bluuebunny/crossref_metadata_2025 huggingface dataset:
Pax2a, but not pax2b, influences cell survival and periocular mesenchyme localization to facilitate zebrafish optic fissure closure
Authors: Lusk Sarah , Kwan Kristen M.
Published: September 2021

Background

Pax2 is required for optic fissure development in many organisms, including humans and zebrafish. Zebrafish loss‐of‐function mutations in pax2a display coloboma, yet the etiology of the morphogenetic defects is unclear. Further, pax2 is duplicated in zebrafish, and a role for pax2b in optic fissure development has not been examined.

Results

Using a combination of imaging and molecular genetics, we interrogated a potential role for pax2b and examined how loss of pax2 affects optic fissure development. Although optic fissure formation appears normal in pax2 mutants, an endothelial‐specific subset of periocular mesenchyme (POM) fails to initially localize within the optic fissure, yet both neural crest and endothelial‐derived POM ectopically accumulate at later stages in pax2a and pax2a; pax2b mutants. Apoptosis is not up‐regulated within the optic fissure in pax2 mutants, yet cell death is increased in tissues outside of the optic fissure, and when apoptosis is inhibited, coloboma is partially rescued. In contrast to pax2a, loss of pax2b does not appear to affect optic fissure morphogenesis.

Conclusions

Our results suggest that pax2a, but not pax2b, supports cell survival outside of the optic fissure and POM abundance within it to facilitate optic fissure closure.
The peril and promise of sensitivity in eating disorders
Authors: Sim Leslie , Peterson Carol B.
Published: September 2021

Differential susceptibility, a reconceptualization of the diathesis‐stress model of psychopathology, describes gene–environment interactions that reflect individual differences in responsiveness to environmental influences, both detrimental and beneficial. This model has been described metaphorically by the classification of orchids, which thrive under optimal care but wither under adverse conditions, and dandelions, which weather broad environmental circumstances but are less responsive to careful cultivation. Etiological research in the field of eating disorders has largely focused on the identification of specific behavioral phenotypes, temperamental traits, genotypes and neurobiological processes that confer risk. In this article, we propose that these putative vulnerability factors represent phenotypes and endophenotypes of a genetic predisposition towards environmental sensitivity. We assert that this sensitivity not only transmits eating disorder risk but also confers resilience, depending on the circumstances. In particular, we propose that differential susceptibility can be used as a framework to organize disparate temperamental and neurobiological findings and their complex interplay with various developmental, environmental and sociocultural influences to increase eating disorder risk and treatment responsiveness. Finally, we assert that viewed through the lens of differential susceptibility, sensitivity can be leveraged to refine our interventions and develop novel treatment and prevention strategies to support favorable outcomes for individuals with eating disorders.
A molecular and ecological study of Grillotia (Cestoda: Trypanorhyncha) larval infection in small to mid‐sized benthonic sharks in the Gulf of Naples, Mediterranean Sea
Authors: Santoro Mario , Bellisario Bruno , Crocetta Fabio , Degli Uberti Barbara , Palomba Marialetizia
Published: September 2021

Aim

Trypanorhyncha cestodes comprise a wide range of heteroxenous parasites infecting elasmobranchs as definitive hosts. Limited data exist on the larval infection of these cestodes and the role of intermediate and paratenic hosts in the life cycle of these parasites. We investigated the factors that determine the occurrence and the level of infection of Grillotia plerocerci in the skeletal muscles of various benthonic sharks and analyzed the parasites through an integrative taxonomic approach.

Location

Mediterranean Sea.

Methods

Sharks obtained as bycatch of commercial trawling activities (i.e., Etmopterus spinax, Galeus melastomus, and Scyliorhinus canicula) were used in this study. Data from a limited number of Dalatias licha and Scyliorhinus stellaris were also included. Grillotia plerocerci were molecularly characterized using the partial 28S large subunit rDNA. Boosted regression trees were used to model the relationship between the abundance of infection with both morphological and physiological predictors in each host.

Results

Plerocerci of Grillotia were detected in all shark species except S. stellaris. Host species significantly differed in terms of parasite abundance, with the highest and lowest prevalence and abundance of infection detected in G. melastomus and E. spinax, respectively. The relative influence of the traits involved in explaining the parasite abundance was related to the host size in G. melastomus, while both morphology‐ and physiology‐related traits explained the patterns observed in E. spinax and S. canicula. The 28S rDNA sequences shared an identity of ∼99.40% with a Grillotia species previously found in the Mediterranean Sea. At intraspecific level, two different genotypes were found. A first type was retrieved only from D. licha, whereas a second type was found in G. melastomus, E. spinax, and S. canicula.

Main conclusions

Present results suggest that the two genotypes could be involved in different consumer‐resource systems and confirm most of the examined shark species as transport hosts of Grillotia species for unknown larger top predators.
The influence of ultraviolet reflectance differs between conspicuous aposematic signals in neotropical butterflies and poison frogs
Authors: Yeager Justin , Barnett James B.
Published: September 2021

