bluuebunny/crossref_metadata_2025 huggingface dataset:
Simplified dynamical model and experimental verification of an underwater hydraulic soft robotic arm
Authors: Xie Qing , Wang Tao , Zhu Shiqiang
Published: May 2022

Inherent compliance equips soft robotic arms with such advantages as incomparable flexibility, good adaptability, and safe interaction with the environment, etc. However, the strong nonlinearity also brings challenges to predict their dynamic behaviors. This work presents a simplified dynamic model of an underwater soft robotic arm which has three fiber-reinforced hydraulic chambers distributed symmetrically in each section. By controlling the pressures in the chambers, the soft robotic arm can perform complex spatial motion with multiple degrees of freedom. The model is based on Lagrangian method and piecewise constant curvature hypothesis, and considers the nonlinear viscoelasticity of soft material. The model accuracy is verified by the experiments of a two-section soft robotic arm with different actuation modes. The effects of geometrical features on dynamic response are also investigated through model-based simulation and test verification, which can provide guidance to parameter optimization. The proposed dynamic model can be extended to multiple sections and contribute to behavior analysis, performance prediction, and motion control of the soft robotic arm.
Cubic nonlinearity driven dust ion acoustic solitons with superthermal two-temperature electrons in the Saturn’s magnetosphere
Authors: Nawaz H , Jahangir R , Masood W , Siddiq M
Published: May 2022

Nonlinear propagation of electrostatic waves with cubic nonlinearity has been investigated in a multicomponent dusty plasma with inertial ions, superthermal two temperature electrons and stationary dust. In this regard, single and multi-soliton solutions of modified Korteweg–de Vries (mKdV) equation for dust ion acoustic waves (DIAWs) have been investigated implementing Hirota’s bilinear method. Plasma parameters affecting the amplitude of dust ion acoustic (DIA) mKdV single soliton have been thoroughly investigated based on the data from Saturn’s magnetosphere. The overtaking interaction of two mKdV solitons has been investigated by changing the percentage of propagation vectors to observe bipolar structure reducing to a single humped structure for a particular value of the ratio of propagation vectors. The most significant outcome of this study has been the investigation of interaction of a compressive and rarefactive dust ion acoustic soliton forming a peculiar composite shape at the interaction point.
Non-asymptotically flat Einstein-Scalar black hole
Authors: Mazharimousavi S Habib
Published: May 2022

Exact solutions in general relativity and other theories in physics are important. One of such theories is the Einstein-Scalar theory. We present an exact class of solutions in the Einstein-Scalar theory with a specific nonlinear self-interacting potential. The potential admits a local minimum and a local maximum in general configuration. The solutions include AdS and dS black hole and non-black hole spacetimes. The scalar field is regular on and outside the horizon and asymptotically vanishes when

r
→
∞
.

We also study the thermal stability of the black hole solution and it is shown that the black hole is thermally stable for a certain interval of the radius of the horizon.
Spatiotemporal feedforward between PKM2 tetramers and mTORC1 prompts mTORC1 activation
Authors: Xia Yu , Wang Shuming , Song Chunbo , Luo Ruo-yu
Published: May 2022

Most mammalian cells couple glucose availability to anabolic processes via the mTORC1 pathway. However, the mechanism by which fluctuations in glucose availability are rapidly translated into mTORC1 signals remains elusive. Here, we show that cells rapidly respond to changes in glucose availability through the spatial coupling of mTORC1 and tetramers of the key glycolytic enzyme pyruvate kinase M2 (PKM2) on lysosomal surfaces in the late G1/S phases. The lysosomal localization of PKM2 tetramers enables rapid increases in local ATP concentrations around lysosomes to activate mTORC1, while bypassing the need to elevate global ATP levels in the entire cell. In essence, this spatial coupling establishes a feedforward loop to enable mTORC1 to rapidly sense and respond to changes in glucose availability. We further demonstrate that this mechanism ensures robust cell proliferation upon fluctuating glucose availability. Thus, we present mechanistic insights into the rapid response of the mTORC1 pathway to changes in glucose availability. The underlying mechanism may be applicable to the control of other cellular processes.
Potential pollution of the K
π-puzzle by the isospin-breaking π
0-η-η' mixing effect *
Authors: Zhang Zhen-Hua
Published: May 2022

The influence of the isospin-breaking

mixing effect on the

-asymmetries of

processes is examined for the first time. It is found that this mixing effect presents significant uncertainty for both the

-asymmetry sum rule of

processes and the

-asymmetry difference of

and

, potentially obscuring the significance of the

-puzzle. As the correction caused by the

mixing effect is highly dependent on four strong non-perturbative phases, a definitive conclusion is currently unavailable.
Variations in summertime compound heat extremes and their connections to urbanization in China during 1980–2020
Authors: Yang Yang , Zhao Na , Wang Yuwei , Chen Mingxing
Published: May 2022

