bluuebunny/crossref_metadata_2025 huggingface dataset:
Atypical Brain Asymmetry in Human Situs Inversus: Gut Feeling or Real Evidence?
Authors: Vingerhoets Guy , Gerrits Robin , Verhelst Helena
Published: April 2021

The alignment of visceral and brain asymmetry observed in some vertebrate species raises the question of whether this association also exists in humans. While the visceral and brain systems may have developed asymmetry for different reasons, basic visceral left–right differentiation mechanisms could have been duplicated to establish brain asymmetry. We describe the main phenotypical anomalies and the general mechanism of left–right differentiation of vertebrate visceral and brain laterality. Next, we systematically review the available human studies that explored the prevalence of atypical behavioral and brain asymmetry in visceral situs anomalies, which almost exclusively involved participants with the mirrored visceral organization (situs inversus). The data show no direct link between human visceral and brain functional laterality as most participants with situs inversus show the typical population bias for handedness and brain functional asymmetry, although an increased prevalence of functional crowding may be present. At the same time, several independent studies present evidence for a possible relation between situs inversus and the gross morphological asymmetry of the brain torque with potential differences between subtypes of situs inversus with ciliary and non-ciliary etiologies.
Axisymmetric Finite Element Modelling of the Human Lens Complex under Cataract Surgery
Authors: Cardoso M. T. , Feijóo B. , Castro A. P. G. , Ribeiro F. J. , Fernandes P. R.
Published: April 2021

Cataract is a disease opacifying the crystalline, leading to a blurred vision and ultimately to blindness. With an aging population, the incidence of cataract is increasing, as well as the number of treatments. The solution available is its complete removal, followed by an implant of an intraocular lens (IOL). Although the post-operative complications on cataract surgeries have been decreasing in general, the bag-IOL complex dislocation is still an issue, probably being the most serious complication under this procedure. In this work, an axisymmetric Finite Element (FE) modelling strategy of the crystalline complex during the process of accommodation under cataract surgery is proposed. The goal was to understand the influence of biomechanical alterations promoted by the IOL on bag-IOL dislocation after surgery. An increase of force and stress in the zonules was verified in the pseudophakic eye compared to the complete eye, which could explain why zonules break years after surgery, leading to the bag-IOL dislocation. The axisymmetric FE model proposed in this work is innovative in this field, which still lacks detailed research, and can be an important complement for the clinical and biomechanical work on the crystalline complex.
CAKE: Compatible Authentication and Key Exchange Protocol for a Smart City in 5G Networks
Authors: Chuang Yun-Hsin , Tseng Yuh-Min
Published: April 2021

In a smart city, there are different types of entities, such as nature persons, IoT devices, and service providers, which have different computational limitations and storage limitations. Unfortunately, all of the existing authentication and key exchange (AKE) protocols are designed for either client–server or client–client authentication, including the ones designed for smart cities. In this paper, we present the idea of a compatible authentication and key exchange (CAKE) protocol which provides cross-species authentication. We propose the first CAKE protocol for a smart city that any two valid entities can authenticate with each other and create a secure session key without the help of any third party, while there is also no password table and no public key issuing problem. The entity can be a natural person having biometrics, an IoT device embedded with a physical unclonable function (PUF), or a service provider. Moreover, we extend the CAKE protocol to an anonymous CAKE (ACAKE) protocol, which provides natural persons an anonymous option to protect their privacy. In addition, both the proposed CAKE and ACAKE protocols can deal with the entity revocation problem. We define the framework and the security model of CAKE and ACAKE protocols. Under the security model, we formally prove that the proposed protocols are secure under the elliptic curve computational Diffie–Hellman (ECCDH) problem, the decisional bilinear Diffie–Hellman (DBDH) problem, and hash function assumptions. Comparisons with the related protocols are conducted to demonstrate the benefits of our protocols. Performance analysis is conducted and the experience results show that the proposed protocols are practical in a smart city.
High Area-Efficient Parallel Encoder with Compatible Architecture for 5G LDPC Codes
Authors: Zhu Yufei , Xing Zuocheng , Li Zerun , Zhang Yang , Hu Yifan
Published: April 2021

This paper presents a novel parallel quasi-cyclic low-density parity-check (QC-LDPC) encoding algorithm with low complexity, which is compatible with the 5th generation (5G) new radio (NR). Basing on the algorithm, we propose a high area-efficient parallel encoder with compatible architecture. The proposed encoder has the advantages of parallel encoding and pipelined operations. Furthermore, it is designed as a configurable encoding structure, which is fully compatible with different base graphs of 5G LDPC. Thus, the encoder architecture has flexible adaptability for various 5G LDPC codes. The proposed encoder was synthesized in a 65 nm CMOS technology. According to the encoder architecture, we implemented nine encoders for distributed lifting sizes of two base graphs. The eperimental results show that the encoder has high performance and significant area-efficiency, which is better than related prior art. This work includes a whole set of encoding algorithm and the compatible encoders, which are fully compatible with different base graphs of 5G LDPC codes. Therefore, it has more flexible adaptability for various 5G application scenarios.
Inter-Frame Based Interpolation for Top–Bottom Packed Frame of 3D Video
Authors: Van Duc Phan , Tin Phu Tran , Le Anh Vu , Nhan Nguyen Huu Khanh , Elara Mohan Rajesh
Published: April 2021

