bluuebunny/crossref_metadata_2025 huggingface dataset:
Simulation of the magnetic system of a linear motor for a delimber
Authors: Antonov Sergey , Nikitenko Gennady , Adoshev Andrey , Devederkin Igor , Efanov Alexey
Published: October 2021

The existing pruning shears and delimbers have many drawbacks that limit their widespread use in the production process. These are such disadvantages as large weight and dimensions, high power consumption, vibration and noise, low mobility due to being tied to an energy source. DC motors are used to drive the cutting blades. Their main disadvantage is the low operational reliability of such an element as electric brushes. The use of the kinematic transformation of the rotational motion of the electric motor into the reciprocating motion of the blades reduces the overall efficiency of the device and increases the consumption of electrical energy. The proposed linear electric motor for the delimber drive will increase the efficiency, operational reliability and reduce energy consumption for cutting tree branches. A feature of a linear electric motor is the use of two magnetizing coils, which are switched on alternately. The use of a thin element in the magnetic system makes it possible to redistribute the obtained magnetic flux towards the armature of the linear electric motor. The armature of the electric motor consists of magnetic and nonmagnetic bushings of a certain design. This allows you to obtain a magnetic flux, which, passing along the armature, creates an electromagnetic force that sets it in motion. The cutting blade is then anchored. This allows you to improve the characteristics of the proposed delimber. The main challenge in the design of the delimber is to create the maximum force on the cutting blade required to cut branches. For this, it is necessary to perform an improvement of the magnetic system of the linear electric motor. For this purpose, the simulation of the magnetic system was carried out in the ElCut program.
Resource-saving environmentally friendly technologies and waste processing as a key to improve the sugar beet production efficiency
Authors: Saltyk Ivan , Bolokhontseva Yulia
Published: October 2021

The world experience shows that in the 21st century, the sustainable development of the Russian beet production and sugar industry is impossible without scientific achievements. It requires low-cost resource-saving technologies that can save resources and increase the efficiency of sugar beet production. It was found that in order to increase the profitability of the sugar beet production industry, the following technologies should be used: intensive (application of herbicides); resource-saving (strip post-emergence application of herbicides); environmental protection (production of beets without herbicides, but with the use of manual labor). The intensification of sugar beet processing entails the use of new technologies that can reduce the volume of waste. The waste-free production makes it possible to strengthen the role of secondary resources as raw materials in the manufacture of various products. Secondary raw materials are used as raw materials. Structural and investment policies pursued by the government do not stimulate their processing. Therefore, beet-sugar agro-associations themselves should solve these issues. Their efforts should be aimed at ensuring the comprehensive processing of sugar beets to produce high-quality valuable food and feed products from production waste.
Umgang mit der Dauermedikation bei Patienten mit Diabetes mellitus
Authors: Rupprecht Bernd , Stöckl Alexander
Published: October 2021

Für die perioperative Phase besteht bei Patienten mit Diabetes mellitus ein erhöhtes Risiko für Komplikationen, z. B. durch Entgleisung des Glukosestoffwechsels, erhöhte Rate kardiovaskulärer Ereignisse, Verschlechterung einer vorbestehenden Niereninsuffizienz und vermehrt auftretende Wundinfektionen. Zudem können Nebenwirkungen der antidiabetischen Therapie auftreten. Ein spezieller Umgang mit der Dauermedikation bei solchen Patienten ist wichtig.
Synthesis of Novel Chiral Phenanthroline Ligands and a Copper Complex
Authors: Yang Xueyan , Zhang Zhipeng , Tang Jingjing , Li Jian
Published: October 2021

A novel class of chiral multidentate ligands has been designed and synthesized from the important classic ligand 1,10-phenanthroline and amino acids. The ligands were proven to be able to coordinate with copper(2+) ion by the formation of a novel chiral copper complex, the structure of which was determined by single-crystal X-ray diffraction.
Iron-Catalyzed Synthesis of Pyridines from α,β-Unsaturated Ketoxime Acetates and N-Acetyl Enamides
Authors: Duan Jindian , Xu Gaochen , Yan Huan , Zhang Sai , Wu Qinghuan , Guo Kai
Published: October 2021

A new method of FeCl2-catalyzed [4+2] annulation of α,β-unsaturated ketoxime acetates with N-acetyl enamides in batch and flow is reported. The current strategy features low-cost catalytic system, use of electron-rich olefins, operational simplicity, and broad substrate scope, thus providing a facile and efficient access to substituted pyridines in moderate to good yields.
The Preparation and Application of Diaryliodonium Salts Derived from Gemfibrozil and Gemfibrozil Methyl Ester
Authors: Wu Panpan , Chen Chao , Zhou Jun , Bao Zhiyuan
Published: October 2021

The diaryliodonium salts derived from gemfibrozil and gemfibrozil methyl ester were synthesized from ArI(OH)OTs or bis(4-methoxyphenyl)iodonium diacetate with good regioselectivity. These iodonium salts were successfully used in the derivatization of gemfibrozil or gemfibrozil methyl ester, including fluorination, alkynylation, aryl­ation, etherification, esterification, and iodination reactions.
Triflic Anhydride (Tf2O)-Activated Transformations of Amides, Sulfoxides and Phosphorus Oxides via Nucleophilic Trapping
Authors: Kang Jun Yong , Huang Hai
Published: October 2021

Trifluoromethanesulfonic anhydride (Tf2O) is utilized as a strong electrophilic activator in a wide range of applications in synthetic organic chemistry, leading to the transient generation of a triflate intermediate. This versatile triflate intermediate undergoes nucleophilic trapping with diverse nucleophiles to yield novel compounds. In this review, we describe the features and applications of triflic anhydride in organic synthesis reported in the past decade, especially in amide, sulfoxide, and phosphorus oxide chemistry through electrophilic activation. A plausible mechanistic pathway for each important reaction is also discussed.

