bluuebunny/crossref_metadata_2025 huggingface dataset:
A Class of Fourth-Order Symmetrical Kirchhoff Type Systems
Authors: Wu Yong , Taarabti Said , El Allali Zakaria , Ben Hadddouch Khalil , Zuo Jiabin
Published: August 2022

This paper deals with the existence and multiplicity of solutions for a perturbed nonlocal fourth-order class of p(·)&q(·)-Kirchhoff elliptic systems under Navier boundary conditions. By using the variational method and Ricceri’s critical point theorem, we can find a proper conditions to ensure that the perturbed fourth-order of (p(x),q(x))-Kirchhoff systems has at least three weak solutions. We have extended and improved some recent results. The complexity of the combination of variable exponent theory and fourth-order Kirchhoff systems makes the results of this work novel and new contribution. Finally, a very concrete example is given to illustrate the applications of our results.
Dynamic Response Analysis of an Offshore Converter Platform with Valve Towers under Seismic Excitation
Authors: Sun Zhenzhou , Zhao Shengxiao , Bi Chunwei , Chen Qiupan , Huang Shanshan , Chen Jiefeng
Published: August 2022

Converter valves are the core equipment of offshore wind power structures. However, they are highly vulnerable to vibration under strong earthquakes, which will affect normal operation of the offshore wind farm. Converter station is an axisymmetric structure with obvious asymmetry in its internal configuration of the superstructure. This study aimed to analyze the dynamic response of a supported converter valve in an offshore converter station under seismic excitation. The coupling model of the supported valve tower group and the converter station were established, and the distribution law of the valve tower dynamic response and foundation settlement were investigated. The dynamic response effect of the modal truncation, valve tower stiffness, and basic size on different areas and foundations of the valve towers were studied. The findings were as follows: (i) the effect of local vibration of the valve tower should not be simplified by using equivalent mass and node condensation; (ii) the structure–equipment coupling analysis method should be used to review the structural design scheme of the offshore converter station in the intensity VII region; (iii) the vertical higher-order modes should be considered during the vibration response calculation and its participation ratio in mass should not be lower than 90%; (iv) the frequency range that minimizes the vibration response is the characteristic frequency range of horizontal vibration, while the best vibration suppression effect cannot be obtained in both the horizontal and vertical directions; and (v) the stiffness of the valve tower itself should be adjusted and different stiffness designs of the valve tower in different positions should be adopted to realize effective vibration response control.
Algebraic Theory of Patterns as Generalized Symmetries
Authors: Rupe Adam , Crutchfield James P.
Published: August 2022

We generalize the exact predictive regularity of symmetry groups to give an algebraic theory of patterns, building from a core principle of future equivalence. For topological patterns in fully-discrete one-dimensional systems, future equivalence uniquely specifies a minimal semiautomaton. We demonstrate how the latter and its semigroup algebra generalizes translation symmetry to partial and hidden symmetries. This generalization is not as straightforward as previously considered. Here, though, we clarify the underlying challenges. A stochastic form of future equivalence, known as predictive equivalence, captures distinct statistical patterns supported on topological patterns. Finally, we show how local versions of future equivalence can be used to capture patterns in spacetime. As common when moving to higher dimensions, there is not a unique local approach, and we detail two local representations that capture different aspects of spacetime patterns. A previously developed local spacetime variant of future equivalence captures patterns as generalized symmetries in higher dimensions, but we show that this representation is not a faithful generator of its spacetime patterns. This motivates us to introduce a local representation that is a faithful generator, but we demonstrate that it no longer captures generalized spacetime symmetries. Taken altogether, building on future equivalence, the theory defines and quantifies patterns present in a wide range of classical field theories.
Lorentz Transformation in Maxwell Equations for Slowly Moving Media
Authors: Sheng Xin-Li , Li Yang , Pu Shi , Wang Qun
Published: August 2022

We use the method of field decomposition, a widely used technique in relativistic magnetohydrodynamics, to study the small velocity approximation (SVA) of the Lorentz transformation in Maxwell equations for slowly moving media. The “deformed” Maxwell equations derived using SVA in the lab frame can be put into the conventional form of Maxwell equations in the medium’s co-moving frame. Our results show that the Lorentz transformation in the SVA of up to O(v/c) (v is the speed of the medium and c is the speed of light in a vacuum) is essential to derive these equations: the time and charge density must also change when transforming to a different frame, even in the SVA, not just the position and current density, as in the Galilean transformation. This marks the essential difference between the Lorentz transformation and the Galilean one. We show that the integral forms of Faraday and Ampere equations for slowly moving surfaces are consistent with Maxwell equations. We also present Faraday equation in the covariant integral form, in which the electromotive force can be defined as a Lorentz scalar that is independent of the observer’s frame. No evidence exists to support an extension or modification of Maxwell equations.
The Effect of Linear Operators in Periodical Solutions of Ordinary Differential Equations
Authors: Soradi-Zeid Samaneh , Mesrizadeh Mehdi , Cattani Carlo
Published: August 2022

