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One of the fundamental parts of Geometric Function Theory is the study of analytic functions in different domains with critical geometrical interpretations. This article defines a new generalized domain obtained based on the quotient of two analytic functions. We derive various properties of the new class of normalized analytic functions X defined in the new domain, including the sharp estimates for the coefficients a 2 , a 3 , and a 4 , and for three second-order and third-order Hankel determinants, H 2 , 1 X , H 2 , 2 X , and H 3 , 1 X . The optimality of each obtained estimate is given as well. [ABSTRACT FROM AUTHOR]

Many researchers have defined the q-analogous of differential and integral operators for analytic functions using the concept of quantum calculus in the geometric function theory. In this study, we conduct a comprehensive investigation to identify the uses of the Sălăgean q-differential operator for meromorphic multivalent functions. Many features of functions that belong to geometrically defined classes have been extensively studied using differential operators based on q-calculus operator theory. In this research, we extended the idea of the q-analogous of the Sălăgean differential operator for meromorphic multivalent functions using the fundamental ideas of q-calculus. With the help of this operator, we extend the family of Janowski functions by adding two new subclasses of meromorphic q-starlike and meromorphic multivalent q-starlike functions. We discover significant findings for these new classes, including the radius of starlikeness, partial sums, distortion theorems, and coefficient estimates. [ABSTRACT FROM AUTHOR]

The principal character of a representation of the free group of rank two into PSL (2 , ℂ) is a triple of complex numbers that determines an irreducible representation uniquely up to conjugacy. It is a central problem in the geometry of discrete groups and low dimensional topology to determine when such a triple represents a discrete group which is not virtually abelian, that is, a Kleinian group. A classical necessary condition is Jørgensen's inequality. Here, we use certain shifted Chebyshev polynomials and trace identities to determine new families of such inequalities, some of which are best possible. The use of these polynomials also shows how we can identify the principal character of some important subgroups from that of the group itself. [ABSTRACT FROM AUTHOR]

Ocean transform faults often generate characteristic earthquakes that repeatedly rupture the same fault patches. The westernmost Gofar transform fault quasi‐periodically hosts ∼M6 earthquakes every ∼5 years, and microseismicity suggests that the fault is segmented into five distinct zones, including a rupture barrier zone that may have modulated the rupture of adjacent M6 earthquakes. However, the relationship between the systematic slip behavior of the Gofar fault and the fault material properties is still poorly known. Specifically, the role of pore fluids in regulating the slip of the Gofar fault is unclear. Here, we use differential travel times between nearby earthquakes to estimate the in‐situ Vp/Vs of the fault‐zone materials. We apply this technique to the dataset collected by an ocean‐bottom‐seismometer network deployed around the Gofar fault in 2008, which recorded abundant microearthquakes, and find a moderate Vp/Vs of 1.75–1.80 in the rupture barrier zone and a low Vp/Vs of 1.61–1.69 in the down‐dip edge of the 2008 M6 rupture zone. This lateral variation in Vp/Vs may be caused by both pore fluids and chemical alteration. We also find a 5%–10% increase in Vp/Vs in the barrier zone during the 9 months before the mainshock. This increase may have been caused by fluid migrations or slip transients in the barrier zone. Plain Language Summary: Oceanic transform faults are ideal natural laboratories for studying earthquake physics due to their regular behaviors. The westernmost Gofar transform fault near the East Pacific Rise generates magnitude six earthquakes every 5–6 years on two rupture zones, respectively, which are separated by a barrier zone repeatedly stopping ruptures on the adjacent segments. The distinct behavior of the barrier zone might be due to differences in material properties from the rupture zones. To explore this hypothesis, we analyze thousands of small earthquakes in 2008 and find that the barrier zone has a higher ratio between P and S velocities than the rupture zone. This difference indicates that the barrier and rupture zones differ in their fluid content and chemical composition, which may have regulated their distinct slip behaviors. We also find an increase in the ratio between P and S velocities in the barrier zone during the 9 months before the magnitude six earthquake in 2008, which may reflect fluid flows or aseismic fault slips. Our findings suggest that pore fluids and the chemical composition of fault‐zone materials likely play a crucial role in regulating the slip behaviors of oceanic transform faults. Key Points: Rupture barrier zone has a moderate Vp/Vs of 1.75–1.80Down‐dip edge of the 2008 M6 mainshock has a low Vp/Vs of 1.61–1.69Vp/Vs in the rupture barrier zone increased in the 9 months before the mainshock [ABSTRACT FROM AUTHOR]

This article defines a new operator called the q-Babalola convolution operator by using quantum calculus and the convolution of normalized analytic functions in the open unit disk. We then study a new class of analytic and bi-univalent functions defined in the open unit disk associated with the q-Babalola convolution operator. The main results of the investigation include some upper bounds for the initial Taylor–Maclaurin coefficients and Fekete–Szego inequalities for the functions in the new class. Many applications of the finds are highlighted in the corollaries based on the various unique choices of the parameters, improving the existing results in Geometric Function Theory. [ABSTRACT FROM AUTHOR]

Oceanic transform faults accommodate plate motions through both seismic and aseismic slips. However, deformation partition and slip mode interaction at these faults remain elusive mainly limited by rare observations. We use 1‐year ocean bottom seismometer data collected in 2008 to detect and locate earthquakes at the westernmost Gofar transform fault. The ultra‐fast slipping rate of Gofar results in ∼30,000 earthquakes during the observational period, providing an excellent opportunity to investigate interrelations between the slip mode, seismicity, and fault architecture at an unprecedented resolution. Earthquake distribution indicates that the ∼100‐km‐long Gofar transform fault is distinctly segmented into five zones, including one zone contouring a M6 earthquake that was captured by the experiment. Further, a barrier zone east of the M6 earthquake hosted abundant foreshocks preceding the M6 event and halted its active seismicity afterward. The barrier zone has two layers of earthquakes at depth, and they responded to the M6 earthquake differently. Additionally, a zone connecting to the East Pacific Rise had quasi‐periodic earthquake swarms. The seismicity segmentation suggests that the Gofar fault has multiple slip modes occurring in adjacent fault patches. Spatiotemporal characteristics of the earthquakes suggest that complex fault architecture and fluid–rock interaction play primary roles in modulating the slip modes at Gofar, possibly involving multiple concurrent physical processes. Plain Language Summary: Oceanic transform faults are apparently simple tectonic plate boundaries. However, their structures are surprisingly complex as manifested through various seismic and aseismic slip modes. The deformation partition mechanism is not well understood due to a lack of near‐field observations. Here, we use 1‐year ocean bottom seismometer data to study earthquakes at the westernmost Gofar transform fault and use these earthquakes to infer the fault slip modes. Spatiotemporal evolution of the earthquakes suggests that the fault has five distinctive zones along strike, including one zone hosted a magnitude (M) 6 earthquake captured by the experiment. The remaining zones are dominated by either seismic or aseismic slip. Such distinct variations of slip mode along strike likely originated from the complex, heterogeneous fault structure, and extensive fluid–rock interactions. Key Points: The westernmost Gofar transform fault is composed of distinct seismic and aseismic zonesThese fault zones are controlled by different slip modes and they possibly interact with each other via multiple mechanismsThe slip mode variations may result from the complex fault architecture and fluid–rock interactions at multiple scales [ABSTRACT FROM AUTHOR]