1 Introduction

2 Amide Chemistry

2.1 Carbon Nucleophiles

2.2 Hydrogen Nucleophiles

2.3 Nitrogen Nucleophiles

2.4 Oxygen and Sulfur Nucleophiles

2.5 hosphorus Nucleophiles

2.6 A Vilsmeier-Type Reagent

2.7 Umpolung Reactivity in Amides

3 Sulfoxide Chemistry

3.1 Oxygen Nucleophiles

3.2 Carbon Nucleophiles

3.3 Nitrogen Nucleophiles

3.4 Thionium Reagents

4 Phosphorus Chemistry

4.1 Hendrickson’s Reagent

4.2 Diaryl Phosphine Oxides

4.3 Phosphonates, Phosphates and Phosphinates

5 Conclusion and Outlook
Motion Analytics of Trapezius Muscle Activity in an 18-Year-Old Female with Extended Upper Brachial Plexus Birth Palsy
Authors: Lin Jasmine J. , Chan Gromit Y.Y. , Silva Cláudio T. , Nonato Luis G. , Raghavan Preeti , McGrath Aleksandra , Chu Alice
Published: October 2021

Background The trapezius muscle is often utilized as a muscle or nerve donor for repairing shoulder function in those with brachial plexus birth palsy (BPBP). To evaluate the native role of the trapezius in the affected limb, we demonstrate use of the Motion Browser, a novel visual analytics system to assess an adolescent with BPBP.

Method An 18-year-old female with extended upper trunk (C5–6–7) BPBP underwent bilateral upper extremity three-dimensional motion analysis with Motion Browser. Surface electromyography (EMG) from eight muscles in each limb which was recorded during six upper extremity movements, distinguishing between upper trapezius (UT) and lower trapezius (LT). The Motion Browser calculated active range of motion (AROM), compiled the EMG data into measures of muscle activity, and displayed the results in charts.

Results All movements, excluding shoulder abduction, had similar AROM in affected and unaffected limbs. In the unaffected limb, LT was more active in proximal movements of shoulder abduction, and shoulder external and internal rotations. In the affected limb, LT was more active in distal movements of forearm pronation and supination; UT was more active in shoulder abduction.

Conclusion In this female with BPBP, Motion Browser demonstrated that the native LT in the affected limb contributed to distal movements. Her results suggest that sacrificing her trapezius as a muscle or nerve donor may affect her distal functionality. Clinicians should exercise caution when considering nerve transfers in children with BPBP and consider individualized assessment of functionality before pursuing surgery.
Elbow Instability
Authors: Graf Dimitri N. , Fritz Benjamin , Bouaicha Samy , Sutter Reto
Published: October 2021

The stability of the elbow is based on a combination of primary (static) and secondary stabilizers (dynamic). In varus stress, the bony structures and the lateral ulnar collateral ligament (LUCL) are the primary stabilizers, and in valgus stress, the ulnar collateral ligament (UCL) is the primary stabilizer. The flexor and extensor tendons crossing the elbow joint act as secondary stabilizers. Elbow instability is commonly divided into acute traumatic and chronic instability. Instability of the elbow is a continuum, with complete dislocation as its most severe form.

Posterolateral rotatory instability is the most common elbow instability and can be detected at imaging both in the acute as well as the chronic phase. Imaging of suspected elbow instability starts with radiographs. Depending on the type of injury suspected, it is followed by magnetic resonance imaging (MRI) or computed tomography evaluation for depiction of a range of soft tissue and osseous injures. The most common soft tissue injuries are tears of the LUCL and the radial collateral ligament; the most common osseous injuries are an osseous LUCL avulsion, a fracture of the coronoid process, and a radial head fracture.

Valgus instability is the second most common instability and mostly detected in the chronic phase, with valgus extension overload the dominant pattern of injury. The anterior part of the UCL is insufficient in valgus extension overload due to repetitive medial tension seen in many overhead throwing sports, with UCL damage readily seen at MRI.
Challenges, Barriers, and Good Practices in the Implementation of Rashtriya Bal Swasthya Karyakram in Jodhpur, India
Authors: Kumar Niraj , Joshi Nitin Kumar , Jain Yogesh Kumar , Singh Kuldeep , Bhardwaj Pankaj , Suthar Praveen , Manda Balwant , Kirti Ravi
Published: October 2021

Introduction

The Rashtriya Bal Swasthya Karyakram of the Government of India subsumes the existing school health program to provide care and treatment to children below 18 years through screening and early interventions. Benefitting an estimated 270 million children for 30 preidentified conditions is a step toward “health for all.” Although the program is running since 2013, due to paucity of studies particularly in Thar desert region and its associated challenges, this study was planned to assess challenges and good practices in the implementation of RBSK in Jodhpur.

