bluuebunny/crossref_metadata_2025 huggingface dataset:
Shock initiation of low density polymer bonded explosive LX-14: A study of two morphologies
Authors: Burns M. J.
Published: April 2022

A series of six shock initiation experiments have been carried out on low density LX-14 powder in order to simulate a shock insult on the heavily damage polymer bonded explosive, LX-14. Two distinct morphologies were studied (tap density molding powder and machined swarf), both at the same density of 0.942 g/cm3, or 50.1% theoretical maximum density. The purpose of these experiments was to provide data to help make an assessment of the effects that damage has on the material sensitivity to a planar shock. This was achieved primarily by providing shock sensitivity data in the form of a Pop plot, and also reactants equation of state data, which aids in the determination of input conditions for both the experiments performed in this work and also future experiments of this material type. The experiments were of a cut-back format, consisting of four sample heights on each shot and diagnosed with optical velocimetry. The experiments were carried out at the Technical Area 40 Chamber 9 gas gun facility at the Los Alamos National Laboratory, where the LX-14 targets were subjected to Al 6061 and Oxygen Free High Conductivity copper impactors launched to velocities up to 2.14 km/s. Time corrected reactive growth wave profiles are presented in this paper along with the derivation of the following Hugoniot parameters for this explosive, where the molding powder and machine swarf are represented by the following linear equations, respectively, US=1.64(±0.64)up+2.25(±0.49) and US=0.87(±0.60)up+4.08(±0.49). The results show that the steady increase in shock sensitivity with increasing void fraction reaches an inflection point beyond which the shock sensitivity begins to decease. This inflection point lies between 65% and 50% of the theoretical maximum density of the LX-14. In both cases, the damaged LX-14 was not as sensitive as expected, with a relative shock sensitivity of the molding powder being less than the pressed LX-14, and the machined swarf having a shock sensitivity that is comparable to pressed LX-14.
Nonlinear characteristics and corrections of near-field underwater explosion shock waves
Authors: Jia Xiyu , Wang Shushan , Xu Jie , Zhang Jingxiao , Gao Yuan , Ma Feng
Published: April 2022

The shock wave characteristics within the near-field are one of the most challenging aspects of understanding an underwater explosion. The latest numerical and experimental techniques were utilized to investigate the near-field pressure distribution and decay features after a shock disturbance. The governing equations in the numerical simulation were discretized with a fifth-order weighted essentially non-oscillatory scheme in space and a third-order Runge–Kutta scheme in time, and multi-medium interactions were defined and resolved via the modified ghost fluid method. The test system consisted of a synchronized high-speed framing camera and polyvinylidene fluoride (PVDF) sensors. Three identical spherical composition B charges were examined under the same test conditions, and the raw data from the high-speed camera were processed with edge detection and circle fitting techniques. The comparison showed that the high-speed camera image data, the PVDF signals, and the numerical computation results were highly consistent with each other. Higher-order correction terms were added to the pressure peak distribution model and the pressure decay model as nonlinear corrections based on further comprehensive and insightful analysis of the verified results. The corrected models not only fit with the near-field data but had better accuracy under the far-field condition as well.
Experimental identification of topography-based artifact phenomenon for micro-/nanoscale thermal characterization of polymeric materials in scanning thermal microscopy
Authors: Dong Lan , Li Yifan
Published: April 2022

Scanning thermal microscopy (SThM) is capable of collecting topography feedback and probing qualitative thermal properties simultaneously. Although topography and thermal feedback signals are obtained from two independent loops without affecting each other, thermal feedback can be distorted by topography feedback, resulting in a topography-related thermal signal, defined as the artifact phenomenon. Based on this situation, the instrument thermal response is no longer accurate, and the intrinsic generation reason and affecting factors of the artifact are still not clear. In this work, different polymeric-based materials were prepared to construct varied contact geometries at the tip/sample contact interface. Identification of the artifact was performed based on the investigation of corresponding topography and thermal feedback. Generation mechanisms of the artifact were further proposed aiming at different contact situations. This work not only clarifies the generation reason and affecting factors of the artifact but also suggests the sample preparation requirements for the eliminated artifact and accurate thermal characterization through SThM.
An Onsager–Machlup approach to the most probable transition pathway for a genetic regulatory network
Authors: Hu Jianyu , Chen Xiaoli , Duan Jinqiao
Published: April 2022

We investigate a quantitative network of gene expression dynamics describing the competence development in Bacillus subtilis. First, we introduce an Onsager–Machlup approach to quantify the most probable transition pathway for both excitable and bistable dynamics. Then, we apply a machine learning method to calculate the most probable transition pathway via the Euler–Lagrangian equation. Finally, we analyze how the noise intensity affects the transition phenomena.
Evaluation of U.S. State Opioid Prescribing Restrictions Using Patient Opioid Consumption Patterns from a Single, Urban, Academic Institution
Authors: Robinson Kortney A. , Marwaha Jayson S. , Kennedy Chris J. , Beaulieu-Jones Brendin R. , Fleishman Aaron , Yu Justin K. , Nathanson Larry A. , Brat Gabriel A.
Published: April 2022

