bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimization of power supply mode of single-mode laser diode by ratio of current and integral spectrum parameter
Authors: Berezovskaya N V , Bliznyuk V , Parshin V A , Tarasov A E
Published: December 2021

Bursting development of the technological base of semiconductor quantum electronics determined the width of the domain for use of semiconductor lasers in optical-electronic measuring systems based on the optical methods of stream research. In order to improve the accuracy of such systems, it is proposed to use a simple technique for optimizing the supply mode of a single-mode laser diode, based on an analysis of the current dependence of its integral spectral parameter. It is shown that the optimal value of the pumping current appears when the radiation spectrum envelope line tends to match the normalized Gaussian curve within the width of the spectral line.
Investigation of the phase delay of radiation by a transparent ferroelectric polymer film
Authors: Makeev M O , Osipkov A S , Batshev V I , Polschikova O V , Ryshkov N S , Kochervinskii V V , Yurkov G Yu
Published: December 2021

In this paper, we study samples of an optically transparent ferroelectric polymer film with deposited nanoscale electrically conductive coatings designed to modulate the transmitted electromagnetic radiation of the visible and near-infrared wavelengths. Such films can be used, for example, in interference devices for phase delay compensation or for the implementation of the Phase Shifting Interferometry, in adaptive optics, etc. To measure the phase delay of the radiation passing through the samples under study, an installation based on the Mach-Zehnder interferometer was used. In the illumination branch of the installation, a broadband radiation source and an acousto-optic tunable filter are installed; in one of the arms of the interferometer, the test sample is installed. The interference pattern was recorded on a matrix radiation receiver; the phase information was decoded by digital holography methods. The report presents the results of measurements and shows that a modulation of the passed optical radiation occurs under the influence of the electric field as a result of changes in the geometrical dimensions of the film.
Detection and study of polarized pulsed photoluminescence of diamonds for mapping of natural diamond
Authors: Krasin G K , Stsepuro N G , Kovalev M S , Danilov P A , Kudryashov S I
Published: December 2021

The bulk mapping of natural diamond poses problems where it is required to characterize various defects and measure their optical properties in volume. The combination of photoluminescence spectroscopy methods and methods for detecting the state of polarization in the volume will expand the functionality for mapping natural and artificial diamonds. The implemented methods will be an effective tool for the structural description of diamond optical centers.
Development of a high frequency ultrasonic setup for measuring the parameters of thin films
Authors: Martyanov P S , Zinin P V , Titov S A
Published: December 2021

In this report a novel method for measuring the elastic properties of thin 10 nm films is described. The method is based on the use of a nanosecond laser for generation acoustic waves in solids. Absorption of the incident laser pulse energy and the associated temperature gradients induces a rapidly changing strain field. This strain field, in turn, radiates energy as elastic (ultrasonic) waves. At low pulse power, this is an entirely thermo elastic process resulting in no damage to the sample. The acoustic echo arriving at the probed surface causes both the displacement of the surface (a few nanometres) and the strain in the subsurface material, which might be detected through the variation of the optical reflectivity of the material, i.e. through the acousto-optic effect.
Investigation of the interference pattern from a spherical particle at different viewing angles
Authors: Kuchmenko A V , Usmanova S S , Skornyakova N M , Kuchmenko V V
Published: December 2021

The work aim is to investigate the influence of the parameters of the laser interference method experimental setup on the obtained images. Using computer modeling based on the diffraction theory and physical experiment, the change in the parameters of the interference pattern for different viewing angles had been shown. The results can be used to develop a single algorithm for processing images of the laser interference method.
Optical system design of multispectral video camera for 8-14 microns range
Authors: Neverov S M
Published: December 2021

To solve the actual problem of determining the composition of a gas mixture in an uncontrolled leak at industrial sites, it is proposed to use a multispectral camera that allows you to simultaneously form several spectral images on a bolometric matrix. This method will provide visualization of the gas cloud in the far infrared range from 8 to 14 micrometers with selection by chemical composition. The article proposes an optical scheme for simultaneous registration of images in eight narrow spectral ranges of wavelengths, as well as the design of its elements for a bolometric matrix with a resolution of 640x480 pixels: a lens, a raster, and light filters using the ZEMAX application software package. As a result of the design, a low F-number three-lens optical system for a necessary field of view and a raster with a block of light filters are obtained, forming sixteen images in different spectral ranges. Thus, we solved an issue of design an optical system with minimal aberrations for a multispectral camera.
Detailed analysis of chemical corrosion of ultra-thin wires used in drift chamber detectors
Authors: Baldini A.M. , Cavoto G. , Cei F. , Chiappini M. , Chiarello G. , Chiri C. , Cocciolo G. , Corvaglia A. , Cuna F. , Francesconi M. , Galli L. , Grancagnolo F. , Grassi M. , Ishak R. , Meucci M. , Nicoló D. , Panareo M. , Papa A. , Pepino A. , Raffaelli F. , Renga F. , Ripiccini E. , Signorelli G. , Tassielli G.F. , Valentini R. , Voena C.
Published: December 2021