A two-generator Kleinian group f , g can be naturally associated with a discrete group f , ϕ with the generator ϕ of order two and where f , ϕ f ϕ − 1 = f , g f g − 1 ⊂ f , g , f , ϕ : f , g f g − 1 = 2. This is useful in studying the geometry of the Kleinian groups since f , g will be discrete only if f , ϕ is, and the moduli space of groups f , ϕ is one complex dimension less. This gives a necessary condition in a simpler space to determine the discreteness of f , g . The dimension reduction here is realised by a projection of principal characters of the two-generator Kleinian groups. In applications, it is important to know that the image of the moduli space of Kleinian groups under this projection is closed and, among other results, we show how this follows from Jørgensen's results on algebraic convergence. [ABSTRACT FROM AUTHOR]

Closely spaced, multi‐strand ridge transform faults (RTFs) accommodate relative motions along fast spreading mid‐ocean ridges. However, the relations between RTFs and plate spreading dynamics are poorly understood. The Quebrada system is one of the most unique RTF systems at the East Pacific Rise, consisting of four transform faults connected by three short intra‐transform spreading centers (ITSCs). We use seven‐months of ocean bottom seismograph data to study the Quebrada system, and find abundant earthquakes unevenly distributed among three active faults. We identify two deep, diffuse seismicity clouds at the inside corners of the ITSC‐transform fault intersections, and one seismically active fracture zone. The observations suggest a complex regional plate‐motion pattern, including possible heterogeneous rotations within the Quebrada system. Evolution of multi‐strand RTFs may have resulted from a strong three‐dimensional local thermal and fluid effects, while the RTFs may have also regulated regional tectonics, forming an intricate feedback system. Plain Language Summary: Mid‐ocean ridge transform faults (RTFs) are plate boundaries that offset adjacent mid‐ocean ridges. At fast spreading mid‐ocean ridges, such as the East Pacific Rise (EPR), closely spaced, multi‐strand RTFs are often connected by two or more short intra‐transform spreading centers (ITSCs). However, physical processes accommodating plate spreading along such multi‐strand RTF systems and the inter‐relations between the fault system and the tectonic dynamics are not well understood. Quebrada is one of such multi‐strand RTFs at the EPR. We utilize seven‐month seismic data from ocean bottom seismographs of a 2008 experiment to investigate the seismotectonics of the region. We find intriguing, abundant seismicity on one of the fracture zones, contradicting the traditional view that fracture zones are seismically quiescent. Further, we identify two diffuse seismicity clouds penetrating the uppermost mantle at the inside corners of the ITSC‐transform fault intersections, implying complex interactions among ITSCs, transform faults, and their surrounding structure. From these observations, we infer that there are rotational motions within the Quebrada fault system, which have caused slip along the fracture zone and facilitated fluid circulations to produce deep, diffuse seismicity. We speculate that there is a complex feedback system between the multi‐strand RTFs and local three‐dimensional tectonic processes. Key Points: Four segments of Quebrada transform system show significantly different seismic intensitiesOne fracture zone segment appears to be seismogenic indicating local plate rotationDeep clouds of seismicity extend into the uppermost mantle at spreading center‐ transform fault intersections [ABSTRACT FROM AUTHOR]

In this work, we investigated transport properties of the electronic states in the gate voltage-modulated skyrmion crystal (SkX). Dynamics of conducting electrons in the SkX can be described by the double-exchange model or the so-called t - J model, with the t term measuring the hopping energy of the electrons between neighboring sites and J term measuring the strength of the on-site Hund's coupling between the spin of conducting electrons and local magnetization. As a result of the Hund's coupling, the band structure of the conducting electrons in the SkX shares similar topological properties with that of gapped graphene, such as its cone-like shape, nonzero band Chern number, and edge states. By linear fitting the cone-shape energy dispersion of the electronic states in the SkX, one can obtain a gapped Dirac model similar to that of the gapped graphene. We use the Green's function technique and calculate the transmission probability of the electrons tunneling through an electrostatic barrier in the SkX expressed by the double-exchange model. Numerical results of the transport properties of the SkX by the double-exchange model reproduced analytic results from the Dirac model. We further interpreted the resemblance between the transport properties of the two models by the likeness in their wave functions. [ABSTRACT FROM AUTHOR]

Inflammation and pyroptosis have crucial impacts on the development of acute kidney injury (AKI) and have been validated in a variety of existing AKI animal models. However, the mechanisms underlying wasp venom-induced AKI are still unclear. The involvement of nucleotide-binding oligomerization domain (NOD)-like receptor protein 3 (NLRP3) in some mouse models of AKI has been extensively documented, and its crucial function in controlling inflammation and pyroptosis has been highlighted. The objective of our study was to investigate the role and mechanism of NLRP3 in inflammation and pyroptosis associated with wasp venom-induced AKI. A mouse model of AKI induced by wasp venom pre-injected with an NLRP3 inhibitor was used to study the role and mechanism of NLRP3. To verify the importance of NLRP3, western blotting was performed to assess the expression of NLRP3, caspase-1 p20, and gasdermin D (GSDMD)-N. Additionally, quantitative real-time polymerase was used to determine the expression of NLRP3, caspase-1, and GSDMD. Furthermore, enzyme-linked immunosorbent assay was utilized to measure the levels of interleukin (IL)-1β and IL-18. NLRP3 was found to be the downstream signal of the stimulator of interferon genes in the wasp sting venom-induced AKI model. The administration of wasp venom in mice significantly upregulated the expression of NLRP3, leading to renal dysfunction, inflammation, and pyroptosis. Treatment with an NLRP3 inhibitor reversed the renal damage induced by wasp venom and attenuated pathological injury, inflammatory response, and pyroptosis. NLRP3 activation is associated with renal failure, inflammatory response and pyroptosis in the hyper early phase of wasp venom-induced AKI. The inhibition of NLRP3 significantly weakened this phenomenon. These findings could potentially offer a viable therapeutic approach for AKI triggered by wasp venom. [Display omitted] • NOD-like receptor protein 3 activation is associated with wasp venom induced renal dysfunction. • NOD-like receptor protein 3 inhibitor ameliorated wasp venom induced nephrotoxicity. • NOD-like receptor protein 3 inhibition reduces pyroptosis in the kidney. [ABSTRACT FROM AUTHOR]

The largest slip in great megathrust earthquakes often occurs in the 10–30 km depth range, yet seismic imaging of the material properties in this region has proven difficult. We utilize a dense onshore‐offshore passive seismic dataset from the southernmost Cascadia subduction zone where seismicity in the mantle of the subducted Gorda Plate produces S‐to‐P and P‐to‐S conversions generated within a few km of the plate interface. These conversions typically occur in the 10–20 km depth range at either the top or bottom of a ∼5 km thick layer with a high Vp/Vs that we infer to be primarily the subducted crust. We use their arrival times and amplitudes to infer the location of the top and bottom of the subducted crust as well as the velocity contrasts across these discontinuities. Comparing with both the Slab1.0 and the updated Slab2 interface models, the Slab2 model is generally consistent with the converted phases, while the Slab1.0 model is 1–2 km deeper in the 2–20 km depth range and ∼6–8 km too deep in the 10–20 km depth range between 40.25°N and 40.4°N. Comparing the amplitudes of the converted phases to synthetics for simplified velocity structures, the amplitude of the converted phases requires models containing a ∼5 km thick zone with at least a ∼10%–20% reduction in S wave velocity. Thus, the plate boundary is likely contained within or at the top of this low velocity zone, which potentially indicates a significant porosity and fluid content within the seismogenic zone. Key Points: We observe clear Ps and SP converted phases generated from the top and bottom of the oceanic crust of the subducted Gorda PlatePs and SP converted phases are used to constrain the geometry of the interface of the subducted slabAmplitude of the converted phases indicates that the subduction plate interface is a low shear‐wave velocity zone at seismogenic depth [ABSTRACT FROM AUTHOR]

