bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimization of the Rheological Properties of Self-Assembled Tripeptide/Alginate/Cellulose Hydrogels for 3D Printing
Authors: Hernández-Sosa Alejandro , Ramírez-Jiménez Rosa Ana , Rojo Luis , Boulmedais Fouzia , Aguilar María Rosa , Criado-Gonzalez Miryam , Hernández Rebeca
Published: May 2022

3D printing is an emerging and powerful technique to create shape-defined three-dimensional structures for tissue engineering applications. Herein, different alginate–cellulose formulations were optimized to be used as printable inks. Alginate (Alg) was chosen as the main component of the scaffold due to its tunable mechanical properties, rapid gelation, and non-toxicity, whereas microcrystalline cellulose (MCC) was added to the hydrogel to modulate its mechanical properties for printing. Additionally, Fmoc-FFY (Fmoc: 9-fluorenylmethoxycarbonyl; F: phenylalanine; Y: tyrosine), a self-assembled peptide that promotes cell adhesion was incorporated into the ink without modifying its rheological properties and shear-thinning behavior. Then, 3D-printed scaffolds made of Alg, 40% of MCC inks and Fmoc-FFY peptide were characterized by scanning electron microscopy and infrared spectroscopy, confirming the morphological microstructure of the hydrogel scaffolds with edged particles of MCC homogeneously distributed within the alginate matrix and the self-assembly of the peptide in a β-sheet conformation. Finally, the cytocompatibility of the scaffolds was tested in contact with the MG63 osteosarcoma cells, confirming the absence of cytotoxic components that may compromise their viability. Interestingly, MG63 cell growth was retarded in the scaffolds containing the peptide, but cells were more likely to promote adhesive interactions with the material rather than with the other cells, indicating the benefits of the peptide in promoting biological functionality to alginate-based biomaterials.
Cytochrome P450 3A2 and PGP-MDR1-Mediated Pharmacokinetic Interaction of Sinapic Acid with Ibrutinib in Rats: Potential Food/Herb–Drug Interaction
Authors: Iqbal Muzaffar , Raish Mohammad , Ahmad Ajaz , Ali Essam A. , Bin Jardan Yousef A. , Ansari Mushtaq A. , Shahid Mudassar , Ahad Abdul , Alkharfy Khalid M. , Al-Jenoobi Fahad I.
Published: May 2022

Ibrutinib (IBR) metabolism (primarily by CYP3A enzyme) is the main route of excretion for IBR, which could lead to drug–drug/herb–drug interactions with herbal medicines, nutritional supplements, and other foods. Sinapic acid (SA) is a bioactive phytonutrient that is used as a dietary supplement to treat a variety of illnesses. Pharmacokinetic interactions may occur when IBR interacts with SA, which influences the pharmacokinetic processes such as absorption, distribution, metabolism, and excretion. Therefore, it is obligatory to investigate the safety apprehensions of such parallel usage and to evaluate the possible impact of SA on the pharmacokinetics of IBR and propose a possible interaction mechanism in an animal model. The IBR concentration in plasma samples was determined using a validated UHPLC-MS/MS method after administration of a single oral dosage of IBR (50 mg/kg) in rats with or without SA pretreatment (40 mg/kg p.o. each day for 7 days, n = 6). The co-administration of IBR with SA displayed significant increases in Cmax ~18.77%, AUC0–T ~28.07%, MRT ~16.87%, and Kel ~24.76%, and a significant decrease in the volume of distribution Vz/F_obs ~37.66%, the rate of clearance (Cl/F) ~21.81%, and T½ ~20.43%, respectively, were observed as compared to rats that were administered IBR alone, which may result in increased bioavailability of IBR. The metabolism of IBR in the liver and intestines is significantly inhibited when SA is given, which may lead to an increase in the absorption rate of IBR. These findings need to be investigated further before they can be used in clinical practice.
Experimental Studies of Nonlinear Dynamics of Asynchronous Electric Drives with Variable Load
Authors: Kodkin Vladimir , Anikin Alexander
Published: May 2022

This article presents the results of the analysis of experimental data that were obtained during industrial tests of an adjustable asynchronous traction electric drive of a shuttle car for the mining industry. During these tests, by changing the parameters of the stator voltage, the stator currents of the induction motor were optimized when the load changes over a wide range (from −1.5 Tn to + 1.5 Tn). The authors managed to significantly reduce the effective values of the stator currents of the motor, but at the same time it was found that, with the load and even the rate of its change, oscillations of the effective values of currents with variable amplitude and frequency occur. It turned out to be very difficult to explain these oscillations and the variability of their parameters using traditional mathematical methods for describing processes in asynchronous electric motors. Vector equations and diagrams are valid only at constant frequencies of the stator voltage and, in the modes of their significant changes, which exist during self-oscillations of the effective values of the motor stator current, their error is very large. To analyze the conditions of the self-oscillations, it was proposed to use nonlinear continuous transfer functions that describe the formation of torque in induction motors. The article shows how such transfer functions make it possible to take into account the influence of the load torque and the speed of its change on the parameters of the self-oscillations of the effective values of the stator current of asynchronous electric drives experiencing such loads. The article proposes a qualitative analysis of the results of experiments carried out on real tracks of the movement of the shuttle car. The analysis of experimental data confirmed the effectiveness of using nonlinear transfer functions to evaluate the dynamics of asynchronous electric drives and the sufficient accuracy of the proposed method. In the course of research, it is shown how the conditions of the boundary stability of the drive depend on external loads that change the nonlinear transfer function of the induction motor. As a result, it was found that the condition of boundary stability and the parameters of the self-oscillations are affected not only by the magnitude, but also by the rate of load change. The article made assumptions about possible options for the effective correction of asynchronous electric drives experiencing variable loads.
Residence Time Distribution of Non-Spherical Particles in a Continuous Rotary Drum
Authors: Mahdavy Saeed , Norouzi Hamid Reza , Jordan Christian , Haddadi Bahram , Harasek Michael
Published: May 2022