Ultra-thin metallic anode and cathode wires are frequently
employed in low-mass gaseous detectors for precision experiments,
where the amount of material crossed by charged particles must be
minimised. We present here the results of an analysis of the
mechanical stress and chemical corrosion effects observed in 40
and 50 μm diameter silver plated aluminum wires
mounted within the volume of the MEG II drift chamber, which caused
the breakage of about one hundred wires (over a total of
≈ 12000). This analysis is based on the careful inspection
of the broken wires by means of optical and electronic microscopes
and on a detailed recording of all breaking incidents. We present a
simple empirical model which relates the number of broken wires to
their exposure time to atmospheric relative humidity and to their
mechanical tension, which is necessary for mechanical stability in
the presence of electrostatic fields of several kV/cm. Finally we
discuss how wire breakages can be avoided or at least strongly
reduced by operating in controlled atmosphere during the mounting
stages of the wires within the drift chamber and by choosing a
25 % thicker wire diameter, which has very small effects on the
detector resolution and efficiency and can be obtained by using a
safer fabrication technique.
A gridded inventory of Canada’s anthropogenic methane emissions
Authors: Scarpelli Tia R , Jacob Daniel J , Moran Michael , Reuland Frances , Gordon Deborah
Published: December 2021

Canada’s anthropogenic methane emissions are reported annually to the United Nations Framework Convention on Climate Change through Canada’s National Inventory Report (NIR). Evaluation of this policy-relevant inventory using observations of atmospheric methane requires prior information on the spatial distribution of emissions but that information is lacking in the NIR. Here we spatially allocate the NIR methane emissions for 2018 on a 0.1° × 0.1° grid (≈10 km × 10 km) for individual source sectors and subsectors, with further resolution by source type for the oil/gas sector, using an ensemble of national and provincial geospatial datasets and including facility-level information from Canada’s Greenhouse Gas Reporting Program. The highest emissions are from oil/gas production and livestock in western Canada, and landfills in eastern Canada. We find 11 hotspots emitting more than 1 metric ton h−1 on the 0.1° × 0.1° grid. Oil sands mines in northeast Alberta contribute 3 of these hotspots even though oil sands contribute only 4% of national oil/gas emissions. Our gridded inventory shows large spatial differences with the EDGAR v5 inventory commonly used for inversions of atmospheric methane observations, which may reflect EDGAR’s reliance on global geospatial datasets. Comparison of our spatially resolved inventory to atmospheric measurements in oil/gas production fields suggests that the NIR underestimates these emissions. We also find strong spatial overlap between oil/gas, livestock, and wetland emissions in western Canada that may complicate source attribution in inversions of atmospheric data.
Geometric block-coherence and quantum state discrimination
Authors: Tang Danting , Li Ping , Ye Mingfei , Li Yongming
Published: December 2021

Quantum coherence with respect to orthonormal bases has been studied extensively in the past few years. From the perspective of operational meaning, geometric coherence can be equal to the minimum error probability to discriminate a set of pure states (2018 J. Phys. A: Math. Theor.
51 414005). By regarding coherence as a physical resource, Baumgratz et al (2014 Phys. Rev. Lett. 113 140401) presented a comprehensive framework for coherence. Recently, geometric block-coherence as an effective block-coherence measure has been proposed. In this paper, we reveal an equivalence relationship between mixed quantum state discrimination (QSD) task and geometric block-coherence, which provides an operational interpretation for geometric block-coherence and generalizes the main result in coherence resource theory. Meanwhile, we show that partial coherence is a special case of block-coherence. By linking the relationship between geometric partial coherence and QSD tasks, we show that the value range of the two measures is the same. Finally, we reveal the relationship between geometric positive operator-valued measure-based coherence and QSD task.
Nonlocality of a type of multi-star-shaped quantum networks
Authors: Yang Ying , Xiao Shu , Cao Huaixin
Published: December 2021

The correlations in quantum networks have attracted strong interest due to the fact that linear Bell inequalities derived from one source are useless for characterizing multipartite correlations of general quantum networks. In this paper, a type of multi-star-shaped quantum networks are introduced and discussed. Such a network consists of three-grade nodes: the first grade is named party (node) A, the second one consists of m nodes marked B
1, B
2, …, B

m
, which are stars of A and the third one consists of m
2 nodes

C

k

j

(

j
,
k
=
1
,
2
,
…
,
m

)

, where

C

k

j

(

k
=
1
,
2
,
…
,
m

)

are stars of B

j
. We call such a network a three-grade m-star quantum network and denoted by SQN(3, m), being as a natural extension of bilocal networks and star-shaped networks. We introduce and discussed the locality and strong locality of a SQN(3, m) and derive the related nonlinear Bell inequalities, called (3, m)-locality inequalities and (3, m)-strong locality inequalities. To compare with the bipartite locality of quantum states, we define the separability of SQN(3, m) that imply the locality and then locality of SQN(3, m). When all of the shared states of the network are pure ones, we prove that SQN(3, m) is nonlocal if and only if it is entangled.
Machine learning assisted GaAsN circular polarimeter
Authors: Aguirre-Perez A , Joshya R S , Carrère H , Marie X , Amand T , Balocchi A , Kunold A
Published: December 2021