In the present paper, we investigate the influence of the choice of continuous linear operator for obtaining the approximate periodic solutions of ordinary second-order differential equations. In most of these problems, the periods are unknown, and the determination of these periods and periodic solutions is a difficult issue. So, a new computational method is proposed based on the symmetric operator, namely the reproducing kernel Hilbert space (RKHS) method to obtain the interval of these solutions. This operator, as a consequence of the symmetric inner product, is a symmetric operator and it will be used to show the influence on periodic solutions. The high efficiency of the proposed strategy is presented along with some illustrative examples which demonstrate their periodic interval dealing with the choice of an appropriate continuous linear operator.
Before the Page Time: Maximum Entanglements or the Return of the Monster?
Authors: Bae Jeong-Myeong , Lee Dong Jin , Yeom Dong-han , Zoe Heeseung
Published: August 2022

The conservation of information of evaporating black holes is a very natural consequence of unitarity, which is the fundamental symmetry of quantum mechanics. In order to study the conservation of information, we need to understand the nature of the entanglement entropy. The entropy of Hawking radiation is approximately equal to the maximum of entanglement entropy if a black hole is in a state before the Page time, i.e., when the entropy of Hawking radiation is smaller than the entropy of the black hole. However, if there exists a process generating smaller entanglements rather than maximal entanglements, the entropy of Hawking radiation will become smaller than the maximum of the entanglement entropy before the Page time. If this process accumulates, even though the probability is small, the emitted radiation can eventually be distinguished from the exactly thermal state. In this paper, we provide several interpretations of this phenomenon: (1) information of the collapsed matter emitted before the Page time, (2) there exists a firewall or a non-local effect before the Page time, or (3) the statistical entropy is greater than the areal entropy; a monster is formed. Our conclusion will help resolve the information loss paradox by providing groundwork for further research.
Group Combustion of Dispersed Spherical Core–Shell Nanothermite Particles
Authors: Rahman Mustafa Mutiur , Saieed Ahmed , Khan Muhammad Fasahat , Hickey Jean-Pierre
Published: August 2022

The group combustion characteristics of core–shell nanothermite particles differ from other dispersed solid or liquid fuels. In a core–shell structure, each discrete nanothermite particle can undergo an exothermic reaction as the oxygen atoms in the metal oxide shell undergo a solid state diffusion to oxidize the metal core. This feature allows the spherical core–shell nanothermites to react in the absence of gaseous oxygen, thus modifying their group combustion characteristics compared to char or liquid fuels. Using a number of simplifying assumptions, a theoretical framework was established—based on existing group combustion theory—to examine the characteristics of mass and heat diffusion in nanothermite combustion. First, a model for the quasi-steady state single-particle combustion, in quiescent air, was established. The isolated particle combustion theory serves as the basis for the combustion interaction and mass transfer in a spherical cloud of dispersed nanothermite particles. The type of group combustion is strongly dependent on the diffusion of vapour products, i.e., the interaction is more pronounced when the diffusion of vapour products is higher. The group combustion regimes in dispersed nanothermites were identified and delineated.
Essential and Non-Essential Elements in Razor Clams (Solen marginatus, Pulteney, 1799) from the Domitio Littoral in Campania (Southwestern Tyrrhenian Sea, Italy)
Authors: Esposito Mauro , Canzanella Silvia , Danese Amalia , Pepe Angela , Gallo Pasquale
Published: August 2022

The levels of essential (Cu, Cr, Co, Mn, Se, Zn) and non-essential (As, Be, Bi, Cd, Cs, Ga, Ni, Pb, Sr, Tl, U, V) trace elements were studied in razor clams (Solen marginatus) collected from the Tyrrhenian coast of Southern Italy at five selected sites along the Domitio littoral in the Campania region. The main objectives of this study were to assess the contamination status of these bivalve mollusks and to evaluate the risks to the environment and consumers due to metal contamination. The concentrations of 18 trace elements were determined after microwave-assisted mineralization and by inductively coupled plasma mass spectrometry (ICP-MS). Concentrations of the toxic elements Pb and Cd were below the maximum levels established by Commission Regulation (EC) 1881/2006, while higher average concentrations of arsenic were found at each of the five sites studied. Regarding the other trace elements, contamination levels followed the order: Zn > Sr > Mn > Cu > Se > Cr > V > Ni > Co > Ga > Cs > Be > U > Bi > Tl. No significant differences among the sites were found with regard to any of the trace elements analyzed, and element levels in razor clams did not reflect sediment contamination. The results demonstrated the substantial food safety of the razor clams in this area with respect to heavy metals but revealed a potential health risk due to arsenic contamination in all the areas sampled.
Acute Rubigine® Poisoning in Martinique a French Overseas Department of America: Clinical Characteristics and Prognostic Factors
Authors: Florentin Jonathan , Neviere Remi , Gueye Papa , Mégarbane Bruno , Mehdaoui Hossein , Resiere Dabor
Published: August 2022