Background:Since 2017, states, insurers, and pharmacies have placed blanket limits on the duration and quantity of opioid prescriptions. In many states, overlapping duration and daily dose limits yield maximum prescription limits of 150–350 morphine milligram equivalents (MMEs). There is limited knowledge of how these restrictions compare with actual patient opioid consumption; while changes in prescription patterns and opioid misuse rates have been studied, these are, at best, weak proxies for actual pain control consumption. We sought to determine how patients undergoing surgery would be affected by opioid prescribing restrictions using actual patient opioid consumption data. Methods: We constructed a prospective database of post-discharge opioid consumption: patients undergoing surgery at one institution were called after discharge to collect opioid consumption data. Patients whose opioid consumption exceeded 150 and 350 MME were identified. Results: Two thousand nine hundred and seventy-one patients undergoing 54 common surgical procedures were included in our study. Twenty-one percent of patients consumed more than the 150 MME limit. Only 7% of patients consumed above the 350 MME limit. Typical (non-outlier) opioid consumption, defined as less than the 75th percentile of consumption for any given procedure, exceeded the 150 MME and 350 MME limits for 41 and 7% of procedures, respectively. Orthopedic, spinal/neurosurgical, and complex abdominal procedures most commonly exceeded these limits. Conclusions: While most patients undergoing surgery are unaffected by recent blanket prescribing limits, those undergoing a specific subset of procedures are likely to require more opioids than the restrictions permit; providers should be aware that these patients may require a refill to adequately control post-surgical pain. Real consumption data should be used to guide these restrictions and inform future interventions so the risk of worsened pain control (and its troublesome effects on opioid misuse) is minimized. Procedure-specific prescribing limits may be one approach to prevent misuse, while also optimizing post-operative pain control.
Is it racism? The belief in cultural superiority across Europe
Authors: Bratt Christopher
Published: April 2022

Are Europeans racist if they maintain that some cultures are superior? Theorists of cultural racism argue so and suggest that modern racism in Europe is expressed as a belief in cultural superiority. But this claim has been based on theoretical arguments, not on empirical tests. The current research investigated how widespread a belief in cultural superiority was in European countries and tested how such a belief related to biological racism. Analyses of data from the European Social Survey (21 countries, total N > 33,000) showed large differences across countries in tendencies to endorse the belief in cultural superiority. But in nearly all countries, a factor model consistent with the theory of cultural racism had much better support than a factor model building on the assumption that culturalism is distinct from racism. Even when the factor analysis was able to maintain a distinction between racism and culturalism, the two factors had a very strong correlation. The present research suggests that although a belief in cultural superiority may harbour different views, expressed beliefs in cultural superiority and cultural concerns are strongly associated with traditional racism.
“If I Didn’t Have Them, I’m Not Sure How I Would Have Coped with Everything Myself”: Empowering and Supporting Parents/Carers of High-Risk Young People Assisted by Community Forensic CAMHS
Authors: Jacob Jenna , Lane Rebecca , D’Souza Sophie , Cracknell Liz , White Oliver , Edbrooke-Childs Julian
Published: April 2022

Parent/carer involvement in their child’s support for mental health difficulties is a critical component of effective care. 13 Community Forensic Child and Adolescent Mental Health Services (F:CAMHS) across England were developed to provide specialist support to young people at high risk of harm to self and in particular others, and their families. The aim of this study is to explore parent/carer experiences of Community F:CAMHS. Thematic analysis of interviews (N = 18, from 5 sites) was conducted. Superordinate themes generated focused on 1) facilitators; and 2) barriers to support. Subthemes generated relate primarily to facilitators, particularly empowering parents/carers through the co-production of strategies to help, “holding” cases (taking ownership), and acting on behalf of and supporting parents/carers. Managing clear, joined-up communication across multi-agencies is also of key importance. Barriers to effective support are a lack of joined-up communication at the beginning of the implementation of the services, awareness of Community F:CAMHS, and limited contact. Implications, including the need to further embed the Community F:CAMHS offering in the overall provision of support for this population are discussed. Areas for future research are identified, including the exploration of how young people's characteristics and outcomes may impact parents/carers’ experiences of interacting with services.
Effect of ischemic preconditioning on maximum accumulated oxygen deficit in 400‐meter runners
Authors: Chen Yuyang , Yang Junchao , Muradov Orhan , Li Xinyuan , Lee Jason Kai Wei , Qiu Junqiang
Published: April 2022

The main aim of this study was to examine the influence of ischemic preconditioning (IPC) on maximal accumulated oxygen deficit (MAOD). We conducted a three‐arm and assessor‐blinded randomized, controlled crossover study. Sixteen 400‐meter running male athletes (19.9 ± 1.3 years; 1.78 ± 0.05 m; 67.9 ± 5.5 kg) completed three supramaximal intensity tests separated with Control, Local (legs), and Remote (arms) IPC interventions. IPC was induced on the limbs on both sides (4×5 min alternating unilateral occlusion 220 mmHg and reperfusion; arms or thighs; right side first) before participants performed the supramaximal intensity test on a treadmill at 110% VO2max intensity to exhaustion. During each test, indices of respiratory gas exchange, blood lactate, and heart rate were determined. The MAOD was calculated as the difference between the theoretical VO2 demand and the actual VO2 during the supramaximal intensity test. Differences from three trials were analyzed using ANOVA with repeated measures. IPC increased MAOD (RIPC, 59 ± 17 ml/kg/min, p = 0.018; LIPC, 57 ± 15 ml/kg/min, p = 0.037; p < 0.05) compared with Control (49 ± 9 ml/kg/min). Time to exhaustion was enhanced after IPC (Control: 257.2 ± 69.5 s, RIPC, 292.3 ± 66.6 s, p = 0.048; LIPC, 291.6 ± 79.2 s, p = 0.042; p < 0.05). In contrast, the enhancements of RIPC and LIPC trials were similar (p = 1.000). Blood lactate concentrations were similar across the three intervention conditions (p > 0.05). Acute IPC improved MAOD and supramaximal intensity exercise capacity in 400‐meter running athletes. The increased MAOD indicated greater anaerobic capacity, which can be the potential mediator for improvement in exhaustion time.

