bluuebunny/crossref_metadata_2025 huggingface dataset:
Fuzzy Estimate of the Development of Passenger Cars Production in the Czech Republic
Authors: Hašková Simona
Published: January 2021

The global outbreak of the COVID-19 and the measures taken, disrupted fundamentally economies around the world. Almost all sectors were affected. The experts have long emphasised the Czech economy’s dependence on the automotive industry. Car producers and companies linked to them have been loaded by severe difficulties after the pandemic outbreak. The article shows one of the constructive ways how to forecast a change in the passenger cars production in the Czech Republic in 2020. Metodologically we lean on a procedure of the fuzzy approach. The prediction itself cannot be derived from the series of historical data of the variables that are related to the target output variable as shown in the fuzzy prediction of GDP for 2018 by this author. Due to the extreme situation caused by pandemic outbreak, the role of expert predictions come intensively into play with their outcomes becoming the set of input data to the fuzzy model. The result of the fuzzy forcast of a change in the cars production in CZ for 2020 shows a greater drop than the official statistical model claims.
A Bibliometric Analysis of Branding Trends: Does Irrationality Really Matter?
Authors: Majerova Jana , Gajanova Lubica , Nadanyiova Margareta
Published: January 2021

Irrationality and its transposition into theory of consumer behaviour is generally considered to be one of the leading trends in contemporary managerial research. It becomes to be notoriety without need of its verification in conditions of specifics of managerial practice across products and markets. However, there are still platforms for discussion about its impact on current state of knowledge. One of these platforms is brand management. On the one hand – the most dominant brand value source is its image creating attribute where irrationality has its undisputable position but on the other hand – qualitative attributes of brand are still considered as significant. Thus, the rationality is highlighted in scope of branding. Therefore, the schism between rationality and irrationality is visible. The aim of this paper is to identify the position of irrationality in the branding trendology. Methodologically, VOSviewer has been used as a basic research platform for the bibliometric analysis of contemporary scientific literature. We have found out, that there is a significant discrepancy between trends in branding theory worldwide and in Slovak Republic. Thus, we create platform to discuss about the applicability of branding patterns which have been modified in scope of irrationality and questioning the existence of Homo Oeconomicus.
Impact of Dividend Policy on the Market Value of the Company
Authors: Eryomin Ivan , Likhacheva Olga , Chernikova Lyudmila
Published: January 2021

The article is devoted to the analysis and assessment of the impact of dividends on the market value of the company. The study is based on data from company reports and statistics from the Moscow Exchange. This paper presents a regression analysis of a choice consisting of 1) 20 systems of Russian companies and 2) 5 largest companies in the oil and gas sector for the period 2013-2019. The regression results show that dividends have a positive effect on capitalization only if the policy is based on the residual principle. The conclusions made in the work, which provide recommendations and a statistical assessment of dependence, can find practical application in determining the dividend policy of an organization and predicting changes in the capitalization of companies.
Innovation and its importance in the context of a company’s marketing strategy
Authors: Olexova Veronika , Gogolova Martina
Published: January 2021

The current business environment is characterized by high competition between companies as well as global challenges and growing technological progress. Businesses must constantly adapt to changes in the business environment, changes in the market environment and the constantly changing requirements of customers. There are currently several tools and ways to respond to these changes. One of the most important areas can be considered corporate strategy, because it determines the basic direction of the company. An important area is also marketing, which affects the overall business activity. Determining the right marketing strategy has an important impact on the overall direction of the company. Another important element of the current time in the field of business is innovation, which can be considered a basic prerequisite for the success of the company. The issue of innovation management is currently one of the basic conditions for maintaining a market position and maintaining competitiveness. The aim of the article is to point out the theoretical basis of the corporate strategy, marketing strategy and the importance of innovation in business. Subsequently, based on secondary findings, we analyze available selected data related to innovation in Slovakia.
Impacts of COVID-19 on the Real Estate Market in the Czech Republic
Authors: Hromada Eduard
Published: January 2021

The article deals with the description of the impacts of COVID-19 on the real estate market in the Czech Republic. The article focuses on the housing market - sales and rentals of apartments. The article contains graphs that show the development before COVID-19 and during COVID-19. Trends are indicated as the real estate market will develop in the next period. All results published in this article were created using the EVAL software, which the author of the article has been developing since 2007. This software continuously maps real estate advertising within all cities in the Czech Republic.
Long memory in stock returns: Evidence from the Eastern European markets
Authors: Dias Rui , Heliodoro Paula , Alexandre Paulo , Santos Hortense , Farinha Ana
Published: January 2021