Rubigine® is an anti-rust stain remover containing fluorides which is believed to have been the cause of many deaths in Martinique. However, after the modification of its composition in 2006, serious poisoning from old formulas containing fluorides persisted. Our main objective was to determine the clinical characteristics and prognostic factors of these intoxications. Methods: Any patient admitted to the Martinique University Hospital for acute Rubigine® poisoning was included from 1 January 2000 to 31 December 2016. Usual demographic and clinical data were collected and comparisons between surviving and deceased patients made using a univariate analysis and logistic regression. Results: Fifty-five patients were included (mean age: 43 years; sex ratio M/F: 1.1), and the main clinical characteristics were: changes in electrocardiogram (ECG) (80%), digestive system disorders (75%), and neurological disorders (12%). The main features linked to death were the presence of hydrofluoric acid (p < 0.0001), age over 55 years (p = 0.01), hypocalcemia after the initial intravenous calcium supplementation (p = 0.0003), diarrhea (p < 0.0001), hypersialorrhea (p < 0.0001), myocardial excitability (p < 0.0001), and state of shock (p < 0.0001). Three patients required circulatory support by venous-arterial ECMO. Mortality was 10.9%. Conclusions: Rubigine® poisoning is responsible for significant morbidity and mortality. Fortunately, its incidence as well as mortality has sharply decreased in Martinique thanks to the measures taken by the French state. This retrospective work nevertheless shows that acute intoxication by the old formula of Rubigine® remains the main factor of poor prognosis.
The Binding Ability of Mercury (Hg) to Photosystem I and II Explained the Difference in Its Toxicity on the Two Photosystems of Chlorella pyrenoidosa
Authors: Wang Shuzhi , Duo Jia , Wufuer Rehemanjiang , Li Wenfeng , Pan Xiangliang
Published: August 2022

Mercury (Hg) poses high toxicity to organisms including algae. Studies showed that the growth and photosynthesis of green algae such as Chlorella are vulnerable to Hg stress. However, the differences between the activities and tolerance of photosystem I and II (PSI and PSII) of green microalgae under Hg exposure are still little known. Responses of quantum yields and electron transport rates (ETRs) of PSI and PSII of Chlorella pyrenoidosa to 0.05–1 mg/L Hg2+ were simultaneously measured for the first time by using the Dual-PAM-100 system. The photosystems were isolated to analyze the characteristics of toxicity of Hg during the binding process. The inhibition of Hg2+ on growth and photosystems was found. PSII was more seriously affected by Hg2+ than PSI. After Hg2+ exposure, the photochemical quantum yield of PSII [Y(II)] decreased with the increase in non-photochemical fluorescence quenching [Y(NO) and Y(NPQ)]. The toxic effects of Hg on the photochemical quantum yield and ETR in PSI were lower than those of PSII. The stimulation of cyclic electron yield (CEF) was essential for the stability and protection of PSI under Hg stress and played an important role in the induction of non-photochemical quenching (NPQ). The results showed a strong combination ability of Hg ions and photosystem particles. The number of the binding sites (n) of Hg on PSII was more than that of PSI, which may explain the different toxicity of Hg on PSII and PSI.
Antibiotics in Raw Meat Samples: Estimation of Dietary Exposure and Risk Assessment
Authors: Stavroulaki Athina , Tzatzarakis Manolis N. , Karzi Vasiliki , Katsikantami Ioanna , Renieri Elisavet , Vakonaki Elena , Avgenaki Maria , Alegakis Athanasios , Stan Miriana , Kavvalakis Matthaios , Rizos Apostolos K. , Tsatsakis Aristidis
Published: August 2022

The extensive use of antibiotics in livestock farming poses increased concerns for human health as residues of these substances are present in edible tissues. The aim of this study was the determination of the levels of four groups of antibiotics (sulfonamides—SAs, tetracyclines—TCs, streptomycines—STr and quinolones—QNLs) in meat samples (muscles, livers and kidneys from beef, chicken and pork) and the estimation of the dietary exposure to antibiotics from meat consumption and the potential hazard for human health. Fifty-four samples of raw meat were randomly collected in 2018 from the Cretan market, Greece and analyzed both with an enzyme-linked immunosorbent assay (ELISA) and liquid chromatography–mass spectrometry (LC–MS). According to the results derived from the ELISA method, only 2% of the meat samples were free from antibiotics, 2% were detected with 4 antibiotics and the great majority of the samples (87%) were detected with 2 to 3 antibiotics. SAs presented the highest detection frequencies for all samples whereas TCs were not detected in any bovine sample. The highest median concentration was detected for STr in bovine muscles (182.10 μg/kg) followed by QNLs (93.36 μg/kg) in pork kidneys whereas the chicken samples had higher burdens of QNLs compared to the other meat samples. LC–MS analysis showed that oxytetracycline (OTC) was the most common antibiotic in all samples. The highest median concentration of all antibiotics was detected for doxycycline (DOX) (181.73 μg/kg in pork kidney) followed by OTC in bovine liver (74.46 μg/kg). Risk characterization was applied for each of the two methods; The hazard quotients (HQ) did not exceed 0.059 for the ELISA method and 0.113 for the LC–MS method for any group of antibiotics, whereas the total hazard indexes (HI) were 0.078 and 0.021, respectively. The results showed the presence of different groups of antibiotics in meat from the Cretan market and that the health risk to antibiotics is low. A risk assessment analysis conducted for meat consumption and corrected for the aggregated exposure revealed no risk for the consumers.
Health Outcomes in Children Associated with Prenatal and Early-Life Exposures to Air Pollution: A Narrative Review
Authors: Gheissari Roya , Liao Jiawen , Garcia Erika , Pavlovic Nathan , Gilliland Frank D. , Xiang Anny H. , Chen Zhanghua
Published: August 2022