Highlights

Ischemic preconditioning may improve the exhaustion time of supramaximal intensity running in well‐trained 400‐meter middle distance athletes.

Acute IPC may be beneficial to anaerobic exercise capacity as the maximal accumulated oxygen deficit increases after IPC.

Acute IPC occlusion on the upper arms or thighs may improve anaerobic capacity.
Actomyosin activity-dependent apical targeting of Rab11 vesicles reinforces apical constriction
Authors: Chen Wei , He Bing
Published: April 2022

During tissue morphogenesis, the changes in cell shape, resulting from cell-generated forces, often require active regulation of intracellular trafficking. How mechanical stimuli influence intracellular trafficking and how such regulation impacts tissue mechanics are not fully understood. In this study, we identify an actomyosin-dependent mechanism involving Rab11-mediated trafficking in regulating apical constriction in the Drosophila embryo. During Drosophila mesoderm invagination, apical actin and Myosin II (actomyosin) contractility induces apical accumulation of Rab11-marked vesicle-like structures (“Rab11 vesicles”) by promoting a directional bias in dynein-mediated vesicle transport. At the apical domain, Rab11 vesicles are enriched near the adherens junctions (AJs). The apical accumulation of Rab11 vesicles is essential to prevent fragmented apical AJs, breaks in the supracellular actomyosin network, and a reduction in the apical constriction rate. This Rab11 function is separate from its role in promoting apical Myosin II accumulation. These findings suggest a feedback mechanism between actomyosin activity and Rab11-mediated intracellular trafficking that regulates the force generation machinery during tissue folding.
CPAP insufficiency leads to incomplete centrioles that duplicate but fragment
Authors: Vásquez-Limeta Alejandra , Lukasik Kimberly , Kong Dong , Sullenberger Catherine , Luvsanjav Delgermaa , Sahabandu Natalie , Chari Raj , Loncarek Jadranka
Published: April 2022

Centrioles are structures that assemble centrosomes. CPAP is critical for centrosome assembly, and its mutations are found in patients with diseases such as primary microcephaly. CPAP’s centrosomal localization, its dynamics, and the consequences of its insufficiency in human cells are poorly understood. Here we use human cells genetically engineered for fast degradation of CPAP, in combination with superresolution microscopy, to address these uncertainties. We show that three independent centrosomal CPAP populations are dynamically regulated during the cell cycle. We confirm that CPAP is critical for assembly of human centrioles, but not for recruitment of pericentriolar material on already assembled centrioles. Further, we reveal that CPAP insufficiency leads to centrioles with incomplete microtubule triplets that can convert to centrosomes, duplicate, and form mitotic spindle poles, but fragment owing to loss of cohesion between microtubule blades. These findings further our basic understanding of the role of CPAP in centrosome biogenesis and help understand how CPAP aberrations can lead to human diseases.
CCR2/CCR5 inhibitor permits the radiation-induced effector T cell infiltration in pancreatic adenocarcinoma
Authors: Wang Jianxin , Saung May Tun , Li Keyu , Fu Juan , Fujiwara Kenji , Niu Nan , Muth Stephen , Wang Junke , Xu Yao , Rozich Noah , Zlomke Haley , Chen Sophia , Espinoza Birginia , Henderson MacKenzie , Funes Vanessa , Herbst Brian , Ding Ding , Twyman-Saint Victor Christina , Zhao Qihong , Narang Amol , He Jin , Zheng Lei
Published: April 2022

The resistance of pancreatic ductal adenocarcinoma (PDAC) to immune checkpoint inhibitors (ICIs) is attributed to the immune-quiescent and -suppressive tumor microenvironment (TME). We recently found that CCR2 and CCR5 were induced in PDAC following treatment with anti–PD-1 antibody (αPD-1); thus, we examined PDAC vaccine or radiation therapy (RT) as T cell priming mechanisms together with BMS-687681, a dual antagonist of CCR2 and CCR5 (CCR2/5i), in combination with αPD-1 as new treatment strategies. Using PDAC mouse models, we demonstrated that RT followed by αPD-1 and prolonged treatment with CCR2/5i conferred better antitumor efficacy than other combination treatments tested. The combination of RT + αPD-1 + CCR2/5i enhanced intratumoral effector and memory T cell infiltration but suppressed regulatory T cell, M2-like tumor–associated macrophage, and myeloid-derived suppressive cell infiltration. RNA sequencing showed that CCR2/5i partially inhibited RT-induced TLR2/4 and RAGE signaling, leading to decreased expression of immunosuppressive cytokines including CCL2/CCL5, but increased expression of effector T cell chemokines such as CCL17/CCL22. This study thus supports the clinical development of CCR2/5i in combination with RT and ICIs for PDAC treatment.
Analysis of the inverse Born series: an approach through geometric function theory
Authors: Hoskins Jeremy G , Schotland John C
Published: April 2022