The motion of non-spherical particles with sharp edges, as they are commonly involved in practice, was characterized by residence time distribution (RTD) measurement in a continuous drum. Particles with two sizes, 6 and 10 mm, and two densities, 750 and 2085 kg/m3, were used in the experiments. The effects of rotation speed (3–11 rpm), incline angle (2–4°), feed rate, and mixture composition were investigated and compared to the results of other researchers on particles without sharp edges. We also fitted the RTD with an axial dispersion model to obtain a better insight into the flow behavior. MRT of non-spherical particles with sharp edges depends on ω−α similar to other shapes, while the value of alpha is higher for particles with sharp edges (0.9 < α < 1.24), especially at high incline angles. The MRT depends on incline angle, β−b, where b varies between 0.81 (at low ω) and 1.34 (at high ω), while it is close to 1 for other shapes. Feed rate has a slight effect on the MRT of particles with sharp edges and the effect of particle size diminishes when rotation speed increases. The MRT linearly increases with volume fraction of light particles in a mixture of light and heavy particles (from pure heavy to pure light particles).
Analysis of Sealing Performance of Metal B-ring Self-Tightening Structure
Authors: Gao Bingjun , Gao Han , Dong Junhua , An Yongming , Wang Chuanzhi
Published: May 2022

Process industries often use B-ring self-tightening sealing structures and rely on interference assembly to meet the initial sealing requirements. Therefore, determining reasonable B-ring material, size and interference is crucial to ensure the sealing performance of the structure. In this paper, based on elastic deformation analysis, the deformation co-ordination equation of a B-ring sealing structure was established, and a sealing contact pressure calculation formula was obtained, with discussion of the main factors affecting sealing performance. With the finite element method, transient temperature field analysis was carried out for startup and shutdown load cases, and contact analysis was carried out for interference assembly, startup and shutdown. Based on the evaluation criteria of sealing performance with proposed sealing rate and leakage parameters, the effects of material properties, interference, B-ring size, etc., on sealing performance were investigated, revealing that although a B-ring with high material yield stress can meet the sealing requirements, both the B-ring and the sealing surface of a reactor body will yield plastic deformation. B-rings with a low material yield stress exhibit obvious plastic deformation during startup and leak during shutdown. However, leakage parameters can be minimized by smaller interference and moderate wave radius.
The Effects of Payment for Environmental Services on Environmental Improvement and Poverty Reduction: A Meta-Regression Analysis
Authors: Jing Shouwu , Du Minzhe
Published: May 2022

Based on the empirical literature of the payments for environmental services (PES) projects for the environmental improvement and poverty reduction, this paper uses a meta-regression analysis method to study whether PES can achieve the effects of improving environmental quality and reducing poverty levels. For the meta-regression analysis, the literature was mainly searched by the Web of Science core journal database. The explanatory variables of meta-regression analysis are the hypothesis and related features of the models in the original literature by generally taking the binary dummy variables or categorical variables. The dependent variables used in this paper are environmental improvement and poverty reduction. The results show that PES projects based on private ownership rights are more conducive to poverty reduction and environmental improvement. If the country is a buyer of a PES project, it is more likely to achieve the effects of environmental enhancement and poverty alleviation. PES projects based on local conditions can also achieve a win–win situation for the two effects. The effects are more effective as policy implementation time is extended. The findings suggest that in developing countries, the government should set different PES projects according to different regions conditions, to promote project implementation through individual voluntary participation, and to achieve the dual purpose of environmental governance and poverty alleviation based on the expectation of long-term implementation of participant projects.
Fabrication of Multiscale 1-Octadecene Monolayer Patterned Arrays Based on a Chemomechanical Method
Authors: Shi Liqiu , Yu Feng , Hang Zhouming
Published: May 2022