This essay aims to analyze the impact of the 2020 global pandemic on the memory properties of the Eastern Europe stock markets, from the period between 1 January 2016 to 2 September 2020, the sample was divided in two subperiods: 1 January 2016 to 30 August 2019 (before Covid 19) and 2 September 2019 to 2 September 2020 (after Covid 19). To perform this analysis, different approaches were undertaken to analyze whether if: (i) the global pandemic (Covid-19) accentuated the exponentsDetrended Fluctuation Analysis (DFA)and theDetrended Cross-CorrelationAnalysis (𝑝𝐷𝐶𝐶𝐴) in the Eastern European stock markets?. The daily returns do not have normal distributions, they have negative asymmetries, leptocubtic, and also exhibit conditional heteroscedasticity. The exponents Detrended Fluctuation Analysis (DFA), during the Covid-19 period, range from 0.64 to 0.75, showing significant long memories in all markets, except for the SLOVAKIA market (0.45). When we compared the 2 subperiods, we found that 41 pairs of markets have cross-correlation coefficients without trend ( λDCCA) strong (out of 45 possible), and 4 pairs of markets decreased the 𝑟ℎ𝑜𝐷𝐶𝐶𝐴 in particular the markets ESTONIA-SLOVAKIA, LITHUANIA-SLOVAKIA, HUNGARY-SLOVAKIA, POLAND-SLOVAKIA. These findings show that the assumption of the market efficiency hypothesis may be in question, since the prediction of market movement can be improved if we consider the out-of-lag movements of the other markets, enabling the occurrence of arbitrage operations and some difficulties in portfolio diversification.
1′-Acetoxychavicol Acetate from Alpinia galanga Represses Proliferation and Invasion, and Induces Apoptosis via HER2-signaling in Endocrine-Resistant Breast Cancer Cells
Authors: Pradubyat Nalinee , Giannoudis Athina , Elmetwali Taha , Mahalapbutr Panupong , Palmieri Carlo , Mitrpant Chalermchai , Ketchart Wannarasmi
Published: January 2021

Estrogen receptor-positive breast cancer patients have a good prognosis, but 30% of these patients will experience recurrence due to the development of resistance through various signaling pathways. This study aimed to evaluate the mode of anticancer effects of 1′-acetoxychavicol acetate, which is isolated from the rhizomes of Alpinia galanga in estrogen receptor positive (MCF7) human epidermal growth factor receptor 2-overexpressed (MCF7/HER2), and endocrine-resistant breast cancer cells (MCF7/LCC2 and MCF7/LCC9). 1′-Acetoxychavicol acetate showed antiproliferation in a concentration- and time-dependent fashion and had higher potency in human epidermal growth factor receptor 2-overexpressed cell lines. This was associated with down-regulation of human epidermal growth factor receptor 2, pERK1/2, pAKT, estrogen receptor coactivator, cyclin D1, and MYC proto-oncogene while in vivo and significant reduction in the tumor mass of 1′-acetoxychavicol acetate-treated zebrafish-engrafted breast cancer groups. The anti-invasive effects of 1′-acetoxychavicol acetate were confirmed in vitro by the matrigel invasion assay and with down-regulation of C – X-C chemokine receptor type 4, urokinase plasminogen activator, vascular endothelial growth factor, and basic fibroblast growth factor 2 genes. The down-regulation of urokinase plasminogen activator and fibroblast growth factor 2 proteins was also validated by molecular docking analysis. Moreover, 1′-acetoxychavicol acetate-treated cells exhibited lower expression levels of the anti-apoptotic Bcl-2 and Mcl-1 proteins in addition to enhanced stress-activated kinases/c-Jun N-terminal kinase 1/2 and poly-ADP ribose polymerase cleavage, indicating apoptotic cell induction by 1′-acetoxychavicol acetate. Moreover, 1′-acetoxychavicol acetate had higher potency in human epidermal growth factor receptor 2-overexpressed cell lines regarding its inhibition on human epidermal growth factor receptor 2, pAKT, pERK1/2, PSer118, and PSer167-ERα proteins. Our findings suggest 1′-acetoxychavicol acetate mediates its anti-cancer effects via human epidermal growth factor receptor 2 signaling pathway.
Eyelid Surgery in Gravesʼ Orbitopathy
Authors: Hintschich Christoph
Published: January 2021

Patients with Gravesʼ orbitopathy often develop eyelid changes. These may be the result of a volume effect or a malposition. Both dermatochalasis with fat tissue increase and eyelid retraction may lead to functional or aesthetic impairment. The present article reviews indications, timing and principles for corrective eyelid surgery. If at all possible, surgical eyelid correction in Gravesʼ orbitopathy should be performed once the disease became inactive and stabile. Surgical details of eyelid lengthening procedures for upper and lower eyelid retraction are presented. Meanwhile anterior blepharotomy became the primary procedure for upper eyelid lengthening. However, there is no such standard procedure for lower eyelid lengthening, although it is recommended to use a spacer. For blepharoplasty it is mandatory to distinguish between orbital fat prolapse and subbrow fat pad. A prolapse of the lacrimal gland should not be missed and generally, skin excision performed
sparingly.
IntraMolecular Diels–Alder Reactions of Vinylarenes and Alkynyl Arenes (the IMDAV Reaction)
Authors: Zubkov Fedor I. , Krishna Gaddam , Grudinin Dmitry G. , Nikitina Eugeniya V.
Published: January 2021

This comprehensive review summarizes the published literature data concerning the intramolecular Diels–Alder reactions of vinylarenes (the IMDAV reaction) and alkynyl arenes from 1970 to 2019, and covers mainly intramolecular [4+2] cycloaddition reactions of vinyl- or acetylene-substituted furans, thiophenes, pyrroles, indoles, imidazoles, benzenes, and naphthalenes, in which the unsaturated substituent is linked directly to an arene moiety. The selected area of the Diels–Alder reaction differs from other forms of [4+2] cycloadditions due to the uniqueness of the diene fragment, which, along with an exocyclic multiple bond, includes the double bond of an aromatic or heteroaromatic nucleus in its system. Thus, during the formation of the [4+2] cycloaddition intermediate, the aromaticity of furan, thiophene and even benzene rings is broken, leading, as a rule, to the formation of heterocyclic structures rarely accessible by other methods, in contrast to the majority of intermolecular Diels–Alder reactions, with the highest degree of chemo-, regio-, and diastereoselectivity. Therefore, the IMDAV approach is often used for the synthesis of naturally occurring and bioactive molecules, which are also discussed in this review alongside other applications of this reaction. Whenever possible, we have tried to avoid examples of radical, photochemical, oxidative, precious-metal-complex-catalyzed cyclizations and other types of formal [4+2] cycloadditions, focusing on thermal Diels–Alder reactions in the first step, according to the classical mechanism. The second stage of the process, aromatization, is unique for many initial substrates, and hence considerable attention in this overview is given to the detailed description of the reaction mechanisms.