Overexpression of CD30 has been reported on the surface of some T-cell lymphomas, especially on Hodgkin's lymphoma (HL) and anaplastic large cell lymphoma (ALCL). CD30 targeted immunotherapy has good clinical therapy response. We have produced a novel antibody drug conjugates (ADCs)-anti-CD30-LDM, which shows attractive tumour-targeting capability and extremely potent antitumor efficacy. To further investigate biological characteristics and promote clinical translation of anti-CD30-LDM, we constructed a radiolabeled 123I-anti-CD30-LDM to evaluate the biodistribution characteristics. The anti-CD30-LDM was radioiodinated by the Iodogen method. The radiochemical purity of 123I-anti-CD30-LDM was more over 98%, and the specific activity of 240.5 MBq/mg. The stability and the specificity of 123I-anti-CD30-LDM were evaluated in vitro. Cellular binding assays were used to evaluate the binding capabilities in CD30-positive Karpas299 cells and CD30-negative Raji cells. B-NDG mice bearing Karpas 299 and Raji xenografts were used for in vivo biodistribution studies. Our results demonstrated that anti-CD30-LDM as an ideal ADC targeted to CD30, which was labelled easily with 123I and obtained the sufficient yields. The 123I-anti-CD30-LDM preserved specific binding to CD30 in vitro and uptake in tumour xenografts in B-NDG mice. These results are encouraging for anti-CD30-LDM as a promising clinical translational candidate for various CD30 positive lymphomas and other diseases. [ABSTRACT FROM AUTHOR]

Flood visualization is an effective and intuitive tool for representing flood information from abstract spatiotemporal data. With the growing demand for flood disaster visualizations and mitigation, augmented flood visualizations that support decision makers' perspectives are needed, which can be enhanced by emerging augmented reality (AR) and 3D printing technologies. This paper proposes an innovative flood AR visualization method based on a 3D-printed terrain model and investigates essential techniques, such as the suitable size calculation of the terrain models, the adaptive processing of flood data, and hybridizing virtual flood and terrain models. A prototype experimental system (PES) based on the proposed method and a comparison experimental system (CES) based on a virtual terrain are developed to conduct comparative experiments, which combine the system performance and questionnaire method to evaluate the efficiency and usability of the proposed method. The statistical results indicate that the method is useful for assisting participants in understanding the flood hazard and providing a more intuitive and realistic visual experience compared with that of the traditional AR flood visualization method. The frame rate is stable at 60 frames per second (FPS), which means that the proposed method is more efficient than the traditional AR flood visualization method. [ABSTRACT FROM AUTHOR]

Ambient PM 2.5 pollution has been a major environmental concern in recent years. Beijing, the capital of China, is enduring frequent and severe PM 2.5 pollution. In this study, 186 valid PM 2.5 pollution episodes during the 2014-2017 period were identified and classified into four categories according to the mechanism of pollution formation and evolution. Category I often occurs in autumn, winter and early spring, depending on accumulation during stagnant weather. Category II featured by photochemistry is dominant in summer, and category III caused by dust storms occasionally occurs in spring. Category IV represents a combination during transition periods. Interannual variations show that particulate pollution decreased from 2014 to 2017, and the decline in categories I and II played the most important role. To further understand the PM 2.5 pollution patterns in Beijing, the temporal and spatial characteristics and relationships between PM 2.5 levels and meteorological features were analyzed. Category I is the main pollution type that brings forth heavy or severe pollution and has the longest duration in those cases, while category II often leads to light or moderate pollution. There is a north-south gap in the PM 2.5 levels in Beijing. The high-level pollution in category I tends to evolve northward, while the low-level pollution in category I and category II pollution tend to evolve southward and widen the north-south gap, affected by the regional transport and more local emissions in the south. Additionally, the relationship between the concentrations and meteorology also vary with the pollution categories. High relative humidity, low wind speeds and low boundary layer heights are likely to lead to category I or II pollution, but category III requires high winds. These results provide insights into the annual tendency and characteristics of Beijing's particulate pollution in recent years. Image 1 • The PM 2.5 pollution episodes from 2014 to 2017 were identified and classified. • Particle pollution has been decreasing in recent years due to the decline in accumulation and photochemistry types. • Most of the heavy and severe pollution is due to the type of accumulation. • There is a north-south gap in PM 2.5 levels in Beijing. • The relationships between PM 2.5 levels and meteorological features vary with pollution categories. [ABSTRACT FROM AUTHOR]

In this work, we used the double exchange model and studied the transport properties of the electronic states across the superconducting skyrmion crystal (SkX)–normal SkX interface. By calculating the energy dispersion and the real-space wave function of the electronic states we found topologically protected edge zero modes in the superconducting SkX nanoribbon. By consideration of the symmetry of the Hamiltonian of the bulk superconducting SkX and its nanoribbon, we found that they belong to the symmetry class D and support Majorana edge modes. To demonstrate the transport properties of these zero edge modes, we used the Green's function method and calculated the Andreev reflection coefficients of the electronic states across the superconducting SkX–normal SkX interface. Zero-mode-induced Andreev reflection peaks are demonstrated and also reflected in the tunneling current. Single-channel conductance is quantized at 2 e 2 / h and 4 e 2 / h for two-fold and four-fold degenerate Majorana bound states, respectively. • The non-equilibrium Green's function method is extended to the double-exchange model of the superconducting skyrmion crystal. • Majorana states at the edges of the infinitely long superconducting skyrmion crystal nanoribbon are found. • Transport properties of the superconducting skyrmion crystal—normal skyrmion crystal junction are investigated. [ABSTRACT FROM AUTHOR]

Abstract Stinging accidents involving wasp venom are a notable cause of acute kidney injury (AKI) in Asia. However, very little attention has been paid to the understanding of the mechanisms involved in this type of AKI. The aims of this review are to explore the evidence for the mechanisms and the therapeutic role of renal replacement therapy of wasp venom and AKI. A systematic literature search was conducted using PubMed for the association among wasp venom and AKI. Wasp venom is a complex mixture of biologically active components, including enzymes, amines, and peptides. Wasp venom may induce local anaphylaxis reactions as well as systemic reactions such as AKI. AKI may develop as a result of direct nephrotoxic effects of the venom or secondary intravascular hemolysis and/or rhabdomyolysis. Histopathological features of renal biopsies predominantly include acute tubular necrosis and acute interstitial nephritis. Renal replacement therapy, which includes intermittent hemodialysis, hemoperfusion, plasmapheresis, continuous renal replacement therapy, and peritoneal dialysis, has been used to treat severe AKI cases induced by wasp stings. Continuous renal replacement therapy appears to provide more benefit than intermittent hemodialysis in the treatment of wasp sting-induced AKI. In this review, we summarize the existing evidence of the mechanisms and treatment for venom-induced AKI, with a particular emphasis on the role of renal replacement therapy in the management of severe AKI following massive wasp stings. [ABSTRACT FROM AUTHOR]