(1) Background: The developmental origins of health and disease (DOHaD) hypothesis links adverse fetal exposures with developmental mal-adaptations and morbidity later in life. Short- and long-term exposures to air pollutants are known contributors to health outcomes; however, the potential for developmental health effects of air pollution exposures during gestation or early-childhood have yet to be reviewed and synthesized from a DOHaD lens. The objective of this study is to summarize the literature on cardiovascular and metabolic, respiratory, allergic, and neuropsychological health outcomes, from prenatal development through early childhood, associated with early-life exposures to outdoor air pollutants, including traffic-related and wildfire-generated air pollutants. (2) Methods: We conducted a search using PubMed and the references of articles previously known to the authors. We selected papers that investigated health outcomes during fetal or childhood development in association with early-life ambient or source-specific air pollution exposure. (3) Results: The current literature reports that prenatal and early-childhood exposures to ambient and traffic-related air pollutants are associated with a range of adverse outcomes in early life, including cardiovascular and metabolic, respiratory and allergic, and neurodevelopmental outcomes. Very few studies have investigated associations between wildfire-related air pollution exposure and health outcomes during prenatal, postnatal, or childhood development. (4) Conclusion: Evidence from January 2000 to January 2022 supports a role for prenatal and early-childhood air pollution exposures adversely affecting health outcomes during development. Future studies are needed to identify both detrimental air pollutants from the exposure mixture and critical exposure time periods, investigate emerging exposure sources such as wildfire, and develop feasible interventional tools.
Effects of Selected Metal Nanoparticles (Ag, ZnO, TiO2) on the Structure and Function of Reproductive Organs
Authors: Dianová Lucia , Tirpák Filip , Halo Marko , Slanina Tomáš , Massányi Martin , Stawarz Robert , Formicki Grzegorz , Madeddu Roberto , Massányi Peter
Published: August 2022

Various studies have shown that the reproductive organs are highly sensitive to toxic elements found in the environment. Due to technological progress, the use of nanoparticles has become more common nowadays. Nanoparticles are used for drug delivery because their dimensions allow them to circulate throughout the body and enter directly into the cell. Antimicrobial properties are increasingly used in the manufacture of medical devices, textiles, food packaging, cosmetics, and other consumer products. Nanoparticles provide several benefits, but aspects related to their effects on living organisms and the environment are not well known. This review summarizes current in vivo, and in vitro animal studies focused on the evaluation of toxicity of selected metal nanoparticles (Ag, ZnO, TiO2) on male and female reproductive health. It can be concluded that higher concentrations of metal nanoparticles in the male reproductive system can cause a decrease in spermatozoa motility, viability and disruption of membrane integrity. Histopathological changes of the testicular epithelium, infiltration of inflammatory cells in the epididymis, and prostatic hyperplasia have been observed. Nanoparticles in the female reproductive system caused their accumulation in the ovaries and uterus. Metal nanoparticles most likely induce polycystic ovary syndrome and follicular atresia, inflammation, apoptosis, and necrosis also occurred.
Toxicity of Orthodontic Brackets Examined by Single Cell Tracking
Authors: Wishney Morgan , Mahadevan Swarna , Cornwell James Anthony , Savage Tom , Proschogo Nick , Darendeliler M. Ali , Zoellner Hans
Published: August 2022

Subtle toxic effects may be masked in traditional assays that average or summate the response of thousands of cells. We overcome this by using the recent method of single cell tracking in time-lapse recordings. This follows the fate and behavior of individual cells and their progeny and provides unambiguous results for multiple simultaneous biological responses. Further, single cell tracking permits correlation between progeny relationships and cell behavior that is not otherwise possible, including disruption by toxins and toxicants of similarity between paired sister cells. Notably, single cell tracking seems not to have been previously used to study biomaterials toxicity. The culture medium was pre-conditioned by 79 days incubation with orthodontic brackets from seven separate commercial sources. Metal levels were determined by Inductively Coupled Plasma Mass Spectrometry. Metal levels varied amongst conditioned media, with elevated Cr, Mn, Ni, and Cu and often Mo, Pb, Zn, Pd, and Ag were occasionally found. The effect on human dermal fibroblasts was determined by single cell tracking. All bracket-conditioned media reduced cell division (p < 0.05), while some reduced cell migration (p < 0.05). Most bracket-conditioned media increased the rate of asynchronous sister cell division (p < 0.05), a seemingly novel measure for toxicity. No clear effect on cell morphology was seen. We conclude that orthodontic brackets have cytotoxic effects, and that single cell tracking is effective for the study of subtle biomaterials cytotoxicity.
Biochar Is Not Durable for Remediation of Heavy Metal-Contaminated Soils Affected by Acid-Mine Drainage
Authors: Qin Junhao , Wang Xi , Ying Jidong , Lin Chuxia
Published: August 2022

Biochar is a soil conditioner for enhancing plant growth and reducing plants’ uptake of heavy metals. However, the protonation of biochar surfaces in acid soils can weaken the capacity of biochar to reduce the phytoavailability of soil-borne heavy metals over time. The aim of this study was to test this hypothesis by performing a plant-growth experiment with five harvest cycles to examine the durability of rice-straw biochar for the remediation of an acidic-mine-water-contaminated soil. The application of the biochar significantly reduced the phytoavailability of the heavy metals and inhibited the plant uptake of cationic heavy metals but not anionic Cr. The beneficial effects of the biochar were weakened with the increasing number of harvest cycles caused by the gradual protonation of the biochar surfaces, which resulted in the desorption of the adsorbed heavy metals. The weakening capacity of the biochar to reduce the heavy-metal uptake by the vegetable plants was more evident for Cu, Zn, and Pb compared to Ni and Cd. The experimental results generally confirmed the hypothesis. It was also observed that the bioaccessible amount of various metals in the edible portion of the vegetable was also reduced as a result of the biochar application.
Ce3+/Ce4+-Doped ZrO2/CuO Nanocomposite for Enhanced Photocatalytic Degradation of Methylene Blue under Visible Light
Authors: Chu Manh Nhuong , Nguyen Lan T. H. , Truong Mai Xuan , Do Tra Huong , Duong Thi Tu Anh , Nguyen Loan T. T. , Pham Mai An , Tran Thi Kim Ngan , Ngo Thi Cam Quyen , Pham Van Huan
Published: August 2022