1 Introduction

2 IMDAV Reactions of Vinylfurans

2.1 Alkenes as Internal Dienophiles

2.2 Alkynes and Allenes as Internal Dienophiles

3 IMDAV Reactions of Vinylthiophenes

3.1 Alkenes as Internal Dienophiles

3.2 Alkynes as Internal Dienophiles

4 IMDAV Reactions of Vinylbenzothiophenes

5 IMDAV Reactions of Vinylpyrroles

6 IMDAV Reactions of Vinylindoles

6.1 Alkenes as Internal Dienophiles

6.2 Alkynes as Internal Dienophiles

7 IMDAV Reactions of Styrenes and Vinylnaphthalenes

7.1 Alkenes as Internal Dienophiles

7.2 Alkynes as Internal Dienophiles

7.3 Alkynes as Internal Dienophiles in Aryl Acetylenes (the Intramolecular Dehydro Diels–Alder Reaction)

8 IMDAV Reactions of Vinylimidazoles, Vinylisoxazoles and Vinylpyridines

9 Conclusion

10 Abbreviations
Perioperative Management of Nasal Septal Perforation: A Case Series and Review
Authors: Wakeford William James , Shamil Eamon , D'Souza Alwyn Ray
Published: January 2021

Nasal septal perforation is a prevalent pathology, and its successful treatment remains a significant challenge. Surgical closure is complex, and there are a plethora of accounts of various surgical techniques within the existing literature. Much less has been written about perioperative considerations, which are arguably just as important. This article therefore focuses predominantly on the pre and postoperative management of patients with septal perforation. By drawing both on the existing literature and a series of 64 cases managed over several years by our department, this review aims to consolidate guidance on patient selection, timing of surgical intervention, postoperative splinting, use of antibiotics, and patient advice. It is clear that the size of the perforation (relative to the size of the septum), health of surrounding mucosa, and the systemic health and age of the patient remain essential considerations in patient selection and operative timing. Internal and external splints are widely used to good effect, but the role of nasal packing is less clear-cut. This article suggests packing, but with an increasing preference for NasoPore over BIPP (bismuth iodoform paraffin paste). Use of prophylactic antibiotics remains controversial. The complete closure rate for the series presented here was 81.3%, with an average perforation diameter of 15.1 mm (range: of 6–32 mm), and that for perforations with a diameter below 22 mm was 97.9%.
Role of Multidisciplinary Care in the Management of Hepatocellular Carcinoma
Authors: Byrd Kia , Alqahtani Saleh , Yopp Adam C. , Singal Amit G.
Published: January 2021

Despite advances in treatment options for hepatocellular carcinoma (HCC), 5-year survival for HCC remains below 20%. This poor survival is multifactorial but is partly related to underuse of curative treatment in clinical practice. In light of growing treatment options, delivered by different types of providers, optimal management requires input from multiple specialties. A multidisciplinary approach has been evolving over the past couple of decades, bringing different specialists together to develop a therapeutic plan to treat and manage HCC, which significantly increases timely guideline-concordant treatment and improves overall survival. The present review attempts to highlight the need for such a multimodal approach by providing insights on its potential structure and impact on the various aspects of HCC management.
Challenges of Diagnosing Hyponatremic Syndromes in Pulmonary and Extra Pulmonary Tuberculosis
Authors: Ewa Atana U. , Ochang Ernest A. , Inaku Keneth O. , Adams Emmanuel B. , Anachuna Kingsley C. , Imoke Echeng J. , Cobham Antigha I. , Brown Ekaete S.
Published: January 2021

Introduction Pulmonary tuberculosis (PTB) is one of the rare pulmonary infections causing hyponatremia (serum sodium ˂135 mmol/L) and severe hyponatremia (serum sodium ˂125 mmol/L). Although the major cause of hyponatremia in TB patients is syndrome of inappropriate antidiuretic hormone (SIADH) secretion, cerebral salt wasting syndrome (CSWS) can occur and requires evidence of inappropriate urinary salt losses and reduced arterial blood volume. Adrenal insufficiency (AI) is rare in TB with scanty literature describing it. The two reported cases highlight three possible causes of severe symptomatic hyponatremia in TB pleural effusion and disseminated TB, their treatment modalities, and the need to increase the index of suspicion to diagnose TB hyponatremia in children.

Case Report Case 1: a 10-year-old girl with TB pleural effusion who developed recurrent hyponatremia in the first few weeks of anti-TB treatment which was responsive to sodium correction. Case 2: an 8-year-old girl presenting to our facility with presumptive TB. She deteriorated over several months and progressed to disseminated TB with AI.

