bluuebunny/crossref_metadata_2025 huggingface dataset:
Auswirkungen der Belegungsdichte in Ferkelbuchten
Authors: Ganz Sebastian
Published: April 2020

Laskoski F, Faccin JEG, Vier CM et al. Effects of pigs per feeder hole and group size on feed intake onset, growth performance, and ear and tail lession in nursery pigs with consistent space allowance. J Swine Health Prod 2019; 27 (1): 12–18

Eine herabgesetzte Futteraufnahme nach dem Absetzen und damit verbundene niedrigere Tageszunahmen können sich negativ auf die Leistung und den Metabolismus eines Schweines auswirken. Der Einfluss der Belegungsdichte in Ferkelbuchten in dieser Zeit auf Tageszunahme, Beginn der Futteraufnahme nach dem Absetzen und Inzidenz von Verletzungen der Ohren und Schwänze ist wenig untersucht. Studien zufolge kann eine hohe Belegungsdichte und ein damit verbundener Platzmangel am Futterautomat negative Auswirkungen nach dem Absetzen haben. Es verringern sich nicht nur die Werte der Leistungsparameter wie tägliche Zunahmen, sondern es steigt auch die interindividuelle Aggression, was sich in vermehrtem Beißen oder Kämpfen zwischen den Tieren einer Gruppe äußert. In dieser Studie wurden die Zusammenhänge zwischen Belegungsdichte und Platz an der Futterstelle auf Wachstumsrate, Beginn der Futteraufnahme nach dem Absetzen und Auftreten von Läsionen an Ohren und Schwänzen untersucht.
Der Verlauf des E-Zigarettenkonsums im Jugendalter: Eine Kohortenstudie über 18 Monate
Authors: Hanewinkel R. , Isensee B. , Seidel A.-K. , Goecke M. , Morgenstern M.
Published: April 2020

Ziel Deskription des E-Zigarettenkonsums Jugendlicher über die Zeit.

Methode 261 Jugendliche aus Nordrhein-Westfalen, die E-Zigaretten mindestens einmal monatlich konsumiert hatten (mittleres Alter: 14,9 Jahre; 33,5 % weiblich), nahmen 2017 und 2019 an einer Fragebogenstudie teil.

Ergebnisse 2017 berichteten 84 Jugendliche (32,2 %) ausschließlichen E-Zigarettenkonsum (Single User), 177 Jugendliche wurden als Dual User eingestuft (67,8 %), da sie zusätzlich zur E-Zigarette ein Tabakprodukt (konventionelle Zigarette und/oder Shisha) konsumierten. Im Beobachtungs­zeitraum von 18 Monaten stellten insgesamt 83 Jugendliche (31,8 %) den Konsum von Nikotinprodukten ein. Dual User stellten den Nikotinkonsum seltener ein als Single User (N = 39 bzw. 22,0 % vs. N = 44 bzw. 52,4 %, p < 0,001). 7 Single User (8,3 %) veränderten ihr Verhalten nicht, 11 begannen ausschließlich Tabak zu konsumieren (13,1 %), weitere 22 (26,2 %) wechselten zum Dual Use. 78 Dual User (44,1 %) veränderten ihr Verhalten nicht, 57 (32,1 %) wechselten zum ausschließlichen Tabakkonsum, 3 (1,7 %) konsumierten ausschließ­lich E-Zigaretten. Zusammengenommen nutzten von den verbliebenen 178 konsumierenden Jugendlichen am Ende der Studie 10 (5,6 %) ausschließlich E-Zigaretten, während 168 (94,4 %) Tabak rauchten oder Dual Use betrieben.

Schlussfolgerungen Mehr als zwei Drittel aller jugendlichen E-Zigarettenkonsumenten und über drei Viertel der Dual User konsumierte auch 18 Monate später Nikotinprodukte. Unter den verblieben Konsumenten zeigte sich ein seltenerer Verbleib oder Umstieg auf den Single Use, statt­dessen ein häufigerer reiner Tabakkonsum oder Dual Use.
Quantitative Assessment of Fatty Liver using Ultrasound with Normalized Local Variance Technique
Authors: Bae Jae Seok , Lee Dong Ho , Lee Jae Young , Kim Haeryoung , Yu Su Jong , Lee Jeong-Hoon , Cho Eun Ju , Lee Yun Bin , Han Joon Koo , Choi Byung Ihn
Published: April 2020

Purpose To assess the diagnostic performance of the normalized local variance (NLV) ultrasound technique in the detection of the fatty liver using histopathology as a reference standard.

Materials and Methods We prospectively enrolled 194 consecutive patients with clinical suspicion of diffuse liver disease or history of liver transplantation. Conventional grayscale ultrasound and NLV examinations were performed and immediately followed by liver biopsies. The degrees of fatty liver, necroinflammatory activity, and fibrosis stage were evaluated by histopathological assessment. The diagnostic performance of the NLV values in detecting each grade of fatty liver was determined using receiver operating characteristics analyses, and multivariate linear regression analyses were performed to identify variables significantly associated with the NLV values.

Results The number of patients in each degree of fatty liver and hepatic fibrosis was 118/37/26/13 and 81/68/24/6/14 for none/mild/moderate/severe steatosis and F0 / F1/F2 / F3/F4 fibrosis on histopathological examinations, respectively. The area under the receiver operating characteristics curve and optimal cut-off NLV value for detecting fatty liver of varying degrees were 0.911 and 1.095 for ≥ S1, 0.974 and 1.055 for ≥ S2, and 0.954 and 1.025 for ≥ S3, respectively. Multivariate analyses revealed that not fibrosis or inflammation but rather the degree of steatosis was associated with the NLV value.