Warning signals are often characterized by highly contrasting, distinctive, and memorable colors. Greater chromatic (hue) and achromatic (brightness) contrast have both been found to contribute to greater signal efficacy, making longwave colored signals (e.g., red and yellow), that are perceived by both chromatic and achromatic visual pathways, particularly common. Conversely, shortwave colors (e.g., blue and ultraviolet) do not contribute to luminance perception yet are also commonly found in warning signals. Our understanding of the role of UV in aposematic signals is currently incomplete as UV perception is not universal, and evidence for its utility is at best mixed. We used visual modeling to quantify how UV affects signal contrast in aposematic heliconiian butterflies and poison frogs both of which reflect UV wavelengths, occupy similar habitats, and share similar classes of predators. Previous work on butterflies has found that UV reflectance does not affect predation risk but is involved in mate choice. As the butterflies, but not the frogs, have UV‐sensitive vision, the function of UV reflectance in poison frogs is currently unknown. We found that despite showing up strongly in UV photographs, UV reflectance only appreciably affected visual contrast in the butterflies. As such, these results support the notion that although UV reflectance is associated with intraspecific communication in butterflies, it appears to be nonfunctional in frogs. Consequently, our data highlight that we should be careful when assigning a selection‐based benefit to the presence of UV reflectance.
Activation of Transition Metal (Fe, Co and Ni)‐Oxide Nanoclusters by Nitrogen Defects in Carbon Nanotube for Selective CO2 Reduction Reaction
Authors: Cheng Yi , Chen Jinfan , Yang Chujie , Wang Huiping , Johannessen Bernt , Thomsen Lars , Saunders Martin , Xiao Jianping , Yang Shize , Jiang San Ping
Published: September 2021

The electrochemical carbon dioxide reduction reaction (CO2RR), which can produce value‐added chemical feedstocks, is a proton‐coupled‐electron process with sluggish kinetics. Thus, highly efficient, cheap catalysts are urgently required. Transition metal oxides such as CoOx, FeOx, and NiOx are low‐cost, low toxicity, and abundant materials for a wide range of electrochemical reactions, but are almost inert for CO2RR. Here, we report for the first time that nitrogen doped carbon nanotubes (N‐CNT) have a surprising activation effect on the activity and selectivity of transition metal‐oxide (MOx where M = Fe, Ni, and Co) nanoclusters for CO2RR. MOx supported on N‐CNT, MOx/N‐CNT, achieves a CO yield of 2.6–2.8 mmol cm−2 min−1 at an overpotential of −0.55 V, which is two orders of magnitude higher than MOx supported on acid treated CNTs (MOx/O‐CNT) and four times higher than pristine N‐CNT. The faraday efficiency for electrochemical CO2‐to‐CO conversion is as high as 90.3% at overpotential of 0.44 V. Both in‐situ XAS measurements and DFT calculations disclose that MOx nanoclusters can be hydrated in CO2 saturated KHCO3, and the N defects of N‐CNT effectively stabilize these metal hydroxyl species under carbon dioxide reduction reaction conditions, which can split the water molecules and provide local protons to inhibit the poisoning of active sites under carbon dioxide reduction reaction conditions.
Acute myocarditis after COVID‐19 vaccination with mRNA‐1273 in a patient with former SARS‐CoV‐2 infection
Authors: Nguyen Tien Dung , Mall Gerhard , Westphal Julian Georg , Weingärtner Oliver , Möbius‐Winkler Sven , Schulze Paul Christian
Published: September 2021

We describe a case of a 20‐year‐old healthy man developing chest pain and classical symptoms of vaccine reactogenicity 12 h after receiving the first dose of mRNA‐1273 (Moderna). Cardiac troponin T was increased, and subepicardial inflammation and focal contractile dysfunction were detected by cardiac magnetic resonance imaging and echocardiography. We confirmed the diagnosis of acute myocarditis by endomyocardial biopsy demonstrating significant infiltration of monocytes and T lymphocytes. Although we detected IgG against nucleocapsid protein of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) indicating prior infection, the patient repeatedly tested negative for SARS‐CoV‐2 and had been asymptomatic for several months. Furthermore, viral genome analysis of endomyocardial biopsy samples was negative for SARS‐CoV‐2 and other potential cardiotropic viruses. These findings and the strong temporal relation between the vaccination and the symptom onset imply a potential side effect of mRNA‐1273.
Rh(III)‐Catalyzed Selective C7 Halogenation of Indolines
Authors: Manisha  , Gupta Shiv Shankar , Dhiman Ankit Kumar , Sharma Upendra
Published: September 2021

An efficient Rh‐catalyzed catalytic method has been developed for selective C7 halogenation of N‐pyrimidyl indolines with N‐halosuccinimides (Cl, Br, I) to produce corresponding halides in good to excellent yields. The advantages of this strategy include broad substrate scope and excellent regioselectivity for C7 functionalization of indolines and feasibility at gram scale level. Various control experiments have been performed to understand the reaction pathway. Applicability of current methodology has been demonstrated by indole synthesis and post‐transformation of the C7 halogenated indolines into different valuable molecules.
A Study of CexFe1−xO2 as a Reducible Oxide for the Thermal Hydrogen Production from Water
Authors: Al-Taweel Salem , Nadeem M. A. , Idriss Hicham
Published: September 2021