In recent years, photocatalysis has been used as an environmentally friendly method for the degradation of organic pigments in water. In this study, Ce3+/Ce4+-doped ZrO2/CuO as a mixed semiconductor oxide was successfully prepared by a one-step hydrothermal method. The Ce3+/Ce4+-doped ZrO2/CuO has shown high degradation efficiency of methylene blue (MB), and the maximum degradation percentage was observed to be 94.5% at 180 min under irradiation visible light. The photocatalytic activity increases significantly by doping Ce3+/Ce4+ in ZrO2/CuO for MB degradation. Ce3+/Ce4+ doping is shown to reduce the (e-/h+) recombination rate and improve the charge transfer, leading to enhanced photocatalytic activity of materials. The materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), FTIR, EDS, BET and diffuse reflectance spectroscopy (DRS).
Epidemiological Profile of a Human Hepatitis E Virus Outbreak in 2018, Chattogram, Bangladesh
Authors: Owada Kei , Sarkar Joyantee , Rahman Md. Kaisar , Khan Shahneaz Ali , Islam Ariful , Hassan Mohammad Mahmudul , Soares Magalhães Ricardo J.
Published: August 2022

Hepatitis E virus (HEV) is a waterborne zoonotic disease that can result in a high fatality rate in pregnant women and infants. In 2018, a large HEV outbreak emerged in Chattogram, Bangladesh, resulting in 2800 cases and a significant public health response to mitigate the transmission. While the source of the outbreak remained poorly understood, authorities suggested that possible risk factors for HEV infection included contamination of water supply, exacerbated by concurrent severe flooding events in the community. A cross-sectional study was conducted to investigate the distribution and risk factors for HEV seroprevalence between January and December 2018 in the Chattogram city area. A total of 505 blood samples were collected from symptomatic patients of 10 hospitals who met the case definition for an HEV infection. Standard ELISA tests were performed in all patients to identify anti-HEV antibodies. The size and location of HEV seroprevalence clusters within Chattogram were investigated using SaTScan. We investigated the association between risk of HEV infection and individual and environmentally lagged risk factors using Bernoulli generalised linear regression models. Our results indicate an overall HEV seroprevalence of 35% with significant variation according to sex, source of drinking water, and boiling of drinking water. A positive cross-correlation was found between HEV exposure and precipitation, modified normalised difference water index (MNDWI), and normalised difference vegetation index (NDVI). Our model indicated that risk of infection was associated with sex, age, source of drinking water, boiling of water, increased precipitation, and increased MNDWI. The results from this study indicate that source and boiling of drinking water and increased precipitation were critical drivers of the 2018 HEV outbreak. The communities at highest risk identified in our analyses should be targeted for investments in safe water infrastructure to reduce the likelihood of future HEV outbreaks in Chattogram.
Advances in Mass Spectrometers for Flyby Space Missions for the Analysis of Biosignatures and Other Complex Molecules
Authors: Fausch Rico G. , Schertenleib Janis A. , Wurz Peter
Published: August 2022

Spacecraft flybys provide access to the chemical composition of the gaseous envelope of the planetary object. Typical relative encounter velocities range from km/s to tens of km/s in flybys. For speeds exceeding about 5 km/s, modern mass spectrometers analyzing the rapidly encountering gas suffer from intrinsic hypervelocity impact-induced fragmentation processes causing ambiguous results when analyzing complex molecules. In this case, instruments use an antechamber, inside which the incoming species collide many times with the chamber wall. These collisions cause the desired deceleration and thermalization of the gas molecules. However, these collisions also dissociate molecular bonds, thus fragmenting the molecules, and possibly forming new ones precluding scientists from inferring the actual chemical composition of the sampled gas. We developed a novel time-of-flight mass spectrometer that handles relative encounter velocities of up to 20 km/s omitting an antechamber and its related fragmentation. It analyzes the complete mass range of m/z 1 to 1000 at an instance. This innovation leads to unambiguous analysis of complex (organic) molecules. Applied to Enceladus, Europa or Io, it will provide reliable chemical composition datasets for exploration of the Solar System to determine its status, origin and evolution.
Time-of-Day Variation in SARS-CoV-2 RNA Levels during the Second Wave of COVID-19
Authors: Zhuang Xiaodong , Wang Wei , Borrmann Helene , Balfe Peter , Matthews Philippa C. , Eyre David W. , Klerman Elizabeth B. , McKeating Jane A.
Published: August 2022