We demonstrate the application of a two stage machine learning algorithm that enables one to correlate the electrical signals from a GaAs
x
N

1
−
x

circular polarimeter with the intensity, degree of circular polarization (DCP) and handedness of an incident light beam. Specifically, we employ a multimodal logistic regression to discriminate the handedness of light and a six-layer neural network (NN) to establish the relationship between the input voltages, the intensity and DCP. We have developed a particular NN training strategy that substantially improves the accuracy of the device. The algorithm was trained and tested on theoretically generated photoconductivity and on photoluminescence experimental results. Even for a small training experimental dataset (70 instances), it is shown that the proposed algorithm correctly predicts linear, right and left circularly polarized light, misclassifying less than

1.5
%

of the cases and attaining an accuracy larger than

97
%

in the vast majority of the predictions (

92
%

) for intensity and DCP. These numbers are significantly improved with larger theoretically generated datasets (4851 instances). The algorithm is versatile enough that it can be easily adjusted to other device configurations where a map needs to be established between the input parameters and the device response. Training and testing data files as well as the algorithm are provided as supplementary material.
Direct ink writing of 2D material-based supercapacitors
Authors: Tian Xiaocong
Published: December 2021

Atomically thin two-dimensional (2D) materials are excellent supercapacitor electrode candidates with intriguing physical and chemical properties. As a typical three-dimensional printing technique, direct ink writing (DIW) provides a new platform to bridge the gap between 2D materials and advanced supercapacitor electrodes. In the current review, recent progresses in DIW of 2D materials for supercapacitor applications are systematically presented, in which basic DIW processes, key scientific/technical points and corresponding strategies are highlighted. Ink fabrication and optimization based on 2D materials are discussed for supercapacitors, and recent advances in DIW of a variety of 2D material (including graphene, transition metal carbides and/or nitride (MXene), transition metal dichalcogenide and others)-based supercapacitor electrodes are offered. Furthermore, conclusions along with a brief discussion on challenges and opportunities of DIW-manufactured 2D materials are also provided for future supercapacitor applications.
Higher-order topological superconductivity from repulsive interactions in kagome and honeycomb systems
Authors: Li Tommy , Geier Max , Ingham Julian , D Scammell Harley
Published: December 2021

We discuss a pairing mechanism in interacting two-dimensional multipartite lattices that intrinsically leads to a second order topological superconducting state with a spatially modulated gap. When the chemical potential is close to Dirac points, oppositely moving electrons on the Fermi surface undergo an interference phenomenon in which the Berry phase converts a repulsive electron–electron interaction into an effective attraction. The topology of the superconducting phase manifests as gapped edge modes in the quasiparticle spectrum and Majorana Kramers pairs at the corners. We present symmetry arguments which constrain the possible form of the electron–electron interactions in these systems and classify the possible superconducting phases which result. Exact diagonalization of the Bogoliubov-de Gennes Hamiltonian confirms the existence of gapped edge states and Majorana corner states, which strongly depend on the spatial structure of the gap. Possible applications to vanadium-based superconducting kagome metals AV3Sb5(A = K, Rb, Cs) are discussed.
Role of enhanced surface grain refinement and hardness improvement induced by the combined effect of friction stir processing and ultrasonic impact treatment on slurry abrasive wear performance of silicon carbide particle reinforced A356 composites
Authors: Gençer Gökçe Mehmet , Kahraman Fatih , Yolcu Coşkun
Published: December 2021

In this study, the slurry abrasive wear behavior of silicon carbide particle reinforced A356 composite alloy was investigated after the different surface mechanical attrition treatments. It is known that the aluminum matrix composites produced by the stir casting method have some deficiencies (e.g unfavorable microstructure formation, particle clustering, porosity formation, etc). These kinds of drawbacks of the composites adversely affect the surface mechanical properties of materials such as wear resistance. For this purpose, the surface properties of the silicon carbide reinforced A356 matrix composites fabricated through the stir casting method were improved by using friction stir processing (FSP) and ultrasonic impact treatment (UIT) in the study. The results indicated that a remarkable increase was observed in the hardness and wear resistance of the cast composite via FSP and ultrasonic impact treatment following friction stir processing (FSP + UIT). The hardness of the stir zone after FSP and FSP + UIT was determined as 82.7+−2 HV and 101.9 +−3 HV0.2, respectively. The stir zone showed a similar tendency also in slurry abrasive wear resistance. FSP increased the wear resistance in the stir zone at the rate of 33.9% while it was determined as 35.5% for FSP + UIT. The microstructural modification of the cast composite that occurred after FSP was clearly demonstrated via optical microscope and scanning electron microscopy (SEM) examinations. Enhanced grain refinement after FSP + UIT was indicated especially by x-ray diffraction analysis (XRD). According to the findings, it was observed that the application of ultrasonic impact treatment following the friction stir processing can be used to obtain an enhanced microstructure and extra hardness increment in the surface of the SiC reinforced A356 alloy, thus resulting in slurry abrasive wear resistance increment.
Effect of homogenization on microstructure evolution and mechanical properties of aged Mg-Nd-Sm-Zn-Zr alloy
Authors: Ma Tao , Zhao Sicong , Wang Liping , Wang Zhiwei , Guo Erjun , Feng Yicheng , Liu Dongrong , Wu Changtong , Li Jingfang
Published: December 2021