Summertime heat extremes are exceptionally harmful and destructive to human health and socio-economic systems. Based on 2419 meteorological stations, this study investigates the temporal and spatial characteristics of summertime extreme high temperatures across China and their response to urbanization over the period 1980–2020. The results show that (a) both the maximum temperature (TXx) and minimum temperature (TNn) in the summer have shown an upward trend in most parts of China during the past 40 years; significant upward trends are found in eastern China for independent hot days (IHDs), independent hot nights (IHNs) and compound hot events (CHE). (b) Extreme heat shows a positive spatial clustering pattern across China. The hot spots of the three compound heat events (including IHD, IHN and CHE) are mainly distributed in the north; while the cold spots are roughly distributed in the south. The spatial pattern of hot and cold spots of TXx exhibits an east-west orientation while that of TNn shows a southeast-northwest orientation. (c) The correlation between the heat extremes and urbanization level varies among regions, with most exhibiting linear and exponential relationships. Significant urbanization effects on TXx and TNn are detected in all sub-regions, with contributions ranging from 11% to 41% and 14% to 29%, respectively, while urbanization contributions to the three compound heat events vary significantly among the sub-regions. Our findings present the spatio–temporal patterns of summertime heat extremes, especially the spatial clustering pattern of the compound extremes, and thus enrich the understanding of these variations and their regional response to urbanization, which may have important implications for policy-making among distinct sub-regions.
Regional projection of climate warming effects on coastal seas in east China
Authors: Zhang Wenxia , Dunne John P , Wu Hui , Zhou Feng
Published: May 2022

The coastal region in east China experiences massive anthropogenic eutrophication, and the bottom water off the Changjiang River Estuary in the East China Sea faces the threat of severe seasonal hypoxia. We find that projected future climate changes will work in parallel with anthropogenic eutrophication to exacerbate current hypoxia and increase shelf vulnerability to bottom hypoxia. We use a coupled physical-biogeochemical regional model to investigate the differences of shelf hydrography and oxygen dynamics between present and future projected states. Model results indicate that the Yellow Sea Cold Water Mass which plays essential roles in nekton migration and shellfish farming practically disappears by the end of the 21st century, and shelf vertical stratification strengthens by an average of 12.7%. Hypoxia off the Changjiang River Estuary is exacerbated with increased (by one month) hypoxia duration, lower dissolved oxygen minima, and significant lateral (202%) and vertical (60%) expansions of hypoxic water. Reduced oxygen solubility, and accelerated oxygen consumption under increased primary production and rising water temperature contribute 42% and 58%, respectively, of bottom dissolved oxygen decrease in the East China Sea. Model results also show increased vertical diffusion of oxygen, despite vertical stratification strengthening, due to increased surface-bottom oxygen concentration gradient associated with increased oxygen release in surface water and exacerbated oxygen consumption in subsurface water.
Universality of the fully connected vertex in Laplacian continuous-time quantum walk problems
Authors: Razzoli Luca , Bordone Paolo , Paris Matteo G A
Published: May 2022

A fully connected vertex w in a simple graph G of order N is a vertex connected to all the other N − 1 vertices. Upon denoting by L the Laplacian matrix of the graph, we prove that the continuous-time quantum walk (CTQW)—with Hamiltonian H = γL—of a walker initially localized at |w⟩ does not depend on the graph G. We also prove that for any Grover-like CTQW—with Hamiltonian H = γL + ∑
w

λ

w
|w⟩⟨w|—the probability amplitude at the fully connected marked vertices w does not depend on G. The result does not hold for CTQW with Hamiltonian H = γA (adjacency matrix). We apply our results to spatial search and quantum transport for single and multiple fully connected marked vertices, proving that CTQWs on any graph G inherit the properties already known for the complete graph of the same order, including the optimality of the spatial search. Our results provide a unified framework for several partial results already reported in literature for fully connected vertices, such as the equivalence of CTQW and of spatial search for the central vertex of the star and wheel graph, and any vertex of the complete graph.
Investigation of complex-energy shift in time-dependent perturbed decaying systems
Authors: Szilvási Réka , Kis Dániel P
Published: May 2022

In this paper a wavefunction-centered description of decaying states that are coupled to an external potential of general time-dependence is investigated. We present the application of non-Hermitian spectral calculations merged with the (t, t′)-formalism to estimate the possible time-dependent potential induced corrections to the lifetime of quasi-stationary states. The appliance of the formalism is demonstrated on some specific potential models as illustrative examples that represent decaying systems. We argue, that the presented framework and computational technique might provide a way to evaluate the lifetime of quasi-stationary states of different types of physical decaying systems that are subjected to perturbative, time-dependent drivings.
Effects of mentoring housewives assistance on the ability to sort waste in sub-district of Panakukkang, Makassar
Authors: Nurleli  , Syatriani Sri , Fauziah Sri
Published: May 2022