Thermal water splitting over 1550 °C‐reduced CeO2 and Ce0.95Fe0.05O2−δ is studied. Hydrogen production over Ce0.95Fe0.05O2−δ was found to be equal to which is higher than that observed on CeO2. The reaction kinetics for Ce0.95Fe0.05O2−δ is also found to be faster. The oxides are studied by X‐ray diffraction, temperature programmed reduction, and scanning transmission electron microscopy (STEM). XRD results show that Fe is substituted for Ce4+ in the as prepared oxides. Fe3+ cations substitution also decreases the CeO2 crystallites size. Heating to 1100 °C increases their size, although the Fe‐containing oxide still shows smaller crystallites when compared with CeO2 alone. The activation energy for surface reduction of CeO2, extracted from TPR, is found to be slightly higher (1.58 eV) than that of bulk reduction (1.43 eV). While high resolution TEM and electron energy loss spectroscopy before reaction show that Fe cations are homogenously distributed, those after reaction show in addition to the growth of the crystallites size, Fe segregation to the edges of the crystals, although no detachment of Fe oxide particles is seen. The mechanism of water dissociative adsorption and hydrogen re‐combinative desorption is discussed in which the role of Ce–O–Fe sites is considered.
Evolution of Sm‐Doped Fe2O3/CeO2 Oxygen Carriers in Chemical Looping Hydrogen Generation
Authors: Cheng Fang , Yan Aijing , Ma Shiwei , Chen Shiyi , Song Tao , Lu Ping , Xiang Wenguo
Published: September 2021

The Sm‐doped Fe2O3/CeO2 is desirable for chemical looping hydrogen generation (CLHG) owing to its satisfactory oxygen ion conductivity, and the reactivity of Fe2O3/Ce0.8Sm0.2O1.9 (FSDC20) is the highest among the Sm‐doped Fe2O3/CeO2 oxygen carriers with different Sm‐doping amounts. This work is focused on the performance evolution of FSDC20 in CLHG with Fe2O3/CeO2 (FSDC0) as comparison, and the related mechanisms are explored. The results show that the evolution of H2 yield with redox cycles for both samples contain an activation and an attenuation process, and the fourth cycle acts as the demarcation point for FSDC20 before the H2 yield stabilizes. Specifically, the activation mainly lie in the phase transition from Fe3O4 to FeO, and the activation and attenuation processes can be ascribed to the particle microstructure evolution. For the activation process in the first four cycles, the grains on the particle aggregate together, however, with porous structure, and the improved reactivity can be attributed to the enhanced interaction between Fe2O3 and CeO2 as well as the generation of CeFeO3. However, the grains continue to aggregate on a large scale after the fourth cycle, leading to serious sintering and thus the attenuation process.
Effect of Adsorption Structure upon Directional Charge Transfer and Electronic Coupling in a Hybrid Dye Sensitizer based on a Cadmium Sulfide Quantum Dot
Authors: Cui Peng , Zhu Xiaolin , Xue Yuan
Published: September 2021

Dye‐functionalized quantum dots (QDs) show promise for solar photovoltaic and photocatalytic applications. However, the energy conversion efficiencies are very sensitive to the chemical environment at the QD–dye interface, which is dependent upon how the QDs and dye interact. Herein, the effect of different surface orientations for an N749 dye attached to a CdS QD upon QD–dye interactions is investigated. The results reveal that the electronic couplings for binding configurations that involve isothiocyanate anchors are generally larger than those involving carboxylate anchors. Furthermore, for some binding modes, the electronic couplings for hole transfer are comparable to those for electron transfer, implying efficient charge separation at the QD–dye interface and reduced electron–hole recombination within the QD. It is also found that the most stable adsorption geometries for the dye are those with double carboxylate anchors, which exhibit weaker electronic coupling than isothiocyanate anchors and provide favorable energy alignment for hole transfer. Overall, the current computational study reveals some fundamental aspects concerning the relationship between interfacial charge transfer for QD/dye composites and their morphologies, such as the binding geometry of the dye, interfacial energetics and donor–acceptor interactions, which benefits the design of QD‐based nanomaterials for photovoltaic and photocatalytic applications.
Solar Desalination via Multilayers of Transparent Photothermal Fe3O4@Cu2–xS Thin Films
Authors: Lyu Mengyao , Lin Jou , Shi Donglu
Published: September 2021

In contrast to a conventional single layer solar still, herein a multilayer system for solar light harvesting and water evaporation via transparent photothermal thin films is developed. Monodispersed Fe3O4@Cu2–xS nanoparticles are dispersed in a polymer solution and deposited on glass and quartz substrates as transparent thin films. These thin films are optically characterized with strong absorptions in the UV and NIR regions, and high average visible transmittance. The photon energies in the UV/NIR regions are converted to heat increasing the water evaporation rate, while the film high transparency makes it possible for light to pass through many layers for an enlarged solar harvesting surface area. A multilayer photothermal evaporation system (MPTES) is developed for water evaporation experiments using various photothermal films. Water evaporation rates are compared between Fe3O4@Cu2–xS and Fe3O4 against different numbers of layers in the MPTES. The photothermal and optical properties of Fe3O4@Cu2–xS thin films are correlated to the heating behaviors and saltwater evaporation rate. Due to high transparency and strong photothermal effects of the films, water evaporation is significantly enhanced via multilayers. The concept of the multilayer solar still will show promise in water desalination.
Aesthetically Acceptable, Breath Friendly Triboelectric Face Masks: Design, Fabrication, and Its Efficacy
Authors: Santra Pralay K. , Singh Ashutosh Kumar , Kulkarni Giridhar U. , Kundu Suman , Rao Tejaswini S. , Ganesha Mukhesh K.
Published: September 2021