Objectives

To assess the challenges, barriers, and good practices in the implementation of RBSK among the mobile health team (MHT) in Jodhpur, Rajasthan.

Methods

A community based descriptive cross-sectional study in all 11 medical blocks of Jodhpur district, with purposive sampling to invite all members of MHT to participate in the study as grassroot workers was planned. A pretested, semistructured questionnaire was processed using SPSS for quantitative component and in-depth interviews were reported using qualifiers for qualitative observations.

Results

As much as 74.1% (n = 40) of the staff perceived the trainings to be sufficient for daily work needs but needed more sessions for birth defects (33.3%) and development delays (29.6%). As much as 96.3% (n = 52) of the staff considered salaries to be low and 55.5% were dissatisfied with the jobs. However, 70.4% found targets to be achievable and 76% found the work environment helpful. Taboos and superstitions in community, harsh climate, dual workload on pharmacists as data operators, and noninclusion of AYUSH medicines for AYUSH medical officers (MOs) were few of the challenges, while good practices such as fully equipped MHTs, readily available vehicles, information education communication (IEC) materials, and treatment coverage under Bhamashah Bima Yojana (BSBY) were also observed.

Conclusion

Many good practices were observed during the study which can be adopted by other states for better implementations elsewhere. Certain challenges such as belief in quackery, superstitions and taboos could be minimized by conducting rapport-building meetings with community stakeholders. Feedback and regular trainings of MHT staff can further increase the success manifold.
Editorial
Authors: Lang Michael
Published: October 2021

Die Krankenhäuser stehen auch 2021 vor vielen Herausforderungen. Zu den Einschränkungen durch die Covid-19-Pandemie kommt die nach wie vor schwierige finanzielle Situation vieler kleinerer und mittelgroßer Häuser. Diese sollten jetzt die strategischen Weichenstellungen vornehmen, damit sie auch nach der Pandemie noch eine wirtschaftliche Perspektive haben. 2021 steht aber auch im Zentrum des Krankenhauszukunftsgesetzes (KHZG), das Schwung in die Digitalisierung bringen soll. Die Kommunikation mit Patienten über vielfältige digitale Kanäle wird für Kliniken zunehmend zu einem wichtigen Marketinginstrument. Ein Dauerbrenner in den Krankenhäusern ist der Personalmangel. Kliniken benötigen eine gute Strategie, um medizinische Führungskräfte zu gewinnen und zu halten.
Ultrafast valley polarization in bilayer graphene
Authors: Kumar Pardeep , Herath Thakshila M. , Apalkov Vadym
Published: October 2021

We study theoretically the interaction of a bilayer graphene with a circularly polarized ultrafast optical pulse of a single oscillation at an oblique incidence. The normal component of the pulse breaks the inversion symmetry of the system and opens up a dynamical bandgap due to which a valley-selective population of the conduction band becomes sensitive to the angle of incident of the pulse. We show that the magnitude of the valley polarization can be controlled by the angle of incidence, the amplitude, and the angle of in-plane polarization of the chiral optical pulse. Subsequently, a sequence of a circularly polarized pulse followed by a linearly polarized femtosecond-long pulse can be used to control and probe the valley polarization created by the preceding pulse. Our protocol provides a favorable platform to design ultrafast all-optical valleytronic information processing.
Interaction of tropical cyclone-like vortices with sea-surface temperature anomalies and topography in a simple shallow-water atmospheric model
Authors: Kurganov Alexander , Liu Yongle , Zeitlin Vladimir
Published: October 2021

In this paper, we show how the thermal effects affect trajectories, intensity, and formation of secondary structures during the passages of strong tropical cyclone-like vortices over oceanic warm and cold pools as well as over an island-type topography. Our results are obtained using the moist-convective thermal rotating shallow-water atmospheric model recently developed in [A. Kurganov et al., “Moist-convective thermal rotating shallow-water model,” Phys. Fluids 32, 066601 (2020)]. This model introduces thermodynamics of the moist air and moist convection in the standard rotating shallow-water models and allows to include in the latter atmosphere–ocean interactions in an elementary way.
Systematic studies of the effects of group-III dopants (La, Y, Al, and Gd) in Hf0.5Zr0.5O2 ferroelectrics by ab initio simulations
Authors: Zhao Liang , Liu Jirong , Zhao Yi
Published: October 2021

La-doped Hf0.5Zr0.5O2 (HZO) ferroelectrics have demonstrated great potential to solve the endurance challenge of hafnia-based ferroelectric memory. In this work, we systematically studied the doping effects of La in HZO by ab initio simulations and theoretically compared it with three other commonly used group-III dopants (Al, Y, and Gd). The physical mechanisms behind superior endurance are thoroughly analyzed based on the calculation results regarding phase stability, oxygen vacancy formation energy, migration barrier, and electronic structures. It has been discovered that among the four dopant candidates, La has the strongest stabilization effect of the ferroelectric phase in HZO. Also, under stoichiometric doping conditions, La and other group-III dopants were observed to increase the oxygen vacancy formation energy and make HZO less susceptible to dielectric breakdown. Finally, La, Al, or Y dopants replacing Hf or Zr can getter migrating oxygen vacancies and passivate the associated defect states in the bandgap. Based on these observations, guidelines were proposed for designing the doping method and concentrations to achieve the best endurance.
Engineering local strain for single-atom nuclear acoustic resonance in silicon
Authors: O'Neill Laura A. , Joecker Benjamin , Baczewski Andrew D. , Morello Andrea
Published: October 2021