Discussion Early diagnosis and prompt and correct treatment of TB hyponatremia cannot be overemphasized, as AI, SIADH secretion, and CSWS, each require different therapeutic regimens, most especially AI on its own poses a huge clinical challenge.

Conclusion A high index of suspicion, with intensified case finding at all levels of care, is necessary to identify and manage children with TB hyponatremia because early diagnosis and prompt treatment is lifesaving.
Why Africa cannot prosecute (or even educate) its way out of road accidents: insights from Ghana
Authors: Boateng Festival Godwin
Published: January 2021

The paper sheds light on the problem of the growing embracement of penal populism (fines and prison sentences) as a measure for dealing with road trauma in Africa through a case study of Ghana. It argues that the policy of hunting for rogue drivers to make roads safer in the continent is as ineffective as killing mosquitoes one by one to control malaria. The best remedy is to drain the swamps in which they breed. The swamps, in respect of road trauma in Africa, are the ineffective public transportation systems and the focus on constructing more expensive roads, which encourage the importation of more old cars, and a high dependence on privately run, deregulated commercial passenger transport sectors that are structurally embedded in driver exploitation. These factors coupled with police corruption and the traffic congestions induced by private capital-driven land-use patterns are what underlie safety-adverse driving and road transport problems generally in the continent. More fundamentally, the paper argues that the law enforcement-heavy approach to road trauma essentializes African drivers as having a danger-prone driving culture. This generates (in)discipline concerns that act as a red herring by deflecting attention from the structural factors undermining road safety in the continent: the continuing effects of neoliberal programs funded by international development bodies, and the profiteering and political interests of powerful coalitions of private transport owners’ unions and public officials that have molded and entrenched the continent’s road transport sectors in its present problematic forms to serve particular purposes. The paper hopes to move road safety conversations in Africa away from the present thinking that enforcing greater punishments against drivers, rather than addressing the broader societal systems whose effects manifest in the road transport sector, is “the” answer to the unacceptably high rate of carnages on the continent’s roads.
Single-photon emission computed tomography in the scattering medium with the property of “scattering straight back”
Authors: Tereshchenko S. A. , Lysenko A. Yu.
Published: January 2021

The problem of radiation scattering in integral reconstruction algorithms for single-photon emission computed tomography (SPECT) has not been completely solved. This is primarily due to the fact that the radiation transport equation (RTE) does not have an exact analytical solution in general form for a scattering indicatrix corresponding to a real medium. A special form of the scattering indicatrix is proposed here that corresponds to a scattering medium with a property named “scattering straight back.” With this scattering indicatrix, it is possible to obtain an exact analytical solution of the RTE with exact boundary conditions for an arbitrary distribution of radiation sources. From this exact solution, a new expression can be obtained for the measured data, named as generalized attenuated exponential Radon transform. A new definition of projections is proposed to obtain an exact solution of the inverse tomographic problem. This solution has the same level of rigor as the exponential Radon transform for a purely absorbing medium. The proposed algorithm is compared with the traditional SPECT algorithm (the inverse exponential Radon transform) using Monte Carlo simulation based on the nuclear physics software package Geant4. It is demonstrated that the new method is superior to the traditional method in terms of both the standard deviation criterion and better visual distinction of the details in the reconstructed tomogram. The results obtained can be used to improve the existing algorithms for image reconstruction in SPECT, as well as to aid in developing new designs of emission tomographs.
Unsteady flow regimes in arrow-shaped micro-mixers with different tilting angles
Authors: Mariotti A. , Galletti C. , Brunazzi E. , Salvetti M. V.
Published: January 2021

Two arrow-shaped micro-mixers, obtained from the classical T-shaped geometry by tilting downward the inlet channels, are considered herein. The two configurations, having different tilting angle values, have been chosen since they show significantly different flow topologies and mixing performances at low Reynolds numbers. In the present paper, we use both experimental flow visualizations and direct numerical simulations to shed light on the mixing behavior of the two configurations for larger Reynolds numbers, for which the mixers present unsteady periodic flows, although in laminar flow conditions. The tilting angle influences the flow dynamics also in the unsteady regimes and has a significant impact on mixing. The configuration characterized by the lower tilting angle, i.e., α = 10°, ensures a better global mixing performance than the one with the larger angle, i.e., α = 20°.
Stick-and-play metasurfaces for directional light outcoupling
Authors: Agata Kenichi , Murai Shunsuke , Tanaka Katsuhisa
Published: January 2021

Periodic arrays of metallic nanoparticles act as metasurfaces to control light at the interface. Although the combination of a variety of functional materials with metasurfaces should open a rich scientific research field, the application degree of freedom is limited severely by the fabrication process. We developed a metasurface sticker that can be stuck on any surface and gives control over in- and outcoupling of light. We demonstrate a photoluminescence outcoupling by placing a sticker on the luminescent layers: the emission pattern is modulated both spatially and spectrally in a way defined by the metasurface sticker. The sticker is useful for enhancing optical response from many different surfaces including those that are incompatible with the nanofabrication processes and should help the integration of metasurfaces into functional devices.
Design and characterization of a resonant microwave cavity as a diagnostic for ultracold plasmas
Authors: van Ninhuijs M. A. W. , Daamen K. A. , Beckers J. , Luiten O. J.
Published: January 2021