We analyze the convergence and approximation error of the inverse Born series, obtaining results that hold under qualitatively weaker conditions than previously known. Our approach makes use of tools from geometric function theory in Banach spaces. An application to the inverse scattering problem with diffuse waves is described.
Emission enhancement of femtosecond laser-induced breakdown spectroscopy using vortex beam
Authors: Wang Qiuyun , Dang Weijie , Jiang Yuanfei , Chen Anmin , Jin Mingxing
Published: April 2022

This paper used femtosecond Gaussian and vortex beams to ablate a Cu target and generate Cu plasmas. A Gaussian beam pulse is shaped into a vortex beam by a vortex wave plate (topological charge m = 1). The spectral intensity of Cu plasmas produced by the two lasers was measured, finding that the spectra with vortex beam were stronger than that with Gaussian beam. The spectral intensity was doubled by simply changing the Gaussian beam into the vortex beam. In addition, the position for maximum Cu atomic line emission along with the laser path was closer to the position of focusing-lens with increasing laser energy. Finally, the Boltzmann plot calculated the plasma temperature, finding that the plasma temperature with the vortex beam was also higher than that with the Gaussian beam. The results indicated that vortex beams could improve the spectral intensity of the femtosecond laser-induced plasmas.
Kohn anomalies in topological insulator thin films: first-principles study
Authors: Ghim Minjae , Jhi Seung-Hoon
Published: April 2022

Kohn anomaly is a non-smooth phonon softening induced by electron–phonon coupling in low-dimensional metals. Some measurements claimed that Kohn anomalies are present in topological materials due to the Dirac fermions in the bulk or in the surface. However, first-principles calculations have not reproduced the Kohn anomalies, especially, on the surface of topological insulators. It is still unclear about the origin of the controversy for the existence of the Kohn anomaly whether it is a numerical shortcoming or misinterpretation in measurement. In this study, we investigate the surface Kohn anomaly in two topological insulators Bi2Se3 and SnSe using the state-of-the-art Wannier interpolation schemes. We find that Bi2Se3 exhibits the Kohn anomaly but only in the bulk-like phonon modes by structural confinement along the c-axis. Interestingly, SnSe exhibits the surface Kohn anomaly in support of the experimental report on Pb0.7Sn0.3Se. We show that double Dirac cones in SnSe surface states are responsible for the Kohn anomaly, which is even enhanced if the subsurface states are partially occupied.
Real-time identification of performance degradation stages of rolling element bearings by RVCFI
Authors: Meng Jiadong , Yan Changfeng , Wen Tao , Wang Zonggang , Chen Guangyi , Wu Lixiao
Published: April 2022

The rolling element bearing is a critical component, and its fault results in most of the faults in rotary machines. The performance condition monitoring of bearings can improve the safety of equipment and can provide a reasonable maintenance plan at the optimal time. To identify the initial fault time (IFT) and performance degradation stages of a bearing based on the sampling signal from the start to the current time in real time, the monitoring indicator of the initial fault (MIIF) and the monitoring indicator of the degradation stages (MIDS) are constructed. Firstly, multiple features with stable and high robustness are calculated based on the envelope spectrum of the vibration signal. And these features are standardized and integrated by the weighted-sum of multiple standardized features into a fused indicator. Then, the online variation coefficient of the fused indicator and its rate are calculated. Finally, the MIIF and MIDS can be obtained using the variation coefficient and cumulative sum based on the rate of the variation coefficient of the fused indicator, respectively. Meanwhile, the adaptivity and versatility of the multi-resolution singular value decomposition algorithm are also improved. The proposed methods are verified using two public tested data packets. It is shown from the results that the methods are able to efficiently identify the IFT and performance degradation stages of a bearing in a timely manner.
Lightweight edge-attention network for surface-defect detection of rubber seal rings
Authors: Huang Ziyi , Hu Haijun , Shen Zhiyuan , Zhang Yu , Zhang Xiaowu
Published: April 2022

Detection of surface defects is an essential step to ensure the quality and reliability of rubber seal-ring products. Machine vision inspection methods have received attention from engineers because they are beneficial in terms of the detection speed or detection accuracy. It is important to simultaneously guarantee high speed and high accuracy of defect detection in practice production. Considering this problem, in this paper, we propose a YOLO-based (You Only Look Once) lightweight neural network with edge-attention fusion for defect detection of rubber rings. First, an edge-attention block is integrated into the network to improve the detection accuracy. The edge images are weighted with attention weights and summarized with feature maps in the block. Second, an involution-based feature pyramid structure is proposed to reduce the network size and computational cost by using a new involution operator, instead of a convolution operator, at the bottleneck of the feature pyramid. Comparison of the proposed network with popular YOLO networks was performed based on a rubber-ring-image dataset with 138 images. The network achieved the highest detection accuracy and fastest speed among selected lightweight networks, including YOLOv3-tiny, YOLOv5-s, and YOLOX-s. Moreover, compared with the large and highly accurate YOLOv3-spp network, the network size decreased by 93.45% and the computational cost decreased by 91.46%, while average precision only decreased by 3.41%. It can be concluded that the YOLO-based lightweight neural network reaches a good balance between detection speed and detection accuracy.
A novel 3-DoF piezoelectric robotic pectoral fin: design, simulation, and experimental investigation
Authors: Liu Rui , Wang Liang , Jin Jiamei , Zhao Heng , Zhang Anti , Chen Di
Published: April 2022

