and later dispersed eastward into relatively low-altitude regions of ... ...

Abstract	The mountain butterfly Parnassius glacialis is a representative species of the genus Parnassius, which probably originated in the high-altitude Qinhai–Tibet Plateau in the Miocene and later dispersed eastward into relatively low-altitude regions of central to eastern China. However, little is known about the molecular mechanisms underlying the long-term evolutionary adaptation to heterogeneous environmental conditions of this butterfly species. In this study, we obtained the high-throughput RNA-Seq data from twenty-four adult individuals in eight localities, covering nearly all known distributional areas in China, and firstly identified the diapause-linked gene expression pattern that is likely to correlate with local adaptation in adult P. glacialis populations. Secondly, we found a series of pathways responsible for hormone biosynthesis, energy metabolism and immune defense that also exhibited unique enrichment patterns in each group that are probably related to habitat-specific adaptability. Furthermore, we also identified a suite of duplicated genes (including two transposable elements) that are mostly co-expressed to promote the plastic responses to different environmental conditions. Together, these findings can help us to better understand this species’ successful colonization to distinct geographic areas from the western to eastern areas of China, and also provide us with some insights into the evolution of diapause in mountain Parnassius butterfly species.
Keywords	Transcriptome ; Parnassius glacialis ; diapause ; environmental adaptation ; genome ; Biology (General) ; QH301-705.5 ; Chemistry ; QD1-999
Subject code	580 ; 590
Language	English
Publishing date	2023-03-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Unique regulatory roles of ncRNAs changed by PM2.5 in human diseases

Bo He / Hai-Ming Xu / Hao-Wen Liu / Yin-Feng Zhang

Ecotoxicology and Environmental Safety, Vol 255, Iss , Pp 114812- (2023)

2023

Abstract: PM2.5 is a type of particulate matter with an aerodynamic diameter smaller than 2.5 µm, and exposure to PM2.5 can adversely damage human health. PM2.5 may impair health through oxidative stress, inflammatory reactions, immune function alterations and ... ...

Abstract	PM2.5 is a type of particulate matter with an aerodynamic diameter smaller than 2.5 µm, and exposure to PM2.5 can adversely damage human health. PM2.5 may impair health through oxidative stress, inflammatory reactions, immune function alterations and chromosome or DNA damage. Through increasing in-depth studies, researchers have found that noncoding RNAs (ncRNAs), particularly microRNAs (miRNAs), circular RNAs (circRNAs) as well as long noncoding RNAs (lncRNAs), might play significant roles in PM2.5-related human diseases via some of the abovementioned mechanisms. Therefore, in this review, we mainly discuss the regulatory function of ncRNAs altered by PM2.5 in human diseases and summarize the potential molecular mechanisms. The findings reveal that these ncRNAs might induce or promote diseases via inflammation, the oxidative stress response, cell autophagy, apoptosis, cell junction damage, altered cell proliferation, malignant cell transformation, disruption of synaptic function and abnormalities in the differentiation and status of immune cells. Moreover, according to a bioinformatics analysis, the altered expression of potential genes caused by these ncRNAs might be related to the development of some human diseases. Furthermore, some ncRNAs, including lncRNAs, miRNAs and circRNAs, or processes in which they are involved may be used as biomarkers for relevant diseases and potential targets to prevent these diseases. Additionally, we performed a meta-analysis to identify more promising diagnostic ncRNAs as biomarkers for related diseases.
Keywords	Ambient particulate matter ; LncRNA ; MiRNA ; CircRNA ; Biomarker ; Diagnosis ; Environmental pollution ; TD172-193.5 ; Environmental sciences ; GE1-350
Subject code	610 ; 500
Language	English
Publishing date	2023-04-01T00:00:00Z
Publisher	Elsevier
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Investigation on the Impact of Trailing Edge Stacking Styles on Hydraulic Performance in the Multistage Submersible Pump Space Diffuser

Hui Zhang / Puyu Cao / Dan Ni / Xuran Gong / Bo He / Rui Zhu

Processes, Vol 11, Iss 12, p

2023 Volume 3358

Abstract: To investigate the effect of the different wrap angles from the hub to the shroud surface in the space diffuser (i.e., the trailing edge stacking style) on the principle of corner separation vortex flow, a numerical simulation method has been conducted ... ...