Waste sorting is separating one type of waste from another. In 2016, the amount of waste in Makassar reached 4,183.41 m3/day, while the amount handled was 3,962.63 m3/day. This study was conducted in 53 families of Sinrijala Village, Panakukkang District, Makassar with 48 housewives in order to evaluate the effects of mentoring housewives on the ability to sort waste using quasi-experimental research with a pretest-posttest non-randomized control group design. The results before mentoring showed that, in the experimental group, there was one respondent (4.20%) who sorted waste, while 23 respondents (95.80%) did not sort the waste. In the control group, there were two housewives (8.30%) who sorted the waste in contrast to 22 respondents (91.70%) who had never sorted the waste before. After being guided, 10 respondents of the experiment group (41.70%) sorted the waste. In the control group, two respondents (8.30%) sorted the waste. Statistical test obtained Z = -3000 and p-value of 0.003. Therefore, it is concluded that there is an effect of mentoring on waste sorting. For further studies, it is recommended to study the practice of recycling waste into goods of economic value.
Hazard risk identification from the used masks in Jabodetabek
Authors: Simatupang M M , Veronika E
Published: May 2022

COVID-19 has brought many changes of lifestyle to people around the world. The obligation to use masks as an effort to prevent the transmission of COVID-19 is such an example. This policy led to the increase of masks using in the general population. Some particular procedures of masks usage and used masks handling must be applied to prevent negative impacts. Many of these guidelines are not generally known. This study is carried out to determine the handling, cleaning, and disposal method of used masks at beginning of the pandemic. The research data were obtained from 152 random respondents who voluntarily filled out online questionnaires. Participants came from some areas in Jabodetabek that implemented Large-Scale Social Restrictions (PSBB) and were required to wear masks. Most of the respondents kept the used mask temporarily then reused it. Handling of the used masks, both surgical masks and cloth masks, was also showed poor sanitation for some participants. The waste generation from used surgical masks at the beginning of the pandemic was also quite alarming. Education on the handling method of used masks is important to be widely publicized to prevent potential hazards, such as the transmission of respiratory infections and environmental contamination risk.
The influence of decision making of farmers choosing rice varieties on rice productivity levels in Central Lampung Regency
Authors: Rangga K K , Yanfika H , Mangesti R A , Rudy  , Bursan R , Rahmat A , Adipathy D A
Published: May 2022

This study aims to determine the influence of decision making of farmers choosing rice varieties on rice productivity levels. The data analysis method used in this study is descriptive and quantitative analysis. This research was conducted in Bangun Rejo Subdistrict, Central Lampung Regency. The number of respondents in this study was 73 samples. The data used is primary and secondary data. The data analysis in this study was conducted with multiple linear regression tests. The results showed that the decision-making process of choosing rice varieties by farmers is done by considering several things, namely the suitability of varieties to the needs of farmers, the suitability of varieties with the experience of farmers, the level of complexity in the application of varieties, as well as the relative advantages of varieties. The decision-making of farmers choosing rice varieties positively affects 90.4 percent of rice productivity. The more appropriate farmers choose rice varieties that suit the needs, conditions of the land, type and intensity of pest attacks in the area, it will support the acquisition of high productivity.
Synergy between Disaster Preparedness Area program with local institutions for community disaster preparedness
Authors: Suradi  , Sumarno S , Sugiyanto  , Nainggolan T , Murni R , Erwinsyah RG , Andriyani L
Published: May 2022

The Government of Indonesia through Ministry of Social Affairs launched the Disaster Preparedness Area Program (Kawasan Siaga Bencana or KwSB) in 2019 to build community preparedness for natural disasters. This program is a forum for early community-based disaster management synergy with an integrated approach that involves various stakeholders in areas with high risk of natural disasters. Meanwhile social reality exposes that historically, people living in areas prone to natural disasters have had their own local institutions and knowledge on dealing with natural disasters. Several research results indicated there is a gap between the government programs and the social realities in society. Accordingly, this research will identify the consequences of the KwSB Program on existing local institutions in the community before this program was launched. That very problem is answered through qualitative approach with data collected from literature studies, observations, in-depth interviews, and Focus Group Discussions (FGDs). Furthermore, the collected texts and narratives are analyzed by categorization and then comparing the existence and actions of local institutions before and after the KwSB Program. The results show that there are consequences due to the presence of the program on the social reality of local institutions, especially in the reconfiguration of social networks in the community.
Slow rotation of a sphere about its diameter normal to two planes with slip surfaces
Authors: Liao Jun Q , Keh Huan J
Published: May 2022

The steady creeping flow of an incompressible Newtonian fluid around a slip spherical particle rotating about its diameter perpendicular to one or two slip plane walls is analyzed. To satisfy the Stokes equation for fluid velocity, the general solution consists of the sum of the essential solutions in spherical and cylindrical coordinates. Boundary conditions are implemented first on the plane walls by means of the Hankel transforms and then on the particle surface through a collocation method. The hydrodynamic torque exerted on the particle is obtained with excellent convergence for various values of the pertinent geometrical and stick-slip parameters, and the effect of the slip planes on the rotational motion of the slip particle is interesting. The torque increases with an increase in the stickiness of the walls from the limit of full slip to the limit of no slip. When the stick parameters of the plane walls are larger than some critical values, the hydrodynamic torque is more than that on an identical particle in the unbounded fluid and an increasing function of the stickiness of the particle surface and ratio of the particle radius to distance from the walls. When the stick parameters of the plane walls are smaller than the critical values, on the contrary, the torque is less than that on the particle in the unbounded fluid and a decreasing function of the surface stickiness and relative radius of the particle.
Property improvement of processed PLA/PBAT using chain extenders
Authors: Nekhamanurak Bawornkit
Published: May 2022