The frame-compatible packing for 3D contents is the feasible approach to archive the compatibility with the existing monocular broadcasting system. To perceive better 3D quality, the packed 3D frames are expanded to the full size at the decoder. In this paper, an interpolation technique enhancing and comparing the quality of enlarged halt vertical left and right stereo video in the top–bottom frame-compatible packing is presented. To this end, the appropriate interpolation modes from fourteen available modes for each row segment, which exploit the correlation between left and right stereoscopic as well as current and adjacent frames of individual view, are estimated at the encoder. Based on the information received from the encoder, at the decoder, the interpolation scheme can select the most appropriate available original data to find the missing values of to-be-discarded row segments. The proposed method outperformed than the state-of-the-art interpolation methods in terms of subjective visualization and numerical PSNRs and SSMI about 11%, with an execution time of about 12% comparisons.
Analogies between Logistic Equation and Relativistic Cosmology
Authors: Dussault Steve , Faraoni Valerio , Giusti Andrea
Published: April 2021

We develop several formal analogies between the logistic equation and the spatially homogeneous and isotropic relativistic cosmology described by the Einstein–Friedmann equations. These analogies produce an effective Lagrangian and Hamiltonian and new symmetries for the logistic equation.
Orbit Polynomial of Graphs versus Polynomial with Integer Coefficients
Authors: Ghorbani Modjtaba , Jalali-Rad Maryam , Dehmer Matthias
Published: April 2021

Suppose ai indicates the number of orbits of size i in graph G. A new counting polynomial, namely an orbit polynomial, is defined as OG(x) = ∑i aixi. Its modified version is obtained by subtracting the orbit polynomial from 1. In the present paper, we studied the conditions under which an integer polynomial can arise as an orbit polynomial of a graph. Additionally, we surveyed graphs with a small number of orbits and characterized several classes of graphs with respect to their orbit polynomials.
Applying Ateb–Gabor Filters to Biometric Imaging Problems
Authors: Nazarkevych Mariia , Kryvinska Natalia , Voznyi Yaroslav
Published: April 2021

This article presents a new method of image filtering based on a new kind of image processing transformation, particularly the wavelet-Ateb–Gabor transformation, that is a wider basis for Gabor functions. Ateb functions are symmetric functions. The developed type of filtering makes it possible to perform image transformation and to obtain better biometric image recognition results than traditional filters allow. These results are possible due to the construction of various forms and sizes of the curves of the developed functions. Further, the wavelet transformation of Gabor filtering is investigated, and the time spent by the system on the operation is substantiated. The filtration is based on the images taken from NIST Special Database 302, that is publicly available. The reliability of the proposed method of wavelet-Ateb–Gabor filtering is proved by calculating and comparing the values of peak signal-to-noise ratio (PSNR) and mean square error (MSE) between two biometric images, one of which is filtered by the developed filtration method, and the other by the Gabor filter. The time characteristics of this filtering process are studied as well.
Painlevé–Gullstrand form of the Lense–Thirring Spacetime
Authors: Baines Joshua , Berry Thomas , Simpson Alex , Visser Matt
Published: April 2021

The standard Lense–Thirring metric is a century-old slow-rotation large-distance approximation to the gravitational field outside a rotating massive body, depending only on the total mass and angular momentum of the source. Although it is not an exact solution to the vacuum Einstein equations, asymptotically the Lense–Thirring metric approaches the Kerr metric at large distances. Herein we shall discuss a specific variant of the standard Lense–Thirring metric, carefully chosen for simplicity, clarity, and various forms of improved mathematical and physical behaviour, (to be more carefully defined in the body of the article). We shall see that this Lense–Thirring variant can be viewed as arising from the linearization of a suitably chosen tetrad representing the Kerr spacetime. In particular, we shall construct an explicit unit-lapse Painlevé–Gullstrand variant of the Lense–Thirring spacetime, one that has flat spatial slices, a very simple and physically intuitive tetrad, and extremely simple curvature tensors. We shall verify that this variant of the Lense–Thirring spacetime is Petrov type I, (so it is not algebraically special), but nevertheless possesses some very straightforward timelike geodesics, (the “rain” geodesics). We shall also discuss on-axis and equatorial geodesics, ISCOs (innermost stable circular orbits) and circular photon orbits. Finally, we wrap up by discussing some astrophysically relevant estimates, and analyze what happens if we extrapolate down to small values of r; verifying that for sufficiently slow rotation we explicitly recover slowly rotating Schwarzschild geometry. This Lense–Thirring variant can be viewed, in its own right, as a “black hole mimic”, of direct interest to the observational astronomy community.
Identification of Novel Antiviral Compounds Targeting Entry of Hantaviruses
Authors: Mayor Jennifer , Torriani Giulia , Engler Olivier , Rothenberger Sylvia
Published: April 2021