A controlled and self-assembled micromachining system was built to fabricate a mico/nanoscale monolayer patterned array on a silicon surface using a diamond tip. The process was as follows: (1) we preprocessed a silicon wafer to obtain a hydrogen-terminated silicon surface; (2) we scratched three rectangular arrays of 10 μm × 3 μm with a spacing of 2 μm on the silicon surface with a diamond tip in 1-octadecene solution; the Si-H bonds were broken, and silicon free radicals were formed; (3) the 1-octadecene molecules were connected with silicon atoms based on Si-C covalent bonds, and the 1-octadecene nano monolayer was self-assembled on the patterned arrays of the silicon surface. Atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and Sessile water contact angles were used to detect and characterize the self-assembled monolayers (SAMs). The XPS results showed that the Si2p peak and the O1s peak were significantly decreased after self-assembly; however, the C1s peak was successively significantly increased. Sessile water contact angles showed that the hydrophilicity was weakened after the formation of 1-octenecene SAMs on the silicon substrate. The nanofriction of the sample was measured with AFM. The change in nanofriction also demonstrated that the SAMs were formed in accordance with the patterned array. We demonstrated that, by using this method, self-assembled multiscale structures on silicon substrate can be formed quickly and conveniently.
An Iterative Conceptual Design Process for Modular Product Based on Sustainable Analysis and Creative Template Method
Authors: Zhou Junyu , Yu Miao , Zhao Wu , Zhang Kai , Chen Jun , Guo Xin
Published: May 2022

The iterative design process of mechanical products has evolved towards a more sustainable direction driven by the concept of sustainable development. Modular design emphasizes the realization of user requirements under the condition of high efficiency and low cost, which is conducive to the diversification of product design. The sustainable innovative design methods are considered in modular design processes, which can improve the design capabilities of enterprises and enhance competitiveness. However, although the existing methods used in the iterative design of a product scheme contributes to satisfy the user requirements and generate the innovative scheme of the product, the sustainable design concepts such as the impact on the utilization of resources and environment during the iteration of the conceptual scheme and sustainability evaluation of product schemes have not been given sufficient attention. To resolve this, in this work, an iterative conceptual design process is proposed for modular products based on the sustainable analysis and creative template method. In this process, firstly, the KANO model is used to analyze the sustainable requirements of users. Secondly, a function behavior structure (FBS) model and creative template method are used to form sustainable innovative modular products conceptual design scheme. Finally, fuzzy analytic hierarchy process (FAHP) is used to evaluate the product scheme. The iterative conceptual design process proposed in this paper can be abbreviated as S-KFCF. The prototype conceptual scheme design of a novel low-temperature plasma deposition device is conducted. The results suggest that the proposed process could effectively reduce the total cost, shorten design cycles, increase product part recovery rates, and improve the environmental friendliness of the design schemes produced via sustainable analysis.
A Study of the Feasibility of Using Grey Sedge Residue to Facilitate Zero Waste Production
Authors: Chucheep Kamonwan , Suwanpayak Nathaporn , Phanchindawan Naree
Published: May 2022

There is approximately 30% of grey sedge (Lepironia articulata) residue remaining from weaving production that could add value to support zero waste management. Therefore, the aim of this research was to study the feasibility of using a residue of grey sedge or Krajood strips from weaving production to form a value-added product. To obtain preliminary data, Krajood strip residue was examined for its biological and physical properties. In addition, the biological and physical properties of Krajood strip residue in combination with loam soil (KSRL) were examined and compared with the properties of loam soil (LS) itself. The results showed that the total microbe and moisture content of the Krajood strip residue was significantly higher than that of the products made from Krajood strips (KS). The stress value of Krajood strips was higher than the stress values of other samples except for that of a bag made of paper. Identification of bacteria and mold by MALDI Biotyper and DNA sequencing compared with BLAST revealed the presence of the types of soil microbes that benefit plants. KSRL was enriched with larger amounts of the primary elements important for plant growth: nitrogen, phosphorus, and potassium, and the three second tier elements. The pH of KS, LS, and KSRL were 6.40 ± 0.14, 5.87 ± 0.04, and 5.26 ± 0.02, respectively. These results could support the use of this beneficial residue for bioresource sustainability.
Operationalizing the Vision of Catholic Social Thought Using Change Management
Authors: Puen Stephanie Ann
Published: May 2022

In Catholic social thought, magisterial documents emphasize the “See, Judge, Act” method in reflecting on social issues. While action is an important aspect of this methodology, aspects of Catholic social thought, as seen in the teaching of magisterial documents, has focused primarily on principles and the “judge” part of the method, where one reflects on the current social context in light of Catholic social thought and gospel values. This paper reminds Catholic social thought of the importance of obtaining the commitment of the people within the community in order to put Catholic social thought principles into practice structurally and that obtaining this commitment will require listening and responding to motivations, fears, values, and concerns of the people when handling conflicting goods at stake, while also offering helpful tools and resources for the work ahead. To obtain this commitment, this paper proposes how the discipline of change management offers tools for those putting Catholic social thought into practice and handling the fears, values, and concerns of the people involved. Specifically, the tools of stakeholder, culture, and ADKAR analysis in change management help practitioners implement projects grounded in the principles of Catholic social thought.
The Moderating Influence of Religiousness/Spirituality on COVID-19 Impact and Change in Psychotherapy
Authors: Jankowski Peter J. , Sandage Steven J. , Crabtree Sarah A.
Published: May 2022