Conclusion The NLV value demonstrated excellent diagnostic performance for detecting varying degrees of fatty liver, and the degree of steatosis on histopathological examinations was the only significant factor affecting the NLV value.
Renin-Angiotensin-System (RAS) und COVID-19 – Zur Verordnung von RAS-Blockern
Authors: Kreutz Reinhold , Abd El-Hady Algharably Engi , Ganten Detlev , Messerli Franz
Published: April 2020

Twenty years ago, an enzyme homologous to the previously known angiotensin-converting enzyme (ACE) was identified, and subsequently named ACE2. In the renin-angiotensin system (RAS), ACE2 has counter-regulatory functions against the classical effector peptide angiotensin II, for example in blood pressure regulation and cardiovascular remodeling. However, ACE2 provides an initially unexpected interesting link between virology and cardiovascular medicine. That is, ACE2 represents the binding receptor for the cellular uptake of SARS-CoV and SARS-CoV-2 viruses. Thus, ACE2 is relevant for COVID-19. In this context, it was suspected that therapy with RAS blockers might promote transmission and complications of COVID-19 by upregulation of ACE2 expression. The aim of this short review is, to describe the link between the RAS, particularly ACE2, and COVID-19. Based on our analysis and evaluation of the available findings, we justify our conclusion: important drugs such as ACE inhibitors and angiotensin receptor blockers should continue to be prescribed according to guidelines to stable patients in the context of the COVID-19 pandemic.
Aplicação do protocolo Ottawa por estudantes de medicina e residentes de ortopedia em entorses de tornozelo em um hospital de trauma
Authors: Lavrador Filho José Marcos , Vogt Paulo Henrique , Coelho Alexandre Roberto Roman , Cho Daniel Kyubin , da Silva João Luiz Vieira , Padoani Patrick Willian
Published: April 2020

Objetivo Verificar a aplicabilidade e a concordância das regras do tornozelo de Ottawa aplicadas por estudantes de medicina e residentes de ortopedia em um serviço de trauma terciário, validando assim as regras de Ottawa para utilização em solo brasileiro.

Método Estudo prospectivo, realizado em um hospital terciário, incluindo todos os pacientes com trauma torcional agudo da articulação tibiotársica. Os pacientes realizaram radiografias de tornozelo e/ou pé, tendo sido aplicado o questionário com as regras do tornozelo de Ottawa por acadêmicos e, na sequência, por residentes. As radiografias foram avaliadas por ortopedistas plantonistas e especialista em pé e tornozelo, sendo a opinião do especialista considerada padrão-ouro da análise.

Resultados Foram avaliados 263 pacientes e, após aplicados os critérios de inclusão estabelecidos, restaram para a avaliação 226 casos. A sensibilidade para detectar lesões e o valor preditivo negativo (VPN) foi de 100%. O teste mais sensível e com maior VPN para ambos, acadêmicos e residentes, foi a palpação do maléolo lateral. O estudo apresentou potencial de redução de 30% no total de exames solicitados.

Conclusão Os dados demostraram aplicabilidade e concordância entre acadêmicos e residentes, o que permite a validação do protocolo de Ottawa nos atendimentos de urgência e emergência no Brasil.
Laparoscopic Dismembered Repair in Two Patients with Retrocaval Ureter
Authors: Cavaleri Yuri , Farullo Giuseppe , Nappo Simona Gerocarni , Caione Paolo
Published: April 2020

Retrocaval ureter (RCU) or circumcaval ureter is a rare cause of congenital hydronephrosis. The surgical correction of RCU should be performed in all patients with obstruction and hydronephrosis symptoms, lumbar pain, urinary tract infections, hematuria, or urolithiasis. Traditionally, an open surgical approach was used for the treatment of RCU. Nowadays, surgical correction of these anomalies is performed using minimally invasive techniques. We report on two cases treated with our standardized laparoscopic technique using only three 5-mm trocars. The proposed approach could be considered as the first-line treatment for RCU.
Transpedal Approach in Failed Antegrade Attempt of Lower Limb Peripheral Arterial Disease—A Review with Different Treatment Strategies
Authors: Nath Ranjit Kumar , Subramaniyan Siva , Pandit Neeraj , Vatsa Deepankar
Published: April 2020

Transpedal access is an evolving technique primarily used in patients after failed femoral antegrade approach to revascularize complex tibiopedal lesions. In patients who are at high risk for surgery the transpedal access may be the only option in failed antegrade femoral access to avoid amputation of the limbs. In recent years transpedal access is used routinely to revascularize supra-popliteal lesions due to more success and less complications over femoral artery approach. Retrograde approach parse will not give success in all cases and importantly success depends on techniques used. There are different techniques that need to be used depending on lesion characteristics, comorbidities, and hardware available to improve success with less complications. This review provides different strategies for successful treatment of iliac and femoral artery lesions by transpedal approach after failed antegrade femoral attempt.
Hepatitis C Virus in Pregnancy: A Systematic Review of the Literature
Authors: Andes Alexandra , Ellenberg Kerry , Vakos Amanda , Collins James , Fryer Kimberly
Published: April 2020

Objective The aim of this study was to systematically review the literature to summarize recent demographic characteristics of hepatitis C virus (HCV) infection during pregnancy and the efficacy of risk-based versus universal screening.

Study Design PubMed, EMBASE, and Cochrane Library were searched to identify relevant studies. Studies that recognized hepatitis C as a primary or secondary outcome, with pregnant women as the population and written in English, were included. Studies were excluded if they were abstracts only, written in foreign language, or published prior to 1992. Two researchers independently screened all the studies by titles, abstracts, and full text. Conflicts were settled by a third researcher.