The polymer blend of poly(lactic acid)/poly(butylene adipate-co-terephthalate) (PLA/PBAT), commercially named Ecovio, is a biodegradable plastic with a high level of strength and toughness. Despite the development of biodegradable plastics with improved characteristics and greater applicability, their cost remains prohibitively high preventing their widespread use. One approach to reducing production costs is recycling manufactured waste plastics. However, in this process, the properties of plastic are typically changed due to chain scissions during thermal reprocessing. Using an additive such as a chain extender is thought to reconnect cleaved polymer chains. Therefore, the purpose of this research is to investigate the influences of two chain extenders, multifunctional epoxide and multifunctional imide, on the mechanical properties and thermal properties as well as the melt flow rate of Ecovio. Materials were processed and blended using a twin-screw extruder and formed into film samples via the blow film extrusion process. The findings revealed that the addition of chain extenders resulted in a higher viscosity of Ecovio. In the thermal properties test, it was found that the use of chain extenders resulted in shifts in the glass transition, crystallization, melting temperature, and thermal stability of Ecovio. Finally, the result of mechanical properties test illustrated that Young’s modulus and tensile strength of thermal processed Ecovio were changed and improved by blending with virgin Ecovio and chain extenders.
Divided-pulse nonlinear compression in a multipass cell
Authors: Stark Henning , Grebing Christian , Buldt Joachim , Klenke Arno , Limpert Jens
Published: May 2022

The pulse-energy and peak-power limitations of a gas-filled multipass cell (MPC) for nonlinear pulse compression are surpassed by applying a burst of four temporally separated pulses instead of a single one. The burst is generated by two birefringent crystals and contains

1

m
J

of energy per pulse replica. It is then spectrally broadened in an Argon-filled MPC and recombined into a single pulse by a second set of birefringent crystals. The combined pulse is compressed by chirped mirrors to a pulse duration of

32

f
s

and a pulse energy of

3.4

m
J

. An excellent passive stability and a high system efficiency of

>

90% are reached. Using the 4-pulse burst, the overall output energy supported by the MPC is doubled in comparison to single-pulse operation.
Physics-based compact modelling of the analog dynamics of HfO
x
resistive memories
Authors: Vaccaro F , Brivio S , Perotto S , Mauri A G , Spiga S
Published: May 2022

Resistive random access memories (RRAMs) constitute a class of memristive devices particularly appealing for bio-inspired computing schemes. In particular, the possibility of achieving analog control of the electrical conductivity of RRAM devices can be exploited to mimic the behaviour of biological synapses in neuromorphic systems. With a view to neuromorphic computing applications, it turns out to be crucial to guarantee some features, among which a detailed device characterization, a mathematical modelling comprehensive of all the key features of the device both in quasi-static and dynamic conditions, a description of the variability due to the inherently stochasticity of the processes involved in the switching transitions. In this paper, starting from experimental data, we provide a modelling and simulation framework to reproduce the operative analog behaviour of HfO
x
-based RRAM devices under train of programming pulses both in the analog and binary operation mode. To this aim, we have calibrated the model by using a single set of parameters for the quasi-static current–voltage characteristics as well as switching kinetics and device dynamics. The physics-based compact model here settled captures the difference between the SET and the RESET processes in the I–V characteristics, as well as the device memory window both for strong and weak programming conditions. Moreover, the model reproduces the correct slopes of the highly non-linear kinetics curves over several orders of magnitudes in time, and the dynamic device response including the inherent device variability.
Memristive devices based hardware for unlabeled data processing
Authors: Xiao Zhuojian , Yan Bonan , Zhang Teng , Huang Ru , Yang Yuchao
Published: May 2022

Unlabeled data processing is of great significance for artificial intelligence (AI), since well-structured labeled data are scarce in a majority of practical applications due to the high cost of human annotation of labeling data. Therefore, automatous analysis of unlabeled datasets is important, and relevant algorithms for processing unlabeled data, such as k-means clustering, restricted Boltzmann machine and locally competitive algorithms etc, play a critical role in the development of AI techniques. Memristive devices offer potential for power and time efficient implementation of unlabeled data processing due to their unique properties in neuromorphic and in-memory computing. This review provides an overview of the design principles and applications of memristive devices for various unlabeled data processing and cognitive AI tasks.
Ideals
Authors: Bonds Mark Evan
Published: May 2022

‘Ideals’ considers that ideals have a way of colliding with reality in every life. In Beethoven’s case, the distance between the two was more extreme than most, the collision more severe. His ideals—the principles by which he lived—grew out of a mixture of religious, ethical, and philosophical beliefs. His reality was the need to earn a living in a world of sound he was increasingly unable to hear. His correspondence, the Heiligenstadt Testament, and his diary all bear witness to a lifelong effort to articulate his vision of what he could become and what he could accomplish.
The music
Authors: Bonds Mark Evan
Published: May 2022