Hemorrhagic fever viruses, among them orthohantaviruses, arenaviruses and filoviruses, are responsible for some of the most severe human diseases and represent a serious challenge for public health. The current limited therapeutic options and available vaccines make the development of novel efficacious antiviral agents an urgent need. Inhibiting viral attachment and entry is a promising strategy for the development of new treatments and to prevent all subsequent steps in virus infection. Here, we developed a fluorescence-based screening assay for the identification of new antivirals against hemorrhagic fever virus entry. We screened a phytochemical library containing 320 natural compounds using a validated VSV pseudotype platform bearing the glycoprotein of the virus of interest and encoding enhanced green fluorescent protein (EGFP). EGFP expression allows the quantitative detection of infection and the identification of compounds affecting viral entry. We identified several hits against four pseudoviruses for the orthohantaviruses Hantaan (HTNV) and Andes (ANDV), the filovirus Ebola (EBOV) and the arenavirus Lassa (LASV). Two selected inhibitors, emetine dihydrochloride and tetrandrine, were validated with infectious pathogenic HTNV in a BSL-3 laboratory. This study provides potential therapeutics against emerging virus infection, and highlights the importance of drug repurposing.
Virus Infection of Aspergillus fumigatus Compromises the Fungus in Intermicrobial Competition
Authors: Nazik Hasan , Kotta-Loizou Ioly , Sass Gabriele , Coutts Robert H. A. , Stevens David A.
Published: April 2021

Aspergillus and Pseudomonas compete in nature, and are the commonest bacterial and fungal pathogens in some clinical settings, such as the cystic fibrosis lung. Virus infections of fungi occur naturally. Effects on fungal physiology need delineation. A common reference Aspergillus fumigatus strain, long studied in two (of many) laboratories, was found infected with the AfuPmV-1 virus. One isolate was cured of virus, producing a virus-free strain. Virus from the infected strain was purified and used to re-infect three subcultures of the virus-free fungus, producing six fungal strains, otherwise isogenic. They were studied in intermicrobial competition with Pseudomonasaeruginosa. Pseudomonas culture filtrates inhibited forming or preformed Aspergillus biofilm from infected strains to a greater extent, also seen when Pseudomonas volatiles were assayed on Aspergillus. Purified iron-chelating Pseudomonas molecules, known inhibitors of Aspergillus biofilm, reproduced these differences. Iron, a stimulus of Aspergillus, enhanced the virus-free fungus, compared to infected. All infected fungal strains behaved similarly in assays. We show an important consequence of virus infection, a weakening in intermicrobial competition. Viral infection may affect the outcome of bacterial–fungal competition in nature and patients. We suggest that this occurs via alteration in fungal stress responses, the mechanism best delineated here is a result of virus-induced altered Aspergillus iron metabolism.
Zika Brazilian Cohorts (ZBC) Consortium: Protocol for an Individual Participant Data Meta-Analysis of Congenital Zika Syndrome after Maternal Exposure during Pregnancy
Authors: Alecrim Maria , Amorim Melania , Araújo Thalia , Brasil Patrícia , Brickley Elizabeth , Castilho Marcia , Coelho Bernadete , Cunha Antônio , Duarte Geraldo , Estofolete Cássia , Gurgel Ricardo , Herrero-Silva Juliana , Hofer Cristina , Lopes Aline , Martelli Celina , Melo Adriana , Miranda-Filho Demócrito , Montarroyos Ulisses , Moreira Maria , Mussi-Pinhata Marisa , Oliveira Consuelo , Passos Saulo , Prata-Barbosa Arnaldo , Santos Darci , Schuler-Faccini Lavínia , Silva Antônio , Siqueira Isadora , Sousa Patrícia , Turchi Marília , Ximenes Ricardo , Zara Ana ,   Zika Brazilian Cohorts Consortium (ZBC-Consortium)
Published: April 2021

Despite great advances in our knowledge of the consequences of Zika virus to human health, many questions remain unanswered, and results are often inconsistent. The small sample size of individual studies has limited inference about the spectrum of congenital Zika manifestations and the prognosis of affected children. The Brazilian Zika Cohorts Consortium addresses these limitations by bringing together and harmonizing epidemiological data from a series of prospective cohort studies of pregnant women with rash and of children with microcephaly and/or other manifestations of congenital Zika. The objective is to estimate the absolute risk of congenital Zika manifestations and to characterize the full spectrum and natural history of the manifestations of congenital Zika in children with and without microcephaly. This protocol describes the assembly of the Consortium and protocol for the Individual Participant Data Meta-analyses (IPD Meta-analyses). The findings will address knowledge gaps and inform public policies related to Zika virus. The large harmonized dataset and joint analyses will facilitate more precise estimates of the absolute risk of congenital Zika manifestations among Zika virus-infected pregnancies and more complete descriptions of its full spectrum, including rare manifestations. It will enable sensitivity analyses using different definitions of exposure and outcomes, and the investigation of the sources of heterogeneity between studies and regions.
New World Cactaceae Plants Harbor Diverse Geminiviruses
Authors: Fontenele Rafaela S. , Salywon Andrew M. , Majure Lucas C. , Cobb Ilaria N. , Bhaskara Amulya , Avalos-Calleros Jesús A. , Argüello-Astorga Gerardo R. , Schmidlin Kara , Khalifeh Anthony , Smith Kendal , Schreck Joshua , Lund Michael C. , Köhler Matias , Wojciechowski Martin F. , Hodgson Wendy C. , Puente-Martinez Raul , Van Doorslaer Koenraad , Kumari Safaa , Oyeniran Kehinde A. , Vernière Christian , Filloux Denis , Roumagnac Philippe , Lefeuvre Pierre , Ribeiro Simone G. , Kraberger Simona P. , Martin Darren P. , Varsani Arvind
Published: April 2021