Results A total of 698 studies were identified with 78 fitting inclusion criteria. In total, 69 epidemiologic and 9 comparison studies were found. Identified risk factors for HCV infection include intravenous or illicit drug use, sexually transmitted coinfection, high-risk behaviors in the partners, high parity, and history of miscarriages or abortions. Demographic characteristics associated with HCV include non-Hispanic white race, American Indian or Alaskan Native ethnicity, and increasing age. Providers may fail to adequately screen for each risk factor, and up to two-thirds of women with a known risk factor are not screened under current guidelines. Finally, up to 27% of HCV+ women have no identifiable risk factors for infection.

Conclusion There is evidence that risk-based screening fails to identify a large proportion of HCV positive women in pregnancy and that pregnant women with HCV risk factors and consistent with current screening guidelines fail to be tested. We urge for the adoption of universal screening to identify these women and offer treatment.
Klinikeinkäufer noch besser qualifizieren: Weiterbildungen: ein zentrales Element zur Mitarbeiterbindung und -entwicklung
Authors: Dolderer Sophia
Published: April 2020

Für den Erfolg jedes Unternehmens sind gute Mitarbeiter ausschlaggebend, jedoch ist es nicht immer einfach, diese Mitarbeiter zu finden und darüber hinaus auch zu halten. Neben einer guten Arbeitsinfrastruktur, dem Arbeitsklima, der Wertschätzung der erbrachten Arbeit sowie dem Gehalt und Urlaub tragen auch regelmäßige Fortbildungen zur Mitarbeiterbindung bei. Zusätzlich ermöglichen die Fortbildungen, die eigenen Mitarbeiter in ihren Fähigkeiten weiterzuentwickeln und so aus eigener Kraft dem um sich greifenden Fachkräftemangel entgegenzuwirken.
Machine learning for nonintrusive model order reduction of the parametric inviscid transonic flow past an airfoil
Authors: Renganathan S. Ashwin , Maulik Romit , Rao Vishwas
Published: April 2020

Fluid flow in the transonic regime finds relevance in aerospace engineering, particularly in the design of commercial air transportation vehicles. Computational fluid dynamics models of transonic flow for aerospace applications are computationally expensive to solve because of the high degrees of freedom as well as the coupled nature of the conservation laws. While these issues pose a bottleneck for the use of such models in aerospace design, computational costs can be significantly minimized by constructing special, structure-preserving surrogate models called reduced-order models. In this work, we propose a machine learning method to construct reduced-order models via deep neural networks and we demonstrate its ability to preserve accuracy with a significantly lower computational cost. In addition, our machine learning methodology is physics-informed and constrained through the utilization of an interpretable encoding by way of proper orthogonal decomposition. Application to the inviscid transonic flow past the RAE2822 airfoil under varying freestream Mach numbers and angles of attack, as well as airfoil shape parameters with a deforming mesh, shows that the proposed approach adapts to high-dimensional parameter variation well. Notably, the proposed framework precludes the knowledge of numerical operators utilized in the data generation phase, thereby demonstrating its potential utility in the fast exploration of design space for diverse engineering applications. Comparison against a projection-based nonintrusive model order reduction method demonstrates that the proposed approach produces comparable accuracy and yet is orders of magnitude computationally cheap to evaluate, despite being agnostic to the physics of the problem.
Vorticity transport in laminar steady rotating plumes
Authors: Martins F. C. , Pereira J. M. C. , Pereira J. C. F.
Published: April 2020

A steady laminar rotating thermal plume was investigated by the numerical solution of the 3D momentum and energy equations. The flow originated from a low momentum hot jet (Richardson number Ri = 173 and Grashof number Gr = 5000) issued from a small inlet in the bottom wall of a cylindrical domain with a permeable lateral surface that is rotating (Ekman number Ek = 12). Second order accurate calculations of the structure and dynamics of the buoyant vortex were investigated, with specific emphasis on the evolution of the vorticity distributions and their effects on the ensuing vortex. Budgets of the vorticity transport equations were investigated to analyze the genesis of the developed axial vorticity, explaining how the whirling flow was generated. Nonslip and slip bottom boundary conditions allowed the investigation of the impact of the boundary layer on the axial vorticity generation. The results showed that there is a conversion of radial vorticity into axial vorticity. The radial vorticity was found to be generated not only in the boundary layer but also by tilting of the tangential vorticity, which results from buoyancy. Additionally, the boundary layer was found to have a strong impact on the generation of axial vorticity, but not to be necessary to generate the whirl. In fact, a stronger whirl was originated without the effect of the boundary layer, since the axial vorticity was generated closer to the inlet, where additional stretching is provided by the acceleration of the flow.
Everything you always wanted to know about metallic hydrogen but were afraid to ask
Authors: Gregoryanz Eugene , Ji Cheng , Dalladay-Simpson Philip , Li Bing , Howie Ross T. , Mao Ho-Kwang
Published: April 2020

The hydrogen molecule is made from the first and lightest element in the periodic table. When hydrogen gas is either compressed or cooled, it forms the simplest molecular solid. This solid exhibits many interesting and fundamental physical phenomena. It is believed that if the density of the solid is increased by compressing it to very high pressures, hydrogen will transform into the lightest known metal with very unusual and fascinating properties, such as room temperature superconductivity and/or superfluidity. In this article, we provide a critical look at the numerous claims of hydrogen metallization and the current experimental state of affairs.
Dietary supplementation with avilamycin and Lactobacillus acidophilus effects growth performance and the expression of growth-related genes in broilers
Authors: Saleh A. A. , Amber K. , Mohammed A. A.
Published: April 2020

Context
The use of antibiotics in poultry production is appropriate; however, it brings a high risk of dissemination of antibiotic-resistant strains of pathogenic and non-pathogenic bacteria and their further transmission to humans via the food chain.