The COVID-19 pandemic has spurred a global surge in empirical research examining the influence of the pandemic on individuals’ mental health symptoms and well-being. Within this larger literature is a rapidly growing literature on the associations among religiousness/spirituality, COVID-19 impact, symptoms and well-being. Largely absent from this literature is a specific research focus on psychotherapy clients, and the influence of religiousness/spirituality and COVID-19 impact on change during treatment. One prominent theory in the existing literature centers on the notion that religiousness/spirituality is a coping resource for individuals during times of adversity. Yet, existing empirical findings present mixed evidence for the religious/spiritual coping hypothesis. We expanded upon these emerging research trends to examine the influence of religious/spiritual struggles, religious/spiritual commitment, religious/spiritual exploration, and COVID-19 impact ratings on psychotherapy change in a sample of adult clients (N = 185; Mage = 38.06; SD = 15.78; range = 19–81; 61.1% female; 69.7% White). The results of latent trajectory analysis identified three subgroups that differed on initial levels of symptoms and well-being and the nature of change over three time points. The COVID-19 impact ratings predicted change trajectories. As more positive ratings of COVID-19 impact increased, membership in the no change trajectory was more likely relative to the deterioration trajectory at high levels of both religious/spiritual commitment and exploration. The implications emphasize the need for judicious assessment of religiousness/spirituality and COVID-19 impact before integrating religiousness/spirituality into treatment.
Interfaith/Interreligious? Worship/Prayer? Services/Occasions? Interfaith Prayer Gatherings
Authors: Black Kathleen Mary
Published: May 2022

Today there are many occasions when persons from various religious traditions gather together for some type of observance. These gatherings are referred to by various names: Interfaith “Worship”, Multireligious “Prayer,” Interreligious “Services,” and “Integrative Religious Prayer.” People come together to learn more about one another, to protest injustices, to mourn disasters, and to join together to work for the common good. In some gatherings, there are also people in attendance who claim no religious affiliation at all. In other gatherings, like a community ritual event designed by the religious leaders of the town the eve before Thanksgiving, there is often an assumption that all who attend “pray” to a “God” even if the content and forms of “prayer” and the names and understandings of “God” differ. However, while Buddhists use the term “prayer,” they do not have a “god” to whom they pray. This article addresses the models of host/guest, serial interfaith occasions (when people are participant observers at a gathering where each religious tradition maintains its own integrity and contributes something to the whole in a serial fashion), and “inter-riting” (when the event is designed so the people can pray together in a unified fashion, often blurring the boundaries that commonly separate each religion). The Shinnyo Lantern Floating Hawaii, a large Buddhist-designed interfaith ritual gathering that combines the personal and the global, and offers insights into guest/host, serial interfaith, and inter-riting models, will be used as a basis for understanding these issues to assist religious leaders in their interfaith work.
Japan, Religion, History, Nation
Authors: Fitzgerald Timothy
Published: May 2022

I connect the invention of Japanese ‘religion’ since the Meiji era (1868–1912) with the invention of other modern imaginaries, particularly the Japanese Nation State and Japanese History. The invention of these powerful fictions in Japan was a specific, localised example of a global process. The real significance of this idea that religion has always existed in all times and places is that it normalises the idea of the non-religious secular as the arena of universal reason and progress. The invention of Japanese ‘religion’ had—and still has—a significant function in the wider, global context of colonial capital and the continual search for new ‘investment’ opportunities. Meiji Japan illustrates, in fascinating detail, a process of cognitive hegemony, and the way a globalising discourse on ‘progress’ transformed the plunder of colonial sites into a civilising mission. The idea that there is a universal type of practice, belief or institution called ‘religion’ as distinct from government, ‘politics’ or ‘science’ was not only new to Japan. It hardly existed in England or more widely in Protestant Europe and North America until the eighteenth or even 19th century. The idea of a secular constitutional nation state was only emergent in the late 18th century with the Declaration of Independence and the US Constitution. Most of Europe—including the colonial powers England and France—were still Christian confessional church states through most of the 19th century. The franchise was granted only to Christian men of substantial property, and denied to women, servants, wage labour, colonised subjects, and slaves. This critical, deconstructive narrative helps us to see more clearly the ideological function of the generic category of religion in the wider configuration of modern secular categories such as constitutional nation state, political economy, nature, history, and science. I also discuss the relation between History as a secular academic science, and the invention of ‘the Past’ in universal Time. I argue here that the invention of the Past by professional Historians has a significant role in transforming modern inventions such as ‘religion’ and the secular categories into the inherent and universal order of things, as though they have always been everywhere. I reveal this on-going process of ideological reproduction by close readings of some recent ‘histories of Japan’ and the way they uncritically construct ‘the Past’ in the terms of contemporary configurations.
“He Just Wanted Me to Do What Was Best for Me”: Latter-Day Saint Clergy’s Counsel to Sexual and Gender Minorities and Its Impact
Authors: Lefevor G. Tyler , Perez-Figueroa Adlyn M. , Skidmore Samuel J. , Gonzalez Kirsten A.
Published: May 2022