‘The music’ shows that Beethoven wrote in virtually every genre of his time: symphonies, concertos, overtures, sonatas of all kinds, trios, quartets, quintets, and larger chamber ensembles, songs, oratorio, opera, and sacred music. And while listeners today enjoy easy access to program notes that describe individual works in detail, broader perspectives can also help us understand the music at a still deeper level. This chapter examines Beethoven’s numbering of his publications (those with and without opus numbers), the implications of the descriptive titles he gave to some of his works, the question of whether instrumental music has “meaning” outside of itself, and the expectations listeners of his time would have had toward any of the genres in which he wrote.
Evangelicalism expands
Authors: Stackhouse John G.
Published: May 2022

‘Evangelicalism expands’ examines the expansion of evangelicalism in the nineteenth and twentieth centuries. It was the entrepreneurial Charles Grandison Finney who carried the bulk of evangelicalism with him: not only mass evangelists, but the twentieth-century church growth movement, the booming megachurches, and other approaches to evangelism based on the social science of missiology. Revivals would continue to break out regionally over the nineteenth and twentieth centuries in Greater Britain and America—and well beyond. It is worth also considering the coming of the denominational mission societies and “faith missions” and Evangelicals’ understanding of gender roles. Pentecostalism emerged in a major American city and soon went worldwide.
Inversion of large-scale gravity data with application of VNet
Authors: Huang R , Zhang Y , Vatankhah S , Liu S , Qi R
Published: May 2022

Inversion of large-scale gravity data set is generally a challenging problem due to memory requirements and computational costs. In this study, based on VNet, we present an efficient strategy for the large-scale gravity inverse problem by simultaneously tackling several base-scale gravity data. We first construct a large number of base-scale geological models including gravity sources, with different shapes and dimensions, and also their forward model data sets. Then, the idea of semantic segmentation is used to train an inversion network. In the next step, a finite number of base-scale and similar size area of gravity data, clipped from the original large data set with a fixed stride, are fed into the trained network. Finally, the individual recovered models are combined to provide the inversion result for the whole subsurface area. The feasibility and effectiveness of the presented inversion algorithm are tested on a large-scale complicated synthetic model. The algorithm is, then, verified for the inversion of the gravity data set obtained over the Morro do Engenho complex in central Brazil.
Enhancement of direct waves based on the probability density function of seismic wave amplitudes
Authors: Oshima Mitsutaka , Takenaka Hiroshi
Published: May 2022

The enhancement of direct waves in seismic records is desirable in various seismological situations, where the accurate picking of seismic phases is necessary for hypocentre location, spectral inversion, waveform inversion and seismic tomography. In this study, we developed a new method to enhance direct waves in seismic waveforms based on the statistical distribution (probability density function, PDF) of the amplitudes of waveforms. The seismic waveform changes from a direct wave to a coda wave as time proceeds, which also causes the PDF of its amplitude to vary with time. The PDF becomes similar to a Gaussian or Rayleigh distribution with time, and hence, direct waves can be enhanced using the dissimilarity between the PDF of the amplitude of the seismic waveform and the Gaussian or Rayleigh distribution. In the proposed method, the Kullback–Leibler divergence is used to measure dissimilarity and it is applied as a weight. We confirmed that the method can effectively enhance direct P and S waves by applying it to seismic records of the 2016 Kumamoto earthquake, synthetic waveforms with noise and volcanic events. The method was also applied to waveforms of the 2008 Iwate–Miyagi Nairiku earthquake, which revealed that direct waves were enhanced, and an overview of the wave field and rupture process was obtained. The proposed method can detect direct waves even from subevents, thereby producing detailed information on the earthquake rupture process. We detected two significant pulses and determined their source location and rupture times. The estimated pulse sources were consistent with parts of the rupture scenario proposed by the previous studies. In addition, for local and teleseismic event records, the proposed method was compared with other methods to study its merits and demerits. The present method can enhance seismic phases on records of local and teleseismic events. Our method detects or enhances direct waves based neither on their amplitudes nor on their temporal variations but on the statistical distribution of their amplitudes, which has both advantages and disadvantages. Although polarization filtering is a powerful method that can enhance seismic phases, it requires three-component waveforms. The proposed method can be applied even to a single component record, which is a significant advantage.
Kinematic Trajectories in Response to Speed Perturbations in Walking Suggest Modular Task-Level Control of Leg Angle and Length
Authors: Schwaner M J , Nishikawa K C , Daley M A
Published: May 2022