Circadian rhythms influence and coordinate an organism’s response to its environment and to invading pathogens. We studied the diurnal variation in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA in nasal/throat swabs collected in late 2020 to spring 2021 in a population immunologically naïve to SARS-CoV-2 and prior to widespread vaccination. SARS-CoV-2 diagnostic PCR data from 1698 participants showed a significantly higher viral load in samples obtained in the afternoon, in males, and in hospitalised patients when linear mixed modelling was applied. This study illustrates the importance of recording sample collection times when measuring viral replication parameters in clinical and research studies.
Viral and Host Factors Regulating HIV-1 Envelope Protein Trafficking and Particle Incorporation
Authors: Anokhin Boris , Spearman Paul
Published: August 2022

The HIV-1 envelope glycoprotein (Env) is an essential structural component of the virus, serving as the receptor-binding protein and principal neutralizing determinant. Env trimers are incorporated into developing particles at the plasma membrane of infected cells. Incorporation of HIV-1 Env into particles in T cells and macrophages is regulated by the long Env cytoplasmic tail (CT) and the matrix region of Gag. The CT incorporates motifs that interact with cellular factors involved in endosomal trafficking. Env follows an unusual pathway to arrive at the site of particle assembly, first traversing the secretory pathway to the plasma membrane (PM), then undergoing endocytosis, followed by directed sorting to the site of particle assembly on the PM. Many aspects of Env trafficking remain to be defined, including the sequential events that occur following endocytosis, leading to productive recycling and particle incorporation. This review focuses on the host factors and pathways involved in Env trafficking, and discusses leading models of Env incorporation into particles.
Early or Simultaneous Infection with Infectious Pancreatic Necrosis Virus Inhibits Infectious Hematopoietic Necrosis Virus Replication and Induces a Stronger Antiviral Response during Co-infection in Rainbow Trout (Oncorhynchus mykiss)
Authors: Shao Yizhi , Zhao Jingzhuang , Ren Guangming , Lu Tongyan , Chen Xiaoyu , Xu Liming
Published: August 2022

Infectious hematopoietic necrosis (IHN) and infectious pancreatic necrosis (IPN) are the most common viral diseases of salmon in aquaculture worldwide. The co-infection of rainbow trout (Oncorhynchus mykiss) with IHN virus (IHNV) and IPN virus (IPNV) is known to occur. To determine the influence of IPNV on IHNV in co-infection, rainbow trout were intraperitoneally (i.p.) injected with IPNV at different time intervals prior to, simultaneously to, or after IHNV infection. The replication of IHNV in the brain, gill, heart, liver, spleen, and head kidney was detected by real-time quantitative polymerase chain reaction (qRT-PCR). The results showed that when rainbow trout were i.p. injected with IPNV prior to, simultaneously to, or after IHNV on 2 day (d), IHNV replication was inhibited (p < 0.05) in all collected tissues. Nevertheless, when rainbow trout were i.p. injected with IPNV after IHNV on 7 d (H7P), IHNV replication was only inhibited (p < 0.05) in the liver 14 d post-IHNV infection. Moreover, stronger antiviral responses occurred in all challenge groups. Our results suggest that IPNV can inhibit IHNV replication before or simultaneously with IHNV infection, and induce a stronger antiviral response, and that this inhibition is most sensitive in the liver. Early i.p. injection of IPNV can significantly reduce the mortality of rainbow trout, compared with the group only injected with IHNV.
CD24 Expression Dampens the Basal Antiviral State in Human Neuroblastoma Cells and Enhances Permissivity to Zika Virus Infection
Authors: Kedarinath Kritika , Fox Candace R. , Crowgey Erin , Mazar Joseph , Phelan Peter , Westmoreland Tamarah J. , Alexander Kenneth A. , Parks Griffith D.
Published: August 2022

Zika virus (ZIKV) exhibits distinct selectivity for infection of various cells and tissues, but how host cellular factors modulate varying permissivity remains largely unknown. Previous studies showed that the neuroblastoma cell line SK-N-AS (expressing low levels of cellular protein CD24) was highly restricted for ZIKV infection, and that this restriction was relieved by ectopic expression of CD24. We tested the hypothesis that CD24 expression allowed ZIKV replication by suppression of the antiviral response. SK-N-AS cells expressing an empty vector (termed CD24-low cells) showed elevated basal levels of phosphorylated STAT1, IRF-1, IKKE, and NFκB. In response to exogenously added type I interferon (IFN-I), CD24-low cells had higher-level induction of antiviral genes and activity against two IFN-I-sensitive viruses (VSV and PIV5-P/V) compared to SK-N-AS cells with ectopic CD24 expression (termed CD24-high cells). Media-transfer experiments showed that the inherent antiviral state of CD24-low cells was not dependent on a secreted factor such as IFN-I. Transcriptomics analysis revealed that CD24 expression decreased expression of genes involved in intracellular antiviral pathways, including IFN-I, NFκB, and Ras. Our findings that CD24 expression in neuroblastoma cells represses intracellular antiviral pathways support the proposal that CD24 may represent a novel biomarker in cancer cells for susceptibility to oncolytic viruses.
Protection against Marburg Virus and Sudan Virus in NHP by an Adenovector-Based Trivalent Vaccine Regimen Is Correlated to Humoral Immune Response Levels
Authors: Tiemessen Machteld M. , Solforosi Laura , Dekking Liesbeth , Czapska-Casey Dominika , Serroyen Jan , Sullivan Nancy J. , Volkmann Ariane , Pau Maria Grazia , Callendret Benoit , Schuitemaker Hanneke , Luhn Kerstin , Zahn Roland , Roozendaal Ramon
Published: August 2022