As an indispensable pre-treatment for aging, homogenization treatment has a significant effect on precipitation behavior of the Mg-RE alloys. Herein, the influence of homogenization temperature on the microstructure evolution and mechanical performance of a novel Mg-2.0Nd-2.0Sm-0.4Zn-0.4Zr (wt.%) alloy has been studied systematically. The results indicated that the as-cast alloy was mainly composed of α-Mg matrix, β-Mg12(Nd,Sm,Zn) phase and Zr-containing particles. Upon increasing the homogenization temperature from 500 °C to 525 °C for 8 h, the average grain size of as-homogenized alloy increased from 76 μm to 156 μm, and the content of β phase decreased gradually. It was worth noting that the homogenization temperature exceeded 515 °C, the β phase at the grain boundaries was completely dissolved. After aging at 200 °C for 18 h, numerous of plate-like β′ phases were observed in α-Mg matrix. The rise in homogenization temperature was conducive to nucleation and growth of the β′ phase. However, excessive homogenization temperature significantly coarsened grain size. The aged alloy under homogenization treatment at 515 °C for 8 h achieved optimal mechanical properties. The values of ultimate tensile strength, yield strength and elongation were 261 MPa, 154 MPa and 5.8%, respectively. The fracture mode of the aged alloy mainly exhibited a typical transgranular cleavage fracture.
Structural stabilities, electronic structures, photocatalysis and optical properties of γ-GeN and α-SnP monolayers: a first-principles study
Authors: Liu Liming , Yan Cuixia , Gao Lei , Shangguan Wei , Dai Jianqing , Cai Jinming
Published: December 2021

Exploring two-dimensional materials with excellent photoelectricity properties is of great theoretical significance and practical value for developing new photocatalysts, electronics and photonic devices. Here, using first-principle calculations, we designed and analyzed systematically a series of α, β and γ phase structures of two-dimensional group IV-V monolayers (IV-V, IV = C, Si, Ge, Sn, Pb; V = N, P, As, Sb, Bi), most of them are semiconductors. Among them, γ-GeN and α-SnP monolayers with thermodynamic and kinetic stability (at 300 K) have been further studied due to their wide range of energy band gaps (γ-GeN: 2.54 eV, α-SnP:1.34 eV). The two band gaps are greater than the free energy for water splitting (1.23 eV), which are crucial for photocatalytic decomposition of water. The γ-GeN and α-SnP monolayers present excellent photocatalystics properties in pH = 0/7 and pH = 10 environments, respectively. Moreover, both of the monolayers show strong light absorption coefficients greater than 105 cm−1 in the visible and ultraviolet regions. In addition, it is found that the band edge positions and band gap sizes of γ-GeN and α-SnP monolayers can be regulated by biaxial strain. Benefitting from the wide selection of energy band gaps and high absorption coefficients, the γ-GeN and α-SnP monolayers are the next generation of promising candidate materials for photocatalysts, nanoelectronics and optoelectronics.
Mesoscopic simulation of overlapping behavior in laser powder bed additive manufacturing
Authors: Lu Pan , Tong Liu , Wen-Hao Wang , Yu Gao , Cheng-Lin Zhang , Jiang-Lin Liu
Published: December 2021

The prediction of the flow behavior of Metal micro-molten pool is prerequisite for high-quality Laser Powder Bed Fusion (L-PBF). In this study, mesoscopic scale numerical simulation modelling for L-PBF process was used to help understand the melting process of pure copper micro-melt pool. In this study, the orthogonal test was designed to study the influence of laser power, laser scanning velocity, hatching space on the flow behavior of molten pool and the overlapping rate of adjacent molten tracks. The results shows that laser scanning speed has the greatest influence on both the size and overlapping rate of the molten pool, and the overall trend was that the size of molten pool continues to increase as the volume energy density increases, and the maximum molten pool size was 243.6 um × 110 um with volume energy density 370.037 J mm−3, overlapping rate of adjacent molten tracks was 48.84% with volume energy density 285.71 J/mm3. The optimized pure copper laser process parameters were obtained: laser power 300 KW, laser scanning speed 500 mm/s, hatching space 0.07 mm, overlapping rate 48.84%.
Garment-integrated thermoelectric generator arrays for wearable body heat harvesting
Authors: Allison Linden K , Andrew Trisha L
Published: December 2021