The purpose of this study was to understand counsel given to sexual and gender minority individuals by clergy in the Church of Jesus Christ of Latter-day Saints (CJCLDS), the impact of that counsel, and individuals’ perceptions of meetings with clergy. Twenty-five current and former members of the CJCLDS who identify as sexual and gender minorities (SGM) participated in 30–60 min semi-structured interviews focused on their interactions with clergy in the CJCLDS. Participants reported receiving various forms of counsel, including encouragement to adhere to church doctrine, counsel focused on self-acceptance, messages that clergy would support congregants’ agency and self-determination, counsel focused on increasing faith, and no answers. Participants reported a variety of perceptions of meetings with clergy including wishing clergy were more educated on the experiences of SGMs, hurtful experiences, expectations of mistreatment, recognition that clergy are doing their best, and gratitude for clergy. Interactions with clergy had long-lasting and far-reaching consequences including loss of trust in religious leaders, restriction of church membership, disengagement from faith, engagement with faith, nuanced or lost beliefs, and impacts on mental health. Results suggest that Latter-day Saints clergy working with SGM individuals may be experienced as most effective when they provide safe and supportive spaces for congregants to share their experiences, use approaches that focus on self-determination and agency, seek education/training from CJCLDS-specific LGBTQ+ organizations, and recognize that many SGM congregants approach interactions with clergy with trepidation and fears of mistreatment.
“The Light That Shineth in the Darkness”: Anglo-American Rural Missionaries and the Cuban Revolution
Authors: Finesurrey Samuel
Published: May 2022

Though rural Protestant missionaries stationed in Cuba routinely reproduced Anglo-American epistemologies and values, often in the service of US corporations, they also worked alongside their parishioners to challenge state and economic violence, as well as break the cyclical nature of Cuban poverty. Shared struggle with Cubans against Fulgencio Batista’s dictatorship proved transformative for many rural missionaries who, in the late 1950s, developed a revolutionary consciousness born through transnational solidarity. Missionaries challenged the dominant narrative coming from the US government and foreign corporations, as the Revolution pursued an increasingly anti-imperial and anti-capitalist agenda after Batista entered exile. While corporate executives and government officials from North America and Europe feared the new government, rural missionaries, often funded by these same corporations, defended the structural changes taking place after 1959. Through oral history and archival research, this article exposes how Cuban Protestants proved particularly influential in shaping the lens by which foreign missionaries came to understand, appreciate, and ultimately support the Cuban Revolution.
The Interplay of Leverage, Financing Constraints and Real Earnings Management: A Panel Data Approach
Authors: Hussain Ammar , Akbar Minhas , Khan Muhmmad Kaleem , Sokolová Marcela , Akbar Ahsan
Published: May 2022

Organizations are formed to gain long-term benefits. However, sometimes myopic management for feigned value enhancement led to the early demise of the firm. Further, to the best of our knowledge empirical role of financing constraints has not yet been explored between the relationship of leverage and earnings management practices. Therefore, the present study aims to empirically examine the impact of leverage on Real Earnings Management (REM) practices and how financing constraints influence this association. Employs a panel dataset of 3250 non-financial Chinese listed firms for a time period spanning from 2009 to 2018. Leverage is categorized into short-term, long-term, and total leverage to check the individual effects of each leverage category on REM practices. The data were analyzed through panel data fixed-effects and random-effects techniques as an econometric approach. First, consistent with positive accounting theory, the impact of total leverage on REM is positive. Second, compared to the long-term leverage, short-term leverage has more pronounced effects on managers’ opportunistic behavior towards using REM. Third, the influence of total leverage is higher (lower) on REM practices in financially unconstrained (constrained) firms. Fourth, the influence of short-term leverage on REM practices compared to long-term leverage is also weak in the financially constrained firms. These findings imply that, to avoid the consequences of managerial myopia, investors should abstain to invest in the firms that use higher amount of short-term debt and are financially unconstrained. This study is the first research to examine the impact of different leverage categories on REM practices in an emerging market, i.e., China, where the legal and financial structure is much poor.
Tracking the Early Movements of Northeast China Cold Vortices Using FY-3D MWTS-2 Observations of Brightness Temperature
Authors: Liu Hui , Zou Xiaolei
Published: May 2022