We present the design and commissioning of a resonant microwave cavity as a novel diagnostic for the study of ultracold plasmas. This diagnostic is based on the measurements of the shift in the resonance frequency of the cavity, induced by an ultracold plasma that is created from a laser-cooled gas inside. This method is simultaneously non-destructive, very fast (nanosecond temporal resolution), highly sensitive, and applicable to all ultracold plasmas. To create an ultracold plasma, we implement a compact magneto-optical trap based on a diffraction grating chip inside a 5 GHz resonant microwave cavity. We are able to laser cool and trap (7.25 ± 0.03) × 107 rubidium atoms inside the cavity, which are turned into an ultracold plasma by two-step pulsed (nanosecond or femtosecond) photo-ionization. We present a detailed characterization of the cavity, and we demonstrate how it can be used as a fast and sensitive probe to monitor the evolution of ultracold plasmas non-destructively. The temporal resolution of the diagnostic is determined by measuring the delayed frequency shift following femtosecond photo-ionization. We find a response time of 18 ± 2 ns, which agrees well with the value determined from the cavity quality factor and resonance frequency.
Empowering Indigenous agency through community-driven collaborative management to achieve effective conservation: Hawai‘i as an example
Authors: Winter Kawika B. , Vaughan Mehana Blaich , Kurashima Natalie , Giardina Christian , Quiocho Kalani , Chang Kevin , Akutagawa Malia , Beamer Kamanamaikalani , Berkes Fikret
Published: January 2021

Indigenous peoples and local communities (IPLCs) around the world are increasingly asserting ‘Indigenous agency’ to engage with government institutions and other partners to collaboratively steward ancestral Places. Case studies in Hawai‘i suggest that ‘community-driven collaborative management’ is a viable and robust pathway for IPLCs to lead in the design of a shared vision, achieve conservation targets, and engage government institutions and other organisations in caring for and governing biocultural resources and associated habitats. This paper articulates key forms of Indigenous agency embodied within Native Hawaiian culture, such as kua‘āina, hoa‘āina, and the interrelated values of aloha ‘āina, mālama ‘āina, and kia‘i ‘āina. We also examine how Hawai‘i might streamline the pathways to equitable and productive collaborative partnerships through: (1) a better understanding of laws protecting Indigenous rights and practices; (2) recognition of varied forms of Indigenous agency; and (3) more deliberate engagement in the meaningful sharing of power. We contend that these partnerships can directly achieve conservation and sustainability goals while transforming scientific fields such as conservation biology by redefining research practices and underlying norms and beliefs in Places stewarded by IPLCs. Further, collaborative management can de-escalate conflicts over access to, and stewardship of, resources by providing IPLCs avenues to address broader historical legacies of environmental and social injustice while restoring elements of self-governance. To these ends, we propose that government agencies proactively engage with IPLCs to expand the building of comprehensive collaborative management arrangements. Hawai‘i provides an example for how this can be achieved.
Prior activation state shapes the microglia response to antihuman TREM2 in a mouse model of Alzheimer’s disease
Authors: Ellwanger Daniel C. , Wang Shoutang , Brioschi Simone , Shao Zhifei , Green Lydia , Case Ryan , Yoo Daniel , Weishuhn Dawn , Rathanaswami Palaniswami , Bradley Jodi , Rao Sara , Cha Diana , Luan Peng , Sambashivan Shilpa , Gilfillan Susan , Hasson Samuel A. , Foltz Ian N. , van Lookeren Campagne Menno , Colonna Marco
Published: January 2021

Significance

Alzheimer’s disease (AD) is the most common dementia; no therapy halts its progression. AD pathology, including amyloid-β (Aβ) plaques, neurofibrillary tangles, and synapse loss, triggers microglial responses that modulate disease course. The TREM2 receptor promotes microglia responses to pathology and a variant,
TREM2
R47H
, impairs ligand binding and increases AD risk. Employing scRNA-seq, we asked: can an anti-TREM2 antibody, acting as a surrogate ligand, stimulate microglia in mice that accumulate Aβ and express either the common TREM2 variant (
TREM2
CV
) or
TREM2
R47H
? One systemic injection of anti-TREM2 restored microglia activation in
TREM2
R47H
mice but promoted limited activation in mice carrying
TREM2
CV
, which binds endogenous ligands. Thus, anti-TREM2 can strengthen microglial responses during AD, contingent on preexisting TREM2 engagement and basal activation.
Association of health-related quality of life with self-management and satisfaction of relationship with healthcare professionals in female patients with rheumatoid arthritis
Authors: Matsuura Emi , Origuchi Tomoki , Hamasaki Miwa
Published: January 2021

Objectives

We explored associations between health-related quality of life (QOL) with self-management and satisfaction with relationships with medical professionals among female rheumatoid arthritis (RA) patients.

Methods

Female RA outpatients completed anonymized self-reported questionnaires. Their confidence in self-managing different aspects of RA and satisfaction with relationships with medical professionals were assessed using a visual analog scale. Multiple regression analysis was performed to identify factors correlated with health-related QOL.

Results

Valid responses were received from 145 subjects. Mean PCS and MCS scores were 43.0 and 50.4, respectively, suggesting that female RA patients experience reduced QOL despite low disease activity, without perceiving difficulties in their daily lives. PCS scores correlated negatively with the modified Health Assessment Questionnaire (mHAQ) scores, and MCS scores correlated positively with stress self-management and patient–provider satisfaction, but negatively with mHAQ scores. PCS and MCS scores were not significantly influenced by demographic or clinical characteristics including age, disease duration, Steinbrocker stage (or class), or biologic use.