As one of the most common and aggressive cancer types, hepatocellular carcinoma (HCC) leads to a large number of fatalities every year. However, the pathogenesis of HCC remains largely unknown. In the present study, it was identified that FEZF1-AS1 was significantly upregulated in HCC cell lines and tissues, as determined by reverse transcription-quantitative polymerase chain reaction. Additionally, it was observed that higher expression of FEZF1-AS1 in patients with HCC indicated poorer prognosis. Furthermore, it was identified that knockdown of FEZF1-AS1 markedly inhibited the proliferation, colony formation, migration and invasion of Hep3B and Huh7 cells, as determined by Cell Counting Kit-8, colony formation and Transwell assays. In terms of mechanism, it was observed that FEZF1-AS1 acted as a sponge for microRNA (miR)-4443. The results of a luciferase reporter assay revealed that overexpression of miR-4443 significantly inhibited the luciferase activity in Hep3B and Huh7 cells. Additionally, miR-4443 overexpression markedly inhibited the expression of FEZF1-AS1, and vice versa. It was additionally identified that miR-4443 was downregulated in HCC tissues. There was an inverse correlation between the expression of miR-4443 and FEZF1-AS1 in HCC tissues. Furthermore, through functional experiments, it was identified that knockdown of FEZF1-AS1 significantly inhibited the proliferation, migration and invasion of HCC cells, whereas inhibition of miR-4443 reversed these effects. Collectively, the present results demonstrated that FEZF1-AS1 acts as an oncogene by acting as a sponge for miR-4443. [ABSTRACT FROM AUTHOR]

Abstract Since Google Earth was first released in 2005, it has attracted hundreds of millions of users worldwide and made a profound impact on both academia and industry. It can be said that Google Earth epitomized the first-generation of Digital Earth prototypes. The functionalities and merits that have sustained Google Earth's lasting influence are worth a retrospective review. In this paper, we take the liberty to conduct a bibliometric study of the applications of Google Earth during 2006–2016. We aim first to quantify the multifaceted impacts, and then to develop a structured understanding of the influence and contribution associated with Google Earth. To accomplish these objectives, we analyzed a total of 2115 Scopus publication records using scientometric methods and then proceed to discussion with a selected set of applications. The findings and conclusions can be summarized as follows: (1) the impact of Google Earth has been profound and persistent over the past decade. Google Earth was mentioned in an average of 229 publications per year since 2009. (2) Broadly, the impact of Google Earth has touched upon most scientific disciplines. Specifically, during 2006–2016, Google Earth has been mentioned in 2115 publications covering all of Scopus's 26 subject areas; (3) the influence of Google Earth has largely concentrated in GIScience, remote sensing and geosciences. The extended influence of Google Earth has reached a wider range of audiences with a concentration in fields such as human geography, geoscience education and archaeology. [ABSTRACT FROM AUTHOR]

This paper presents a geometric approach to the problems in differential subordination theory. The necessary conditions for a function to be in various subfamilies of the class of starlike functions and the class of Carathéodory functions are studied, respectively. Further, several consequences of the findings are derived. [ABSTRACT FROM AUTHOR]

Through cell-based screening models, we have identified a new compound IMB5043, a thiophenylated pyridazinone, which exerted cytotoxicity against cancer cells. In the present study, we evaluated its antitumor efficacy and the possible mechanism. By MTT assay, IMB5043 inhibited the proliferation of various human cancer cells lines, especially hepatocarcinoma SMMC-7721 cells. IMB5043 blocked cell cycle with G2/M arrest, induced cell apoptosis, and inhibited the migration and invasion of SMMC-7721 cells. As verified by comet assay and γ-H2AX foci formation, IMB5043 caused DNA damage and activated ATM, Chk2 and p53 through phosphorylation. As shown by Gene microarray analysis, the differentially expressed genes in SMMC-7721 cells treated with IMB5043 were highly related to cell death and apoptosis. IMB5043 suppressed the growth of hepatocarcinoma SMMC-7721 xenograft in athymic mice. By histopathological examination, no lesions were found in bone marrow and various organs of the treated mice. Our findings reveal that IMB5043 as an active compound consisting of both pyridazinone and thiophene moieties exerts antitumor efficacy through activation of ATM-Chk2 pathway. IMB5043 may serve as a promising leading compound for the development of antitumor drugs. [ABSTRACT FROM AUTHOR]

Virtual geographic environments (VGEs) are extensively used to explore the relationship between humans and environments. Crowd simulation provides a method for VGEs to represent crowd behaviors that are observed in the real world. The social force model (SFM) can simulate interactions among individuals, but it has not sufficiently accounted for inter-group and intra-group behaviors which are important components of crowd dynamics. We present the social group force model (SGFM), based on an extended SFM, to simulate group behaviors in VGEs with focuses on the avoiding behaviors among different social groups and the coordinate behaviors among subgroups that belong to one social group. In our model, psychological repulsions between social groups make them avoid with the whole group and group members can stick together as much as possible; while social groups are separated into several subgroups, the rear subgroups try to catch up and keep the whole group cohesive. We compare the simulation results of the SGFM with the extended SFM and the phenomena in videos. Then we discuss the function of Virtual Reality (VR) in crowd simulation visualization. The results indicate that the SGFM can enhance social group behaviors in crowd dynamics. [ABSTRACT FROM AUTHOR]

Due to their strong immersion and real-time interactivity, helmet-mounted virtual reality (VR) devices are becoming increasingly popular. Based on these devices, an immersive virtual geographic environment (VGE) provides a promising method for research into crowd behavior in an emergency. However, the current cheaper helmet-mounted VR devices are not popular enough, and will continue to coexist with personal computer (PC)-based systems for a long time. Therefore, a heterogeneous distributed virtual geographic environment (HDVGE) could be a feasible solution to the heterogeneous problems caused by various types of clients, and support the implementation of spatiotemporal crowd behavior experiments with large numbers of concurrent participants. In this study, we developed an HDVGE framework, and put forward a set of design principles to define the similarities between the real world and the VGE. We discussed the HDVGE architecture, and proposed an abstract interaction layer, a protocol-based interaction algorithm, and an adjusted dead reckoning algorithm to solve the heterogeneous distributed problems. We then implemented an HDVGE prototype system focusing on subway fire evacuation experiments. Two types of clients are considered in the system: PC, and all-in-one VR. Finally, we evaluated the performances of the prototype system and the key algorithms. The results showed that in a low-latency local area network (LAN) environment, the prototype system can smoothly support 90 concurrent users consisting of PC and all-in-one VR clients. HDVGE provides a feasible solution for studying not only spatiotemporal crowd behaviors in normal conditions, but also evacuation behaviors in emergency conditions such as fires and earthquakes. HDVGE could also serve as a new means of obtaining observational data about individual and group behavior in support of human geography research. [ABSTRACT FROM AUTHOR]

The interactions between the North American, Pacific, and Gorda plates at the Mendocino Triple Junction (MTJ) create one of the most seismically active regions in North America. The earthquakes rupture all three plate boundaries but also include considerable intraplate seismicity reflecting the strong internal deformation of the Gorda plate. Understanding the stress levels that drive these ruptures and estimating the locking state of the subduction interface are especially important topics for regional earthquake hazard assessment. However owing to the lack of offshore seismic and geodetic instruments, the rupture process of only a few large earthquakes near the MTJ have been studied in detail and the locking state of the subduction interface is not well constrained. In this paper, first, we use the second moments inversion method to study the rupture process of the January 28, 2015 M w 5.7 earthquake on the Mendocino transform fault that was unusually well recorded by both onshore and offshore strong motion instruments. We estimate the rupture dimension to be approximately 6 km by 3 km corresponding to a stress drop of ∼4 MPa for a crack model. Next we investigate the frictional state of the subduction interface by simulating the afterslip that would be expected there as a result of the stress changes from the 2015 earthquake and a 2010 M w 6.5 intraplate earthquake within the subducted Gorda plate. We simulate afterslip scenarios for a range of depths of the downdip end of the locked zone defined as the transition to velocity strengthening friction and calculate the corresponding surface deformation expected at onshore GPS monuments. We can rule out a very shallow downdip limit owing to the lack of a detectable signal at onshore GPS stations following the 2010 earthquake. Our simulations indicate that the locking depth on the slab surface is at least 14 km, which suggests that the next M8 earthquake rupture will likely reach the coastline and strong shaking should be expected there. [ABSTRACT FROM AUTHOR]