Navigating complex terrains requires dynamic interactions between the substrate, musculoskeletal, and sensorimotor systems. Current perturbation studies have mostly used visible terrain height perturbations, which do not allow us to distinguish among the neuromechanical contributions of feedforward control, feedback-mediated, and mechanical perturbation responses. Here, we use treadmill-belt speed perturbations to induce a targeted perturbation to foot speed only, and without terrain-induced changes in joint posture and leg loading at stance onset. Based on previous studies suggesting a proximo-distal gradient in neuromechanical control, we hypothesized that distal joints would exhibit larger changes in joint kinematics, compared to proximal joints. Additionally, we expected birds to use feedforward strategies to increase the intrinsic stability of gait. To test these hypotheses, seven adult guinea fowl were video recorded while walking on a motorized treadmill, during both steady and perturbed trials. Perturbations consisted of repeated exposures to a deceleration and acceleration of the treadmill-belt speed. Surprisingly, we found that joint angular trajectories and center of mass fluctuations remain very similar, despite substantial perturbation of foot velocity by the treadmill belt. Hip joint angular trajectories exhibit the largest changes, with the birds adopting a slightly more flexed position across all perturbed strides. Additionally, we observed increased stride duration across all strides, consistent with feedforward changes in the control strategy. The speed perturbations mainly influenced the timing of stance and swing, with the largest kinematic changes in the strides directly following a deceleration. Our findings do not support the general hypothesis of a proximo-distal gradient in joint control, as distal joint kinematics remain largely unchanged. Instead, we find that leg angular trajectory and the timing of stance and swing are most sensitive to this specific perturbation, and leg length actuation remains largely unchanged. Our results are consistent with modular task-level control of leg length and leg angle actuation, with different neuromechanical control and perturbation sensitivity in each actuation mode. Distal joints appear to be sensitive to changes in vertical loading but not foot fore-aft velocity. Future directions should include in vivo studies of muscle activation and force–length dynamics to provide more direct evidence of the sensorimotor control strategies for stability in response to belt-speed perturbations.
Wave velocity in shale in the Wufeng-Longmaxi formation in Sichuan Basin
Authors: Liu Zichun , Peng Rong , Li Xiangyang , Du Xiangdong , Zhu Zhenyu , Li Xin , Li Huafei
Published: May 2022

Analyzing the pattern of wave velocity is important for velocity prediction and amplitude-versus-offset analysis during unconventional seismic exploration. Several parameters, including the maturity and microstructure of organic matter (OM), the wave velocity, the mineral composition and the density of shale from Upper Ordovician Wufeng and Lower Silurian Longmaxi, formations were experimentally evaluated in this study. To investigate the factors influencing the wave velocity, the obtained data were analyzed together with numerical calculations and previous experimental results. A theoretical model of an anisotropic differential equivalent medium (DEM) was then established and the following conclusions were drawn: (i) different from Bakken shale, OM in the Wufeng-Longmaxi (WL) shale is over-mature and patchy, with higher elastic parameters for the kerogen; (ii) different from other areas, the amount of kerogen (being over-mature) in WL shale is not correlated with the wave velocity; (iii) bogenic quartz minerals were abundant in the tested samples, and their amount was positively correlated with OM, whereas OM was negatively correlated with the amount of clay; (iv) clay, quartz and kerogen contents had different association with the rock skeleton, resulting in a V-shaped relationship between the quartz content and wave impedance, with the slope of the growing branch being higher than that of the decreasing branch and (v) the anisotropic DEM model effectively proves the influence of OM maturity and patch shape on shale velocity. Also, the V-shaped relationship between quartz and wave impedance caused by skeleton change are verified. This study provides valuable data as well as a theoretical basis for seismic interpretations in the study area.
Crustal structures beneath the Northern Jiangsu Basin and its surrounding areas: implications for geothermal prospecting
Authors: He Kai , Huang Rong , Xu Yixian , Hu Shaoqian , Wei Penglong
Published: May 2022

Based on the recordings of 42 permanent seismic stations in Northern Jiangsu Basin (NJB) and its surrounding areas, we obtained both the sediment and crustal thickness in the region, using the nearest-neighbor algorithm and H–κ stacking method of receiver functions. We proposed a solution to use the sediment thickness to correct the depth of actual Moho discontinuity beneath the basin areas. Our results indicate that the sediment thickness in the northwest of the NJB is <1 km. We suggest that the southeastern border of the NJB should extend to the Yangzhou-Rudong area. The results of Moho variations show that the undulations of the Moho beneath the western NJB retains the traces of the sinistral shearing movement of the Tan-Lu Fault since the Miocene. Finally, we suggest the area around the Gaoyou city to be a prospective area for geothermal exploration.
Precise prediction of the collapse column based on channel wave spectral disparity characteristics and velocity tomography imaging
Authors: Wu Yanhui , Zhu Guowei , Wang Wei
Published: May 2022

Collapse columns are complex geological anomalies that present safety hazards in coal mines. In practice, the boundaries and internal features are difficult to finely characterize. In this study, we use the Jeffrey divergence to reveal the spectral disparity when the channel wave seismic ray path encounters a collapse column. We use the forward mode and applications for verification. We find that the centroid peak frequency shifts toward lower frequencies, the frequency band narrows and the rays through a collapse column cause attenuation of energy. When a seismic ray path encounters a large collapse column, no channel wave appears in the seismic record, the dispersion curve velocity is greater than the velocity of a normal coal seam, the centroid peak frequency drops and the frequency band shrinks. When a seismic ray passes through the boundary of a collapse column, the dispersion curve shows two parallel velocity phases. When a seismic ray path passes through a small collapse column, the decrease in the centroid frequency becomes the only identifying feature. The proposed channel wave spectral disparity characteristic and velocity tomography imaging method can effectively identify small collapse columns and improve the accuracy and precision of the location of collapse column boundaries, with a position deviation of less than 10 m.
Modified viscoelastic wavefield simulations in the time domain using the new fractional Laplacians
Authors: Zhang Yabing , Liu Yang , Zhu Hejun , Chen Tongjun , Li Juanjuan
Published: May 2022