Aims
The effects of supplementation with Lactobacillus acidophilus (a probiotic) or avilamycin (an in-feed antibiotic growth promoter), on growth performance, digestibility, plasma lipid levels, and the expression of certain growth-related genes were investigated.

Methods
In total, 135 15-day-old broiler chicks were divided into three groups (n = 45): a control group and two treatment groups. Each treatment group was then further divided into three replicates (15 birds each). The control group was fed a basal diet; the second group received basal diet supplemented with avilamycin (0.1 g/kg); the third group received basal diet plus L. acidophilus (0.1 g/kg). Growth performance (bodyweight, feed intake and feed-conversion ratio) was measured. Digestibility and gene expression were measured at the end of the experiment.

Key results
Greatest bodyweight gain was achieved in the L. acidophilus-fed chicks, which were significantly (P < 0.05) heavier than the control chicks and the avilamycin-fed chicks. Addition of avilamycin or L. acidophilus to the diet also significantly improved feed efficiency (P < 0.05) compared with the control. Although the digestibility of dry matter, crude protein and crude fibre significantly improved in the two experimental groups compared with the control, ether extract was not affected. In addition, plasma total cholesterol, triglyceride and low-density-lipoprotein cholesterol levels were significantly (P < 0.05) decreased whereas plasma high-density-lipoprotein cholesterol was significantly (P < 0.05) increased in the L. acidophilus group compared with the control. Expression of the genes for growth hormone secretagogue receptor (GHSR), insulin-like growth factor 1 (IGF-1) and insulin-like growth factor 1 receptor (IGF1R) was remarkably upregulated in the skeletal muscles of the two experimental groups.

Conclusions
Supplementation with L. acidophilus (0.1 g/kg) in the broiler diet had positive effects on growth, feed intake, feed efficiency, digestibility, and plasma lipid levels of the broilers.

Implications
Lactobacillus acidophilus might be a more useful additive in broiler feed than antibiotic growth promoters such as avilamycin.
Analysis of the population dynamics of the endangered American crocodile, Crocodylus acutus in Paramillo National Natural Park
Authors: Ortega-León Angela María , Santos-Morales Amilcar H. , Zamora-Abrego Joan Gastón , Pérez-Mendoza Hibraim Adán
Published: April 2020

Few studies have been conducted on the population dynamics of crocodiles, especially in the Neotropics. This is the first study to provide data on the population dynamics of the threatened American crocodile (Crocodylus acutus (Cuvier, 1807)) in Paramillo National Natural Park. Twenty-four survey routes of 22km each were studied, and a total of 733 sightings was recorded. During the study period (from October 2014 to March 2016), the population remained stable and experienced slight growth (λ=1.049±0.428). Offspring production by the adults II stage was the most sensitive contribution (17.05), whereas the permanence of this adult stage was the demographic process that contributed the most to population growth (0.653). However, an 18% decrease in adults II would jeopardise long-term population viability and lead to a high probability of quasi-extinction, with under 300 individuals over the next 30 years. Thus, despite the apparent stability of this population, we suggest that it be considered a key target for future conservation efforts. Additionally, we recommend that this species continue to be listed as endangered in Colombia and not be modified in the CITES Appendix I.
Spread and dynamics of the COVID-19 epidemic in Italy: Effects of emergency containment measures
Authors: Gatto Marino , Bertuzzo Enrico , Mari Lorenzo , Miccoli Stefano , Carraro Luca , Casagrandi Renato , Rinaldo Andrea
Published: April 2020

Significance

The ongoing pandemic of COVID-19 challenges globalized societies. Scientific and technological cross-fertilization yields broad availability of georeferenced epidemiological data and of modeling tools that aid decisions on emergency management. To this end, spatially explicit models of the COVID-19 epidemic that include e.g. regional individual mobilities, the progression of social distancing, and local capacity of medical infrastructure provide significant information. Data-tailored spatial resolutions that model the disease spread geography can include details of interventions at the proper geographical scale. Based on them, it is possible to quantify the effect of local containment measures (like diachronic spatial maps of averted hospitalizations) and the assessment of the spatial and temporal planning of the needs of emergency measures and medical infrastructure as a major contingency planning aid.
Differential requirement for Bub1 and Bub3 in regulation of meiotic versus mitotic chromosome segregation
Authors: Cairo Gisela , MacKenzie Anne M. , Lacefield Soni
Published: April 2020

Accurate chromosome segregation depends on the proper attachment of kinetochores to spindle microtubules before anaphase onset. The Ipl1/Aurora B kinase corrects improper attachments by phosphorylating kinetochore components and so releasing aberrant kinetochore–microtubule interactions. The localization of Ipl1 to kinetochores in budding yeast depends upon multiple pathways, including the Bub1–Bub3 pathway. We show here that in meiosis, Bub3 is crucial for correction of attachment errors. Depletion of Bub3 results in reduced levels of kinetochore-localized Ipl1 and concomitant massive chromosome missegregation caused by incorrect chromosome–spindle attachments. Depletion of Bub3 also results in shorter metaphase I and metaphase II due to premature localization of protein phosphatase 1 (PP1) to kinetochores, which antagonizes Ipl1-mediated phosphorylation. We propose a new role for the Bub1–Bub3 pathway in maintaining the balance between kinetochore localization of Ipl1 and PP1, a balance that is essential for accurate meiotic chromosome segregation and timely anaphase onset.
‘Detektory Dla Szkół’: a pilot
detector-lending project for Polish schools
Authors: Deja Katarzyna , Adamowski Łukasz , Kirejczyk Marek , Marcinkowska-Sanner Maja , Gąsowska Martyna
Published: April 2020