This paper presents an approach to process raw unmanned aircraft vehicle (UAV) image-derived point clouds for automatically detecting, segmenting and regularizing buildings of complex urban landscapes. For regularizing, we mean the extraction of the building footprints with precise position and details. In the first step, vegetation points were extracted using a support vector machine (SVM) classifier based on vegetation indexes calculated from color information, then the traditional hierarchical stripping classification method was applied to classify and segment individual buildings. In the second step, we first determined the building boundary points with a modified convex hull algorithm. Then, we further segmented these points such that each point was assigned to a fitting line using a line growing algorithm. Then, two mutually perpendicular directions of each individual building were determined through a W-k-means clustering algorithm which used the slop information and principal direction constraints. Eventually, the building edges were regularized to form the final building footprints. Qualitative and quantitative measures were used to evaluate the performance of the proposed approach by comparing the digitized results from ortho images. [ABSTRACT FROM AUTHOR]

A common approach to derive the sky view factor (SVF) in an urban environment is to combine urban morphological modeling and computational geometry techniques. Computational methods and tools have been developed to derive SVF from digital surface models (DSMs) and small-scale three dimensional (3D) city models, but they are not well suited for accommodating large-scale 3D city models. In this paper, we present a computational framework (SVFEngine) for deriving SVF from a wide variety of 3D city models, including the recently developed oblique airborne photogrammetry-based 3D city model (OAP3D), which is a highly detailed representation of an urban environment. We compared the SVF estimates computed from a large-scale high-resolution OAP3D with those from a set of street view panoramas at 30 locations. The comparison shows that the SVF estimates obtained using both methods closely match each other with a correlation coefficient of 0.99. The result suggests that high-resolution 3D city models have the potential for deriving accurate SVF estimates. Several examples are presented to show how SVFEngine can be applied in urban environmental modeling and analysis. The source code of SVFEngine is freely available ( https://github.com/ljm355/SVFEngine ) so it can be fully integrated into a user-defined workflow. [ABSTRACT FROM AUTHOR]

Introduction: The heterocyclic compound 4‐hydroxy‐(2,2,6,6‐Tetramethylpiperidin‐1‐yl)oxyl (TEMPOL) has a protective effect on neurological function in brain tissues damaged by ischemia and hypoxia. This study explored the effects of TEMPOL pretreatment on postoperative cognitive function in aged rats under sevoflurane anesthesia, focusing on inflammatory response and oxidative stress. Methods: Sixty male rats were divided into normal control (C), sevoflurane anesthesia (S), TEMPOL pretreatment (T), and sevoflurane anesthesia + TEMPOL pretreatment (ST) groups (15 per group). Groups T and ST rats received continuous intraperitoneal TEMPOL (100 mg/kg) for 3 days, while groups C and S rats were injected with 0.9% saline. After pretreatment, groups S and ST received 3% sevoflurane anesthesia. Results: Rats in group S exhibited a longer swimming distance, longer escape latency, lower frequency of platform crossing, and shorter dwell time in the targeted quadrant than those in groups C and T. Rats in group ST exhibited a shorter swimming distance, shorter escape latency, higher frequency of platform crossing, and longer dwell time in the targeted quadrant than those in group S. The expressions of interleukin‐6, tumor necrosis factor‐α, inducible nitric oxide synthase, and Ym1/2 messenger ribonucleic acid were higher in groups S and ST rats than in groups C and T rats and lower in group ST rats than in group S rat (p <.05). Superoxide dismutase (SOD), total antioxidant capacity (T‐AOC), and glutathione peroxidase (GSH‐Px) were lower, while malondialdehyde (MDA) was higher in groups S and ST rats than in groups C and T rats (p <.05). Group ST showed higher SOD, T‐AOC, and GSH‐Px, and lower MDA than group S (p <.05). Conclusions: TEMPOL pretreatment attenuated postoperative cognitive impairment induced by sevoflurane anesthesia in aged rats. This may be attributed to the downregulation of NR2B‐CREB‐BDNF pathway, reducing the inflammatory response and oxidative stress damage in hippocampal tissue. [ABSTRACT FROM AUTHOR]

The risks of group trampling during escalator transfers were studied in this paper. A state shifting model was proposed to describe the behaviors of a pedestrian during a group trampling accident. Based on the model, a group trample during escalator transfers was simulated from the beginning of the accident to the transfer recovery using the social force model. The impacts of 6 key factors were studied including the initial location of the accident, the time taken to invoke emergency measures, pedestrian velocity, escalator velocity, time taken for a fallen pedestrian to stand up, and pedestrian traffic. The results show that (1) when an accident happens in the transfer aisle, the peak number of pinned pedestrians is higher, while when it occurs near an escalator exit, the pressure exerted on the pinned pedestrians is more serious; (2) the speed of propagation of the accident is always faster than the recovery rate, and the earlier the emergency measures are taken, the less serious the accident is; (3) overall, except for the initial location of a trampling accident, which cannot be controlled, the other five factors have positive correlations with the severity of a group trampling accident, and can be descending ordered by their impacts using a regression analysis: early measures, pedestrian traffic, short standing-up delay, pedestrian velocity, and escalator velocity. These results can be referenced in the development of countermeasures to reduce group trampling risks. [ABSTRACT FROM AUTHOR]

Physically based realistic simulations enhance our understanding of complex environmental systems. In this paper, we analyse human perceptions of shallow water phenomena and present a set of physically based methods to visualize the dynamics of shallow water. A graphical processing units-based computing framework is shown to facilitate interactive visualization. The Saint–Venant model is adopted to describe shallow water dynamics. High-frequency waves are reconstructed from the flow directions to enrich the high-frequency waves for coarsely scaled georeferenced grids and to provide a better representation of the underlying flow field. The light-transport model is derived based on a simplified radioactive transfer process in which the scattering and absorption of water can be parameterized to reflect the optical behaviours of various water constituents. The experiments demonstrate that the proposed visualization methods can provide enhanced realism for physically based shallow water simulation. [ABSTRACT FROM PUBLISHER]

Due to advances in rendering techniques and hardware capability, stereoscopic 3D (s3D) visualization is becoming increasingly common in daily life. However, this does not change the fact that stereo effects and visual comfort depend greatly on how the related parameters are controlled during the production of the s3D images. In geo-virtual reality systems, which are important browsers for Digital Earth, the maintenance of these parameters is deeply related to the navigation process. Therefore, the navigation method in such systems requires special care. This paper presents a new flying method based on aCubemapstructure. The method defines aVehiclemodel and modifies the originalCubemapstructure by adding a front view camera during the navigation; it allows the users to fly through a virtual geographic environment with automatic speed control, smooth collision resolution, and dynamic adjustment of the s3D-related parameters. A user test was conducted to compare this new method with the original method based on theCubemapstructure. The results show that the new method performs better than the former one for it provides a convenient interaction experience with improved stereoscopic effect, and diminishes visual discomfort. [ABSTRACT FROM PUBLISHER]