The fish pectoral fins, which play a vital role for fish swimming mobility, can perform three degree-of-freedom movements (rowing, feathering, and flapping motions), promoting that a lot of bionic robotic pectoral fins have been proposed and developed. However, these developed robotic pectoral fins driven by electromagnetic motors or smart materials still cannot fully realize the aforementioned three movement modes. To solve this problem, a novel piezoelectric robotic pectoral fin based on the converse piezoelectric effect and friction drive principle is proposed in this study, to achieve the three motion modes. Using a piezoelectric actuator, the robotic pectoral fin can be driven to move with three degree-of-freedom motion modes. Firstly, the overall structures of the proposed piezoelectric robotic pectoral fin and the designed piezoelectric actuator are explained in detailed. Additionally, a finite element simulation and a combination of vibration measurement and impedance analysis experiments are carried out to verify the effectiveness of the proposed piezoelectric actuator. Finally, an experimental investigation is conducted to evaluate output performances of the robotic pectoral fin prototype. Experimental results indicated that (a) the maximum average velocities of the rowing and flapping motions of the pectoral fin prototype under an excitation voltage of 550 Vpp are 290 and 241.7 deg s−1, respectively, and the maximum rotation speed of the feathering motion is 6.03 deg s−1; (b) the maximum output forces of the rowing and flapping motions of the pectoral fin are 2.156 and 2.107 N, respectively; (c) rowing motion start stop response times are 13 and 10.6 ms, flapping motion start and stop response times are 14.2 and 9.2 ms, and feathering motion start/stop response times are 34 and 56.8 ms, respectively.
Production of strange hadrons in jets and underlying events in pp and p–Pb collisions with ALICE
Authors: Cui Pengyao
Published: April 2022

The production of strange (

K

S

0

, Λ) and multi-strange (Ξ± and Ω±) hadrons in jets and underlying events in pp and p–Pb collisions is studied with ALICE at the LHC. Transverse momentum (p
T) differential density distribution of particles produced in a jet is compared to that of inclusive particle production and that in underlying events. The particle yield ratios of

(
Λ
+

Λ

¯

)

/

2

K

S

0

and

(

Ξ

−

+

Ξ

¯

+

)

/

(
Λ
+

Λ

¯

)

as a function of p
T are also investigated in jets and underlying events. The production of the multi-strange hadrons, Ξ± and Ω±, and the corresponding ratio in jets and underlying events are measured for the first time. The p
T-differential density distribution of hadrons associated with hard scattering decreases slower than that for inclusive production. The baryon-to-meson and baryon-to-baryon ratios measured in jets exhibit clear differences from values obtained from the inclusive spectra in the intermediate p
T range. The p
T distribution of strange hadrons produced in jets is also studied in pp collisions at

s

=
13

TeV

and

s

=
7

TeV

and in p–Pb collisions at

s

NN

=
5.02

TeV

. The p
T spectra of particle produced in jets are independent of collision systems and collision energies. No apparent collision energy and collision system dependence is observed for the particle yield ratios of

(
Λ
+

Λ

¯

)

/

2

K

S

0

and

(

Ξ

−

+

Ξ

¯

+

)

/

(
Λ
+

Λ

¯

)

associated with energetic jets. These new results are compared to PYTHIA 8 event generator. The

(
Λ
+

Λ

¯

)

/

2

K

S

0

ratio are generally reproduced by the model, but large discrepancies between data and PYTHIA simulations are observed for

(

Ξ

−

+

Ξ

¯

+

)

/

(
Λ
+

Λ

¯

)

.
Polynomial α-attractors
Authors: Kallosh Renata , Linde Andrei
Published: April 2022

Inflationary α-attractor models can be naturally implemented in supergravity with hyperbolic geometry. They have stable predictions for observables, such as ns
= 1 - 2/Ne
, assuming that the potential in terms of the original geometric variables, as well as its derivatives, are not singular at the boundary of the hyperbolic disk, or half-plane. In these models, the potential in the canonically normalized inflaton field φ has a plateau, which is approached exponentially fast at large φ. We call them exponential α-attractors. We present a closely related class of models, where the potential is not singular, but its derivative is singular at the boundary. The resulting inflaton potential is also a plateau potential, but it approaches the plateau polynomially. We call them polynomial α-attractors. Predictions of these two families of attractors completely cover the sweet spot of the Planck/BICEP/Keck data. The exponential ones are on the left, the polynomial are on the right.
Modulation instability analysis of Rossby waves based on (2 + 1)-dimensional high-order Schrödinger equation
Authors: Wang Cong , Li Jingjing , Yang Hongwei
Published: April 2022