Since the beginning of the COVID‐19 pandemic, several attempts have been made worldwide to control the spread of the virus. It is widely accepted that wearing face masks in public and workplaces suppresses the transmission of the virus. Highly effective face masks, e.g. N95, have a high filtration efficiency but with a large pressure drop, which does not allow one to wear the mask comfortably for long hours. A larger population wearing a moderate efficiency mask can also cut the transmission at large. Herein, mask panels from readily available fabrics are developed, that can generate triboelectricity, which enhances the filtration efficiency by around 18% without compromising the pressure drop—allowing one to wear the mask for an extended period. The unique cup‐shaped design of the mask provides a snug fit with no speech distortion or fogging on the glasses.
Catalytic Upgrading of Bio‐Based 5‐Hydroxymethylfurfural to 2,5‐Dimethylfuran with Non‐Noble Metals
Authors: Zhang Songdang , Liu Yixuan , Yang Song , Li Hu
Published: September 2021

2,5‐Dimethylfuran (DMF) is considered one of the most promising liquid transport fuels due to its high energy density, high boiling point, high octane number, and immiscibility with water. It can be obtained mainly by hydrogenolysis of biomass‐derived 5‐hydroxymethylfurfural (HMF) over metal catalysts. This review describes the latest research progress of developing various non‐noble metal catalytic materials for hydrogenolysis of HMF to produce DMF. The effects of different carriers (e.g., carbon materials, nitrogen‐doped carbon materials, and metal oxides), the bimetallic synergistic effect, and catalyst type on the catalyst activity are systematically introduced. The reaction paths of producing DMF from HMF affected by reaction parameters such as non‐noble metals, hydrogen donors, and temperature are discussed. In addition, potential directions for the large‐scale industrial production and application of DMF are proposed.
Effects of Nafion ionomer content on the performance of membraneless direct formate fuel cells
Authors: Shyu Jin‐Cherng , Wang Yun‐Lin
Published: September 2021

Herein, the performance of alkaline, membraneless, and direct formate fuel cells (DFFCs) in a particular configuration was measured and investigated at various fuel concentrations ranging from 1 to 5 M and fuel flow rates ranging from 1 to 5 mL/min, with anode Nafion ionomer contents of 3.73, 2.49, and 1.87 mg/cm2, at cell temperatures ranging from room temperature to 60℃. An anolyte solution containing potassium formate (HCOOK) and potassium hydroxide (KOH) was fed into the flow field sandwiched between the anode and cathode catalyst layers, while air was forced into the airflow field at a 100‐sccm flow rate as the oxidant. Both Pd and Pt are used as the anode and cathode catalysts, respectively, of the DFFCs with 2‐mg/cm2 identical loading. The results showed that both the open circuit voltage and the maximum power density of the DFFCs were enhanced by reducing the Nafion ionomer content. Besides, feeding the DFFCs with the anolyte containing 3‐M HCOOK in 3‐M KOH yielded the highest cell output. As the DFFCs were fed with the anolyte containing 3‐M HCOOK in 3‐M KOH at 3 mL/min with anode Nafion ionomer content of 1.87 mg/cm2, the peak power density values of the fuel cells at room temperature and 60℃ were 66.24 and 85.60 mW/cm2, respectively.
Simulation of a parabolic trough solar collector containing hybrid nanofluid and equipped with compound turbulator to evaluate exergy efficacy and thermal‐hydraulic performance
Authors: Khetib Yacine , Alahmadi Ahmad , Alzaed Ali , Sharifpur Mohsen , Cheraghian Goshtasp , Siakachoma Cornelius
Published: September 2021

This research is mainly aimed at investigating the numerical modeling of thermal‐hydraulic and exergy efficiencies of parabolic trough solar collectors (P‐SCs) filled with magnetic hybrid nanofluid. The k‐epsilon turbulence, S2S, and mixture models were used to simulate the turbulence equations, radiation, and two‐phase nanofluid, respectively. The experiments were run using magnetic nanofluid in Reynolds numbers of 5000‐20 000, the volume fractions of 1%‐3%, and the ratios of pitch (ROPs) of 1, 2, and 3 of the combined turbulator. According to the results, there is a significant increase in average Nusselt number (Nu) and pressure drop (ΔP) with increasing Reynolds number, nano‐additive concentration, and ROP. Moreover, the use of the hybrid magnetic turbulator and hybrid nanofluid increased the thermal performance of the P‐SC. It was also found that the Reynolds number of 20 000 and volume fraction of 3% of nanoparticles resulted in the optimal exergy efficiency mode in using a hybrid turbulator.
Blockchain and artificial intelligence enabled privacy‐preserving medical data transmission in Internet of Things
Authors: Alzubi Omar A. , Alzubi Jafar A. , Shankar K. , Gupta Deepak
Published: September 2021

Advancements in information technology have benefited the healthcare industry by providing it with distinct methods of managing medical data which improve the quality of medical services. The Internet of Things (IoT) and artificial intelligence are the foundations for innovative sustainable computing technologies in e‐healthcare applications. In the IoT‐enabled sustainable healthcare system, the IoT devices normally record the patient data and transfer it to the cloud for further processing. Security is considered an important issue in the design of IoT networks in the healthcare environment. To resolve this issue, this article presents a novel blockchain and artificial intelligence‐enabled secure medical data transmission (BAISMDT) for IoT networks. The goal of the BAISMDT model is to achieve security and privacy in reliable data transmission of the IoT networks. The proposed model involves a signcryption technique for secure and reliable IoT data transmission. The blockchain‐enabled secure medical data transmission process takes place among the IoT gadgets and service providers. The blockchain technique is applied to generate a viable environment to securely and reliably transmit data among different data providers. Next to the decryption process, the modified discrete particle swarm optimization algorithm with wavelet kernel extreme learning machine model is applied to determine the presence of disease. An extensive set of simulations were carried out on a benchmark medical dataset. The experimental results analysis pointed out the superior performance of the proposed BAISMDT model with the accuracy of 97.54% and 98.13% on the applied Heart Statlog and WBC dataset, respectively.
Characterization of volatile aroma compounds in litchi (Heiye) wine and distilled spirit
Authors: Zhao Lili , Ruan Shili , Yang Xiangke , Chen Qiling , Shi Kan , Lu Ke , He Ling , Liu Shuwen , Song Yangbo
Published: September 2021