The family Cactaceae comprises a diverse group of typically succulent plants that are native to the American continent but have been introduced to nearly all other continents, predominantly for ornamental purposes. Despite their economic, cultural, and ecological importance, very little research has been conducted on the viral community that infects them. We previously identified a highly divergent geminivirus that is the first known to infect cacti. Recent research efforts in non-cultivated and asymptomatic plants have shown that the diversity of this viral family has been under-sampled. As a consequence, little is known about the effects and interactions of geminiviruses in many plants, such as cacti. With the objective to expand knowledge on the diversity of geminiviruses infecting cacti, we used previously acquired high-throughput sequencing results to search for viral sequences using BLASTx against a viral RefSeq protein database. We identified two additional sequences with similarity to geminiviruses, for which we designed abutting primers and recovered full-length genomes. From 42 cacti and five scale insects, we derived 42 complete genome sequences of a novel geminivirus species that we have tentatively named Opuntia virus 2 (OpV2) and 32 genomes of an Opuntia-infecting becurtovirus (which is a new strain of the spinach curly top Arizona virus species). Interspecies recombination analysis of the OpV2 group revealed several recombinant regions, in some cases spanning half of the genome. Phylogenetic analysis demonstrated that OpV2 is a novel geminivirus more closely related to viruses of the genus Curtovirus, which was further supported by the detection of three recombination events between curtoviruses and OpV2. Both OpV2 and Opuntia becurtoviruses were identified in mixed infections, which also included the previously characterized Opuntia virus 1. Viral quantification of the co-infected cactus plants compared with single infections did not show any clear trend in viral dynamics that might be associated with the mixed infections. Using experimental Rhizobium-mediated inoculations, we found that the initial accumulation of OpV2 is facilitated by co-infection with OpV1. This study shows that the diversity of geminiviruses that infect cacti is under-sampled and that cacti harbor diverse geminiviruses. The detection of the Opuntia becurtoviruses suggests spill-over events between viruses of cultivated species and native vegetation. The threat this poses to cacti needs to be further investigated.
Long-COVID and Post-COVID Health Complications: An Up-to-Date Review on Clinical Conditions and Their Possible Molecular Mechanisms
Authors: Silva Andrade Bruno , Siqueira Sérgio , de Assis Soares Wagner Rodrigues , de Souza Rangel Fernanda , Santos Naiane Oliveira , dos Santos Freitas Andria , Ribeiro da Silveira Priscila , Tiwari Sandeep , Alzahrani Khalid J , Góes-Neto Aristóteles , Azevedo Vasco , Ghosh Preetam , Barh Debmalya
Published: April 2021

The COVID-19 pandemic has infected millions worldwide, leaving a global burden for long-term care of COVID-19 survivors. It is thus imperative to study post-COVID (i.e., short-term) and long-COVID (i.e., long-term) effects, specifically as local and systemic pathophysiological outcomes of other coronavirus-related diseases (such as Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS)) were well-cataloged. We conducted a comprehensive review of adverse post-COVID health outcomes and potential long-COVID effects. We observed that such adverse outcomes were not localized. Rather, they affected different human systems, including: (i) immune system (e.g., Guillain–Barré syndrome, rheumatoid arthritis, pediatric inflammatory multisystem syndromes such as Kawasaki disease), (ii) hematological system (vascular hemostasis, blood coagulation), (iii) pulmonary system (respiratory failure, pulmonary thromboembolism, pulmonary embolism, pneumonia, pulmonary vascular damage, pulmonary fibrosis), (iv) cardiovascular system (myocardial hypertrophy, coronary artery atherosclerosis, focal myocardial fibrosis, acute myocardial infarction, cardiac hypertrophy), (v) gastrointestinal, hepatic, and renal systems (diarrhea, nausea/vomiting, abdominal pain, anorexia, acid reflux, gastrointestinal hemorrhage, lack of appetite/constipation), (vi) skeletomuscular system (immune-mediated skin diseases, psoriasis, lupus), (vii) nervous system (loss of taste/smell/hearing, headaches, spasms, convulsions, confusion, visual impairment, nerve pain, dizziness, impaired consciousness, nausea/vomiting, hemiplegia, ataxia, stroke, cerebral hemorrhage), (viii) mental health (stress, depression and anxiety). We additionally hypothesized mechanisms of action by investigating possible molecular mechanisms associated with these disease outcomes/symptoms. Overall, the COVID-19 pathology is still characterized by cytokine storm that results to endothelial inflammation, microvascular thrombosis, and multiple organ failures.
Virulence and Infectivity of UC, MD, and L Strains of Infectious Hematopoietic Necrosis Virus (IHNV) in Four Populations of Columbia River Basin Chinook Salmon
Authors: Hernandez Daniel G. , Brown William , Naish Kerry A. , Kurath Gael
Published: April 2021