Modulational instability is an important area of research with important practical and theoretical significance in fluid mechanics, optics, plasma physics, and military and communication engineering. In this paper, using multiscale analysis and a perturbation expansion method, starting from the quasi-geostrophic potential vortex equation, a new (2 + 1)-dimensional high-order nonlinear Schrödinger equation describing Rossby waves in stratified fluids is obtained. Based on this equation, conditions for the occurrence of modulational instability of Rossby waves are analyzed. Moreover, the effects of factors such as the dimension and order of the equation and the latitude at which Rossby waves occur on modulational instability are discussed. It is found that the (2 + 1)-dimensional equation provides a good description of the modulational instability of Rossby waves on a plane. The high-order terms affect the modulational instability, and it is found that instability is more likely to occur at high latitudes.
Firing activities in a fractional-order Hindmarsh–Rose neuron with multistable memristor as autapse
Authors: Li Zhi-Jun , Xie Wen-Qiang , Zeng Jin-Fang , Zeng Yi-Cheng
Published: April 2022

Considering the fact that memristors have the characteristics similar to biological synapses, a fractional-order multistable memristor is proposed in this paper. It is verified that the fractional-order memristor has multiple local active regions and multiple stable hysteresis loops, and the influence of fractional-order on its nonvolatility is also revealed. Then by considering the fractional-order memristor as an autapse of Hindmarsh–Rose (HR) neuron model, a fractional-order memristive neuron model is developed. The effects of the initial value, external excitation current, coupling strength and fractional-order on the firing behavior are discussed by time series, phase diagram, Lyapunov exponent and inter spike interval (ISI) bifurcation diagram. Three coexisting firing patterns, including irregular asymptotically periodic (A-periodic) bursting, A-periodic bursting and chaotic bursting, dependent on the memristor initial values, are observed. It is also revealed that the fractional-order can not only induce the transition of firing patterns, but also change the firing frequency of the neuron. Finally, a neuron circuit with variable fractional-order is designed to verify the numerical simulations.
Numerical methods to evaluate Koopman matrix from system equations*
Authors: Ohkubo Jun
Published: April 2022

The Koopman operator is beneficial for analyzing nonlinear and stochastic dynamics; it is linear but infinite-dimensional, and it governs the evolution of observables. The extended dynamic mode decomposition (EDMD) is one of the famous methods in the Koopman operator approach. The EDMD employs a data set of snapshot pairs and a specific dictionary to evaluate an approximation for the Koopman operator, i.e., the Koopman matrix. In this study, we focus on stochastic differential equations, and a method to obtain the Koopman matrix is proposed. The proposed method does not need any data set, which employs the original system equations to evaluate some of the targeted elements of the Koopman matrix. The proposed method comprises combinatorics, an approximation of the resolvent, and extrapolations. Comparisons with the EDMD are performed for a noisy van der Pol system. The proposed method yields reasonable results even in cases wherein the EDMD exhibits a slow convergence behavior.
Experimental investigation on the hydrogen embrittlement characteristics and mechanism of natural gas-hydrogen transportation pipeline steels
Authors: Cai Liuxi , Bai Guangqian , Gao Xiufeng , Li Yun , Hou Yanfang
Published: April 2022

Hydrogen blended with natural gas is one of the best ways for large-scale hydrogen transportation; however, pipeline steels exploited for transferring natural gas have the risk of hydrogen embrittlement. Therefore, the hydrogen damage mechanism and resistance property of different steel pipelines should be carefully examined to select suitable materials for the task mentioned above. The common X42, X52, X70, and AISI 1020 are taken into account as research objects. Their mechanical properties and hydrogen absorption properties in a hydrogen environment are investigated to explore further factors affecting the hydrogen embrittlement of material. Dynamic slow strain rate tensile test results show that these materials exhibit varying hydrogen embrittlement sensitivity in a hydrogen environment. AISI 1020 has the highest hydrogen embrittlement susceptibility, then X70, and X42 presents the lowest one. Generally, hydrogen embrittlement behaviours are strengthened by increasing the current density. As the current density grows, the fracture mode of pipeline steels transforms from the ductile fracture to the quasi-cleavage fracture and finally turns into the cleavage fracture. The hydrogen embrittlement fracture of the tensile specimen results from the action of the HEDE and HELP in various zones. TDS test results indicates that the content of C and Mn significantly influence on the hydrogen solubility in metal materials.
Thiazide and the Thiazide-Like Diuretics: Review of Hydrochlorothiazide, Chlorthalidone, and Indapamide
Authors: Ernst Michael E , Fravel Michelle A
Published: April 2022

The term thiazide is universally understood to refer to diuretics that exert their principal action in the distal tubule. The thiazide class is heterogenous and can be further subdivided into compounds containing the benzothiadiazine ring structure—the thiazide-type (e.g., hydrochlorothiazide)—and those lacking the benzothiadiazine ring—the thiazide-like (e.g., chlorthalidone and indapamide) drugs. Thiazide-like agents are longer acting and constitute the diuretics used in most of the cardiovascular outcome trials that established benefits of treatment with diuretics, but pragmatic aspects, such as lack of availability in convenient formulations, limit their use. Regardless of class heterogeneity, thiazides have retained importance in the management of hypertension for over 60 years. They are reliably effective as monotherapy in a majority of hypertensive patients, and augment the efficacy of other classes of antihypertensives when used in combination. Importantly, a thiazide-based treatment regimen lowers cardiovascular events, and their sturdy effect reinforces their place among the recommended first-line agents to treat hypertension in major domestic and international hypertension guidelines. There are few head-to-head comparisons within the class, but potential differences have been explored indirectly as well as in non-blood pressure mechanisms and potential pleiotropic properties. Until proven otherwise, the importance of these differences remains speculative, and clinicians should assume that cardiovascular events will be lowered similarly across agents when equivalent blood pressure reduction occurs. Thiazides remain underutilized, with only about one-third of hypertensive patients receiving them. For many patients, however, a thiazide is an indispensable component of their regimen to achieve adequate blood pressure control.
Clinical Practice Changes in Monitoring Hypertension Early in the COVID-19 Pandemic
Authors: Robbins Cheryl L , Ford Nicole D , Hayes Donald K , Ko Jean Y , Kuklina Elena , Cox Shanna , Ferre Cynthia , Loustalot Fleetwood
Published: April 2022