Wearable thermoelectric generator arrays have the potential to use waste body heat to power on-body sensors and create, for example, self-powered health monitoring systems. In this work, we demonstrate that a surface coating of a conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT-Cl), created on one face of a wool felt using a chemical vapor deposition method was able to manifest a Seebeck voltage when subjected to a temperature gradient. The wool felt devices can produce voltage outputs of up to 120 mV when measured on a human body. Herein, we present a strategy to create arrays of polymer-coated fabric thermopiles and to integrate such arrays into familiar garments that could become a part of a consumer’s daily wardrobe. Using wool felt as the substrate fabric onto which the conducting polymer coating is created allowed for a higher mass loading of the polymer on the fabric surface and shorter thermoelectric legs, as compared to our previous iteration. Six or eight of these PEDOT-Cl coated wool felt swatches were sewed onto a backing/support fabric and interconnected with silver threads to create a coupled array, which was then patched onto the collar of a commercial three-quarter zip jacket. The observed power output from a six-leg array while worn by a healthy person at room temperature (ΔT = 15 °C) was 2 µW, which is the highest value currently reported for a polymer thermoelectric device measured at room temperature.
Prediction of the number of heatstroke patients transported by ambulance in Japan’s 47 prefectures: proposal of heat acclimatization consideration
Authors: Oka Kazutaka , Hijioka Yasuaki
Published: December 2021

The incidence of heatstroke is affected by various meteorological variables. However, previous studies in Japan have mainly investigated and adopted a single temperature metric or composite index for their analyses. Herein, we conducted a time series study through multivariate analysis of different weather conditions simultaneously, in order to analyze the relative importance of meteorological variables to determine the number of heatstroke patients transported by ambulance in all of Japan’s 47 prefectures. We proposed a method that considers heat acclimatization, which has been found to impact the heatstroke, by manipulating certain meteorological variables. For the heatstroke data, we utilized the secondary data provided by the Fire and Disaster Management Agency, Japan. The time period considered was from May 2015 to September 2019. All calculations were performed using R 3.5.1. For the analysis, the machine learning method of random forest (RF) was applied. The results showed that the relative temperature (RelTemp), which represents heat acclimatization, had the highest ranking among all the meteorological variables studied. Then, we developed the exponential model and the RF model to predict the number of heatstroke patients transported by ambulance by adopting the highly ranked meteorological variables including RelTemp as explanatory variables. To confirm the effectiveness of heat acclimatization, we also developed the exponential model and the RF model both without RelTemp (instead, with maximum temperature). According to the results, the R2 values of the exponential and the RF models, including RelTemp, were 0.76 and 0.74, respectively, and those of the exponential and the RF models, excluding RelTemp, were 0.68 and 0.67, respectively. We confirmed the effectiveness of considering heat acclimatization via RelTemp and found that the exponential model with RelTemp provided the higher accuracy. Better predictions by the exponential model with RelTemp would contribute to better preemptive allocation of ambulances and medical staff in medical facilities.
Contrasting scaling relationships of extreme precipitation and streamflow to temperature across the United States
Authors: Shen Mingxi , Chui Ting Fong May
Published: December 2021

Recent studies have reached inconsistent conclusions from scaling analysis about whether flood or extreme precipitation is more sensitive to warming climate. To explain the reasons behind the inconsistency, here we first used scaling analysis to illustrate how extreme daily precipitation and streamflow scale with daily air temperature across the Continental United States (CONUS). We found both similar and opposite scaling in extreme precipitation and streamflow. It indicates based on scaling analysis, the sensitivity of extreme streamflow to warming climate can be either similar, higher or lower to that of extreme precipitation. We further explored why there are contrasting scaling relationships in the CONUS. Generally, the similar scaling was found in regions where the timing of extreme precipitation and streamflow is correspondent, as well as with similar temporal evolution in extreme event timing and magnitude, e.g., the west coast and southern plains, implying extreme precipitation is the dominant driver of local floods. However, for regions with dissimilar scaling in extreme precipitation and streamflow (e.g., Rocky Mountains, southern plains), the characteristics of extreme streamflow show large difference to those of extreme precipitation, and the temporal evolution of extreme streamflow timing and magnitude are more correlated with factors/processes such as soil moisture and snowmelt. This study reflects that the contrasting scaling relationships of extreme precipitation and streamflow are oriented from the local hydro-climatological specifics. Using scaling analysis to compare the sensitivity of extreme precipitation and streamflow to warming climate is not suitable. Instead, we should focus more on local flood generating mechanisms or flood drivers when investigating floods in the changing climate.
Guided acceleration of nanoparticles by laser irradiated parallel gold nanorods
Authors: Yadav Mamta , Kumar Ashok , Mandal Subhayan
Published: December 2021

Laser irradiated parallel gold nanorods with interspersed deuterium nanoparticles are shown to offer guided acceleration of nanoparticles. The laser pulse of intensity exceeding 1018 W cm−2 at 1 μm wavelength and pulse duration ∼30 fs causes full ionization of nanoparticles and high state ionization of gold atoms and pushes out the free electrons via the ponderomotive force. The charged nanorods have an electric field that has transverse component towards the axis of symmetry and axial field outwards. Thus the nanoparticles are accelerated axially while confined transversely. Deuterium beam of a few MeV energy can be produced by this technique.
Study of the effect of nano ZrO2 and TiO2 and rotation speed on friction behavior of rotary friction welding of HIPS and PP
Authors: Afzali Mohammad , Asghari Vahid
Published: December 2021