Mechanical strain plays a key role in the physics and operation of nanoscale semiconductor systems, including quantum dots and single-dopant devices. Here, we describe the design of a nanoelectronic device, where a single nuclear spin is coherently controlled via nuclear acoustic resonance (NAR) through the local application of dynamical strain. The strain drives spin transitions by modulating the nuclear quadrupole interaction. We adopt an AlN piezoelectric actuator compatible with standard silicon metal–oxide–semiconductor processing and optimize the device layout to maximize the NAR drive. We predict NAR Rabi frequencies of order 200 Hz for a single 123Sb nucleus in a wide region of the device. Spin transitions driven directly by electric fields are suppressed in the center of the device, allowing the observation of pure NAR. Using electric field gradient-elastic tensors calculated by the density-functional theory, we extend our predictions to other high-spin group-V donors in silicon and to the isoelectronic 73Ge atom.
Perspective on photovoltaic optical power converters
Authors: Fafard Simon , Masson Denis P.
Published: October 2021

Optical wireless power transmission (OWPT) can be used for applications that cannot access traditional power using metal wires. Photovoltaic power-converting III-V semiconductor devices are the core components required for achieving such remote and galvanically isolated power deployments. The development of high-efficiency power converters has already propelled several sensors and probe applications. This growing applied physics field is leveraging the use of ubiquitous laser diode products, now commonly available at various wavelengths. Novel multijunction designs, based on the vertical epitaxial heterostructure architecture devices, have recently allowed fiber-based and free-space applications to quickly progress to higher electrical powers and to benefit from other laser wavelengths. Here, we discuss the perspectives of such multijunction power converters from the viewpoint of realizing additional OWPT deployments and for enabling more probe, sensor, or electronic subsystem power capabilities. The Perspective hence provides a roadmap for devices achieving not only higher conversion efficiency, but also elaborates on the practical aspects necessary to concurrently push the power converters to higher output powers. The photovoltaic multijunction power-converting device is particularly a game-changer for smartly increasing the output voltage and therefore maintaining practical optimal external loads at high laser input powers. Examples of conversion efficiencies above 60% for output powers up to 17.5 W are demonstrated at ∼808 nm in this study, and up to 22 W of output power is obtained with an efficiency of 48.9% at ∼980 nm.
Berry curvature generation detected by Nernst responses in ferroelectric Weyl semimetal
Authors: Zhang Cheng-Long , Liang Tian , Bahramy M. S. , Ogawa Naoki , Kocsis Vilmos , Ueda Kentaro , Kaneko Yoshio , Kriener Markus , Tokura Yoshinori
Published: October 2021

Significance

An ideal Weyl semimetal with high tunability is an undoubtedly important platform for realizing and manipulating exotic quantum properties of topological semimetals. Currently, all the existing nonmagnetic Weyl semimetals are not ideal and out of external control, namely, no couplings to an order parameter. In this work, we report with a topological phase transition diagram the successful realization of a Weyl semimetal phase by chemically engineering the PbTe-SnTe alloy. Furthermore, we demonstrate that the Weyl semimetal phase is strongly coupled with the underlying ferroelectric order, which exhibits turn on/off properties when the ferroelectric order appears/disappears. The Weyl phase is detected experimentally by a Berry curvature–sensitive thermoelectric probe called in-plane Nernst effect, which excludes the Drude response.
iASPP contributes to cell cortex rigidity, mitotic cell rounding, and spindle positioning
Authors: Mangon Aurélie , Salaün Danièle , Bouali Mohamed Lala , Kuzmić Mira , Quitard Sabine , Thuault Sylvie , Isnardon Daniel , Audebert Stéphane , Puech Pierre-Henri , Verdier-Pinard Pascal , Badache Ali
Published: October 2021

iASPP is a protein mostly known as an inhibitor of p53 pro-apoptotic activity and a predicted regulatory subunit of the PP1 phosphatase, which is often overexpressed in tumors. We report that iASPP associates with the microtubule plus-end binding protein EB1, a central regulator of microtubule dynamics, via an SxIP motif. iASPP silencing or mutation of the SxIP motif led to defective microtubule capture at the cortex of mitotic cells, leading to abnormal positioning of the mitotic spindle. These effects were recapitulated by the knockdown of the membrane-to-cortex linker Myosin-Ic (Myo1c), which we identified as a novel partner of iASPP. Moreover, iASPP or Myo1c knockdown cells failed to round up upon mitosis because of defective cortical stiffness. We propose that by increasing cortical rigidity, iASPP helps cancer cells maintain a spherical geometry suitable for proper mitotic spindle positioning and chromosome partitioning.
Reconfigurable shape-morphing flexible surfaces realized by individually addressable photoactuator arrays
Authors: Niu Dong , Jiang Weitao , Li Dachao , Ye Guoyong , Luo Feng , Liu Hongzhong
Published: October 2021