Accurate estimation of phytoplankton chlorophyll-a(chl-a) concentration from remote sensing data is challenging due to the complex optical properties of case II waters. Recently, a novel semi-analytical four-band model was developed to estimate chl-aconcentration in turbid productive waters. The objective of this study was to evaluate the performance of the four-band model and extend its application to hyperspectral satellite data for estimating chl-aconcentration in Qiandao Lake of China. Based on field spectral measurements and in situ water sampling, the four-band model expressed as [Rrs−1(661.6) –Rrs−1(706.7)] [Rrs−1(714.8) –Rrs−1(682.2)]−1was calibrated after band tuning, whereRrs−1represents the reciprocal of the remote sensing reflectance. The spectral-based four-band model accounted for more than 88% of variance in chl-aconcentration with a root mean square error (RMSE) of 1.47 μg l−1. To justify the potential of this model with satellite data, comparable wavelengths selected from HJ-1A Hyperspectral Imager (HSI) imagery were utilized to calibrate the four-band model. The HSI-based model explained about 80% of chl-avariation with an RMSE of 1.35 μg l−1. Experimental results also showed that the four-band model outperformed its three-band counterpart. The results validated the rationale of the four-band model and demonstrated the effectiveness of this model for estimating chl-aconcentration from both in situ spectral data and HJ-1A hyperspectral satellite imagery. [ABSTRACT FROM AUTHOR]

Typhoons are usually accompanied by strong winds, heavy rain, storm surges and other disastrous events, and they are the most severe weather phenomena in the western part of the North Pacific Ocean. Visualisation is a key technology for analysing and presenting climate simulations and observations together with related social and ecological data. Virtual globes are a logical platform for visualising such geospatial data via the Internet. To implement interactive visualisation of typhoon data within virtual globes, this study provides a 3D texture-mapping algorithm to render volume textures on a globe. In addition, a systematic framework is proposed in which a hierarchical octree-based multiresolution data structure is implemented to organise the large volume dataset, and a graphics processing unit-based dynamic interpolation approach is proposed to obtain a smooth effect. Finally, the structure is combined with a level of detail strategy to enable the rendering of dynamic volumetric data at an acceptable interactive frame rate. To demonstrate the capabilities of this framework, data for a simulated typhoon event were rendered in World Wind, an open-source virtual globe. The experimental results demonstrate that the application of the proposed strategies can result in an interactive visualisation performance that renders typhoon data on virtual globes. [ABSTRACT FROM PUBLISHER]

It is difficult to obtain accurate simulation results without observation data. So using real-time dynamic observation data in the simulation process has become an academic frontier of international research. This paper is a probing research on the data-driven adaptive modeling and automatic refactoring methods of flood routing simulation. A cellular automata (CA) data-driven flooding model was developed using the Hunhe River in Shenyang City as a case study. The proposed model can increase the accuracy of simulations by calculating differences in the water stages using high temporal resolution observational data. Meanwhile, corresponding parameter analysis was carried out based on the proposed CA model and the best lagging time between simulation and observation was discussed. [ABSTRACT FROM PUBLISHER]

The congestion risk during escalator transfers was simulated based on a modified social force model. A four-stage transfer model was proposed. A projection strategy was employed to calculate the social forces for inclined surfaces, and a schedule-line model was proposed to calculate the targets adaptively. Realistic simulations of escalator transfer activities were achieved. The results demonstrate that the spatial distribution of the congestion risks is inhomogeneous. A few areas contain clearly higher risks, and the congestion risk is higher in the transfer aisles than on the escalators. The congestion risk in the transfer aisle is influenced more by the average pedestrian speed than that of the escalators. Slower walkers in the transfer aisle may cause congestion, which is more serious when the escalator speed is faster than that of the pedestrians. Therefore, to reduce the congestion risk, the speed of the escalator should be set slower than the average speed of the pedestrians, and conductors can be employed to divert the traffic at the entrance, turns, and exit of the escalator. [ABSTRACT FROM AUTHOR]

Photovoltaic energy has become a popular renewable energy source for sustainable urban development. As a result, 3D solar radiation models are needed to facilitate the interactive assessment of photovoltaic potential in complex urban environments. SURFSUN3D is a visualization-oriented full 3D solar radiation model that has been shown to achieve efficient computation and visualization for 3D urban models. The present paper introduces a framework to integrate SURFSUN3D into a 3D GIS-based application to interactively assess the photovoltaic potential in urban areas. [ABSTRACT FROM AUTHOR]

Visualization is an important component of the evaluation of meteorological models, forecasting research, and other applications. With advances in computing power, the volume of meteorological data generated by geoscience and climate researchers has been steadily increasing. The emerging technique of virtual globes has been regarded as an ideal platform for visualizing larger geospatial data over the Internet. To visualize and analyze meteorological data with the new virtual globes, this paper proposes a systematic meteorological data visualization (MDV) framework in World Wind, an open-source virtual globe. The key technologies, including a hierarchical octree-based multiresolution data organization, data scheduling, level of detail (LOD) and rendering are described in detail. The framework is then applied to a practical tropical cyclone simulation, including flow vectors, particle tracking, cross-sectional analysis, streamlines, pathway animation, and volume rendering. The results show that virtual globes are effective tools for meteorological data visualization and analysis. [ABSTRACT FROM AUTHOR]

Abstract: A type of trampling process that is caused by picking-up activities during escalator transfers was studied in this paper. A five-stage trampling model for individual pedestrians was proposed, and the social force model was modified considering the transfer features. Several scenarios were simulated to study the impacts of 4 factors, namely, pedestrian traffic, escalator velocity, picking-up duration and pedestrian velocity, on trampling probability. The results show that pedestrian traffic strongly affects the trampling probability, with a positive correlation throughout all scenarios; the picking-up duration affects the trampling probability, with a negative correlation throughout all scenarios; lower pedestrian velocities can result in higher trampling probabilities if the picking-up duration is short; and the escalator velocity may also affect the trampling probability, but there are no general rules for all scenarios. Thus, the impacts of these 4 factors can be queued in descending order as follows: pedestrian traffic picking-up duration pedestrian velocity escalator velocity. Countermeasures can be employed according to the results to reduce trampling risks. [Copyright &y& Elsevier]

[Display omitted] Mithramycin A (MIT) has reacquired extensive research attention due to its anti-solid tumor activity and improved pharmacological production. Mechanismly, MIT was broadly used as a c-Myc inhibitor, and c-Myc regulated CD47 and PD-L1 expression which has been demonstrated. However, how MIT affects immune check-point molecules remains unknown. In this study, we found CD47 expression was higher in melanoma of pan-tissue array. MIT inhibited CD47 expression both in mRNA and protein level in melanoma cells (SK-MEL-28 and B16). MIT inhibited c-Myc, Sp-1 and CD47 expression in a concentration-dependent way. MIT inhibited the surface CD47 expression and promoted the phagocytosis of SK-MEL-28 cells by THP-1 cells. We found MIT inhibited tumor growth in melanoma allograft mice and CD47 expression in tumor mass. We also found MIT upregulated PD-L1 expression in cancer cells possibly via inhibiting PD-L1 ubiquitination, increasing ROS and IFN-γ. Combination of MIT and anti-PD-1 antibody showed enhanced antitumor activity compared to MIT and anti-PD-1 antibody alone in MC38 allograft mice. Using immune checkpoint array we found MIT inhibited expression of FasL and Galectin3. These results suggest that MIT inhibits CD47 expression, while improves PD-L1 expression. Furthermore, the combination of MIT and anti-PD-1 antibody exerts potent antitumor effect. [ABSTRACT FROM AUTHOR]