This study used litchi (Heiye) wine and distilled spirit as raw experimental materials to analyze the volatile aroma compounds. Qualitative and quantitative determination of aromatic components was studied using stir bar sportive extraction (SBSE) and gas chromatography coupled to mass spectrometry (GC/MS). Results indicated that a total of 128 different types of aroma compounds were observed, which belonged to six chemical groups, including 39 esters, 16 alcohols, 16 acids, 22 terpenes, 17 aldehydes and ketones, and 18 other compounds. In particular, esters were the highest among all six categories and represented approximately 52% of the total flavor component content in litchi distilled spirit. The odor activity values (OAVs) revealed 22 types of aroma compounds with OAVs >1 in this test. It is possible that the produced litchi distilled spirit had a stronger varietal character due to the increased concentrations and OAVs of β‐damascenone, linalool, ethyl butyrate, ethyl isovalerate, ethyl caproate, trans‐rose oxide, and cis‐rose oxide. Taking the OAVs into account, we evaluated the characteristic aromas for litchi wine and litchi distilled spirit.
A proposed lectin‐mediated mechanism to explain the in Vivo antihyperglycemic activity of γ‐conglutin from Lupinus albus seeds
Authors: Grácio Madalena , Rocha João , Pinto Rui , Boavida Ferreira Ricardo , Solas João , Eduardo‐Figueira Maria , Sepodes Bruno , Ribeiro Ana Cristina
Published: September 2021

Experiments conducted in vitro and in vivo, as well as clinical trials for hypoglycemic therapeutics, support the hypoglycemic properties of the lectin γ‐conglutin, a Lupinus seed storage protein, by a mechanism not yet been clarified.

Structural studies established that binding of γ‐conglutin, in native and denatured form, to insulin occurs by a strong binding that resists rupture when 0.4 M NaCl and 0.4 M galactose are present, suggesting that strong electrostatic interactions are involved. Studies on binding of γ‐conglutin in native and denatured form to HepG2 membrane glycosylated receptors were conducted, which reveal that only the native form of γ‐conglutin with lectin activity is capable of binding to these receptors.

Glycosylated insulin receptors were detected on purified HepG2 cell membranes and characterized by 1D and 2D analyses.

Preclinical assays with male mice (CD‐1) indicated that native and denatured γ‐conglutins display antihyperglycemic effect, decreasing glucose in blood comparable after 120 min to that exhibited by the animal group treated with metformin, used to treat T2D and used as a positive control. Measurement of organ injury/functional biomarkers (hepatic, pancreatic, renal, and lipid profile) was comparable to that of metformin treatment or even better in terms of safety endpoints (pancreatic and hepatic biomarkers).
An experimental and numerical study of the exchange current density in an HTPEM fuel cell
Authors: Çelik Murat , Elden Gülşah
Published: September 2021

The purpose of this study is to examine the effects of exchange current density, as dependent on operating parameters, on the activation polarization in an HTPEM fuel cell. In line with this purpose, cell performance tests were performed for different relative humidity levels (from 0 to 20% in steps of 5%) and six different acid doping levels (4.26, 4.53, 4.95, 5.51, 7.24, 7.51 H3PO4/RPU PBI) at constant cell temperature (120 °C). The exchange current densities, as dependent on acid doping level and relative humidity, were determined by fitting a zero‐dimensional steady‐state mathematical model to the cell performance test results. Finally, to investigate the activation polarization in the cell, the exchange current densities obtained were incorporated within a numerical model. The results show that the effects of relative humidity on the exchange current density are relatively limited at all acid doping levels when the relative humidity is greater than 5%. The exchange current densities exhibit a decreasing trend with increasing acid doping level. Furthermore, it was found that the acid doping level and relative humidity have a strong influence on the anode overpotential, whereas no significant effect on the cathode overpotential was observed.
Flint sources and mobility at the Chalcolithic (3500–2200 BCE) settlement of Zambujal (Portugal)
Authors: Jordão Patrícia , Pimentel Nuno
Published: September 2021

Provenance studies of the siliceous sedimentary raw material used by ancient communities are essential to understanding the mobility and exchange networks of these communities. The establishment of the direct procurement territory is the first step to understanding the role of the ‘imported’ artefacts. In this study, flint cores, flakes, bladelets and debitage from the Chalcolithic settlement of Zambujal (Estremadura, Portugal), recovered in excavations between 1964 and 1979, are analysed. We attempt to identify the local and regional source areas of these stone materials and compare their petrography (facies and microfacies textures). This study demonstrates the importance of employing three scales of analysis in petrographic studies (the macro‐, meso‐ and micro‐) to structure and determine flint provenance. Analysis of cortical material shows the relevance of secondary detrital outcrops during the Chalcolithic of the Portuguese Estremadura. Small cobbles were directly collected in both local and regional formations dated to the Palaeogene and Cenomanian, in a large (approx. 40 km) exploration territory, to produce expedient and specialized artefacts (i.e., bladelets). However, a large portion of stone tools from Zambujal made from Cenomanian flint cannot be assigned to local or regional procurement. The unclear provenance of these materials suggests directions for future research.
Macrophages in the cochlea; an immunological link between risk factors and progressive hearing loss
Authors: Hough Kate , Verschuur Carl A. , Cunningham Colm , Newman Tracey A.
Published: September 2021