The Marburg virus (MARV) and Sudan virus (SUDV) belong to the filovirus family. The sporadic human outbreaks occur mostly in Africa and are characterized by an aggressive disease course with high mortality. The first case of Marburg virus disease in Guinea in 2021, together with the increased frequency of outbreaks of Ebola virus (EBOV), which is also a filovirus, accelerated the interest in potential prophylactic vaccine solutions against multiple filoviruses. We previously tested a two-dose heterologous vaccine regimen (Ad26.Filo, MVA-BN-Filo) in non-human primates (NHP) and showed a fully protective immune response against both SUDV and MARV in addition to the already-reported protective effect against EBOV. The vaccine-induced glycoprotein (GP)-binding antibody levels appear to be good predictors of the NHP challenge outcome as indicated by the correlation between antibody levels and survival outcome as well as the high discriminatory capacity of the logistic model. Moreover, the elicited GP-specific binding antibody response against EBOV, SUDV, and MARV remains stable for more than 1 year. Overall, the NHP data indicate that the Ad26.Filo, MVA-BN-Filo regimen may be a good candidate for a prophylactic vaccination strategy in regions at high risk of filovirus outbreaks.
COVID-19-Associated Mucormycosis: A Matter of Concern Amid the SARS-CoV-2 Pandemic
Authors: Chandley Pankaj , Subba Priyanka , Rohatgi Soma
Published: August 2022

Mucormycosis is an invasive fungal infection caused by fungi belonging to order Mucorales. Recently, with the increase in COVID-19 infections, mucormycosis infections have become a matter of concern globally, because of the high morbidity and mortality rates associated with them. Due to the association of mucormycosis with COVID-19 disease, it has been termed COVID-19-associated mucormycosis (CAM). In the present review, we focus on mucormycosis incidence, pathophysiology, risk factors, immune dysfunction, interactions of Mucorales with endothelial cells, and the possible role of iron in Mucorales growth. We review the limitations associated with current diagnostic procedures and the requirement for more specific, cost-effective, convenient, and sensitive assays, such as PCR-based assays and monoclonal antibody-based assays for the effective diagnosis of mucormycosis. We discuss the current treatment options involving antifungal drug therapies, adjunctive therapy, surgical treatment, and their limitations. We also review the importance of nutraceuticals-based therapy for the prevention as well as treatment of mucormycosis. Our review also highlights the need to explore the potential of novel immunotherapeutics, which include antibody-based therapy, cytokine-based therapy, and combination/synergistic antifungal therapy, as treatment options for mucormycosis. In summary, this review provides a complete overview of COVID-19-associated mucormycosis, addressing the current research gaps and future developments required in the field.
Low Measles Seropositivity Rate among Thai Adolescents in the Thai National Immunization Program
Authors: Puthanakit Thanyawee , Anugulruengkitt Suvaporn , Angsuwatcharakon Piyada , Bunjoungmanee Pornumpa , Kowitdamrong Ekasit , Primsirikunawut Athiwat , Intarakhao Sukkrawan , Chetsonwisorn Panadda , Sophonphan Jiratchaya , Tangsathapornpong Auchara
Published: August 2022

To achieve the goal of measles elimination, herd immunity with 95% seroprotection in the community is required. This study aimed to describe the measles seropositivity rate among Thai children and adolescents. A cross-sectional study was conducted among children aged 3–18 years in Bangkok and its suburbs. Measles IgG antibodies were measured using a EUROIMMUN enzyme-linked immunosorbent assay kit. Seropositivity is defined as a measles IgG titer of ≥200 IU/L, due to a correlation with a >85% positive rate with a plaque reduction neutralizing titer of >120. Factors associated with seropositivity were analyzed using logistic regression analysis. From May to July 2020, 570 children with a median (IQR) age of 11.7 (9.4–14.8) years were enrolled. The geometric mean titer (GMT) of anti-measles IgG was 281 IU/L (95% CI; 257–306). The proportion of children with seropositivity was inversely correlated with age; 3–5 years 85.3%, 6–9 years 72.5%, 10–14 years 50.7%, and 15–18 years 56.3%. Adolescents aged 10–18 years had a lower measles seropositivity rate compared with young children; aOR 0.29 (95% CI 0.17–0.48). Only half of the adolescents who received two doses of measles-containing vaccine maintained measles IgG above the seropositive level. A measles booster dose for young adults may be needed to achieve the measles elimination goal.
Immunotherapeutic Strategies for Head and Neck Squamous Cell Carcinoma (HNSCC): Current Perspectives and Future Prospects
Authors: Gao Lei , Zhang Anqi , Yang Fuyuan , Du Wei
Published: August 2022