Abstract	To investigate the effect of the different wrap angles from the hub to the shroud surface in the space diffuser (i.e., the trailing edge stacking style) on the principle of corner separation vortex flow, a numerical simulation method has been conducted in a multistage submersible pump. Building a linear equation on the profile line of the diffuser trailing edge to optimize the wrap angle on every spanwise from the hub to the shroud, and the mapping response relationship between the wrap angle difference and the hydraulic performance in the space diffuser has been analyzed. Under the variable wrap angle difference ( <semantics> Δ ϕ = ϕ h u b − ϕ s h r o u d </semantics> ), the secondary flows in different directions, non-uniformity, diffuser efficiency, and pressure recovery are compared. The positive wrap angle difference (i.e., the shroud wrap angle is smaller than the hub one) improves the strength of the secondary flow and partly corner separation vortex in the diffuser, so the hydraulic characteristic of positive cases is better than the negative wrap angle difference. Moreover, in scheme A (in which the hub wrap angle is constant and the shroud wrap angle decreasing), the transversal secondary flow has been weakened, the low-energy fluid located in the corner has been suppressed, the extensional secondary flow has been increased, the diffuser hydraulic performance has been improved, and unidirectionally increases with the wrap angle difference increasing. When the shroud wrap angle is constant, the extensional secondary flow has been enhanced by the increasing hub wrap angle. Meanwhile, the increasing extensional secondary flow has been countered by the deteriorating extensional flow at the diffuser inlet and transversal secondary flow, the diffuser hydraulic performance increases and then decreases as the wrap angle difference increases, with an optimal wrap angle difference is about 20°.
Keywords	space diffuser ; trailing edge ; stacking styles ; wrap angle ; optimization method ; Chemical technology ; TP1-1185 ; Chemistry ; QD1-999
Subject code	621
Language	English
Publishing date	2023-12-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: A Generalized Alternating Linearization Bundle Method for Structured Convex Optimization with Inexact First-Order Oracles

Chunming Tang / Yanni Li / Xiaoxia Dong / Bo He

Algorithms, Vol 13, Iss 91, p

2020 Volume 91

Abstract: In this paper, we consider a class of structured optimization problems whose objective function is the summation of two convex functions: f and h , which are not necessarily differentiable. We focus particularly on the case where the function f is ... ...

Abstract	In this paper, we consider a class of structured optimization problems whose objective function is the summation of two convex functions: f and h , which are not necessarily differentiable. We focus particularly on the case where the function f is general and its exact first-order information (function value and subgradient) may be difficult to obtain, while the function h is relatively simple. We propose a generalized alternating linearization bundle method for solving this class of problems, which can handle inexact first-order information of on-demand accuracy. The inexact information can be very general, which covers various oracles, such as inexact, partially inexact and asymptotically exact oracles, and so forth. At each iteration, the algorithm solves two interrelated subproblems: one aims to find the proximal point of the polyhedron model of f plus the linearization of h the other aims to find the proximal point of the linearization of f plus h . We establish global convergence of the algorithm under different types of inexactness. Finally, some preliminary numerical results on a set of two-stage stochastic linear programming problems show that our method is very encouraging.
Keywords	nonsmooth convex optimization ; bundle method ; alternating linearization ; on-demand accurary ; global convergence ; Industrial engineering. Management engineering ; T55.4-60.8 ; Electronic computers. Computer science ; QA75.5-76.95
Subject code	510
Language	English
Publishing date	2020-04-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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