The purpose of this project was to introduce a way to improve the mechanical properties of dissimilar welded material, which provides benefits such as affordability, high speed, and a suitable bond property. This experimental project applies the friction welding method, including combining parameters, such as a numerical control machine, two different speeds, and three different cross sections, including flat, cone, and step surfaces. When the welding process was done, samples were implemented and prepared via a bending test of materials. The results have shown that, besides increasing the machining velocity, the surface friction increased, and so did the temperature. Considering the stated experimental facts, the melting temperature of composite materials increased. This provides the possibility of having a better blend of nanomaterial compared to the base melted plastics. Thus, the result showed that, besides increasing the weight percentage of nanomaterial contents and machining velocity, the mechanical properties increased on the welded area for all three types of samples. This enhancement is due to the better melting process on the welded area with the attendance of various nanoparticle contents. Also, the results showed that the shape of the welding area could play a significant role, and the results also change drastically where the shape changes. Optimum shape in the welding process has been dedicated to the step surface. The temperature causes the melting process, which is a significant factor in the friction welding process.
High mobility SiMOSFETs fabricated in a full 300 mm CMOS process
Authors: Camenzind T N , Elsayed A , Mohiyaddin F A , Li R , Kubicek S , Jussot J , Van Dorpe P , Govoreanu B , Radu I , Zumbühl D M
Published: December 2021

The quality of the semiconductor–barrier interface plays a pivotal role in the demonstration of high quality reproducible quantum dots for quantum information processing. In this work, we have measured SiMOSFET Hall bars on undoped Si substrates in order to investigate the device quality. For devices fabricated in a full complementary metal oxide semiconductor (CMOS) process and of very thin oxide below a thickness of 10 nm, we report a record mobility of 17.5 × 103 cm2 V−1 s−1 indicating a high quality interface, suitable for future qubit applications. We also study the influence of gate materials on the mobilities and discuss the underlying mechanisms, giving insight into further material optimization for large scale quantum processors.
A multi-pronged investigation of option generation using depression, PET and modafinil
Authors: Ang Yuen-Siang , Cusin Cristina , Petibon Yoann , Dillon Daniel G , Breiger Micah , Belleau Emily L , Normandin Marc , Schroder Hans , Boyden Sean , Hayden Emma , Levine M Taylor , Jahan Aava , Meyer Ashley K , Kang Min Su , Brunner Devon , Gelda Steven E , Hooker Jacob , El Fakhri Georges , Fava Maurizio , Pizzagalli Diego A
Published: December 2021

Option generation is a critical process in decision making, but previous studies have largely focused on choices between options given by a researcher. Consequently, how we self-generate options for behaviour remain poorly understood. Here, we investigated option generation in major depressive disorder and how dopamine might modulate this process, as well as the effects of modafinil (a putative cognitive enhancer) on option generation in healthy individuals.

We first compared differences in self-generated options between healthy non-depressed adults [n = 44, age = 26.3 years (SD 5.9)] and patients with major depressive disorder [n = 54, age = 24.8 years (SD 7.4)]. In the second study, a subset of depressed individuals [n = 22, age = 25.6 years (SD 7.8)] underwent PET scans with 11C-raclopride to examine the relationships between dopamine D2/D3 receptor availability and individual differences in option generation. Finally, a randomized, double-blind, placebo-controlled, three-way crossover study of modafinil (100 mg and 200 mg), was conducted in an independent sample of healthy people [n = 19, age = 23.2 years (SD 4.8)] to compare option generation under different doses of this drug.

The first study revealed that patients with major depressive disorder produced significantly fewer options [t(96) = 2.68, P = 0.009, Cohen’s d = 0.54], albeit with greater uniqueness [t(96) = −2.54, P = 0.01, Cohen’s d = 0.52], on the option generation task compared to healthy controls. In the second study, we found that 11C-raclopride binding potential in the putamen was negatively correlated with fluency (r = −0.69, P = 0.001) but positively associated with uniqueness (r = 0.59, P = 0.007). Hence, depressed individuals with higher densities of unoccupied putamen D2/D3 receptors in the putamen generated fewer but more unique options, whereas patients with lower D2/D3 receptor availability were likely to produce a larger number of similar options. Finally, healthy participants were less unique [F(2,36) = 3.32, P = 0.048, partial η2 = 0.16] and diverse [F(2,36) = 4.31, P = 0.021, partial η2 = 0.19] after taking 200 mg versus 100 mg and 0 mg of modafinil, while fluency increased linearly with dosage at a trend level [F(1,18) = 4.11, P = 0.058, partial η2 = 0.19].