Accurately characterizing seismic attenuation effects on wave propagations is crucially important for structure interpretation and reservoir evaluation. The conventional fractional viscoelastic wave equation is not satisfactory on accuracy for small Q values. To solve this issue, we derive a novel fractional viscoelastic wave equation by combining an accurate relationship between angular frequency and complex wavenumber. The dissipation- and dispersion-dominated wave equations are also derived to simulate the amplitude-dissipation and phase-dispersion characteristics. The truncated Taylor-series expansion (TE) algorithm is developed to approximate the mixed-domain operators. After that, the generalized pseudospectral approach can be directly used to solve the new wave equation. In addition, an accurate viscoelastic wave equation constructed by the fractional time derivatives is used to calculate reference solutions to evaluate the accuracy of the new expression. Modelling results indicate that the newly proposed viscoelastic wave equation using the new fractional Laplacians is more accurate than the conventional one, especially in a small Q medium (i.e. QP = QS = 5). Furthermore, we also examine the accuracy of the TE approximation with a series of Q values. A homogeneous model and the modified BP2004 viscoelastic model are used to investigate the accuracy of viscoelastic wave propagations using the TE algorithm. All modelling results fully demonstrate the performance of the newly proposed viscoelastic wave equation and numerical algorithm.
Optical emission-line luminosity function models for populations of supernova remnants
Authors: Kopsacheili M , Zezas A , Leonidaki I
Published: May 2022

We present a basic model for the calculation of the luminosity distribution of supernova remnant populations. We construct theoretical H$\rm \alpha \,$and joint [S ii]-H$\rm \alpha \,$luminosity functions for supernova remnants by combining prescriptions from a basic evolution model that provides the shock velocity and radius for SNRs of different age and pre-shock density, with shock excitation models that give the gas emissivity for shocks of different physical parameters. We assume a flat age distribution, and we explore the effect of different pre-shock density distributions or different magnetic parameters. We find a very good agreement between the shape of the model H$\rm \alpha \,$and the joint [S ii]-H$\rm \alpha \,$luminosity functions and those measured from SNR surveys in nearby galaxies.
Accretion on to a binary from a polar circumbinary disc
Authors: Smallwood Jeremy L , Lubow Stephen H , Martin Rebecca G
Published: May 2022

We present hydrodynamical simulations to model the accretion flow from a polar circumbinary disc on to a high eccentricity (e = 0.78) binary star system with near unity mass ratio (q = 0.83), as a model for binary HD 98800 BaBb. We compare the polar circumbinary disc accretion flow with the previously studied coplanar case. In the coplanar case, the circumbinary disc becomes eccentric and the accretion alternates from being dominant on to one binary member to the other. For the polar disc case involving a highly eccentric binary, we find that the circumbinary disc retains its initially low eccentricity and that the primary star accretion rate is always about the same as the secondary star accretion rate. Recent observations of the binary HD 98800 BaBb, which has a polar circumbinary disc, have been used to determine the value of the $\rm H\,\alpha$ flux from the brighter component. From this value, we infer that the accretion rate is much lower than for typical T Tauri stars. The eccentric orbit of the outer companion HD 98800 A increases the accretion rate on to HD 98800 B by ∼20 per cent after each periastron passage. Our hydrodynamical simulations are unable to explain such a low accretion rate unless the disc viscosity parameter is very small, α < 10−5. Additional observations of this system would be useful to check on this low accretion rate.
Impact of thermal Sunyaev–Zeldovich effect on cross-correlations between Planck cosmic microwave background lensing and SDSS galaxy density fields
Authors: Chen Tianyue , Remazeilles Mathieu
Published: May 2022