Macrophages are abundant in the cochlea; however, their role in hearing loss is not well understood. Insults to the cochlea, such as noise or insertion of a cochlear implant, cause an inflammatory response, which includes activation of tissue‐resident macrophages. Activation is characterized by changes in macrophage morphology, mediator expression, and distribution. Evidence from other organs shows activated macrophages can become primed, whereby subsequent insults cause an elevated inflammatory response. Primed macrophages in brain pathologies respond to circulating inflammatory mediators by disproportionate synthesis of inflammatory mediators. This signaling occurs behind an intact blood–brain barrier, similar to the blood‐labyrinth barrier in the cochlea. Local tissue damage can occur as the result of mediator release by activated macrophages. Damage is typically localized; however, if it is to structures with limited ability to repair, such as neurons or hair cells within the cochlea, it is feasible that this contributes to the progressive loss of function seen in hearing loss. We propose that macrophages in the cochlea link risk factors and hearing loss. Injury to the cochlea causes local macrophage activation that typically resolves. However, in susceptible individuals, some macrophages enter a primed state. Once primed, these macrophages can be further activated, as a consequence of circulating inflammatory molecules associated with common co‐morbidities. Hypothetically, this would lead to further cochlear damage and loss of hearing. We review the evidence for the role of tissue‐resident macrophages in the cochlea and propose that cochlear macrophages contribute to the trajectory of hearing loss and warrant further study.
Genome‐Wide Association Study of NAFLD Using Electronic Health Records
Authors: Fairfield Cameron J. , Drake Thomas M. , Pius Riinu , Bretherick Andrew D. , Campbell Archie , Clark David W. , Fallowfield Jonathan A. , Hayward Caroline , Henderson Neil C. , Joshi Peter K. , Mills Nicholas L. , Porteous David J. , Ramachandran Prakash , Semple Robert K. , Shaw Catherine A. , Sudlow Cathie L.M. , Timmers Paul R.H.J. , Wilson James F. , Wigmore Stephen J. , Harrison Ewen M. , Spiliopoulou Athina
Published: September 2021

Genome‐wide association studies (GWAS) have identified several risk loci for nonalcoholic fatty liver disease (NAFLD). Previous studies have largely relied on small sample sizes and have assessed quantitative traits. We performed a case‐control GWAS in the UK Biobank using recorded diagnosis of NAFLD based on diagnostic codes recommended in recent consensus guidelines. We performed a GWAS of 4,761 cases of NAFLD and 373,227 healthy controls without evidence of NAFLD. Sensitivity analyses were performed excluding other co‐existing hepatic pathology, adjusting for body mass index (BMI) and adjusting for alcohol intake. A total of 9,723,654 variants were assessed by logistic regression adjusted for age, sex, genetic principal components, and genotyping batch. We performed a GWAS meta‐analysis using available summary association statistics. Six risk loci were identified (P < 5*10−8) (apolipoprotein E [APOE], patatin‐like phospholipase domain containing 3 [PNPLA3, transmembrane 6 superfamily member 2 [TM6SF2], glucokinase regulator [GCKR], mitochondrial amidoxime reducing component 1 [MARC1], and tribbles pseudokinase 1 [TRIB1]). All loci retained significance in sensitivity analyses without co‐existent hepatic pathology and after adjustment for BMI. PNPLA3 and TM6SF2 remained significant after adjustment for alcohol (alcohol intake was known in only 158,388 individuals), with others demonstrating consistent direction and magnitude of effect. All six loci were significant on meta‐analysis. Rs429358 (P = 2.17*10−11) is a missense variant within the APOE gene determining ϵ4 versus ϵ2/ϵ3 alleles. The ϵ4 allele of APOE offered protection against NAFLD (odds ratio for heterozygotes 0.84 [95% confidence interval 0.78‐0.90] and homozygotes 0.64 [0.50‐0.79]). Conclusion: This GWAS replicates six known NAFLD‐susceptibility loci and confirms that the ϵ4 allele of APOE is associated with protection against NAFLD. The results are consistent with published GWAS using histological and radiological measures of NAFLD, confirming that NAFLD identified through diagnostic codes from consensus guidelines is a valid alternative to more invasive and costly approaches.
Does tourism increase CO2 emissions and health spending in Mexico? New evidence from nonlinear ARDL approach
Authors: Fan Yongxian , Ullah Irfan , Rehman Alam , Hussain Arif , Zeeshan Muhammad
Published: September 2021

This study investigates the nexus between tourism, CO2 emissions and health spending in Mexico. We applied a nonlinear ARDL approach for the empirical analysis for the time period 1996–2018. Mexico receives a large number of tourists each year, tourism improves foreign exchange earnings and contributes positively to the economic growth. However, tourist activities impose a serious environmental cost in terms of CO2 emissions which increase health spending. The empirical findings suggest that tourism leads to CO2 emissions which resultantly causes a high level of health spending in Mexico. Both short‐run and long‐run findings reported a significant positive association between tourism, CO2 emissions, and health expenditures. Therefore, the government needs legislation to reduce CO2 emissions, besides the use of renewable energy could also help to reduce the CO2 emissions and health expenditures in society. This study does not support to reduce the health expenditure, rather it suggests optimal utilization of the funds allocated to the health sector.
Responsiveness of hospitals to inpatient and outpatient services in the low‐ and middle‐income countries: A systematic review
Authors: Shaqura Iyad Ibrahim , Jaafaripooyan Ebrahim , Ahmadi Batoul , Akbari Sari Ali
Published: September 2021