Inspired by the impressive shape reconfigurability in natural systems, stimulus-responsive soft materials have been exploited to enable reconfigurable surface changes, relying on controllable deformations inner soft materials and spatiotemporally varying external stimuli. Among these, light stimulus, due to its high degree of spatial and temporal control manner, has been becoming a particularly powerful actuation means. Especially, photothermal shape transformations induced by bilayered structures, combining light absorption layer and an active layer of hydrogels, SMPs (Shape Memory Polymers), and nanocomposites, have provided a facile reconfigurable scheme. Here, we proposed reconfigurable shape-morphing flexible surfaces with individually addressable photoactuators arrays. By adjusting near-infrared radiation intensity and actuators thickness, the deformations of each actuator can be desirably tuned up to 350 μm. Additionally, actuator arrays can be individually photoactuated one by one due to the remote and straightforward control manner, which give rise to distinct surface morphology. Furthermore, multiple actuators are enabled to demonstrate coupled photomechanical actuation, causing broader area surface reconfigurations. Finally, we tried to explore shape-morphing flexible surfaces applications in a deformable mirror prototype with 19 actuator arrays. Based on photomechanical deformation simulation from COMSOL MultiPhysics, surface change capability was preliminarily researched. We envision that our proposed photoactuated deformable mirror will have a significant impact on the novel design in the future deformable mirrors and metasurfaces.
Phase-field modeling of faceted growth in solidification of alloys
Authors: Xing Hui , An Qi , Dong Xianglei , Han Yongsheng
Published: October 2021

A regularization of the surface tension anisotropic function used in vapor-liquid-solid nanowire growth was introduced into the quantitative phase-field model to simulate the faceted growth in solidification of alloys. Predicted results show that the value of δ can only affect the region near the tip, and the convergence with respect to δ can be achieved with the decrease of δ near the tip. It can be found that the steady growth velocity is not a monotonic function of the cusp amplitude, and the maximum value is approximately at ε = 0.8 when the supersaturation is fixed. Moreover, the growth velocity is an increasing function of supersaturation with the morphological transition from facet to dendrite.
A high rectification efficiency Si0.14Ge0.72Sn0.14-Ge0.82Sn0.18-Ge quantum structure n-MOSFET for 2.45 GHz weak energy microwave wireless energy transmission
Authors: Zhang Dong , Song Jianjun , Xue Xiaohuan , Zhang Shiqi
Published: October 2021

The design strategy and efficiency optimization of a Ge-based n-type metal–oxide–semiconductor field-effect transistor (n-MOSFET) with a Si0.14Ge0.72Sn0.14–Ge0.82Sn0.18–Ge quantum structure used for 2.45 GHz weak energy microwave wireless energy transmission is reported. The quantum structure combined with δ-doping technology is used to reduce the scattering of the device and improve its electron mobility; at the same time, the generation of surface channels is suppressed by the Si0.14Ge0.72Sn0.14 cap layer. By adjusting the threshold voltage of the device to 91 mV, setting the device aspect ratio to 1 μm/0.4 μm and adopting a novel diode connection method, the rectification efficiency of the device is improved. With simulation by Silvaco TCAD software, good performance is displayed in the transfer and output characteristics. For a simple half-wave rectifier circuit with a load of 1 pf and 20 kΩ, the rectification efficiency of the device can reach 7.14% at an input power of –10 dBm, which is 4.2 times that of a Si MOSFET (with a threshold voltage of 80 mV) under the same conditions; this device shows a better rectification effect than a Si MOSFET in the range of –30 dBm to 6.9 dBm.
Mass splitting of vector mesons and spontaneous spin polarization under rotation *
Authors: Wei Minghua , Jiang Yin , Huang Mei
Published: October 2021

In this study, we investigate the effect of rotation on the masses of scalar and vector mesons in the framework of the 2-flavor Nambu-Jona-Lasinio model. The existence of rotation produces a tedious quark propagator and a corresponding polarization function. By applying the random phase approximation, the meson mass is numerically calculated. It is found that the behavior of scalar and pseudoscalar meson masses under angular velocity ω is similar to that at a finite chemical potential; both rely on the behavior of the constituent quark mass and reflect the property related to chiral symmetry. However, vector meson ρ masses have a more profound relation to rotation. After analytical and numerical calculations, it turns out that at low temperature and small chemical potential, the mass for spin component

of a vector meson under rotation exhibits a very simple mass splitting relation

, similar to the Zeeman splitting of a charged meson under magnetic fields. Furthermore, the mass of the spin component

of vector meson ρ decreases linearly with ω and reaches zero at

, which indicates that the system will develop

vector meson condensation and the system will be spontaneously spin-polarized under rotation.
Cause Analysis and Control Measures for Roadway Bursting Caused by Mining-induced Tremors of Hard Roof–A Case Study of the Inner Mongolia Coalfield, China
Authors: Liu Zhigang , Zhang Ruoxiang , Sun Xikui , Shang Wenzheng
Published: October 2021

Rock burst caused by mining-induced tremors is a dynamic disaster in mines that can cause great damage. Based on the mining-induced tremor that occurred at the MKQ Coal