Conclusion

To improve health-related QOL in these patients, we must establish good patient–provider relationships and personalize strategies based on physical and mental conditions, enabling normal daily living. We should help achieve functional and social remission by improving their confidence in self-managing their disease.
Gradual exacerbation of knee flexion angle after total knee arthroplasty in patients with diabetes mellitus
Authors: Saiki Yoshitomo , Ojima Tomohiro , Kabata Tamon , Kubo Naoyuki , Hayashi Seigaku , Tsuchiya Hiroyuki
Published: January 2021

Objectives

This study aimed to investigate the effect of diabetes mellitus (DM) on knee extension/flexion angle and its early clinical course after total knee arthroplasty (TKA).

Methods

Patients who received TKA were retrospectively divided into two groups based on haemoglobinA1c level; the DM group (23 knees) and the control group (23 knees matched for baseline characteristics). The passive knee extension/flexion angle, gait speed and Japanese Orthopaedic Association (JOA) score were evaluated preoperatively and at 1, 6 and 12 months postoperatively.

Results

There was no significant difference in the passive knee flexion angle at 1 and 6 months postoperatively between the groups (p = .302, p = .160, respectively). The passive knee flexion angle was significantly lower at 12 months postoperatively in the DM group than the control group (p = .014). In the DM group, the passive knee flexion angle at 6 and 12 months significantly decreased compared with that at 1 month postoperatively (p = .021, p < .001, respectively). There were no significant differences in the knee extension angle, gait speed and JOA score between the groups.

Conclusion

Patients with DM are likely to experience passive knee flexion angle exacerbating from 1 to 6 months after TKA.
Spherically symmetric linear perturbations of electrically counterpoised dust
Authors: Aceña Andrés , Gentile de Austria Ivan
Published: January 2021

We consider spherically symmetric linear perturbations of static spherically symmetric spacetimes where the matter content is electrically counterpoised dust. We show that the evolution equation for the fluid perturbation implies that the fluid elements move with constant velocities. Therefore there are neither oscillations nor exponential departure from the background solution. We present an explicit example showing that the perturbation could lead to the formation of a black hole.
Crossing the phantom divide line as an effect of quantum transitions
Authors: Dimakis N , Paliathanasis Andronikos
Published: January 2021

We consider the chiral cosmological model consisting of two scalar fields minimally coupled to gravity. In the context of a Friedmann–Lemaître–Robertson–Walker (FLRW) spacetime, and for massless fields in the presence of a cosmological constant, we present the general solution of the field equations. The minisuperspace configuration that possesses maximal symmetry leads to scenarios which—depending on the admissible value of the parameters—correspond to a quintessence, quintom or phantom case. The canonical quantization of the model retrieves this distinction as different families of quantum states. The crossing of the phantom line is related to the existence of free or bound states for the Casimir operator of the symmetry algebra of the fields. The classical singularity, which is present in the quintessence solution, is also resolved at the quantum level.
Silicon-chip based electromagnetic vibration energy harvesters fabricated using wafer-level micro-casting technique
Authors: Han Ruofeng , Wang Nianying , Wang Jiachou , Gu Jiebin , Li Xinxin
Published: January 2021

This paper reports a silicon-chip based electromagnetic (EM) vibration energy harvester that is fabricated with a wafer-level micro-casting technique to form on-chip integrated 3D metal solenoids and magnet sliding channels. Many solenoids of 150-turn coil are simultaneously formed by filling molten ZnAl
x
alloy into the pre-micromachined solenoid moulds in one wafer within 7 min. After saw dicing to obtain the solenoid chips, a sliding permanent magnet for responding to environmental vibration is inserted into the pre-etched silicon channel inside the solenoid. Excited by external vibration, the magnet can slide in the channel to generate electricity. The size of the micro electro mechanical systems (MEMS) harvester chip is only 10.5 × 2.5 × 1.7 mm3. The experimental results show that the energy harvester can efficiently collect vibration energy in the environment. Under excited acceleration-amplitude of 49 m s−2 (i.e. 5 g) at the frequency of 24 Hz, the normalized power density (NPD) generated from the harvester reaches 12.38 μW cm−3 g−2. By comparing with reported non-MEMS wire-wound EM harvesters and on-chip piezoelectric/electrostatic ones, this silicon-chip based EM harvester exhibits much superior NPD.
Design and material for a patternable polysiloxane acrylate-based penetrating intracortical neural probe
Authors: Jung Woojin , Heo Chaejeong , Kim Jong Uk , Jeong Chanho , Ryu Hyewon , Park Byeonghak , Suh Minah , Kim Tae-il
Published: January 2021

Despite significant demand for penetrating intracortical neural probes (PINPs), challenges remain regarding their biocompatibility and stability due to the mechanical mismatch between brain tissue and PINPs. Here, we propose a promising UV patternable polymeric material for PINPs and a design criterion for optimizing the geometry of polymeric PINPs. UV-curable polysiloxane acrylate (PSA) shows remarkably low cytotoxicity in vitro, comparable to that of polyimide. Real-time two-photon imaging of CX3CR1-gfp-Tg mice reveals that a PSA microneedle shows a markedly low immune-responsive effect. The photo-patternability and modulus-tunability of PSA provide effective design capability, even for hierarchical structures. Also, we found a design criterion suggesting minimized scar that can penetrate the tissue surface, reducing both iatrogenic injury and mechanical mismatch while simultaneously dampening tissue micromotion. This damping behaviour of polymeric PINPS was shown by both experimental methods and finite element method simulation. Finally, we fabricated gold electrodes on PSA microneedles and successfully recorded local field potentials during seizure activity.
Frustrated tunneling ionization in strong circularly polarized two-color laser fields
Authors: Cao Chuanpeng , Li Min , Liang Jintai , Guo Keyu , Zhou Yueming , Lu Peixiang
Published: January 2021