Infectious Hematopoietic Necrosis Virus (IHNV) infects juvenile salmonid fish in conservation hatcheries and aquaculture facilities, and in some cases, causes lethal disease. This study assesses intra-specific variation in the IHNV susceptibility of Chinook salmon (Oncorhynchus tshawytscha) in the Columbia River Basin (CRB), in the northwestern United States. The virulence and infectivity of IHNV strains from three divergent virus genogroups are measured in four Chinook salmon populations, including spring-run and fall-run fish from the lower or upper regions of the CRB. Following controlled laboratory exposures, our results show that the positive control L strain had significantly higher virulence, and the UC and MD strains that predominate in the CRB had equivalently low virulence, consistent with field observations. By several experimental measures, there was little variation in host susceptibility to infection or disease. However, a small number of exceptions suggested that the lower CRB spring-run Chinook salmon population may be less susceptible than other populations tested. The UC and MD viruses did not differ in infectivity, indicating that the observed asymmetric field prevalence in which IHNV detected in CRB Chinook salmon is 83% UC and 17% MD is not due to the UC virus being more infectious. Overall, we report little intra-species variation in CRB Chinook salmon susceptibility to UC or MD IHNV infection or disease, and suggest that other factors may instead influence the ecology of IHNV in the CRB.
Special Issue “Arenaviruses 2020”
Authors: Lukashevich Igor S. , Torre Juan Carlos de la
Published: April 2021

Rodent-borne arenaviruses have been traditionally predominantly associated with certain muroid species from Mastomys/Praomys genera (African arenaviruses) or with species that belong to murid subfamily Cricetidae (New World arenaviruses) [...]
Bombyx mori Pupae Efficiently Produce Recombinant AAV2/HBoV1 Vectors with a Bombyx mori Nuclear Polyhedrosis Virus Expression System
Authors: Yu Qian , Chang Pengfei , Liu Xiaoxuan , Lü Peng , Tang Qi , Guo Zhongjian , Qiu Jianming , Chen Keping , Yao Qin
Published: April 2021

Recombinant adeno-associated virus (AAV) vectors have broad application prospects in the field of gene therapy. The establishment of low-cost and large-scale manufacturing is now the general agenda for industry. The baculovirus-insect cell/larva expression system has great potential for these applications due to its scalability and predictable biosafety. To establish a more efficient production system, Bombyx mori pupae were used as a new platform and infected with recombinant Bombyx mori nuclear polyhedrosis virus (BmNPV). The production of a chimeric recombinant adeno-associated virus (rAAV) serotype 2/human bocavirus type-1 (HBoV1) vector was used to evaluate the efficiency of this new baculovirus expression vector (BEV)–insect expression system. For this purpose, we constructed two recombinant BmNPVs, which were named rBmNPV/AAV2Rep-HBoV1Cap and rBmNPV/AAV2ITR-eGFP. The yields of rAAV2/HBoV1 derived from the rBmNPV/AAV2Rep-HBoV1Cap and rBmNPV/AAV2ITR-eGFP co-infected BmN cells exceeded 2 × 104 vector genomes (VG) per cell. The rBmNPV/AAV2Rep-HBoV1Cap and rBmNPV/AAV2ITR-eGFP can express stably for at least five passages. Significantly, rAAV2/HBoV1 could be efficiently generated from BmNPV-infected silkworm larvae and pupae at average yields of 2.52 × 1012 VG/larva and 4.6 × 1012 VG/pupa, respectively. However, the vectors produced from the larvae and pupae had a high percentage of empty particles, which suggests that further optimization is required for this platform in the future. Our work shows that silkworm pupae, as an efficient bioreactor, have great potential for application in the production of gene therapy vectors.
Facilitators and Barriers to Take Up Clinician-Collected and Self-Collected HPV Tests among Chinese Men Who Have Sex with Men
Authors: Wang Zixin , Fang Yuan , Wong Ngai Sze , Ip Mary , Guo Xin , Wong Samuel Yeung Shan
Published: April 2021

Regular tests for human papillomavirus (HPV) and early treatment could represent an important strategy for preventing anal cancers among men who have sex with men (MSM). This study investigated facilitators and barriers to take up clinician-collected and self-collected HPV tests among Chinese MSM. This study was based on the baseline sample of a longitudinal study promoting HPV vaccination among 350 Chinese MSM who had never received an HPV vaccination. The baseline survey was conducted from August 2019 to April 2020. The prevalence of any HPV tests uptake in lifetime was 19.1%; 4.9% had HPV infection in anus, genital, oral cavity, and other places. Among the participants, 20% and 76.8% intended to take up self-financed and free clinician-collected HPV tests, and 76.8% intended to use free self-collected HPV tests. After adjusting for significant background characteristics, perceived risk of HPV infection, and perceived benefits, barriers, cue to action, and self-efficacy related to HPV tests in general and/or specific to self-collected HPV tests were associated with behavioral intention to take up free clinician-collected and/or self-collected HPV tests. Less than 20% of Chinese MSM reported HPV tests uptake. Modifying perceptions related to HPV tests may be useful to increase HPV tests coverage in this group.
Analysis of Thrombotic Adverse Reactions of COVID-19 AstraZeneca Vaccine Reported to EudraVigilance Database
Authors: Tobaiqy Mansour , Elkout Hajer , MacLure Katie
Published: April 2021