Mine, Inner Mongolia Autonomous Region, China, on March 3, 2018, the present paper studies the mechanism of mining-induced tremor occurrence using theoretical analysis, numerical simulation, and focal mechanism. The study found four inferior strata and a primary key stratum in the overlying strata on LW3102, and discovered that upon breaking the key stratum movement releases a large amount of energy thereby causing the mining-induced tremor. When the internal stress of the coal pillar in the air-return way of LW3102 reaches 72.77 MPa, the static load stress concentration appears in the coal body near the air-return way, thereby facilitating easy coal body instability due to the overlay of the dynamic load, which in turn produces the rock burst. Based on the analysis of the moment tensor theory, this study finds the ratio of the moment tensor double couple part (MDC) of the strong mining-induced tremor focal to be 8.91%, indicating that the tensile fracture appears in overlying strata on LW3102, and a large amount of energy is released, thereby inducing the mining-induced tremor. The rock burst of the working face is controlled by applying control measures.
ℓ-torsion bounds for the class group of number fields with an ℓ-group as Galois group
Authors: Klüners Jürgen , Wang Jiuya
Published: October 2021

We describe the relations among the

ℓ
\ell

-torsion conjecture, a conjecture of Malle giving an upper bound for the number of extensions, and the discriminant multiplicity conjecture. We prove that the latter two conjectures are equivalent in some sense. Altogether, the three conjectures are equivalent for the class of solvable groups. We then prove the

ℓ
\ell

-torsion conjecture for

ℓ
\ell

-groups and the other two conjectures for nilpotent groups.
Microtubule dynamics influence the retrograde biased motility of kinesin-4 motor teams in neuronal dendrites
Authors: Masucci Erin M. , Relich Peter K. , Lakadamyali Melike , Ostap E. Michael , Holzbaur Erika L. F.
Published: October 2021

With reconstituted in vitro systems and live cell experiments using optogenetic motor recruitment, we asked how KIF21B motors move with a retrograde bias on mixed polarity microtubule networks. Plus end–out MTs were more dynamic than plus end–in MTs in dendrites. These native MT dynamics contribute to the retrograde bias of cargo movement.
American Intellectual History: A Very Short Introduction
Authors: Ratner-Rosenhagen Jennifer
Published: October 2021

American Intellectual History: A Very Short Introduction provides an introduction to the history of American thought from the sixteenth century up until the present. Long before the United States was a nation, it was a set of ideas, projected onto the New World by European commentators and explorers. American thought grew from this foundation of expectation and experience, both enriched and challenged over the centuries by developments including the Revolutionary War, westward expansion, the rise of capitalism, the proliferation of diverse religions, immigration, industrialization, and the emergence of the United States as a superpower. This introduction provides an overview of some of the most compelling episodes and abiding preoccupations in American thought, while showing how ideas have been major forces driving the course of American history.
From republican to Romantic
Authors: Ratner-Rosenhagen Jennifer
Published: October 2021

‘From republican to Romantic’ discusses how Enlightenment ideas came under pressure from the dramatic changes in American life during the early republic. Rapid population growth, westward expansion, urbanization, and industrialization tested the limits of Enlightenment thought, while new Romantic sensibilities shaped Americans’ response to their changing political and social realities. A shared concern during this period was the perceived absence of a truly “American” democratic culture, and this fostered efforts to build a variety of new intellectual institutions. The transcendentalists played a central role in trying to create a unifying intellectual culture befitting a new democracy, while the mental and moral worlds of Northerners and Southerners pulled farther apart over the issue of slavery.
Contests of intellectual authority
Authors: Ratner-Rosenhagen Jennifer
Published: October 2021

‘Contests of intellectual authority’ examines the clash of ideas and ideologies that shaped America in the years leading up to the Civil War through the end of the nineteenth century. It opens with two historical events of 1859 that altered the course of American thought: John Brown’s raid on Harpers Ferry and the publication of Charles Darwin’s On the Origin of Species. The moral challenges raised by race-based slavery and evolutionary theory shaped American notions of freedom, divine providence, and human responsibility. While the Civil War ultimately resolved a political and legal dispute, it did not resolve larger intellectual, religious, and moral ones. These contests of moral authority and the range of human responses to human problems are on full display in late nineteenth-century American life.
The opening of the American mind
Authors: Ratner-Rosenhagen Jennifer
Published: October 2021

‘The opening of the American mind’ challenges the perception of postwar American intellectual life as a period of staid traditionalism, stifling uniformity, complacency, and consensus. While some aspects of the 1950s and early 1960s Cold War culture were intellectually suffocating, others helped to widen Americans’ intellectual horizons. America’s new status as a global superpower stimulated the development of its intellectual and cultural institutions at a pace unprecedented in its history. The dramatic expansion of higher education, think tanks, and the print culture marketplace contributed to the opening of mid-century American thought. Varieties of existentialism, the creation of a lively conservative tradition, and the growing American interest in intellectual movements and spiritual practices from around the world helped Americans “breathe a larger air.”
Time until Newton
Authors: Ismael Jenann
Published: October 2021

‘Time until Newton’ begins by describing the historical origin of calendars and mathematical ways of representing time. It discusses the Aristotelian worldview, which formed the dominant understanding of the Universe in the West from the time of Aristotle until the 17th century when Newton proposed his theory of motion. This was the first physical theory in the mathematical form that we expect nowadays and by making space and time subjects of scientific investigation Newton forever changed the way that people studied space and time. After the publication of his theory, a debate about whether space and time were entities or systems of relations broke out between Newton and the philosopher Gottfried Wilhelm Leibniz. A series of letters between Leibniz and the philosopher Samuel Clarke focusing on this question introduced the mathematical tools of symmetry and invariance that would become important in subsequent study of the structure of space and time.
The arrow of time
Authors: Ismael Jenann
Published: October 2021