We study the frustrated tunneling ionization (FTI) in counter-rotating and co-rotating circularly polarized two-color (CPTC) laser fields using a classical electron ensemble method. We find that the FTI probability depends sensitively on the relative helicity and the field amplitude ratio of the two-color laser fields. The FTI probability in the counter-rotating CPTC laser fields is three orders higher than that in the co-rotating fields. In the counter-rotating CPTC laser fields, the maximal FTI probability appears at the field amplitude ratio of ∼2.0, while in the co-rotating CPTC laser fields it appears at the ratio of ∼3.6. Tracing the electron trajectories, we find that recollision-assisted recapture plays an important role for the FTI in the CPTC laser fields. We further show that the angular momentum of the Rydberg state from the FTI events can be controlled by changing the field amplitude ratio of the counter-rotating CPTC laser fields, while it is nearly unchanged in the co-rotating CPTC laser fields.
Probing strong-field two-photon transitions through dynamic interference
Authors: Tóth Attila , Csehi András
Published: January 2021

We demonstrate how strong-field multiphoton transitions between dynamically shifted atomic levels can be traced in the energy spectra of emitted photoelectrons. Applying an ultrafast and intense laser pulse, two-photon Rabi oscillations are induced between two bound states of an atom. A third photon from the same pulse directly ionizes the atom, thus the emitted photoelectrons coherently probe the underlying dynamics. As the instantaneous energy of photoelectrons follows the pulse intensity envelope, modulated by the ac Stark shifts, electrons emitted with the same energy but at different times—at the rising and falling edge of the pulse—will interfere leading to pronounced dynamic interference pattern in the spectra. We investigate this phenomenon both numerically and analytically by developing a minimal three-state model that incorporates two-photon coupling and dynamically shifted atomic levels. On the example of atomic lithium (2s → → 4s → continuum) we show how the individual ac Stark shifts and the two-photon Rabi frequency are reflected through the asymmetry, shifting and splitting of the interference structure of the computed photopeaks.
Arbitrary power allocation for multiple beams using amplitude- and phase-coded metasurfaces
Authors: Chen Tian Yi , Li Yun Bo , Li He , Wang Hai Peng , Shen Jia Lin , Cui Tie Jun
Published: January 2021

Digital-coding metasurfaces provide a convenient method for designing metasurface-based functional devices. By delicately arranging the coding sequences, electromagnetic fields on the metasurfaces can be modulated for applications like wave-front engineering, amplitude controlling and polarization conversion. Theoretically, to fully realize arbitrary profiles for radiation patterns, both amplitude and phase modulations are needed for the responses of meta-atoms. Here, a method is proposed to generate multiple beams with arbitrary power intensity ratios using 2 bit amplitude and 2 bit phase digital-coding metasurfaces. A detailed process for designing the coding sequences is elaborated, and four-layer conformal square-loop meta-atoms are adopted to achieve 16 combinations of amplitude and phase codes. Two prototypes with dual beams of different radiation angles and power allocations are simulated, fabricated and measured. The experimental results match well with the predesigned expectations, which verifies the feasibility of the proposed method. It suggests that the digital-coding metasurface is a good candidate for multi-beam radiation pattern syntheses and is promising for various multi-functional telecommunication and radar applications.
Comprehensive influence of modulated and bias magnetic fields on an atomic magnetometer
Authors: Yan Yin  , Zhou Binquan , Yin Kaifeng , Tang Junjian , Ning Xiaolin , Han Bangcheng , Fang Jiancheng
Published: January 2021

The comprehensive influence of the amplitude and frequency of the modulated magnetic field and the magnitude of the bias magnetic field on the performance of an atomic magnetometer have been investigated. Under different magnetic fields, the combined action of the spin precession signal caused by a high-amplitude magnetic field and the influence of magnetic field on relaxation makes the time domain output signal and the amplitude of the first to fourth harmonics show different characteristics, which cannot be explained by the classical analytical calculation solution. By considering the influence of the magnetic field on the transverse relaxation, a more complete model is constructed to explain the phenomenon with a numerical solution, and the overall fit is 93.26%. Based on the single beam and magnetic field modulation scheme, a compact magnetometer is constructed for verification, with a volume of 56.7 cm3 and a sensitivity of 30 fT/Hz1/2.
Bulk nanomachining of cantilevers with Nb nanoSQUIDs based on nanobridge Josephson junctions
Authors: Faley M I , Bikulov T I , Bosboom V , Golubov A A , Dunin-Borkowski R E
Published: January 2021

Nanometer-scale superconducting quantum interference devices (nanoSQUIDs) were fabricated within a distance of 1 µm from the corners of 2