Responsiveness is the ability of health system to satisfy non‐clinical people's expectations. This review aimed at assessing responsiveness of hospitals' services in the low‐ and middle‐income countries, and identifying the influencing factors. This systematic review followed the PRISMA guidelines. PubMed, Scopus, Web of Science and ProQuest were searched. Studies of all designs aiming to assess responsiveness of hospitals' services in the period from 2005 up to the end of 2018 were included. Quality was appraised based on McMaster University tool. Results were presented as a narrative review. Fifteen studies originated from five low‐middle‐ income countries have been included. Results have been proposed under five subtopics; level and distribution of responsiveness and its domains at hospitals, rank of domains according to the participants, and factors affecting responsiveness and its related domains. Most studies have focused on responsiveness level, but not the distribution. Socioeconomic status, organisational, systemic, and contextual factors have led to varied responsiveness, consequently, policymakers would benefit from these valuable results while planning for improving health system in order to accomplish its intrinsic goals. Further research is required in the low‐ and middle‐income countries other than the five included in this review. Using the World Health Organization questionnaires for measuring responsiveness is recommended, and the contextual variations should be considered.
Hepatitis C virus testing in a clinical HIV cohort in Ontario, Canada, 2000 to 2015
Authors: Moqueet Nasheed , Grewal Ramandip , Mazzulli Tony , Cooper Curtis , Gardner Sandra L. , Salit Irving E. , Kroch Abigail , Burchell Ann N. ,   OHTN Cohort Study Team
Published: September 2021

Background

HIV‐positive individuals may acquire HCV via injection drug use (IDU) and condomless anal sex. HIV care provides opportunities for HCV testing and cure with direct‐acting antiviral agents (DAAs).

Methods

We analyzed data from the Ontario HIV Treatment Network Cohort Study. Among those not HCV‐positive or diagnosed previously (n = 4586), we used Cox regression to test the rates of ever HCV testing (serological or RNA) in HIV care by DAA era (pre‐DAA: 2000‐2010; after DAA: 2011‐2015) and compared the proportion diagnosed with HCV. We identified correlates of annual proportions of serological testing using Poisson generalized estimating equations.

Results

After DAA vs pre‐DAA, the hazard rate ratio (95% CI) of ever HCV testing was 1.70 (1.59, 1.81). The proportion (95% CI) tested annually increased from 9.2% (8.0%, 10.7%) in 2000 to 39.1% (37.1%, 41.1%) in 2015 (P < 0.0001). The proportion diagnosed with HCV declined by 74% pre‐DAA to 11% after DAAs. Annual testing increased per calendar year (16% steeper slope after DAA vs pre‐DAA) and was more common among men who have sex with men; those more educated (post‐secondary vs ≤ high school); and those positive for syphilis or reporting any IDU. Annual testing decreased per decade of age and time since HIV diagnosis.

Discussion

Annual HCV testing increased over time with higher testing among those reporting sexual or IDU risk factors, but fell short of clinical guidelines. Targeted interventions to boost testing may be needed to close these gaps and reach WHO 2030 HCV elimination targets.
Effect of digital elevation model spatial resolution on depression storage
Authors: Hou Jingming , Li Xinyi , Pan Zhanpeng , Wang Junhui , Wang Ruike
Published: September 2021

Surface water storage—including wetlands and other small waterbodies—has largely been disregarded in traditional hydrological models. In this paper, the grid resampling method is adopted to study the influence of the digital elevation model (DEM) grid resolution on depression storage (DS) considering different rainfall return periods. It is observed that the DEM grid size highly affects DS, and the higher the grid resolution is, the larger the DS value. However, when the grid resolution reaches a certain value, the maximum DS value decreases. This suggests that a critical grid resolution value exists at which the water storage capacity of depressions is maximized, namely, 20 m in this work (except for the overall area simulation under infiltration). This phenomenon is further verified in two test cases with and without the infiltration process, that is, calculations of the local area and without infiltration area, respectively. This research may facilitate the accurate computation of the DS process, which is greatly affected by the grid resolution, thereby improving the reliability of hydrological models.
Ardières‐Morcille in the Beaujolais, France: A research catchment dedicated to study of the transport and impacts of diffuse agricultural pollution in rivers
Authors: Gouy Véronique , Liger Lucie , Ahrouch Samira , Bonnineau Chloé , Carluer Nadia , Chaumot Arnaud , Coquery Marina , Dabrin Aymeric , Margoum Christelle , Pesce Stéphane
Published: September 2021