This article presents the Polish project entitled ‘Detektory dla
Szkół’ (‘Detectors for Schools’, throughout the
paper referred to as ‘the programme’). It was developed at the
Education and Training Division of the National Centre for Nuclear Research
(Narodowe Centrum Badań Jądrowych, NCBJ) in Poland. The programme
allows the schools to borrow from NCBJ two types of radiation detectors:
Geiger–Müller counter and CosmicWatch detector(s). Student
participation in the measurements is expected.
Analysis of the C2

(

d

3

Π

g

−

a

3

Π

u

)

Swan bands as a thermometric probe in CO2 microwave plasmas
Authors: Carbone Emile , D’Isa Federico , Hecimovic Ante , Fantz Ursel
Published: April 2020

The optical emission spectra of high pressure CO2 microwave plasmas are usually dominated by the C2 Swan bands. In this paper, the use of the C2 Swan bands for estimating the gas temperature in CO2 microwave plasmas is assessed. State by state fitting is employed to check the correctness of assuming a Boltzmann distribution for the rotational and vibrational distribution functions and, within statistical and systematic uncertainties, the C2 Swan band can be fitted accurately with a single temperature for rotational and vibrational levels. The processes leading to the production of the C2 molecule and particularly its

d

3

Π

g

state are briefly reviewed as well as collisional relaxation times of the latter. It is concluded that its rotational temperature can be associated to the gas temperature of the CO2 microwave plasma and the results are moreover cross-checked by adding a small amount of N2 in the discharge and measuring the CN violet band system. The 2.45 GHz plasma source is analyzed in the pressure range 180–925 mbar, for input microwave powers ranging from 0.9 to 3 kW and with gas flow rates of 5–100 l min−1. An intense C2 Swan bands emission spectrum can be measured only when the plasma is operated in contracted regime. A unique temperature of about 6000 ± 500 K is obtained for all investigated conditions. A spectroscopic database is constructed using the recent compilation and calculations by Brooke et al (2013 J. Quant. Spectrosc. Radiat. Transfer
124 11–20) of the line strengths and molecular constants for the C2 (d

3

Π

g

−a

3

Π

u

) Swan bands system and made available as supplementary material in a format compatible with the open source MassiveOES software.
Combining Floquet and Lyapunov techniques for time-dependent problems in optomechanics and electromechanics
Authors: Pietikäinen Iivari , Černotík Ondřej , Filip Radim
Published: April 2020

Cavity optomechanics and electromechanics form an established field of research investigating the interactions between electromagnetic fields and the motion of quantum mechanical resonators. In many applications, linearised form of the interaction is used, which allows for the system dynamics to be fully described using a Lyapunov equation for the covariance matrix of the Wigner function. This approach, however, is problematic in situations where the Hamiltonian becomes time dependent as is the case for systems driven at multiple frequencies simultaneously. This scenario is highly relevant as it leads to dissipative preparation of mechanical states or backaction-evading measurements of mechanical motion. The time-dependent dynamics can be solved with Floquet techniques whose application is, nevertheless, not straightforward. Here, we describe a general method for combining the Lyapunov approach with Floquet techniques that enables us to transform the initial time-dependent problem into a time-independent one, at the acceptable cost of enlarging the drift and diffusion matrix. We show how the lengthy process of applying the Floquet formalism to the original equations of motion and deriving a Lyapunov equation from their time-independent form can be simplified with the use of properly defined Fourier components of the drift matrix of the original time-dependent system. We then use our formalism to comprehensively analyse dissipative generation of mechanical squeezing beyond the rotating wave approximation. Our method is applicable to various problems with multitone driving schemes in cavity optomechanics, electromechanics, and related disciplines.
A recurrent plot based stochastic nonlinear ray propagation model for underwater signal propagation
Authors: Haiyang Yao , Haiyan Wang , Yong Xu , Kurths Juergen
Published: April 2020

A stochastic nonlinear ray propagation model is proposed to carry out an exploration of the nonlinear ray theory in underwater signal propagation. The recurrence plot method is proposed to quantify the ray chaos and stochastics to optimize the model. Based on this method, the distribution function of the control parameter δ is derived. Experiments and simulations indicate that this stochastic nonlinear ray propagation model provides a good explanation and description on the stochastic frequency shift in underwater signal propagation.
High permeability and bimodal resonance structure of flaky soft magnetic composite materials*
Authors: Liu Xi , Wu Peng , Wang Peng , Wang Tao , Qiao Liang , Li Fa-Shen
Published: April 2020

We establish a theoretical bimodal model for the complex permeability of flaky soft magnetic composite materials to explain the variability of their initial permeability. The new model is motivated by finding the two natural resonance peaks to be inconsistent with the combination of the domain wall resonance and the natural resonance. In the derivation of the model, two relationships are explored: the first one is the relationship between the number of magnetic domains and the permeability, and the second one is the relationship between the natural resonance and the domain wall resonance. This reveals that the ball milling causes the number of magnetic domains to increase and the maximum initial permeability to exist after 10 h of ball milling. An experiment is conducted to demonstrate the reliability of the proposed model. The experimental results are in good agreement with the theoretical calculations. This new model is of great significance for studying the mechanism and applications of the resonance loss for soft magnetic composite materials in high frequency fields.
The impact of honesty and trickery on a Bayesian quantum prisoners’ dilemma game*
Authors: Liu Bo-Yang , Zhao Xin , Dai Hong-Yi , Zhang Ming , Liao Ying , Guo Xiao-Feng , Gao Wei
Published: April 2020