Residual foreground contamination by thermal Sunyaev–Zeldovich (tSZ) effect from galaxy clusters in cosmic microwave background (CMB) maps propagates into the reconstructed CMB lensing field, and thus biases the intrinsic cross-correlation between CMB lensing and large-scale structure (LSS). Through stacking analysis, we show that residual tSZ contamination causes an increment of lensing convergence in the central part of the clusters and a decrement of lensing convergence in the cluster outskirts. We quantify the impact of residual tSZ contamination on cross-correlations between the Planck 2018 CMB lensing convergence maps and the Sloan Digital Sky Survey-IV galaxy density data through cross-power spectrum computation. In contrast with the Planck 2018 tSZ-deprojected smica lensing map, our analysis using the tSZ-contaminated smica lensing map measures an $\sim\!2.5{{\ \rm per\,cent}}$ negative bias at multipoles ℓ ≲ 500 and transits to an $\sim\!9{{\ \rm per\,cent}}$ positive bias at ℓ ≳ 1500, which validates earlier theoretical predictions of the overall shape of such tSZ-induced spurious cross-correlation. The tSZ-induced lensing convergence field in Planck CMB data is detected with more than 1σ significance at ℓ ≲ 500 and more than 14σ significance at ℓ ≳ 1500, yielding an overall 14.8σ detection. We also show that masking galaxy clusters in CMB data is not sufficient to eliminate the spurious lensing signal, still detecting a non-negligible bias with 5.5σ significance on cross-correlations with galaxy density fields. Our results emphasize how essential it is to deproject the tSZ effect from CMB maps at the component separation stage and adopt tSZ-free CMB lensing maps for cross-correlations with LSS data.
Uromodulin and its association with urinary metabolites: the German Chronic Kidney Disease Study
Authors: Bächle Helena , Sekula Peggy , Schlosser Pascal , Steinbrenner Inga , Cheng Yurong , Kotsis Fruzsina , Meiselbach Heike , Stockmann Helena , Schönherr Sebastian , Eckardt Kai-Uwe , Devuyst Olivier , Scherberich Jürgen , Köttgen Anna , Schultheiss Ulla T ,   GCKD investigators, Eckardt Kai-Uwe , Meiselbach Heike , Schneider Markus P , Schiffer Mario , Prokosch Hans-Ulrich , Bärthlein Barbara , Beck Andreas , Reis André , Ekici Arif B , Becker Susanne , Becker-Grosspitsch Dinah , Alberth-Schmidt Ulrike , Hausknecht Birgit , Weigel Anke , Walz Gerd , Köttgen Anna , Schultheiß Ulla T , Kotsis Fruzsina , Meder Simone , Mitsch Erna , Reinhard Ursula , Floege Jürgen , Saritas Turgay , Schaeffner Elke , Baid-Agrawal Seema , Theisen Kerstin , Haller Hermann , Menne Jan , Zeier Martin , Sommerer Claudia , Theilinger Johanna , Wolf Gunter , Busch Martin , Paul Rainer , Sitter Thomas , Wanner Christoph , Krane Vera , Börner-Klein Antje , Bauer Britta , Kronenberg Florian , Raschenberger Julia , Kollerits Barbara , Forer Lukas , Schönherr Sebastian , Weissensteiner Hansi , Oefner Peter , Gronwald Wolfram , Schmid Matthias , Nadal Jennifer
Published: May 2022

Background

The progression of chronic kidney disease (CKD), a global public health burden, is accompanied by a declining number of functional nephrons. Estimation of remaining nephron mass may improve assessment of CKD progression. Uromodulin has been suggested as a marker of tubular mass. We aimed to identify metabolites associated with uromodulin concentrations in urine and serum to characterize pathophysiologic alterations of metabolic pathways to generate new hypotheses regarding CKD pathophysiology.

Methods

We measured urinary and serum uromodulin levels (uUMOD, sUMOD) and 607 urinary metabolites and performed cross-sectional analyses within the German Chronic Kidney Disease study (N = 4628), a prospective observational study. Urinary metabolites significantly associated with uUMOD and sUMOD were used to build weighted metabolite scores for urine (uMS) and serum uromodulin (sMS) and evaluated for time to adverse kidney events over 6.5 years.

Results

Metabolites cross-sectionally associated with uromodulin included amino acids of the tryptophan metabolism, lipids and nucleotides. Higher levels of the sMS [hazard ratio (HR) = 0.73 (95% confidence interval 0.64; 0.82), P = 7.45e-07] and sUMOD [HR = 0.74 (95% confidence interval 0.63; 0.87), P = 2.32e-04] were associated with a lower risk of adverse kidney events over time, whereas uUMOD and uMS showed the same direction of association but were not significant.

Conclusions

We identified urinary metabolites associated with urinary and serum uromodulin. The sUMOD and the sMS were associated with lower risk of adverse kidney events among CKD patients. Higher levels of sUMOD and sMS may reflect a higher number of functional nephrons and therefore a reduced risk of adverse kidney outcomes.
Progress in the development of a fully implantable brain–computer interface: the potential of sensing-enabled neurostimulators
Authors: Chen Yue , Zhang Guokun , Guan Linxiao , Gong Chen , Ma Bozhi , Hao Hongwei , Li Luming
Published: May 2022

This perspective article investigates the performance of using a sensing-enabled neurostimulator as a motor brain-computer interface.
The Role of Structural Tones in Establishing Mode in Renaissance Counterpoint
Authors: Arthur Claire , Cumming Julie E. , Schubert Peter
Published: May 2022

The authors present a corpus analysis of a set of forty-four Renaissance contrapuntal duos with the aim of testing the theoretical assumption that melodic leaps, outlines, and perfect vertical intervals will be used in a way that highlights the principal interval species of a mode. Using counts of “structural tones” or “structural intervals” in isolation, the authors evaluated their potential to predict the mode of a piece using statistical modeling as well as behavioral experiments with early music experts. The authors found that both pitch-class distribution and perfect vertical intervals can be used to provide a decent estimate of mode family in Renaissance duos and that distinguishing between authentic and plagal modes with the same final is very difficult to do, even when experts consider the whole score.