Our results show, for the first time, that option generation is affected in clinical depression and that dopaminergic activity in the putamen of patients with major depressive disorder may play a key role in the self-generation of options. Modafinil was also found to influence option generation in healthy people by reducing the creativity of options produced.
MiR-145 modulates the radiosensitivity of non-small cell lung cancer cells by suppression of TMOD3
Authors: Li Hang , Zhao Shuya , Chen Xin , Feng Guoxing , Chen Zhiyuan , Fan Saijun
Published: December 2021

Radioresistance is a major problem encountered in the treatment of non-small cell lung cancer (NSCLC). Aberrant microRNA (miRNA) expression contributes to multiple cancer-associated signaling pathways and profoundly influences effects of radiotherapy (RT) in cancers. MicroRNA-145-5p (miR-145) is recognized as a tumor suppresser in NSCLC. However, the roles of miR-145 during radiotherapy of NSCLC are largely unknown. The present study aimed to investigate the function and underlying mechanism of miR-145 in modulation of radiosensitivity in NSCLC. We generated radioresistant H460 and A549 subclones, named H460R and A549R, respectively, and found that irradiation (IR) could suppress the expression levels of miR-145 in radioresistant NSCLC cells. Furthermore, overexpression of miR-145 could sensitize radioresistant NSCLC cells to IR, whereas knockdown of miR-145 in NSCLC cells acted the converse manner. Mechanically, miR-145 was able to directly target 3′UTR of tropomodulin 3 (TMOD3) mRNA and decrease the expression of TMOD3 at the levels of mRNA and protein. Additionally, we confirmed that miR-145 could enhance the radiosensitivity of radioresistant NSCLC cells by targeting TMOD3 in vitro and in vivo, and could be used as a target in clinical treatment of NSCLC. Collectively, restoration of miR-145 expression increases the radiosensitivity of radioresistant NSCLC cells by suppression of TMOD3, and miR-145 can act as a new radiosensitizer for NSCLC therapy.
Decolonizing Climate Research and Policy: making space to tell our own stories, in our own ways
Authors: Deranger Eriel Tchekwie , Sinclair Rebecca , Gray Beze , McGregor Deborah , Gobby Jen
Published: December 2021

As the climate crisis deepens, the discourse aimed at finding solutions continues to intensify. Increasingly, government agencies and world leaders are recognizing the critical importance of including Indigenous knowledge and perspectives in the development of sustainable responses. To date, however, opportunities for meaningful Indigenous engagement in the creation and development of climate solutions remain few and far between. Where such opportunities do exist, they are most often designed with the intention of trying to `incorporate' limited elements of Indigenous thinking into an established non-Indigenous framework. This process of `Indigenizing' mainstream initiatives achieves little if anything in the way of deconstructing the colonial world view that has caused the climate crisis in the first place. Actively decolonizing Canada's and the world's responses to climate change is absolutely necessary if global society is to achieve the `transformation' of our economies and societies deemed essential for our survival by the United Nations Intergovernmental Panel on Climate Change (IPCC), among others. No longer can we afford to simply `tweak the system' by slotting into mainstream processes those elements of Indigenous world view that seem to `fit' most comfortably. If we continue to value the colonial system of neoliberalism and runaway capitalism over those proven sustainable paradigms wherein respect for all life is paramount, then no lasting solutions are possible. Instead, we need to `flip the script', and start providing spaces wherein Indigenous thinking and world view provide the fundamental framework, and non-Indigenous ideas that align sufficiently with Indigenous principles may be incorporated as appropriate. This article recounts a panel discussion, hosted by Indigenous Climate Action, in which four influential Indigenous climate researchers, organizers and policy experts share their reflections on how climate research and policy can be actively decolonized. The panelists draw on their experiences to engage and encourage the audience, listeners, and readers to explore ways to decolonize their own perspectives and to support climate solutions inclusive of all People.
Catching wandering minds with tapping fingers: neural and behavioral insights into task-unrelated cognition
Authors: Groot Josephine M , Csifcsák Gábor , Wientjes Sven , Forstmann Birte U , Mittner Matthias
Published: December 2021

When the human mind wanders, it engages in episodes during which attention is focused on self-generated thoughts rather than on external task demands. Although the sustained attention to response task is commonly used to examine relationships between mind wandering and executive functions, limited executive resources are required for optimal task performance. In the current study, we aimed to investigate the relationship between mind wandering and executive functions more closely by employing a recently developed finger-tapping task to monitor fluctuations in attention and executive control through task performance and periodical experience sampling during concurrent functional magnetic resonance imaging (fMRI) and pupillometry. Our results show that mind wandering was preceded by increases in finger-tapping variability, which was correlated with activity in dorsal and ventral attention networks. The entropy of random finger-tapping sequences was related to activity in frontoparietal regions associated with executive control, demonstrating the suitability of this paradigm for studying executive functioning. The neural correlates of behavioral performance, pupillary dynamics, and self-reported attentional state diverged, thus indicating a dissociation between direct and indirect markers of mind wandering. Together, the investigation of these relationships at both the behavioral and neural level provided novel insights into the identification of underlying mechanisms of mind wandering.
The robustness of the photosynthetic system I energy transfer complex network to targeted node attack and random node failure
Authors: Bellingeri M , Montepietra D , Cassi D , Scotognella F
Published: December 2021

In this article, we implement and compare 10 node removal (attack) strategies from the literature over the photosystem I (PSI) complex network of the common pea plant (Pisum sativum), representing the FRET energy transfer among its nodes/chromophores. We measure the network robustness (functioning) with four indicators. The node attack strategies and the network robustness indicators consider both the binary-topological and the weighted structure of the network. First, we find that the well-known node betweenness centrality attack, which has proven highly effective in dismantling most real-world networks’ topological connectivity, is ineffective over the PSI network. Second, the degeneracy of the node properties caused by the PSI’s higher network connectivity level induces a random-like node removal even when nodes are removed according to a specific node centrality measure. This phenomenon triggers a very low decrease of the PSI network functioning even when subjected to node attack. Such an outcome would indicate that the node attack strategies based on classic node properties, such as the degree or the betweenness centrality, may show low efficacy in dismantling real-world networks with very high connectivity levels.