To explore the influence of quantum information on the common social problem of honesty and trickery, we propose a Bayesian model for the quantum prisoners’ dilemma game. In this model, the players’ strategy formation is regarded as a negotiation of their move contract based on their types of decision policies, honesty or trickery. Although the implementation of quantum information cannot eliminate tricky players, players in our model can always end up with higher payoffs than in the classical game. For a good proportion of a credibility parameter value, a rational player will take an honest action, which is in remarkable contrast to the observation that players tend to defect in the classical prisoners’ dilemma game. This research suggests that honesty will be promoted to enhance cooperation with the assistance of quantum information resources.
A high-pressure study of Cr3C2 by XRD and DFT*
Authors: Xiong Lun , Li Qiang , Yang Cheng-Fu , Xie Qing-Shuang , Zhang Jun-Ran
Published: April 2020

The equation of state (EOS) of Cr3C2 at high pressure is studied by the synchrotron radiation x-ray diffraction (XRD) in a diamond anvil cell (DAC) at ambient temperature, and density functional theory (DFT). The XRD analysis shows that the orthorhombic structure is maintained to a maximum pressure of 44.5 GPa. The XRD data show that the bulk modulus is K
0 = 292 (18) GPa with

K
0
′

=
3.25
(
0.85
)

. In addition, the high-pressure compression behavior of Cr3C2 is studied by first principles calculations. The obtained bulk modulus of Cr3C2 is 323 (1) GPa.
Reversion of weak-measured quantum entanglement state*
Authors: Du Shao-Jiang , Peng Yonggang , Feng Hai-Ran , Han Feng , Yang Lian-Wu , Zheng Yu-Jun
Published: April 2020

We theoretically study the reversible process of quantum entanglement state by means of weak measurement and corresponding reversible operation. We present a protocol of the reversion operation in two bodies based on the theory of reversion of single photon and then expend it in quantum communication channels. The theoretical results demonstrate that the protocol does not break the information transmission after a weak measurement and a reversible measurement with the subsequent process in the transmission path. It can reverse the perturbed entanglement intensity evolution to its original state. Under the condition of different weak measurement intensity the protocol can reverse the perturbed quantum entanglement system perfectly. In the process we can get the classical information described by information gain from the quantum system through weak measurement operation. On the other hand, in order to realize complete reversibility, the classical information of the quantum entanglement system must obey a limited range we present in this paper in the reverse process.
Dynamical analysis for hybrid virus infection system in switching environment*
Authors: Li Dong-Xi , Zhang Ni
Published: April 2020

We investigate the dynamical behavior of hybrid virus infection systems with nonlytic immune response in switching environment, which is modeled as a stochastic process of telegraph noise and represented as a multi-state Markov chains. Firstly, The existence of unique positive solution and boundedness of the new hybrid system is proved. Furthermore, the sufficient conditions for extinction and persistence of virus are established. Finally, stochastic simulations are performed to test and demonstrate the conclusions. As a consequence, our work suggests that stochastic switching environment plays a crucial role in the process of virus prevention and treatment.
Irradiation study of liquid crystal variable retarder for Full-disk Magneto-Graph payload onboard ASO-S mission*
Authors: Hou Jun-Feng , Wang Hai-Feng , Wang Gang , Luo Yong-Quan , Li Hong-Wei , Zhang Zhen-Long , Wang Dong-Guang , Deng Yuan-Yong
Published: April 2020

The Advanced Space-based Solar Observatory (ASO-S) is a mission proposed by the Chinese Solar Physics Community. As one of the three payloads of ASO-S, the Full-disc Magneto-Graph (FMG) will measure the photospheric magnetic fields of the entire solar disk with high spatial and temporal resolution, and high magnetic sensitivity, where liquid crystal variable retarder (LCVR) is the key to whether FMG can achieve its scientific goal. So far, there is no space flight experience for LCVR. Therefore, irradiation study for LCVRs becomes more important and urgent in order to make sure their safety and reliability in space application. In this paper, λ irradiation, proton irradiation, and ultra-violet (UV) irradiation are tested for LCVRs respectively. The optical and chemical properties during irradiation tests are measured and analyzed. For optical properties, there is no significant change in those parameters FMG payload concerned except the retardation. Although there is no drastic degradation in the retardation versus voltage during irradiations, the amount of retardation variation is much higher than the instrument requirements. Thus, an in-flight retardation versus voltage should be added in FMG payload, reducing or even avoiding the impact of retardation change. For chemical properties, the clearing point and birefringence of the LC materials almost have no change; the ion density dose not change below 60 krad[Si], but begin to increase dramatically above 60 krad[Si].
High-performance frequency stabilization of ultraviolet diode lasers by using dichroic atomic vapor spectroscopy and transfer cavity*
Authors: Shen Danna , Ding Liangyu , Zhang Qiuxin , Zhu Chenhao , Wang Yuxin , Zhang Wei , Zhang Xiang
Published: April 2020