The visual perception of augmented reality (AR) geovisualization is significantly different from traditional controllable 2D and 3D visualization. In this study, we extended the rendering styles of color variables to include natural material color (NMC) and illuminating material color (IMC) and extended the size to include linear size (LS) and angular size (AS). Outdoor AR geovisualization user experiments were conducted, examining the guidance characteristics of five static variables (NMC, IMC, shape, AS, LS) and two dynamic variables (vibration, flicker). The results showed that the two dynamic variables provided the highest guidance, and among all the static variables, the order of guidance was shape, IMC, AS, NMC, and finally LS. This is a new finding that is different from the color, size, and shape guidance order in 2D visualization and the color, shape, and size order in 3D visualization. The results could be utilized to guide the selection of visual variables for symbol design in AR geovisualization. [ABSTRACT FROM AUTHOR]

Abstract: Volumetric ray-casting is a widely used algorithm in volume visualization, but implementing this algorithm to render atmospheric volume data that cover a large area on virtual globes constitutes a challenging problem. Because atmospheric data are usually georeferenced to a spherical coordinate system described by longitude, latitude and altitude, adaptations to the conventional volumetric ray-casting method are needed to accommodate spherical volume texture sampling. In this paper, we present a volumetric ray-casting framework to visualize atmospheric data that cover a broad but thin geographic area (because of the thinness of Earth׳s atmosphere). Volume texture conforming to the spherical coordinate system of a virtual globe can be created directly from the spherical volume data to avoid oversampling, undersampling or a loss of accuracy due to reprojecting and resampling such data into a Cartesian coordinate system. Considering the insignificant physical thickness of the atmosphere of the Earth, the ray-casting method presented in this paper also allows for real-time vertical scaling (exaggeration of the altitudinal range) without the need to re-process the volume texture, enabling convenient visual observation of the altitudinal variations. The spherical volume ray-casting method is implemented in a deferred rendering framework to integrate the volume effects into a virtual globe composed of a variety of background geospatial data objects, such as terrain, imagery, vector shapes and 3D geometric models. [Copyright &y& Elsevier]

To avoid crowd evacuation simulations depending on 2D environments and real data, we propose a framework for crowd evacuation modeling and simulation by applying deep reinforcement learning (DRL) and 3D physical environments (3DPEs). In 3DPEs, we construct simulation scenarios from the aspects of geometry, semantics and physics, which include the environment, the agents and their interactions, and provide training samples for DRL. In DRL, we design a double branch feature extraction combined actor and critic network as the DRL policy and value function and use a clipped surrogate objective with polynomial decay to update the policy. With a unified configuration, we conduct evacuation simulations. In scenarios with one exit, we reproduce and verify the bottleneck effect of congested crowds and explore the impact of exit width and agent characteristics (number, mass and height) on evacuation. In scenarios with two exits and a uniform (nonuniform) distribution of agents, we explore the impact of exit characteristics (width and relative position) and agent characteristics (height, initial location and distribution) on agent exit selection and evacuation. Overall, interactive 3DPEs and unified DRL enable agents to adapt to different evacuation scenarios to simulate crowd evacuation and explore the laws of crowd evacuation. [ABSTRACT FROM AUTHOR]

Chemoresistance has been associated with increased reliance on mitochondrial functions in many cancers, including lung cancer. Atovaquone is an anti-malaria drug and mitochondrial inhibitor. In this work, we attempted to explore whether atovaquone can be repurposed for lung cancer treatment to overcome chemoresistance. We showed that atovaquone inhibited proliferation, colony formation and survival in non-small cell lung cancer cell (NSCLC) cells. Of note, the effective dose of atovaquone was clinically achievable. Combination index value indicated that atovaquone and carboplatin were synergistic in inhibiting NSCLC. The potent efficacy of atovaquone and its synergism with chemotherapeutic drug were also demonstrated in NSCLC xenograft mice model. Mechanism studies showed that the synergism between atovaquone and carboplatin was due to atovaquone's ability in disrupting mitochondrial functions via specifically inhibiting complex III induced oxygen consumption. Subsequently, atovaquone activated AMP-activated protein kinase (AMPK) and inhibited mammalian target of rapamycin (mTOR) signaling. AMPK inhibition reversed the anti-NSCLC activity of atovaquone, suggesting that the action of atovaquone is also dependent on AMPK. Our work suggests that atovaquone is an attractive candidate for NSCLC treatment. Our findings emphasize that inhibition of mitochondrial function is a promising therapeutic strategy to enhance NSCLC chemosensitivity. [ABSTRACT FROM AUTHOR]

The word "symmetry" is a Greek word that originated from "symmetria". It means an agreement in dimensions, due proportion, and arrangement; however, in complex analysis, it means objects remaining invariant under some transformation. This idea has now been recently used in geometric function theory to modify the earlier classical q-derivative introduced by Ismail et al. due to its better convergence properties. Consequently, we introduce a new class of analytic functions by using the notion of q-symmetric derivative. The investigation in this paper obtains a number of the latest important results in q-theory, including coefficient inequalities and convolution characterization of q-symmetric starlike functions related to Janowski mappings. [ABSTRACT FROM AUTHOR]

Assessing short-term exposure to PM 2.5 requires the concentration distribution at a high spatiotemporal resolution. Abundant researches have derived the daily predictions of fine particles, but estimating hourly PM 2.5 is still a challenge restrained by the input data. The recent aerosol optical depth (AOD) product from Himawari-8 provides hourly satellite observations informative to modelling. In this study, we developed separate random forest models with and without AOD and combined the estimates to obtain a full-coverage hourly PM 2.5 distribution. 10-fold cross validation R2 ranged from 0.92 to 0.95 and root mean square errors from 14.1 to 16.9 μg/m3, indicating the good model performance. Spatial convolutional layers of PM 2.5 measurements and temporal accumulation effects of meteorological features were added into the model. They turned out to be of the most important predictors and improved the performance significantly. Finally, we mapped hourly PM 2.5 at a 1-km resolution in Beijing during a pollution episode in 2019 and studied the pollution pattern. The study proposed a method to obtain 24-h full-coverage hourly PM 2.5 estimates which are useful for acute exposure assessment in epidemiological researches. Unlabelled Image • Separate random forest models were built with and without AOD to obtain full-coverage hourly PM 2.5 estimates. • The use of spatial autocorrelation and temporal accumulation improved the models significantly. • Himawari-8 AOD worked on the spatial trends explanation and was important to estimates in remote regions. [ABSTRACT FROM AUTHOR]

• We extend the double exchange model of the skyrmion crystal by taking into account the next-nearest-neighbor hopping. • Techniques to solve the Hamiltonian within and without the strong coupling limit are elaborated. • Numerical results of the bulk Chern number and nanoribbon edge states are obtained. • Topological phase transitions driven by the topological number change and next-nearest-neighbor hopping are discussed. By considering the topological Hall conductivity and the nanoribbon edge states, i.e., the bulk-boundary correspondence of the skyrmion crystal (SkX), this work focused on the relation of the topological properties to the next-nearest-neighbor (nnn) hopping (t ′), the exchange coupling strength (J), and the topological number of the skyrmion (Q sk). When the nnn hopping of the electrons coexists with the nearest-neighbor hopping, the flux pattern of the emergent magnetic field traversing the SkX is reshaped giving rise to different topological Hall effect. By increasing t ′ from 0 to t , we found the Chern numbers of the electronic bands change from unity to indefinite values demonstrating a phase transition. By continually increasing Q sk from 1 to 2, we found topological phase transitions occur at Q sk = 1.3 and 1.7. We also considered the effect of finite J and found the results obtained in the adiabatic limit (J ≫ t) hold to around J = t. [ABSTRACT FROM AUTHOR]