The 8‐km2 Morcille catchment, which is a sub‐catchment of the 150‐km2 Ardières catchment in the Beaujolais region of France, is one of the first sites in Europe where research has been conducted on surface water contamination by pesticides. A consolidated hydrological and chemical dataset has been set up with data collected since 2002 on the Morcille River and since 2011 on the Ardières River. Additional data on the ecotoxicological and ecological impacts of pesticides on aquatic microbial communities and macroinvertebrates has also been recorded in both rivers since 2005. The ‘Site Atelier Ardières‐Morcille Dataset’ described here combines rainfall and stream water height measurements at gauged stations with concentrations of two trace elements and nine pesticides (mainly herbicides, fungicides and some of their metabolites) in both the Ardières and Morcille rivers. All contaminant concentration data showed spatial and temporal variability in water quality associated with pesticide use and rainfall patterns. This long‐term monitoring framework made it possible to estimate the persistence of two herbicides (diuron and norflurazon) after legislation banning them. It took 4 years for diuron and more than 10 years for norflurazon concentrations to fall below 0.1 μg/L. Concurrent biological data showed a gradient of impacts consistent with chemical anthropogenic pressure, and rapid recovery of phototrophic microbial communities after the diuron ban. Finally, monitoring data on pesticide transport in a grassed strip set on a slope of the Morcille catchment confirmed that vegetative filter strips can effectively reduce diuron fluxes in surface runoff (>80% abatement) and infiltration water (>70% abatement). The full dataset offers a valuable resource for the validation of hydrological models and the development of global approaches to better understand the pressure–transport–exposure–impact chain and aquatic community resilience at the small catchment scale.
Wnt pathway modulators in cancer therapeutics: An update on completed and ongoing clinical trials
Authors: Neiheisel Ann , Kaur Manpreet , Ma Nancy , Havard Patty , Shenoy Anitha K.
Published: September 2021

Wnt signaling plays an essential role in the initiation and progression of various types of cancer. Besides, the Wnt pathway components have been established as reliable biomarkers and potential targets for cancer therapy. Wnt signaling is categorized into canonical and noncanonical pathways. The canonical pathway is involved in cell survival, proliferation, differentiation and migration, while the noncanonical pathway regulates cell polarity and migration. Apart from its biological role in development and homeostasis, the Wnt pathway has been implicated in several pathological disorders, including cancer. As a result, inhibiting this pathway has been a focus of cancer research with multiple targetable candidates in development. In this review, our focus will be to summarize information about ongoing and completed clinical trials targeting various Wnt pathway components, along with describing current and emerging Wnt targeted therapies. In addition, we will discuss potential opportunities and associated challenges of inhibiting Wnt signaling for cancer therapy.
Low‐dose aspirin use and mortality risk in patients with head and neck cancer: A nationwide cohort study of 10 770 patients
Authors: de la Cour Cecilie D. , von Buchwald Christian , Dehlendorff Christian , Garset‐Zamani Martin , Grønhøj Christian , Carlander Amanda‐Louise F. , Friis Søren , Kjaer Susanne K.
Published: September 2021

Several recent observational studies have linked low‐dose aspirin use to improved survival in patients with head and neck cancer. However, studies of patterns of aspirin use and risk of cancer‐specific mortality are lacking. This nationwide cohort study included all patients in the Danish Cancer Registry with a primary diagnosis of head and neck squamous cell cancer (HNSCC) during 2000 to 2016, aged 30 to 84 years, without prior cancer (except nonmelanoma skin cancer) and alive 1 year after diagnosis. Nationwide registries provided information on filled prescriptions, mortality and potential confounding factors. For a subpopulation, a clinical database provided additional information, including human papillomavirus (HPV) tumor status. We used Cox proportional hazards regression models to estimate adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) for the association between postdiagnostic low‐dose aspirin use (≥1 prescription within first year after diagnosis) and risk of cancer‐specific mortality. We identified 10 770 patients with HNSCC during a median follow‐up of 3.9 years. Of these, 1799 (16.7%) were low‐dose aspirin users. Postdiagnostic use of low‐dose aspirin was associated with a HR of 0.97 (95% CI 0.82‐1.15) for cancer‐specific mortality. Similar neutral associations were found according to patterns of aspirin use. No apparent trends emerged according to age, sex, topography or stage. A tendency towards a decreased cancer‐specific mortality risk with low‐dose aspirin use was observed among HPV‐positive patients; however, the statistical precision was low. In conclusion, we did not observe an association between postdiagnostic low‐dose aspirin use and cancer‐specific mortality in a nationwide cohort of patients with HNSCC.
Childhood cancer drugs in China: An overview and comparison of regulatory approvals in China and the United States
Authors: Zhang Yichen , Katharina Wagner Anita , Du Haoxin , Han Taisen , Gupta Sumit , Denburg Avram E. , Frazier A. Lindsay , Guan Xiaodong , Shi Luwen
Published: September 2021

Different from less developed countries, 80% of children with cancers in the United States are cured. Traditional chemotherapy drugs are the mainstay of therapies; new targeted medications have become available recently. Using publicly available data, we created a database of cancer drugs with paediatric malignancy indications approved by 31 October 2020 in China and the United States. We compared numbers, type, indications and listing on the World Health Organization Model List of Essential Medicines for Children (WHO EMLc) between the two countries, assessed the correlation between paediatric indications and cancer incidences, and described evidence supporting approvals of targeted medications in the two settings. Our study showed that by 31 October 2020, 31 and 39 cancer drugs available in China and the United States were approved for use in children, corresponding to 137 and 102 paediatric cancer indications, respectively. About half of these drugs (17 in China and 18 in the United States) were listed on the WHO EMLc. The correlation between indications and burden of disease was higher in the United States (r = 0.68) than China (r = 0.59). More traditional chemotherapy drugs were approved in China (n = 27) than the United States (n = 19). Of 20 targeted childhood anticancer medicines approved in the United States, mainly on the basis of single arm trials (27/32 indications, 84.4%), only four were approved for paediatric indications in China, at a median of 2.8 years after US Food and Drug Administration approval. A harmonised, evidence‐based regulatory framework is needed to ensure approvals of needed, safe and efficacious childhood cancer drugs across the world.