We develop a high-performance ultraviolet (UV) frequency stabilization technique implemented directly on UV diode lasers by combining the dichroic atomic vapor laser lock and the resonant transfer cavity lock. As an example, we demonstrate a stable locking with measured frequency standard deviations of approximately 200 kHz and 300 kHz for 399 nm and 370 nm diode lasers in 20 min. We achieve a long-term frequency drift of no more than 1 MHz for the target 370 nm laser within an hour, which is further verified with fluorescence count rates of a single trapped 171Yb+ ion. We also find strong linear correlations between lock points and environmental factors such as temperature and atmospheric pressure. Our approach provides a simple and stable solution at a relatively low cost, and features flexible control, high feedback bandwidth and minimal power consumption of the target UV laser.
Spectro-polarimetric observations at the NVST: I. instrumental polarization calibration and primary measurements
Authors: Hou Jun-Feng , Xu Zhi , Yuan Shu , Chen Yu-Chao , Peng Jian-Guo , Wang Dong-Guang , Xu Jun , Deng Yuan-Yong , Jin Zhen-Yu , Ji Kai-Fan , Liu Zhong
Published: April 2020

This paper is devoted to the primary spectro-polarimetric observation performed at the New Vacuum Solar Telescope (NVST) of China since 2017, and our aim is to precisely evaluate the real polarimetric accuracy and sensitivity of this polarimetry by using full Stokes spectro-polarimetric observations of the photospheric line Fe I 532.4 nm. In the work, we briefly describe the salient characteristic of the NVST as a polarimeter in terms of technology and then characterize its instrumental polarization based on the operation in 2017 and 2019. It is verified that the calibration method utilizing the instrumental polarization calibration unit (ICU) is stable and credible. The calibration accuracy can reach up to 3 × 10−3. Based on the scientific observation of NOAA Active Region 12645 on 2017 April 5, we estimate that the residual cross-talk from StokesIto StokesQ,UandV, after the instrumental polarization calibration, is about 4 × 10−3on average, which is consistent with the calibration accuracy and close to the photon noise. The polarimetric sensitivity (i.e., the detection limit) for polarized light is of the order of 10−3with an integration time over 20 s. Slow modulation rate is indeed an issue for the present system. The present NVST polarimeter is expected to be integrated with a high-order adaptive optics system and a field scanner to realize 2D vector magnetic field measurements in the following instrumentation update.
A study of type I X-ray bursts from an NS accreting pure helium
Authors: Ma Yan-Cun , Liu He-Lei , Zhu Chun-Hua , Wang Zhao-Jun , Li Lin , Lü Guo-Liang
Published: April 2020

Using the Modules for Experiments in Stellar Astrophysics (MESA) code, we investigate Type I X-ray bursts (XRBs) produced by neutron stars (NSs) accreting pure helium, which are called intermediate XRBs in observations. We simulate 21 models for intermediate XRBs with various mass-accretion rates (Ṁ) from 2.5 × 10−8 to 5 × 10−10
M
⊙ yr−1. Compared with normal XRBs, in which the NS accretes matter with solar metallicity, intermediate XRBs have higher luminosity and longer recurrence time, which are essentially consistent with observations. We find that the recurrence time of intermediate XRBs is proportional to Ṁ
−2.0.
The column density structure of Orion A depicted by N-PDF
Authors: Ma Yue-Hui , Wang Hong-Chi , Li Chong , Yang Ji
Published: April 2020

We have conducted a large-field simultaneous survey of 12CO, 13CO and C18O J = 1 – 0 emission toward the Orion A giant molecular cloud (GMC) with a sky coverage of ∼4.4 deg2 using the Purple Mountain Observatory (PMO)-13.7 m millimeter-wavelength telescope. We use the probability distribution function of the column density (N-PDF) to investigate the distribution of molecular hydrogen in the Orion A GMC. The H2 column density, derived from the 13CO emission, of the GMC is dominated by a log-normal distribution in the range from ∼ 4 × 1021 to ∼ 1.5 × 1023 cm−2 with excesses both at the low-density and high-density ends. The excess of the low-density end is possibly caused by an extended and low-temperature (∼10 K) component with velocities in the range of 5 – 8 km s−1. Compared with the northern sub-regions, the southern sub-regions of the Orion A GMC contain less gas with column density in N
H2
> 1.25 × 1022 cm−2. The dispersions of the N-PDFs of the sub-regions are found to correlate with the evolutionary stages of the clouds across the Orion A GMC. The structure hierarchy of Orion A GMC is explored with the DENDROGRAM algorithm, and it is found that the GMC is composed of two branches. All structures except one in the tree have virial parameters less than 2, indicating self-gravity is important on the spatial scales from ∼0.3 to ∼4 pc. Although power-laws and departures from lognormal distributions are found at the high-density end of N-PDFs for active star-forming regions, the N-PDFs of structures in the Orion A GMC are predominantly lognormal on scales from R∼0.4 to 4 pc.
Chinese sunspot drawings and their digitization – (II) accuracy analysis for digitized sunspot hand-drawing records of Yunnan Observatories
Authors: Peng Yang , Luo Xiao-Yu , Zeng Shu-Guang , Deng Lin-Hua , Zheng Sheng , Lin Gang-Hua , Cheng Yu-Lin , Tao Jin-Ping , Feng Yong-Li
Published: April 2020