Neoantigens are abnormal proteins produced by genetic mutations in somatic cells. Because tumour neoantigens are expressed only in tumour cells and have immunogenicity, they may represent specific targets for precision immunotherapy. With the reduction in sequencing cost, continuous advances in artificial intelligence technology and an increased understanding of tumour immunity, neoantigen vaccines and adoptive cell therapy (ACT) targeting neoantigens have become research hotspots. Approximately 900,000 patients worldwide are diagnosed with head and neck squamous cell carcinoma (HNSCC) each year. Due to its high mutagenicity and abundant lymphocyte infiltration, HNSCC naturally generates a variety of potential new antigen targets that may be used for HNSCC immunotherapies. Currently, the main immunotherapy for HNSCC is use of immune checkpoint inhibitors(ICIs). Neoantigen vaccines and adoptive cell therapy targeting neoantigens are extensions of immunotherapy for HNSCC, and a large number of early clinical trials are underway in combination with immune checkpoint inhibitors for the treatment of recurrent or metastatic head and neck squamous cell carcinoma (R/M HNSCC). In this paper, we review recent neoantigen vaccine trials related to the treatment of HNSCC, introduce adoptive cell therapy targeting neoantigens, and propose a potential treatment for HNSCC. The clinical application of immune checkpoint inhibitor therapy and its combination with neoantigen vaccines in the treatment of HNSCC are summarized, and the prospect of using neoantigen to treat HNSCC is discussed and proposed.
HPV Vaccination Coverage Rate in a Rural Area: An Observational, Retrospective, and Cohort Study
Authors: Colomé-Ceballos Lara , Clua-Espuny Josep Lluís , Fernández-Sáez José , Ceballos-García Concepción , Andrés-Cubells Natàlia , Pla-Farnós Maria Jesús
Published: August 2022

In order to reduce the incidence and mortality rate of cervical cancer, the World Health Organization (WHO) declared the Global Strategy Goal for 2030, advocating for reaching a vaccination coverage rate of >90% against human papillomavirus for girls by the age of 15 years. The main objectives of this study were (1) to determine the papillomavirus vaccination coverage among women 15–40 years old and (2) to identify the at-risk subgroups and possible barriers to achieving WHO’s 2030 goal. Multicentre, observational, retrospective, and community-based cohort studies were conducted on women from a rural area in southern Catalonia until 31 December 2021. A total of 23,136 women were included, with a mean age of 26.6 (SD = 5.6) years. The average dose number was 1.7 (SD = 0.7). The results showed overall vaccination coverage of 17.4% among the target women. This coverage was unequal across regions (16.6–24.5%, p < 0.001), primary healthcare teams (15.5–24.3%, p < 0.001), and age groups (56.7% (15–19-year-olds) vs. 3.8% (35–40-year-olds), p < 0.001), related to accessibility to vaccination and economic–geographical indicators. Clinical practice guidelines on screening individuals at risk in terms of vaccination access and public vaccination protocols should be implemented in order to improve the vaccination coverage rate.
COVID-19 Vaccination and Medical Liability: An International Perspective in 18 Countries
Authors: Beccia Flavia , Rossi Maria Francesca , Amantea Carlotta , Villani Leonardo , Daniele Alessandra , Tumminello Antonio , Aristei Luna , Santoro Paolo Emilio , Borrelli Ivan , Ricciardi Walter , Gualano Maria Rosaria , Moscato Umberto
Published: August 2022

The COVID-19 vaccination has proven to be the most effective prevention measure, reducing deaths and hospitalizations and allowing, in combination with non-pharmacological interventions, the pandemic to be tackled. Although most of the adverse reactions to vaccination present mild symptoms and serious effects are very rare, they can be the cause of legal action against the healthcare workers (HCWs) who administered it. To highlight differences in the medical liability systems, we performed a search for the three most populous countries in each continent on vaccine injury compensation programs, new laws or policies to protect HCWs administering vaccinations introduced during the COVID-19 pandemic, and policies on mandatory vaccinations, on literature databases and institutional sites. We found that in seven countries the medical liability system is based on Common Law, while in eleven it is mainly based on Civil Law. Considering the application of specific laws to protect HCWs who vaccinate during the pandemic, only the USA and Canada provided immunity from liability. Among the countries we analyzed, fourteen have adopted compensation funds. From an international perspective, our results highlight that in eleven (61.1%) countries medical liability is mainly based on Civil Law, whilst in seven (38.9%) it is based on Common Law.
HPV Vaccination and Cervical Cancer Screening: Assessing Awareness, Attitudes, and Adherence in Detained Women
Authors: Di Giuseppe Gabriella , Folcarelli Lucio , Lanzano Raffaele , Napolitano Francesco , Pavia Maria
Published: August 2022

Background: This study assessed awareness, attitudes, and uptake of human papillomavirus (HPV) vaccination and cervical cancer screening in detained women. Methods: The cross-sectional study was conducted from April to June 2022 in four women prisons in Italy. Results: 41.1% of participants recognized HPV infection as an sexually transmitted diseases (STD), 36.4% identified cervical, and 16.8% oral cancer as an HPV-associated disease. Overall, 70% had never heard of HPV vaccination, and 45.8% believed it is effective to prevent cervical cancer. Among the age-eligible women for HPV vaccination, none reported to have undergone it, nor had talked about it with a physician in the previous year. Only 13.5% declared to have ever undergone cervical cancer screening, and adherence was significantly higher in those who were involved in a working activity in prison, who were aware that HPV infection is an STD and that can cause cervical and oral cancer, and who were older at their first sexual intercourse. Conclusion: These findings documented an extremely low awareness of HPV infection and an unsatisfactory adherence to prevention through HPV vaccination and cervical cancer screening. There is a need for evidence-based interventions for incarcerated women to promote participation in HPV vaccination and cervical cancer screening programs as routine activities.