×

2

×

0.05 mm Si cantilevers that are intended for use in a scanning nanoSQUID microscope. The nanoSQUIDs contained Josephson junctions (JJs) in the form of Nb-based nanobridges, which had widths down to 10 nm and were patterned using hydrogen silsesquioxane negative resist. Numerical simulations of the superconducting current and the spatial distribution of the order parameter in the nanobridge JJs and the nanoSQUID, as well as the current–phase relationship in the nanobridge JJs, were performed according to Ginzburg–Landau equations on one-dimensional and two-dimensional grids. Bulk micromachining of the Si cantilever was performed using reactive ion etching with SF6 gas through masks of nLOF 2020 photoresist from the front side and a quartz shadow mask from the back side of the substrate. An etch rate of 6 µmmin−1 for Si was achieved for a power of 300 W of the inductively coupled SF6 plasma. The nanoSQUIDs exhibited non-hysteretic current–voltage characteristics on the cantilever. The estimated spin sensitivity of 48 µ
B (√Hz)−1 is sufficient for use of such a nanoSQUID as a magnetic field sensor for studying nanoscale objects, with a projected total distance to the object of below 100 nm.
Adaptable transfer-matrix method for fixed-energy finite-width beams
Authors: Bernal A , Avendaño J , Valencia-Torres R , García-Ravelo J
Published: January 2021

This work presents a novel methodology to analytically solve the stationary Schrödinger equation in presence of a couple of two-dimensional semi-infinite rectangular potential barriers, when the incident wave is a finite-width monoenergetic wave packet. Such methodology does not depend at all on the incident wavefront of the packet and is based on the transfer-matrix method, but unlike the latter, our transfer matrix is built partly in real space and partly in Fourier space. A spectrum of angular plane waves is used to represent the incident, reflected and transmitted beams. As a particular case, we study the transmission of Hermite-Gaussian wave packets through the barrier system. A detailed analysis of the transmission coefficient is carried out as a function of both the parameters of the incident beam (which in turn are directly related to the shape of the incident packet) and the parameters of the barriers. We also briefly discuss the behavior of the probability density of three transmitted beams.
A minimal model for household-based testing and tracing in epidemics
Authors: Huber Greg , Kamb Mason , Kawagoe Kyle , Li Lucy M , McGeever Aaron , Miller Jonathan , Veytsman Boris , Zigmond Dan
Published: January 2021

In a previous work (Huber et al. 2020 Phys. Biol.
17 065010), we discussed virus transmission dynamics modified by a uniform clustering of contacts in the population: close contacts within households and more distant contacts between households. In this paper, we discuss testing and tracing in such a stratified population. We propose a minimal tracing strategy consisting of random testing of the entire population plus full testing of the households of those persons found positive. We provide estimates of testing frequency for this strategy to work.
Passively mode-locked Yb-doped all-fiber oscillator using self-made strain-compensated semiconductor mirrors as saturable absorbers
Authors: Su Ning , Li Pingxue , Lin Nan , Yao Chuanfei , Xiong Wenhao , Dong Xueyan , Yang Min , Ma Xiaoyu
Published: January 2021

We report a linear-cavity mode-locked Yb-doped fiber laser using self-made semiconductor saturable absorber mirrors (SESAMs). The SESAMs are grown by means of metalorganic chemical vapor deposition, with a design of high modulation depth using strain-compensated multiple quantum wells. We choose two kinds of self-made SESAMs with different periods of top reflector in the linear cavity, and they can both be applied to stable mode-locking operation without damage. The output characteristics of the mode-locked oscillator indicate that SESAMs with high modulation depth are beneficial for mode-locked fiber lasers and the modulation depth can limit the pulse width of the output pulses.
Metasurface-assisted reflection-type terahertz beam splitter
Authors: Li Jiu-sheng
Published: January 2021

We designed and theoretically verified a reflection-type terahertz beam splitter based on a metasurface, which consisted of a two-dimensional S-shaped meta-atom periodic array and a metal bottom plate, separated by a polyimide layer. Using a predesigned coding sequence, the proposed structure was able to realize a number of scattered terahertz beams and the directional manipulation of the reflected terahertz wave beams in a terahertz frequency range (from 0.9 THz to 1.9 THz). The far-field scattering of the proposed design was simulated using CST Microwave Studio. The results verified that the designed device was able to reduce a radar cross-section larger than −10 dB in a frequency range from 0.9 THz to 1.4 THz and from 1.65 THz to 1.9 THz. This work provides new ideas for the design of terahertz devices.
First-principles calculations of K-shell x-ray absorption spectra for warm dense ammonia*
Authors: Li Zi , Li Wei-Jie , Wang Cong , Li Dafang , Kang Wei , He Xian-Tu , Zhang Ping
Published: January 2021

The x-ray absorption spectroscopy is a powerful tool for the detection of thermodynamic conditions and atomic structures on warm dense matter. Here, we perform first-principles molecular dynamics and x-ray absorption spectrum calculations for warm dense ammonia, which is one of the major constituents of Uranus and Neptune. The nitrogen K-shell x-ray absorption spectrum (XAS) is determined along the Hugoniot curve, and it is found that the XAS is a good indicator of the prevailing thermodynamic conditions. The atomic structures at these conditions are ascertained. Results indicate that the ammonia could dissociate to NH
x
(x = 0, 1, or 2) fragments and form nitrogen clusters, and the ratios of these products change with varying conditions. The contributions to the XAS from these products show quite different characteristics, inducing the significant change of XAS along the Hugoniot curve. Further model simulations imply that the distribution of the peak position of atomic XAS is the dominant factor affecting the total XAS.