The Northeast China cold vortex (NCCV) often occurs in spring and summer, causing extreme weather such as rainstorm and hail in Northeast China. The brightness temperature (TB) observations of Microwave Temperature Sounder-2 (MWTS-2) on board Fengyun-3D (FY-3D), which can provide atmospheric temperature in various vertical layers, are firstly limb-corrected and then applied to track the origin and movement of four NCCV cases in June and July 2019. Results show that a cold core is observed at the location of NCCVs in TB observations of channels 4 and 5, whose peak weighting function (WF) altitudes are 700 and 400 hPa, respectively, indicating the cold structure of NCCVs in the middle and lower troposphere. The TB observations of channels 6 and 7, which measure the atmospheric temperature around 250 and 200 hPa, respectively, capture a warm core structure of NCCVs in the upper troposphere and lower stratosphere. Being less affected by the low-level cloud and rain, TB observations of channels 6 and 7 are applied to identify and track the warm cores of NCCVs. The NCCV tracks of movement identified by MWTS-2 observations compare well with those determined by the 500 hPa geopotential height and the 300 hPa potential vorticity (PV) anomaly from the ERA5 reanalysis. Both clearly show that the NCCVs were originated from high latitudes, then moved southeastward, and finally entered Northeast China. The entire process took several days. Therefore, TB observations of MWTS-2 can be used to identify the precursors of NCCVs and monitor their appearances, developments, and movements in time. With the flourishing development of Fengyun satellite series in China as well as the already existing 40 years of microwave sounder observations worldwide, this research provides a new way to investigate the synoptic and climatological features of NCCVs.
Estimation and Spatio-Temporal Change Analysis of NPP in Subtropical Forests: A Case Study of Shaoguan, Guangdong, China
Authors: Li Tao , Li Mingyang , Ren Fang , Tian Lei
Published: May 2022

Exploring the spatial and temporal dynamic characteristics of regional forest net primary productivity (NPP) in the context of global climate change can not only provide a theoretical basis for terrestrial carbon cycle studies, but also provide data support for medium- and long-term sustainable management planning of regional forests. In this study, we took Shaoguan City, Guangdong Province, China as the study area, and used Landsat images and National Forest Continuous Inventory (NFCI) data in the corresponding years as the main data sources. Random forest (RF), multiple linear regression (MLR), and BP neural network were the three models applied to estimate forest NPP in the study area. Theil–Sen estimation, Mann–Kendall trend analysis and the standard deviation ellipse (SDE) were chosen to analyze the spatial and temporal dynamic characteristics of NPP, whereas structural equation modeling (SEM) was used to analyze the driving factors of NPP changes. The results show that the performance of the RF model is better than the MLR and BP neural network models. The NPP in the study area showed an increasing trend, as the NPP was 5.66 t·hm−2·a−1, 7.68 t·hm−2·a−1, 8.17 t·hm−2·a−1, 8.25 t·hm−2·a−1, and 10.52 t·hm−2·a−1 in 1997, 2002, 2007, 2012, and 2017, respectively. Spatial aggregation of NPP was increased in the period of 1997–2017, and the center shifted from the mid-west to the southwest. In addition, the forest stand factors had the greatest effect on NPP in the study area. The forest stand factors and environmental factors had a positive effect on NPP, and understory factors had a negative effect. Overall, although forest NPP has fluctuated due to the changes of forestry policies and human activities, forest NPP in Shaoguan has been increasing. In the future, the growth potential of NPP in Shaoguan City can be further increased by continuously expanding the area proportion of mixed forests and rationalizing the forest age group structure.
Evaluation of the Moso Bamboo Age Determination Based on Laser Echo Intensity
Authors: Xu Wenbing , Fang Zihao , Fan Suying , Deng Susu
Published: May 2022

Determination of bamboo age is an important task for bamboo forest management and bamboo utilization. However, the bamboo age is usually manually determined in the field, which is time-consuming and labor-intensive. Due to the ability to generate very high-density point clouds, terrestrial laser scanning (TLS) has been applied in forestry to acquire forest parameters. This study evaluated the potential of using the laser echo intensity data generated by TLS technology to determine the Moso bamboo age represented by “du.” The intensity data were first corrected for the distance and incidence angle effects using an intensity correction method that constructed an empirical correction model by fitting piecewise polynomials to the intensity data collected based on a reference target. Then the models expressing the relationship between intensity and bamboo culm section number were constructed for different bamboo du by fitting polynomials to the intensity data of individual bamboo culms through least-squares adjustment. For a bamboo plant whose age is determined, the bamboo du could be determined based on the constructed intensity-culm section models. The proposed bamboo age determination method was tested at a site in a managed Moso bamboo forest in Lin’an District, Hangzhou City, Zhejiang Province, China. From the test site, 56 and 120 bamboo plants with known bamboo ages were selected to construct the intensity-culm section models and to validate the bamboo age determination method, respectively. The bamboo age determination accuracies for each bamboo du were all above 90%. The result indicates a great potential for automatic determination of bamboo age in practice using TLS technology.
September 2017 Solar Flares Effect on the Middle Atmosphere
Authors: Pikulina Polina , Mironova Irina , Rozanov Eugene , Karagodin Arseniy
Published: May 2022