‘The arrow of time’ discusses where the arrow of time comes from. The fundamental laws of motion do not distinguish past and future. And yet the everyday world is full of manifestly asymmetric processes. This chapter discusses the apparent mismatch between the fundamental laws of nature and the manifest asymmetry of the everyday world. The temporal asymmetry is made precise by the second law of thermodynamics and the tension between the second law and the fundamental laws is addressed by the development of statistical mechanics.
The time of human experience
Authors: Ismael Jenann
Published: October 2021

‘The time of human experience’ examines whether the sense that time flows or passes can be recovered from within a relativistic image of time. On first encountering the relativistic image of time, many people are puzzled that it looks like a static block of events. Many physicists, including Einstein, thought that relativity theory vindicated the Parmenidean view that the passage of time is an illusion
The Bible in the post-colonial world
Authors: Riches John
Published: October 2021

‘The Bible in the post-colonial world’ describes how colonizers and missionaries used the Bible. During the colonization of Latin America, the narratives of the conquest of Canaan in Joshua and Judges provided support not only for conquest, but also for the merciless killing of those who refused to submit. Nevertheless, Latin America also saw a powerful movement arise to rescue the Bible from its colonial misuse. In Africa too, the Bible could be used as an instrument both of oppression and of liberation. In South Africa, the stories of the Exodus and the entry to the Promised Land played a significant part in the emerging ideology of Afrikanerdom. At the same time, church leaders like Desmond Tutu used the language of the Bible to mount a powerful attack on apartheid.
The Bible in politics
Authors: Riches John
Published: October 2021

‘The Bible in politics’ examines the place of the Bible in politics. Martin Luther and the mainstream Reformers used it to justify the power of the sword and to draw a clear line between the laws which were to govern secular society and the teaching of the Sermon on the Mount, which was intended only for Christians. The Quakers in England, like the Anabaptists, interpreted the commandments of the Sermon of the Mount literally and so refused to bear arms or to swear oaths. It is worth considering how the Bible has been a major source of the patriarchy which has marked Christian societies and exploring some feminist critiques of biblical narratives.
A high-dimensional power analysis of the conditional randomization test and knockoffs
Authors: Wang Wenshuo , Janson Lucas
Published: October 2021

In many scientific applications, researchers aim to relate a response variable $Y$ to a set of potential explanatory variables $X = (X_1,\dots,X_p)$, and start by trying to identify variables that contribute to this relationship. In statistical terms, this goal can be understood as trying to identify those $X_j$ on which $Y$ is conditionally dependent. Sometimes it is of value to simultaneously test for each $j$, which is more commonly known as variable selection. The conditional randomization test, CRT, and model-X knockoffs are two recently proposed methods that respectively perform conditional independence testing and variable selection by computing, for each $X_j$, any test statistic on the data and assessing that test statistic’s significance, by comparing it with test statistics computed on synthetic variables generated using knowledge of the distribution of $X$. The main contribution of this article is the analysis of the power of these methods in a high-dimensional linear model, where the ratio of the dimension $p$ to the sample size $n$ converges to a positive constant. We give explicit expressions for the asymptotic power of the CRT, variable selection with CRT $p$-values, and model-X knockoffs, each with a test statistic based on the marginal covariance, the least squares coefficient or the lasso. One useful application of our analysis is direct theoretical comparison of the asymptotic powers of variable selection with CRT $p$-values and model-X knockoffs; in the instances with independent covariates that we consider, the CRT probably dominates knockoffs. We also analyse the power gain from using unlabelled data in the CRT when limited knowledge of the distribution of $X$ is available, as well as the power of the CRT when samples are collected retrospectively.
Universal Community Nucleic Acid Testing for Coronavirus Disease 2019 (COVID-19) in Hong Kong Reveals Insights Into Transmission Dynamics: A Cross-Sectional and Modeling Study
Authors: Yang Bingyi , Tsang Tim K , Gao Huizhi , Lau Eric H Y , Lin Yun , Ho Faith , Xiao Jingyi , Wong Jessica Y , Adam Dillon C , Liao Qiuyan , Wu Peng , Cowling Benjamin J , Leung Gabriel M
Published: October 2021

Background

Testing of an entire community has been used as an approach to control coronavirus disease 2019 (COVID-19). In Hong Kong, a universal community testing program (UCTP) was implemented at the fadeout phase of a community epidemic in July to September 2020. We described the utility of the UCTP in finding unrecognized infections and analyzed data from the UCTP and other sources to characterize transmission dynamics.

Methods

We described the characteristics of people participating in the UCTP and compared the clinical and epidemiological characteristics of COVID-19 cases detected by the UCTP versus those detected by clinical diagnosis and public health surveillance (CDPHS). We developed a Bayesian model to estimate the age-specific incidence of infection and the proportion of cases detected by CDPHS.

Results

In total, 1.77 million people, 24% of the Hong Kong population, participated in the UCTP from 1 to 14 September 2020. The UCTP identified 32 new infections (1.8 per 100000 samples tested), consisting of 29% of all local cases reported during the two-week UCTP period. Compared with the CDPHS, the UCTP detected a higher proportion of sporadic cases (62% vs 27%, P<.01) and identified 6 (out of 18) additional clusters during that period. We estimated that 27% (95% credible interval: 22%, 34%) of all infections were detected by the CDPHS in the third wave.