Background

Clinical practices can use telemedicine and other strategies (e.g., self-measured blood pressure [SMBP]) for remote monitoring of hypertension to promote control while decreasing risk of exposure to SARS-CoV-2, the virus that causes COVID-19.

Methods

The DocStyles survey collected data from primary care providers (PCPs), obstetricians-gynecologists (OB/GYNs), and nurse practitioners/physician assistants (NP/PAs) in fall 2020 (n = 1,502). We investigated clinical practice changes for monitoring hypertension that were implemented early in the COVID-19 pandemic and examined differences by clinician and practice characteristics (P < 0.05).

Results

Overall, 369 (24.6%) of clinicians reported their clinical practices made no changes in monitoring hypertension early in the pandemic, 884 (58.9%) advised patients to monitor blood pressure at home or a pharmacy, 699 (46.5%) implemented or increased use of telemedicine for blood pressure monitoring visits, and 545 (36.3%) reduced the frequency of office visits for blood pressure monitoring. Compared with NP/PAs, PCPs were more likely to advise SMBP monitoring (adjusted prevalence ratios [aPR] 1.28, 95% confidence intervals [CI] 1.11–1.47), implement or increase use of telemedicine (aPR 1.23, 95% CI 1.04–1.46), and reduce the frequency of office visits (aPR 1.37, 95% CI 1.11–1.70) for blood pressure monitoring, and less likely to report making no practice changes (aPR 0.63, 95% CI 0.51–0.77).

Conclusions

We noted variation in clinical practice changes by clinician type and practice characteristics. Clinical practices may need additional support and resources to fully maximize telemedicine and other strategies for remote monitoring of hypertension during pandemics and other emergencies that can disrupt routine health care.
Practice Advisory on Gluteal Fat Grafting
Authors: Del Vecchio Daniel , Kenkel Jeffrey M
Published: April 2022

On January 31, 2018, The Multi-Society Task Force for Safety in Gluteal Fat Grafting released a practice advisory regarding gluteal fat grafting. The task force was assembled in the wake of several highly publicized patient deaths involving Brazilian Butt Lift (BBL) and produced a second practice advisory in August 2019. In 2021, The Aesthetic Surgery President commissioned a Working Group on BBL Patient Safety, charging the group to address new guidelines affecting safety and welfare of BBL patients. The “Practice Advisory on Gluteal Fat Grafting” is the first advisory developed since the working group was formed. In addition to surgical technique as a major cause of fatal complications of BBL, the working group focused on micro-economic trends of operative time and regional BBL pricing and considered fatigue and distraction in formulating the current guidelines. In Florida, the majority of BBL deaths occur at the end of the week. Such a non-normalized distribution most likely represents the result of fatigue and/or distraction, which has been linked to surgical mortality in multiple published communications. In addition, mortality is likely due to uncertainty or lack of documentation as to the correct plane of fat injection. Therefore, the newest and most compelling recommendations from these guidelines include the utilization of ultrasound-guided documentation of cannula placement prior to and during fat injection, and the limitation of 3 BBL cases as a maximum amount of total operative cases per day. The authors thank members of the task force for the insights they brought to this process.

Level of Evidence: 4
Dietary scallop oil prepared from the internal organs of Japanese giant scallop (Patinopecten yessoensis) improved mite allergen-induced atopic dermatitis-like symptoms on the dorsal skin of NC/Nga mice
Authors: Sugimoto Koki , Hagihara Nozomi , Hosomi Ryota , Yoshida Munehiro , Fukunaga Kenji
Published: April 2022

This study aimed to investigate the effects of scallop oil (SCO) on atopic dermatitis (AD)-like symptoms induced by mite allergens in the dorsal and ear skins of NC/Nga mice compared to those of refined corn oil and krill oil (KO). SCO, rich in n-3 polyunsaturated fatty acids and phospholipids, was prepared from the internal organs of Japanese giant scallop, an underutilized fishery resource in Japan. Results showed that SCO intake improved AD-like symptoms, including ear edema, ear thickness, and transepidermal water loss of dorsal skin, and tended to decrease the scratching behavior, whereas KO intake did not. Further, SCO intake decreased the degranulated mast cell count and increased the tight junction protein claudin-1 expression, which is important for the barrier function, in the dorsal skin compared to refined corn oil intake. SCO improved the AD-like symptoms by suppressing mast cell degranulation and strengthening the barrier function of dorsal skin in NC/Nga mice.
Activin A promotes hyaluronan production and upregulates versican expression in human granulosa cells
Authors: Tian Shen , Zhang Han , Chang Hsun-Ming , Klausen Christian , Huang He-Feng , Jin Min , Leung Peter C K
Published: April 2022