To overcome the difficulties of quantitatively optimizing and evaluating evacuation guidance systems, we proposed a perception model based on virtual reality (VR) experiments and the social force model (SFM). We used VR and eye tracking devices to carry out experiments. The VR experiment data was mainly used for three purposes: to determine the parameter values of the perception model, to optimize the evacuation guidance system by quantitative analysis, and to validate the perception model. Additionally, we compared the VR experimental and model simulation results before and after the optimization to quantitatively assess the improvement in the optimized evacuation guidance system. The results showed that our model can effectively simulate the perception behaviors of evacuees on the evacuation guidance system and it can quantitatively evaluate different evacuation guidance system schemes. The model simulations showed that the optimized evacuation guidance system improved the evacuation efficiency, with the average escape time and distance of the two starting positions reduced by 37% and 28%, respectively. [ABSTRACT FROM AUTHOR]

Solar3D is an open-source software application designed to interactively calculate solar irradiation on three-dimensional (3D) surfaces in a virtual environment constructed with combinations of 3D-city models, digital elevation models (DEMs), digital surface models (DSMs) and feature layers. The GRASS GIS r.sun solar radiation model computes solar irradiation based on two-dimensional (2D) raster maps for a given day, latitude, surface and atmospheric conditions. With the increasing availability of 3D-city models and demand for solar energy, there is an urgent need for better tools to computes solar radiation directly with 3D-city models. Solar3D extends the GRASS GIS r.sun model from 2D to 3D by feeding the model with input, including surface slope, aspect and time-resolved shading, which is derived directly from the 3D scene using computer graphics techniques. To summarize, Solar3D offers several new features that—as a whole—distinguish this novel approach from existing 3D solar irradiation tools in the following ways. (1) Solar3D can consume massive heterogeneous 3D-city models, including massive 3D-city models such as oblique airborne photogrammetry-based 3D-city models (OAP3Ds or integrated meshes); (2) Solar3D can perform near real-time pointwise calculation for duration from daily to annual; (3) Solar3D can integrate and interactively explore large-scale heterogeneous geospatial data; (4) Solar3D can calculate solar irradiation at arbitrary surface positions including on rooftops, facades and the ground. [ABSTRACT FROM AUTHOR]

Transport emissions and street dust are important sources of summertime air pollution in urban centers. Street greening and buildings have an influence on the diffusion of air pollution from streets. For field measurements, many studies have analyzed the effect of street green space arrangement on the diffusion of air pollution, but these studies have neglected the patterns at the landscape scale. Other studies have analyzed the effects of the large scale of green space on air pollution, but the vertical distribution of street buildings and greening has rarely been considered. In this study, we analyzed the impact of the vertical distribution of urban street green space on summertime air pollution in urban centers on the urban scale for the first time by using a deep-learning method to extract the vertical distribution of street greening and buildings from street view image data. A total of 687,354 street view images were collected. The green index and building index were proposed to quantify the street greening and street buildings. The multilevel regression method was used to analyze the association between the street green index, building index and air pollution indexes. For the cases in this study, including the central urban areas of Beijing, Shanghai and Nanjing, our multilevel regressions results suggested that, in the central area of the city, the vertical distribution of street greening and buildings within a certain range of the monitoring site is association with the summertime air pollution index of the monitoring site. There was a significant negative association between the street greening and air pollution indexes (radius = 1–2 km, NO2, p = 0.042; radius = 3–4 km, AQI, p = 0.034; PM10, p = 0.028). The street length within a certain range of the monitoring site has a positive association with the air pollution indexes (radius = 1–2 km, AQI, p = 0.072; PM10, p = 0.062). With the increase of the distance between streets and the monitoring sites, the association between streets and air pollution indexes decreases. Our findings on the association between the vertical structure of street greening, street buildings and summertime air pollution in urban centers can support urban street planning. [ABSTRACT FROM AUTHOR]

At present, a common drawback of crowd simulation models is that they are mainly simulated in (abstract) 2D environments, which limits the simulation of crowd behaviors observed in real 3D environments. Therefore, we propose a deep reinforcement learning-based model with human-like perceptron and policy for crowd evacuation in 3D environments (HDRLM3D). In HDRLM3D, we propose a vision-like ray perceptron (VLRP) and combine it with a redesigned global (or local) perceptron (GOLP) to form a human-like perception model. We propose a double-branch feature extraction and decision network (DBFED-Net) as the policy, which can extract features and make behavioral decisions. Moreover, we validate our method's ability to reproduce typical phenomena and behaviors through experiments in two different scenarios. In scenario I, we reproduce the bottleneck effect of crowds and verify the effectiveness and advantages of HDRLM3D by comparing it with real crowd experiments and classical methods in terms of density maps, fundamental diagrams, and evacuation times. In scenario II, we reproduce agents' navigation and obstacle avoidance behaviors and demonstrate the advantages of HDRLM3D for crowd simulation in unknown 3D environments by comparing it with other deep reinforcement learning-based models in terms of trajectories and numbers of collisions. [ABSTRACT FROM AUTHOR]

Visual localization nowadays is a research hotspot in computer vision and photogrammetry. It can provide meter level or higher localization accuracy under the conditions without GPS signals. However, achieving efficient, robust and high-accuracy visual localization under the condition of day-night changes is still challenging. To deal with this problem, we develop an improved lightweight deep neural network with knowledge distillation to efficiently extract deep local features from imagery while maintaining strong robustness for day-night visual localization. Furthermore, to further improve the accuracy of visual localization, we use aligned dense LiDAR point clouds and imagery collected by a new portable camera-LiDAR integrated device to build a prior map, and directly utilize the 2D-3D correspondences between 2D local feature points extracted by our lightweight network and 3D laser points retrieved from the prior map for localization. Moreover, we build our own ground truth point cloud dataset at 5 cm accuracy to evaluate the accuracy of the constructed prior map as well as a day-night dataset including prior map and verification data for the evaluation of the proposed visual localization method. The experimental results prove that our visual localization method achieves a balance between the efficiency and robustness while improving localization accuracy for day-night visual localization. In a comparison with a variety of state-of-the-art local feature extraction methods based on deep neural networks, our lightweight network has the least number of parameters (0.2 million) and reaches the highest feature extraction efficiency (92 frames per second), which is on par with that of the classic real-time ORB feature extraction method. Furthermore, our network remains competitive with other advanced deep local feature extraction networks in feature matching and day-night visual localization. In addition, evaluations performed on our own dataset demonstrate that our visual localization method using images and LiDAR point clouds provides a localization error of 1.2 m under the conditions of day-night changes, which is much smaller than those achieved by a state-of-the-art, purely visual localization method. [ABSTRACT FROM AUTHOR]

In order to study the crowd evacuation process in complex subway stations, this paper proposes a social group perception evacuation model based on the social group evacuation model and the perception evacuation model, combined with the spatial index algorithm and the social group random algorithm, and takes a real subway station as an example to simulate the crowd evacuation process. Through the simulation results, the evacuation bottlenecks in the subway station are analyzed and the influence of social groups on evacuation efficiency is also verified. The results show that subway gates, fenced aisles and exits are important bottlenecks for crowd evacuation in subway stations, and the social groups will reduce the evacuation efficiency. This model can more truly restore the interaction behavior between evacuees and the environment in the evacuation process, and is suitable for the real complex subway stations. • Bottlenecks that affecting evacuation efficiency in subway stations mainly include subway gates, fenced aisles and exits. • Social groups have an important effect on evacuation efficiency. • The variation trends of panic index of individuals and social groups under different desired velocities are basically the same. [ABSTRACT FROM AUTHOR]