Conclusions

We reported empirical evidence of the utility of population-wide COVID-19 testing in detecting unrecognized infections and clusters. Around three quarters of infections have not been identified through existing surveillance approaches including contact tracing.
Financialisation, regional economic development and the coronavirus crisis: a time for spatial monetary policy?
Authors: Sokol Martin , Pataccini Leonardo
Published: October 2021

This paper argues that ‘spatial monetary policy’ may be needed to achieve more territorially balanced economic development. Central banks have been key in fostering financialised economies while also preventing their collapse in times of crisis—a role further strengthened by the coronavirus pandemic. Central banks have thus become the most powerful economic policy-making institutions, just when spatial disparities are likely to deepen. In the context of crisis-ridden financialised capitalism, regional development policies should consider the spatial implications of central bank interventions and recognise monetary policy as a key element of spatial policy. Simultaneously, monetary policy should embrace an explicit spatial agenda.
A Meta-analysis of Interactions Between Insect Herbivores and Plant-Parasitic Nematodes
Authors: Hauri Kayleigh C , Szendrei Zsofia
Published: October 2021

Insect herbivores and plant-parasitic nematodes are global, economically devastating pests that are present in nearly every crop and natural system worldwide. Although they may be spatially separated, they indirectly interact with each other by altering both plant chemical defense and nutrition. However, the outcome of these interactions is highly variable across different focal species. We performed a meta-analysis to determine how plant and nematode traits influence insect herbivore growth and reproduction, as well as nematode abundance and reproduction. We investigated how interactions between plant-parasitic nematodes and insect herbivores influence plant biomass, carbon, and nitrogen in the roots and shoots. We found no overall effect of nematodes on insect herbivores or insect herbivores on nematodes. However, while phloem-feeding insect reproduction was not affected by nematode feeding guild or plant family, chewing insect growth increased in the presence of cyst nematodes and decreased in the presence of gall nematodes. The effect of nematodes on chewing insect herbivore growth was also affected by the focal plant family. Nematode presence did not alter plant biomass when plants were exposed to aboveground insect herbivory, but carbon and nitrogen were higher in roots and nitrogen was higher in shoots of plants with nematodes and insects compared to plants with insects alone. Our results indicate that the mechanisms driving the outcome of aboveground–belowground interactions are still unclear, but those chewing insects may have more variable responses to nematode damage than phloem-feeders.
Anastomosis oversewing technique to prevent leakage after oesophagectomy: a propensity score-matched analysis
Authors: Tu De-Hao , Qu Rirong , Ping Wei , Yang Guang , Fu Xiangning , Cai Yixin
Published: October 2021

OBJECTIVES

Oesophagogastric anastomosis is a core part of oesophagectomy, and anastomotic leakage is among its main concerns. We used the oversewing technique to reinforce the anastomosis created with a circular stapler. This study investigated the use of oversewing to reduce the incidence of anastomotic leakage without increasing morbidity.

METHODS

This study enrolled 1734 patients who underwent oesophagectomy for oesophageal cancer between April 2012 and December 2019. Using propensity score-matched analysis, the clinical results of postoperative complications were compared between anastomotic-oversewn and -unsewn oesophagectomies.

RESULTS

Of the 1734 patients, 661 were included in the anastomotic-unsewn group and 661 in the anastomotic-oversewn group after propensity score matching. The clinical characteristics did not differ between the 2 groups, but the frequency of anastomotic leakage was significantly higher in the anastomotic-unsewn group than in the anastomotic-oversewn group (10.3% vs 4.7%, P < 0.001). Multivariable logistic analysis showed oversewn anastomosis and smoking history as the independent factors associated with anastomotic leakage (odds ratios, 0.399 and 2.383; P < 0.001 and P = 0.012, respectively). On the sub-group analysis, the relative risk for anastomotic leakage was significantly higher with unsewn than with oversewn anastomosis in patients <65 years old, those with American Association of Anesthesiologists score II, those who had middle segment oesophageal cancer and those who have undergone the McKeown approach and cervical anastomosis.

CONCLUSIONS

Anastomosis oversewing technique may be a practical method to reduce anastomotic leakage, especially in younger patients and those who have undergone the McKeown approach and cervical anastomosis.
Coping with COVID-19-related online English teaching challenges: teacher educators’ suggestions
Authors: Abdel Latif Muhammad M M
Published: October 2021

Although a number of studies have surveyed the challenges of remote English instruction imposed by COVID-19, a main research gap yet to be addressed is examining the relevant pedagogic experiences and suggestions given in language teacher educators’ blogs. Through analysing fifty-one blogs posted by teacher educators on four well-known language education websites, this study attempted to identify their perceived COVID-19-related online English language instruction challenges and suggested coping strategies. Analysing the blogs revealed nine main perceived online English teaching challenges associated with the teacher, learner, and online instruction implementation. To overcome these challenges, the teacher educators suggested seventeen main coping strategies pertinent to planning for online teaching, managing online classrooms, supporting students’ mental health, enhancing students’ ability to use/access technology, fostering active language learning engagement and motivation, and promoting teacher professional practices and wellbeing.