Sunspots are the most striking and easily observed magnetic structures of the Sun, and statistical analysis of solar historical data could reveal a wealth of information on the long-term variation of solar activity cycle. The hand-drawn sunspot records of Yunnan Observatories, Chinese Academy of Sciences have been accumulating for more than 60 years, and nearly 16 000 images have been preserved. In the future, the observation mode of recording sunspots by hand-drawing will be replaced inevitably by digital images observed either at ground or in space. To connect the hand-drawn sunspot data and the purely digital sunspot data in future, it is necessary to analyze the systematic errors of the data which are observed by the two observation modes in the period of transition. In this paper, we choose 268 round sunspots (H-type in modified Zurich sunspot classification) from the drawing of Yunnan Observatories to compare their positions and areas with the CCD observations made by Helioseismic and Magnetic Imager (HMI) on board Solar Dynamic Observatory (SDO) and Global Oscillation Network Group (GONG). We find that the latitude and longitude accuracy of hand-drawn sunspot are within −0.127 and 2.29 degree respectively, and the area accuracy is about 16.36 sunspot unit (μHem). Systematic errors apparently decrease with large sunspot.
Burning fraction, radial transport, and steady state profiles of multi-species particles in CFETR burning plasmas
Authors: Lin W.S. , Wang X.G. , Xiao C.J. , Wang Z.H. , Kong D.F. , Lang Y.
Published: April 2020

The burning fraction of fuel particles is a crucial issue for future fusion reactors. In order to achieve the high tritium burning fraction required by China Fusion Engineering Test Reactor (CFETR) engineering design, fueling depths and quantities should be estimated by particle control analysis for different scenarios. Thus, in this paper, a multi-species fluid model of deuterium-tritium (D-T) fusion plasmas is applied to study radial transport and profile evolution with CFETR parameters under different fueling conditions. In the model, alpha particles are treated with a slowing down model and diffusion coefficients are introduced according to

τ

E
_
9
8

. Then, in such a self-consistent burning plasma simulation, the results show that the fusion reaction and fueling parameters effect remarkably changes the shape of D/T profiles, while to alphas and helium ash however, the effect of the fueling parameters is much weaker. It is also seen that the burning fraction is increased substantially with the fueling depth, and significantly affected by particle confinement. Furthermore, by substantially raising the D:T ratio to the regime of above unity, the burning fraction can be increased notably, but with a cost of a certain level of fusion power reduction.
Development of an in situ injectable hydrogel containing hyaluronic acid for neural regeneration
Authors: Nguyen Linh T B , Hsu Chia-Chen , Ye Hua , Cui Zhanfeng
Published: April 2020

In this work, a novel enzymatically crosslinked injectable hydrogel comprising hyaluronic acid (HyA), dopamine (DA), and 3-(4-hydroxyphenyl) propionic acid (HPA) conjugates was successfully developed. To the best of our knowledge, it is the first time that HPA is conjugated to a HyA-based backbone. In situ hydrogelation of HyA-DA-HPA occurred in the presence of hydrogen peroxide (H2O2) as an oxidant and horseradish peroxidase (HRP) as a catalyst. Proton nuclear magnetic resonance and Fourier transform infrared spectroscopy were used to characterize the chemical reactions between HyA, DA, and HPA. Gel formation completed between 3 s to 5 min depending on the concentrations of polymer, HRP, and H2O2. Crosslinked HyA-DA-HPA gels acquired storage moduli ranging from ∼100 Pa to ∼20 000 Pa (at f = 2000 rad s−1). Biocompatibility of the hydrogels was examined with human mesenchymal stem cells (hMSCs) and human induced pluripotent stem cell-derived neural stem cells. The hydrogels made of 2.0 w/v% HyA-DA-HPA hydrogels, 0.24 U ml−1 HRP and ≤ 0.5 µmol ml−1 H2O2 were found biocompatible with hMSCs cultured on and encapsulated within the hydrogels. Since HyA serves as a backbone of the extracellular matrix in the central nervous system (CNS) and DA acquires the ability to restore dopaminergic neurons, use of this injectable HyA-DA-HPA hydrogel for stem cell transplantation is a potential treatment strategy for CNS repair and regeneration.
The effect of surge on riverine flood hazard and impact in deltas globally
Authors: Eilander Dirk , Couasnon Anaïs , Ikeuchi Hiroaki , Muis Sanne , Yamazaki Dai , Winsemius Hessel C , Ward Philip J
Published: April 2020

Current global riverine flood risk studies assume a constant mean sea level boundary. In reality high sea levels can propagate up a river, impede high river discharge, thus leading to elevated water levels. Riverine flood risk in deltas may therefore be underestimated. This paper presents the first global scale assessment of the joint influence of riverine and coastal drivers of flooding in deltas. We show that if storm surge is ignored, flood depths are significantly underestimated for 9.3% of the expected annual population exposed to riverine flooding. The assessment is based on extreme water levels at 3433 river mouth locations as modeled by a state-of-the-art global river routing model, forced with a multi-model runoff ensemble and bounded by dynamic sea level conditions derived from a global tide and surge reanalysis. We first classified the drivers of riverine flooding at each location into four classes: surge-dominant, discharge-dominant, compound-dominant or insignificant. We then developed a model experiment to quantify the effect of surge on flood hazard and impacts. Drivers of riverine flooding are compound-dominant at 19.7% of the locations analyzed, discharge-dominant at 69.2%, and surge-dominant at 7.8%. Compared to locations with either surge- or discharge-dominant flood drivers, locations with compound-dominant flood drivers generally have larger surge extremes and are located in basins with faster discharge response and/or flat topography. Globally, surge exacerbates 1-in-10 years flood levels at 64.0% of the locations analyzed, with a mean increase of 11 cm. While this increase is generally larger at locations with compound- or surge-dominant flood drivers, flood levels also increase at locations with discharge-dominant flood drivers. This study underlines the importance of including dynamic downstream sea level boundaries in (global) riverine flood risk studies.