The development of safe, effective, affordable vaccines against COVID-19 remains the cornerstone to mitigating this pandemic. Early in December 2020, multiple research groups had designed potential vaccines. From 11 March 2021, several European countries temporarily suspended the use of the Oxford–AstraZeneca vaccine amid reports of blood clot events and the death of a vaccinated person, despite the European Medicines Agency (EMA) and the World Health Organization’s assurance that there was no indication that vaccination was linked. This study aimed to identify and analyse the thrombotic adverse reactions associated with the Oxford–AstraZeneca vaccine. This was a retrospective descriptive study using spontaneous reports submitted to the EudraVigilance database in the period from 17 February to 12 March 2021. There were 54,571 adverse reaction reports, of which 28 were associated with thrombotic adverse reactions. Three fatalities were related to pulmonary embolism; one fatality to thrombosis. With 17 million people having had the AstraZeneca vaccine, these are extremely rare events The EMA’s Pharmacovigilance Risk Assessment Committee (18 March 2021) concluded that the vaccine was safe, effective and the benefits outweighed the risks. Conducting further analyses based on more detailed thrombotic adverse event reports, including patients’ characteristics and comorbidities, may enable assessment of the causality with higher specificity.
Development of a Vaccine against SARS-CoV-2 Based on the Receptor-Binding Domain Displayed on Virus-Like Particles
Authors: Zha Lisha , Chang Xinyue , Zhao Hongxin , Mohsen Mona O. , Hong Liang , Zhou Yuhang , Chen Hongquan , Liu Xuelan , Zhang Jie , Li Dong , Wu Ke , Martina Byron , Wang Junfeng , Vogel Monique , Bachmann Martin F.
Published: April 2021

The ongoing coronavirus disease (COVID-19) pandemic is caused by a new coronavirus (severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2)) first reported in Wuhan City, China. From there, it has been rapidly spreading to many cities inside and outside China. Nowadays, more than 110 million cases with deaths surpassing 2 million have been recorded worldwide, thus representing a major health and economic issues. Rapid development of a protective vaccine against COVID-19 is therefore of paramount importance. Here, we demonstrated that the recombinantly expressed receptor-binding domain (RBD) of the spike protein can be coupled to immunologically optimized virus-like particles derived from cucumber mosaic virus (CuMVTT). The RBD displayed CuMVTT bound to ACE2, the viral receptor, demonstrating proper folding of RBD. Furthermore, a highly repetitive display of the RBD on CuMVTT resulted in a vaccine candidate that induced high levels of specific antibodies in mice, which were able to block binding of the spike protein to ACE2 and potently neutralize SARS-CoV-2 virus in vitro.
MMR Vaccine Attitude and Uptake Research in the United Kingdom: A Critical Review
Authors: Torracinta Louis , Tanner Rachel , Vanderslott Samantha
Published: April 2021

This review critically assesses the body of research about Measles-Mumps-and-Rubella (MMR) vaccine attitudes and uptake in the United Kingdom (UK) over the past 10 years. We searched PubMed and Scopus, with terms aimed at capturing relevant literature on attitudes about, and uptake of, the MMR vaccine. Two researchers screened for abstract eligibility and after de-duplication 934 studies were selected. After screening, 40 references were included for full-text review and thematic synthesis by three researchers. We were interested in the methodologies employed and grouped findings by whether studies concerned: (1) Uptake and Demographics; (2) Beliefs and Attitudes; (3) Healthcare Worker Focus; (4) Experimental and Psychometric Intervention; and (5) Mixed Methods. We identified group and individual level determinants for attitudes, operating directly and indirectly, which influence vaccine uptake. We found that access issues, often ignored within the public “anti-vax” debate, remain highly pertinent. Finally, a consistent theme was the effect of misinformation or lack of knowledge and trust in healthcare, often stemming from the Wakefield controversy. Future immunisation campaigns for children, including for COVID-19, should consider both access and attitudinal aspects of vaccination, and incorporate a range of methodologies to assess progress, taking into account socio-economic variables and the needs of disadvantaged groups.
AP205 VLPs Based on Dimerized Capsid Proteins Accommodate RBM Domain of SARS-CoV-2 and Serve as an Attractive Vaccine Candidate
Authors: Liu Xuelan , Chang Xinyue , Rothen Dominik , Derveni Mariliza , Krenger Pascal , Roongta Salony , Wright Edward , Vogel Monique , Tars Kaspars , Mohsen Mona O. , Bachmann Martin F.
Published: April 2021

COVID-19 is a novel disease caused by SARS-CoV-2 which has conquered the world rapidly resulting in a pandemic that massively impacts our health, social activities, and economy. It is likely that vaccination is the only way to form “herd immunity” and restore the world to normal. Here we developed a vaccine candidate for COVID-19 based on the virus-like particle AP205 displaying the spike receptor binding motif (RBM), which is the major target of neutralizing antibodies in convalescent patients. To this end, we genetically fused the RBM domain of SARS-CoV-2 to the C terminus of AP205 of dimerized capsid proteins. The fused VLPs were expressed in E. coli, which resulted in insoluble aggregates. These aggregates were denatured in 8 M urea followed by refolding, which reconstituted VLP formation as confirmed by electron microscopy analysis. Importantly, immunized mice were able to generate high levels of IgG antibodies recognizing eukaryotically expressed receptor binding domain (RBD) as well as spike protein of SARS-CoV-2. Furthermore, induced antibodies were able to neutralize SARS-CoV-2/ABS/NL20. Additionally, this vaccine candidate has the potential to be produced at large scale for immunization programs.
Introduction of Cysteines in the Stalk Domain of Recombinant Influenza Virus N1 Neuraminidase Enhances Protein Stability and Immunogenicity in Mice
Authors: Strohmeier Shirin , Carreño Juan Manuel , Brito Ruhi Nichalle , Krammer Florian
Published: April 2021