This paper examines the response of the upper atmosphere to increased radiation following exceptional solar activity in September 2017. The active region of the Sun AR2673 has caused intense solar-terrestrial disturbance. This active region has generated several powerful X-class solar flares. The strongest outburst of the 24th solar activity cycle X9.3 occurred on 6 September 2017. The second powerful solar flare X8.2 occurred on 10 September 2017. Both flares caused an increase of the solar irradiance in extreme ultraviolet and soft X-ray spectral regions, and Ly-α line. The empirical FISM2 model was used to obtain data on the radiation fluxes from solar flares. The HAMMONIA chemistry–climate model was used to analyze the effect of radiation on the neutral atmosphere. This work presents the results of the effect of solar flares on the chemical composition and ozone of the upper and middle atmosphere.
A Satellite-Observed Substantial Decrease in Multiyear Ice Area Export through the Fram Strait over the Last Decade
Authors: Wang Yunhe , Bi Haibo , Liang Yu
Published: May 2022

Revealing the changes in the Fram Strait (FS) multiyear ice (MYI) export is crucial due to their climate relevance in the context of the loss rate of MYI being faster than that of the total ice in the Arctic. Here, we estimated winter (October–April) MYI area export through the FS over the last 2 decades by using updated MYI concentration data retrieved from active and passive microwave satellite observations. We divided the period into two regimes relative to the ice index: D1 (2002/03–2010/11) and D2 (2012/13–2019/20). The observed variations of winter MYI exports D2 were compared with those of the previous decade D1. The results show that the MYI area exports display strong interannual variability. A significant decrease in MYI export for the periods between D1 and D2 is noted. On average, the wintertime MYI area exports declined sharply by 22% from 3.82 × 105 km2 in D1 to 3.00 × 105 km2 in D2. In addition, the percentage of MYI in the total sea ice outflow through the FS (PCM) also decreased distinctly from 72% in D1 to 59% in D2. Statistics show that weekly sea ice drift across the strait can explain 76% of the MYI area export variability. Furthermore, the dominant atmospheric drivers contributing to the decline in MYI area export during D2 were examined. In the last decade (D2), the strengthened low pressure in the North Atlantic sector, combined with an eastward shift in the axis of dipole anomaly (DA), resulted in reduced MYI advection from the Beaufort Sea and Siberian Coast toward the FS. Moreover, weakened cyclonic activity south of the FS also contributed to the reduction in MYI export during D2.
Analysis of Transmission Depth and Photon Number in Monte Carlo Simulation for Underwater Laser Transmission
Authors: He Yuntao , Liu Yongjun , Liu Chang , Li Duan
Published: May 2022

The modeling of laser transmission characteristics in complex seawater is fundamental for bathymetric and oceanographic laser detection systems. Because the factors affecting laser transmission in seawater are independent of one another, firstly, in this paper, a Monte Carlo model of laser propagation in seawaters with suspended matter was established to study the influence of suspended matter with specific radius on the underwater laser transmission. Secondly, the influence of transmission depth and the number of photons on the laser extinction coefficients of seawater containing different concentrations of suspended matter were analyzed, respectively. Thirdly, the relationships between maximum transmission depth, the number of initial photons, and the concentrations were built and verified by simulations. Lastly, an experimental platform was set up and experiments were carried out to verify the Monte Carlo model and the relationships. Results show that (1) both the minimum initial photon number and maximum transmission depth depend exponentially on the concentrations of the suspended matter; (2) the extinction coefficients obtained by the Monte Carlo model and those obtained by experiments are consistent. The absolute values of the differences are less than 0.028 m−1, implying that (1) the proposed Monte Carlo model is effective for simulating laser propagation in seawaters with suspended matter; (2) the established relationships between maximum transmission depth, the minimum initial photon number, and the concentrations of suspended matter have better accuracies, which are valuable for the simulations on attenuation of laser transmission in seawater. The method of this paper can also be extended to the study of suspended solids with other radii and improve the simulation accuracy and decrease simulation time consumption.
In-Motion Alignment Method of SINS Based on Improved Kalman Filter under Geographic Latitude Uncertainty
Authors: Sun Jin , Ye Qianqi , Lei Yue
Published: May 2022

To realize the in-motion alignment of the strapdown inertial navigation system (SINS) under the geographic latitude uncertainty, we propose a latitude estimation and in-motion alignment method based on the integral dynamic window and polynomial fitting (IDW-PF) and improved Kalman filter (IKF). First, the integral dynamic window (IDW) is designed to smooth out the high-frequency line motion interference and accelerometer noise. Second, the specific force integral is performed for a cubic polynomial fitting (PF) with time as an independent variable to further suppress the line motion interference. Simultaneously, the latitude is estimated according to the geometric relationship between the angle of the gravitational acceleration vectors at different moments and the latitude. Finally, the IKF based on the multi-fading factor is designed for the in-motion alignment of SINS. A simulation experiment is conducted to verify the proposed latitude estimation and in-motion alignment method. The results indicate that the latitude can be estimated well by the method based on the IDW-PF; the mean and standard deviation of the estimated latitude can achieve −0.016° and 0.013° within 300 s. The trapezoidal maneuvering path is optimal when IKF is used, the pitch error is 0.0002°, the roll error is 0.0009° and the heading error is −0.0047° after the alignment ends at 900 s.
Perception-Aware Planning for Active SLAM in Dynamic Environments
Authors: Zhao Yao , Xiong Zhi , Zhou Shuailin , Wang Jingqi , Zhang Ling , Campoy Pascual
Published: May 2022