Last, the PSI network can be built by tuning a cut-off distance (CD) that defines the viable energy transfers among nodes/chromophores and progressively discards the lower energy transfer links among distant nodes/chromophores. This represents a ‘weight thresholding’ procedure allowing us to investigate the efficacy of the node attack strategies when links of lower weight are progressively pruned from the PSI network. We find that the best node attack strategies change by decreasing the CD, showing that the weight thresholding procedure affects the network response to node removal. This last outcome outlines the importance of investigating the stability of the system response for real-world weighted complex networks subjected to the weight thresholding procedure.
Patterns of cortisol and corticosterone concentrations in humpback whale (Megaptera novaeangliae) baleen are associated with different causes of death
Authors: Lowe Carley L , Hunt Kathleen E , Robbins Jooke , Seton Rosemary E , Rogers Matthew , Gabriele Christine M , Neilson Janet L , Landry Scott , Teerlink Suzie S , Buck C Loren
Published: December 2021

Baleen whales are subject to a myriad of natural and anthropogenic stressors, but understanding how these stressors affect physiology is difficult. Measurement of adrenal glucocorticoid (GC) hormones involved in the vertebrate stress response (cortisol and corticosterone) in baleen could help fill this data gap. Baleen analysis is a powerful tool, allowing for a retrospective re-creation of multiple years of GC hormone concentrations at approximately a monthly resolution. We hypothesized that whales that died from acute causes (e.g. ship strike) would have lower levels of baleen GCs than whales that died from extended illness or injury (e.g. long-term entanglement in fishing gear). To test this hypothesis, we extracted hormones from baleen plates of four humpback whales (Megaptera novaeangliae) with well-documented deaths including multiple and chronic entanglements (n = 1, female), ship strike (n = 2, male and female) and chronic illness with nutritional stress (n = 1, male). Over ~3 years of baleen growth and during multiple entanglements, the entangled whale had average corticosterone levels of 80–187% higher than the other three whales but cortisol levels were similar to two of the other three whales. The nutritionally stressed and chronically ill whale showed a slow increase in both cortisol and corticosterone spanning ~3 years, followed by a sharp decline in both hormones before death, possibly indicative of adrenal failure in this moribund individual. This whale’s correlation between cortisol and corticosterone was significant but there were no correlations in the other three whales. Our results show that cortisol and corticosterone concentrations vary according to the type and duration of illness or injury. Single-point GC concentrations should be interpreted with caution as low values can occur in whales experiencing pronounced stress and individual baselines can be highly variable. Baleen analysis is a promising tissue type for retrospective analyses of physiological responses to various stressors affecting baleen whales.
Inflammatory Bowel Disease Patients’ Perspectives of Clinical Trials: A Global Quantitative and Qualitative Analysis
Authors: Rubin David T , Peyrin-Biroulet Laurent , Reinisch Walter , Tole Swati , Sullivan Laura , Park K T , Regueiro Miguel
Published: December 2021

Background

Despite recent progress, inflammatory bowel disease (IBD) therapies with pronounced long-term efficacy and improved safety are needed. IBD clinical trials face challenges with patient recruitment because of study designs, competitive or overlapping trials, and limited numbers of eligible patients. We aimed to better understand patients’ awareness of, attitudes toward, and experience with IBD clinical trials.

Methods

This multinational, cross-sectional cohort study of adults with IBD recruited online consisted of 2 components: a quantitative 15-minute online survey completed by all participants and a qualitative 30-minute telephone interview completed by a subset of patients from the United States.

Results

Quantitative survey respondents (N = 226) included patients with ulcerative colitis (52%) and Crohn’s disease (48%) from the United States (n = 100, 21 of whom were interviewed), Brazil (n = 26), Canada (n = 25), France (n = 25), Germany (n = 25), and Spain (n = 25); 96% of respondents reported at least a basic understanding of clinical trials. Patients rated conversations with health care providers most helpful for researching trials, but during interviews patients discussed their desire for increased patient–physician communication about trials. Major barriers to participation included invasive screening/monitoring (35% of quantitative responses) and concern over receiving placebo (35%) or suboptimal treatment (33%). Most respondents (68%) reported that clinical trial participants are “guinea pigs” for an experimental treatment.

Conclusions

Opportunities to improve participation in IBD trials include improved communication with health care providers, further patient education, and alternative trial designs. Ultimately, a better understanding of the patient perspective will be important for more informed patients and more successful recruitment and enrollment.