Influenza virus surface glycoproteins represent the main targets of the immune system during infection and vaccination. Current influenza virus vaccines rely mostly on the hemagglutinin, requiring a close match between the vaccine and circulating strains. Recently, the neuraminidase (NA) has become an attractive target; however low immunogenicity and stability in vaccine preparations remain an obstacles. Here, we took advantage of the hypervariable stalk domain of the NA to introduce cysteines at different positions and to produce more stable multimeric forms of the protein. We generated 11 N1 constructs and characterized the proteins by performing sodium dodecyl sulfate polyacrylamide gel electrophoresis and by testing their enzymatic activity and representation of antigenic epitopes. Moreover, we evaluated their potential to induce a protective immune response in vivo and characterized the polyclonal antibody responses of immunized mice. We observed that the introduction of cysteines at certain positions led to the formation of stable N1 dimers, which are capable of inducing a strong antibody response characterized by neuraminidase inhibiting activity and protection of mice from high dose viral challenge. Overall, our results provide evidence for the feasibility of introducing stalk modifications to enhance the stability and immunogenicity of NA-based recombinant antigens.
Retrospective Analysis of Water Management in Amsterdam, The Netherlands
Authors: Peters Sannah , Ouboter Maarten , Lugt Kees van der , Koop Stef , Leeuwen Kees van
Published: April 2021

The capital of The Netherlands, Amsterdam, is home to more than 800,000 people. Developments in water safety, water quality, and robust water infrastructure transitioned Amsterdam into an attractive, economically healthy, and safe city that scores highly in the field of water management. However, investments need to be continued to meet future challenges. Many other cities in the world have just started their transition to become water-wise. For those cities, it is important to assess current water management and governance practices, in order to set their priorities and to gain knowledge from the experiences of more advanced cities such as Amsterdam. We investigate how Amsterdam’s water management and governance developed historically and how these lessons can be used to further improve water management in Amsterdam and other cities. This retrospective analysis starts at 1672 and applies the City Blueprint Approach as a baseline water management assessment. It shows that developments in water infrastructure and water management have often been reactive in response to various crises. International knowledge exchange, implementation of integrated water resources management, and long-term planning improved the city considerably. We conclude that experiences from the past can be used to meet present and future challenges in many cities across the globe.
Trial of Chemical Composition Estimation Related to Submarine Volcano Activity Using Discolored Seawater Color Data Obtained from GCOM-C SGLI. A Case Study of Nishinoshima Island, Japan, in 2020
Authors: Sakuno Yuji
Published: April 2021

This study aims to develop the relational equation between the color and chemical composition of discolored seawater around a submarine volcano, and to examine its relation to the volcanic activity at Nishinoshima Island, Japan, in 2020, using the model applied by atmospheric corrected reflectance 8 day composite of GCOM-C SGLI. To achieve these objectives, the relational equation between the RGB value of the discolored seawater in the submarine volcano and the chemical composition summarized in past studies was derived using the XYZ colorimetric system. Additionally, the relationship between the volcanic activity of the island in 2020 and the chemical composition was compared in chronological order using the GCOM-C SGLI data. The following findings were obtained. First, a significant correlation was observed between the seawater color (x) calculated by the XYZ colorimetric system and the chemical composition such as (Fe + Al)/Si. Second, the distribution of (Fe + Al)/Si in the island, estimated from GCOM-C SGLI data, fluctuated significantly just before the volcanic activity became active (approximately one month prior). These results suggest that the chemical composition estimation of discolored seawater using SGLI data may be a powerful tool in predicting submarine volcanic activity.
Water ‘Apartheid’ and the Significance of Human Rights Principles of Affirmative Action in South Africa
Authors: Jegede Ademola , Shikwambane Pumzile
Published: April 2021

Water is an essential necessity for human beings; however, South Africa has a long history of inequalities dating back to apartheid politics and legislation which denied access to water to disadvantaged black populations mostly residing in rural areas. Although apartheid has officially ended, whether the lack of access to water by such populations who still cannot afford it exists and aligns with international human rights principles of equality and non-discrimination merits an examination. To redress the injustices of the apartheid regime, the right to have access to sufficient water is entrenched in section 27(1)(b) of the 1996 South African Constitution. In addition to embracing equality and non-discrimination, the Constitution informs other instruments and measures such as free basic water policy and pre-paid meters meant to ensure access to water. However, the plight of these populations persists in post-apartheid South Africa, but it is rarely a subject of academic scrutiny how the notion of affirmative action as grounded in the principles of equality and non-discrimination under human rights law can be deployed as a response. Using a doctrinal research approach, this article argues that the continuing struggle of disadvantaged communities with access to water does not only constitute water apartheid, it negates the human rights principles of equality and non-discrimination. The principle of affirmative action is useful in responding to inadequate access to sufficient water by disadvantaged populations in post-apartheid South Africa.
Land Use and Land Cover Change Assessment in the Context of Flood Hazard in Lagos State, Nigeria
Authors: Idowu Dorcas , Zhou Wendy
Published: April 2021