This paper presents a perception-aware path planner for active SLAM in dynamic environments using micro-aerial vehicles (MAV). The “Next-Best-View” planner (NBVP planner) is combined with an active loop closing, which is called the Active Loop Closing Planner (ALCP planner). The planner is proposed to avoid both static and dynamic obstacles in unknown environments while reducing the uncertainty of the SLAM system and further improving the accuracy of localization. First, the receding horizon strategy is adopted to find the next waypoint. The cost function that combines the exploration gain and the loop closing gain is designed. The former can reduce the mapping uncertainty, while the latter takes the loop closing possibility into consideration. Second, a key waypoint selection strategy is designed. The selected key waypoints, instead of all waypoints, are treated as potential loop-closing points to make the algorithm more efficient. Moreover, a fuzzy RRT-based dynamic obstacle avoidance algorithm is adopted to realize obstacle avoidance in dynamic environments. Simulations in different challenging scenarios are conducted to verify the effectiveness of the proposed algorithm.
The Analysis of Cones within the Tianwen-1 Landing Area
Authors: Huang Hai , Liu Jianjun , Wang Xing , Chen Yuan , Zhang Qing , Liu Dawei , Yan Wei , Ren Xin
Published: May 2022

On 15 May 2021, the Zhurong rover of China’s first Mars mission, Tianwen-1 (TW-1), successfully landed in southern Utopia Planitia on Mars. Various landforms were present in the landing area, and this area recorded a complex geological history. Cones are one of the typical landforms in the landing area and Utopia Planitia, and they have a great significance to the local geological processes due to the diversity of their origins. Using High-Resolution Imaging Camera (HiRIC) images collected by the TW-1 orbiter, we identified a total of 272 well-preserved circular cones in the landing area. Detailed surveys of their spatial distribution, morphological characteristics, and morphometric parameters were conducted. A preliminary analysis of the surface characteristics of these cones also provides additional information to strengthen our understanding of them. The results of the high-resolution topographic analysis show that the cone heights are in the range of 10.5–90.8 m and their basal diameters range from 178.9–1206.6 m. We compared the morphometric parameters of the cones in the landing area with terrestrial and Martian analogous features and found that our measured cones are consistent with the ranges of mud volcanoes and also a small subset of igneous origin cones. However, the result of spatial analysis is more favorable to mud volcanoes, and the lower thermal inertia of the cones in the landing area compared to their surrounding materials is also a typical characteristic of mud volcanoes. Based on current evidence and analysis, we favor interpreting the cones in the TW-1 landing area as mud volcanoes.
MIMO FMCW Radar with Doppler-Insensitive Polyphase Codes
Authors: Kim EunHee
Published: May 2022

Co-located MIMO is used to enlarge the antenna aperture virtually and increase the angular resolution. This paper shows FMCW radar using MIMO VAA. Polyphase codes are designed for modulating the successive chirps of transmitting signals. The codes are optimized to have low cross-correlations regardless of the Doppler filter mismatch. Compared with orthogonal codes, the designed codes show robust performance for Doppler mismatch and lower angle estimation errors. The entire procedure is explained, and the simulation results are provided.
New Insights into Ice Avalanche-Induced Debris Flows in Southeastern Tibet Using SAR Technology
Authors: Luo Siyuan , Xiong Junnan , Liu Shuang , Hu Kaiheng , Cheng Weiming , Liu Jun , He Yufeng , Sun Huaizhang , Cui Xingjie , Wang Xin
Published: May 2022

Drastic climate change has led to glacier retreat in southeastern Tibet, and the increased frequency and magnitude of heavy rainfall and intense snow melting have intensified the risk of ice avalanche-induced debris flows in this region. To prevent and mitigate such hazards, it is important to derive the pre-disaster evolutionary characteristics of glacial debris flows and understand their triggering mechanisms. However, ice avalanche-induced debris flows mostly occur in remote alpine mountainous areas that are hard for humans to reach, which makes it extremely difficult to conduct continuous ground surveys and optical remote sensing monitoring. To this end, synthetic aperture radar (SAR) images were used in this study to detect and analyze the pre-disaster deformation characteristics and spatial evolution in the Sedongpu Basin and to detect changes in the snowmelt in the basin in order to improve our understanding of the triggering mechanism of the ice avalanche-induced debris flows in this region. The results revealed that the maximum average deformation rate in the basin reached 57.3 mm/year during the monitoring period from January 2016 to October 2018. The deformation displacement in the gully where the ice avalanche source area was located was intimately correlated with the summer snowmelt and rainfall and was characterized by seasonal accumulation. Clear acceleration of the deformation was detected after both the most recent earthquake and the strong rainfall and snowmelt processes in the summer of 2018. This suggests that earthquakes, snowmelt, and rainfall were significant triggers of the Sedongpu ice avalanche-induced debris flows. The results of this study provide new insights into the genesis of the Sedongpu ice avalanche-induced debris flows, which could assist in disaster warning and prevention in alpine mountain regions.