Hyaluronan is a structural component of the expanded cumulus matrix, and hyaluronan synthase 2 is the major enzyme for the synthesis of hyaluronan in humans. Versican cross-links the hyaluronan-rich matrix to cumulus cells and is critical for successful ovulation. Activin A is a critical intrafollicular regulator of ovarian function. Although activin A has been shown to promote cumulus matrix expansion in mice, the functional role of activin A in the regulation of cumulus expansion in the human ovary remains to be elucidated. Using primary and immortalized human granulosa-lutein cells as study models, we provide the first data showing that activin A increased the production of hyaluronan by upregulating the expression of hyaluronan synthase 2 in these cells. Additionally, activin A also promoted the expression of the hyaluronan-binding protein versican. Moreover, using inhibitor- and small interfering RNA-mediated inhibition approaches, we found that these stimulatory effects of activin A are most likely mediated through the type I receptor activin receptor-like kinase (ALK4)-mediated Sma- and Mad-related protein (SMAD2)/SMAD3-SMAD4 signaling pathway. Notably, the chromatin immunoprecipitation analyses demonstrated that SMAD4 could bind to human hyaluronan synthase 2 and VERSICAN promoters. The results obtained from this in vitro study suggest that locally produced activin A plays a functional role in the regulation of hyaluronan production and stabilization in human granulosa-lutein cells.
Distinct developmental phenotypes result from mutation of Set8/KMT5A and histone H4 lysine 20 inDrosophila melanogaster
Authors: Crain Aaron T , Klusza Stephen , Armstrong Robin L , Santa Rosa Priscila , Temple Brenda R S , Strahl Brian D , McKay Daniel J , Matera A Gregory , Duronio Robert J
Published: April 2022

Mono-methylation of histone H4 lysine 20 (H4K20me1) is catalyzed by Set8/KMT5A and regulates numerous aspects of genome organization and function. Loss-of-function mutations in Drosophila melanogaster Set8 or mammalian KMT5A prevent H4K20me1 and disrupt development. Set8/KMT5A also has non-histone substrates, making it difficult to determine which developmental functions of Set8/KMT5A are attributable to H4K20me1 and which to other substrates or to non-catalytic roles. Here, we show that human KMT5A can functionally substitute for Set8 during Drosophila development and that the catalytic SET domains of the two enzymes are fully interchangeable. We also uncovered a role in eye development for the N-terminal domain of Set8 that cannot be complemented by human KMT5A. Whereas Set820/20 null mutants are inviable, we found that an R634G mutation in Set8 predicted from in vitro experiments to ablate catalytic activity resulted in viable adults. Additionally, Set8(R634G) mutants retain significant, albeit reduced, H4K20me1, indicating that the R634G mutation does not eliminate catalytic activity in vivo and is functionally hypomorphic rather than null. Flies engineered to express only unmodifiable H4 histones (H4K20A) can also complete development, but are phenotypically distinct from H4K20R, Set820/20 null, and Set8R634G mutants. Taken together, our results demonstrate functional conservation of KMT5A and Set8 enzymes, as well as distinct roles for Set8 and H4K20me1 in Drosophila development.
Supplementation of live yeast culture modulates intestinal health, immune responses, and microbiota diversity in broiler chickens
Authors: Kim Eunjoo , Kyoung Hyunjin , Hyung Koh Nae , Lee Hanbae , Lee Seonmin , Kim Yonghee , Il Park Kyeong , Min Heo Jung , Song Minho
Published: April 2022

The present study investigated the effects of live yeast cultures (LYC) on growth performance, gut health indicators, and immune responses in broiler chickens. A total of 720 mixed-sex broilers (40 birds/pen; 9 replicates/treatment) were randomly allocated to two dietary treatments: (1) a basal diet based on corn–soybean meal (CON) and (2) CON with 1 g/kg LYC. At 35 d of age, one bird per replicate pen was chosen for biopsy. LYC group tended (P < 0.10) to increase average daily gain during the grower phase compared with CON group. Broilers fed LYC diet had increased (P = 0.046) duodenal villus height and area but reduced (P = 0.003) duodenal crypt depth compared with those fed CON diet. Birds fed LYC diet presented alleviated (P < 0.05) serum TNF-α, IL-1β, and IL-6 levels compared with those fed CON diet. Further, birds fed LYC diet exhibited upregulated (P < 0.05) ileal tight junction-related proteins and pro-inflammatory cytokines in the ileal tissue compared with those fed CON diet. Inverse Simpson’s diversity (P = 0.038) revealed that birds fed CON diet had a more diverse microbiota community in the ileal digesta, compared with those fed LYC diet, while no significant difference between the treatments on Chao1 and Shannon’s indices was observed. Based on the weighted UniFrac distance, the PCoA showed that microbiota in the ileal digesta of the LYC group was different from that of the CON group. LYC group increased the abundance of the phyla Firmicutes and genera Lactobacillus, Prevotella, and Enterococcus compared with CON group. The present study demonstrated that supplemental LYC as a feed additive provide supportive effects on enhancing gut functionality by improving the upper intestinal morphology and gut integrity, and modulating the immune system and microbiota communities of birds.