Incessant flooding is a major hazard in Lagos State, Nigeria, occurring concurrently with increased urbanization and urban expansion rate. Consequently, there is a need for an assessment of Land Use and Land Cover (LULC) changes over time in the context of flood hazard mapping to evaluate the possible causes of flood increment in the State. Four major land cover types (water, wetland, vegetation, and developed) were mapped and analyzed over 35 years in the study area. We introduced a map-matrix-based, post-classification LULC change detection method to estimate multi-year land cover changes between 1986 and 2000, 2000 and 2016, 2016 and 2020, and 1986 and 2020. Seven criteria were identified as potential causative factors responsible for the increasing flood hazards in the study area. Their weights were estimated using a combined (hybrid) Analytical Hierarchy Process (AHP) and Shannon Entropy weighting method. The resulting flood hazard categories were very high, high, moderate, low, and very low hazard levels. Analysis of the LULC change in the context of flood hazard suggests that most changes in LULC result in the conversion of wetland areas into developed areas and unplanned development in very high to moderate flood hazard zones. There was a 69% decrease in wetland and 94% increase in the developed area during the 35 years. While wetland was a primary land cover type in 1986, it became the least land cover type in 2020. These LULC changes could be responsible for the rise in flooding in the State.
Analytical Models of Velocity, Reynolds Stress and Turbulence Intensity in Ice-Covered Channels
Authors: Zhang Jiao , Wang Wen , Li Zhanbin , Li Qian , Zhong Ya , Xia Zhaohui , Qiu Hunan
Published: April 2021

Ice cover in an open channel can influence the flow structure, such as the flow velocity, Reynolds stress and turbulence intensity. This study analyzes the vertical distributions of velocity, Reynolds stress and turbulence intensity in fully and partially ice-covered channels by theoretical methods and laboratory experiments. According to the experimental data, the vertical profile of longitudinal velocities follows an approximately symmetry form. Different from the open channel flow, the maximum value of longitudinal velocity occurs near the middle of the water depth, which is close to the channel bed with a smoother boundary roughness compared to the ice cover. The measured Reynolds stress has a linear distribution along the vertical axis, and the vertical distribution of measured turbulence intensity follows an exponential law. Theoretically, a two-power-law function is presented to obtain the analytical formula of the longitudinal velocity. In addition, the vertical profile of Reynolds stress is obtained by the simplified momentum equation and the vertical profile of turbulence intensity is investigated by an improved exponential model. The predicted data from the analytical models agree well with the experimental ones, thereby confirming that the analytical models are feasible to predict the vertical distribution of velocity, Reynolds stress and turbulence intensity in ice-covered channels. The proposed models can offer an important theoretical reference for future study about the sediment transport and contaminant dispersion in ice-covered channels.
Selecting Suitable MODFLOW Packages to Model Pond–Groundwater Relations Using a Regional Model
Authors: Serrano-Hidalgo Carmen , Guardiola-Albert Carolina , Heredia Javier , Elorza Tenreiro Francisco Javier , Naranjo-Fernández Nuria
Published: April 2021

In large-scale regional models, used for the management of underground resources, it is quite common to find that relationships between the regional aquifer and small wetlands are not included. These models do not consider this connection because of the small amount of water involved, but they should consider the potential for significant ecological impacts if the groundwater resources in the ecosystems associated with these wetlands are mismanaged. The main objective of this work is to investigate the possibilities offered by MODFLOW LGR-V2 to represent (at small scale) the Santa Olalla pond, located in the Doñana Natural Park (South of Spain), and its relationship with the Almonte-Marismas regional aquifer. As a secondary objective, we propose to investigate the advantages and disadvantages that DRAIN, RIVER and LAKE MODFLOW packages offer within the MODFLOW LGR-V2 discretizations. The drain boundary condition with a coarse discretization implemented through ModelMuse allows the most adequate performance of the groundwater levels in the environment of the pond. However, when using lake boundary condition, the use of the MODFLOW LGR-V2 version is particularly useful. The present work also gives some guidelines to employ these packages with the MODFLOW graphical user’s interface, ModelMuse 4.2.
Evaluating the Collaborative Security of Water–Energy–Food in China on the Basis of Symbiotic System Theory
Authors: Li Xiao , Liu Cuishan , Wang Guoqing , Bao Zhenxin , Diao Yanfang , Liu Jing
Published: April 2021

Water, energy, and food are essential resources for humanity. The growing shortages of these resources and serious deterioration of river environments are having a big impact on the sustainable development of the economy and society in China. Water, energy, and food support human life and yet coexist in different ways, and therefore it is critical to find a way for all three key elements to be secured in order to support high standards of sustainable development in China. We used the criteria of stability, coordination, and sustainability of symbiotic systems to select 33 indexes that were then used to establish an index system. The weight of index was determined by using the entropy weight method combined with Analytic Hierarchy Process. The fuzzy comprehensive evaluation method was used to calculate the collaborative security index, which was the basis of our evaluation of the collaborative water–energy–food security of China in time and space. The results show that North China and Northwest China are at high water–food–energy security risk, while East, Central, and South China are at moderate risk. With the exception of Southwest China and South China, risk in most parts of the country has risen over the past decades, while it has fallen in Shandong, Henan, Sichuan, and Yunnan provinces.