bluuebunny/crossref_metadata_2025 huggingface dataset:
Carbon Felt Decorated with Carbon Derived from Spent Asphalt as a Low‐cost and High‐performance Electrode for Vanadium Redox Flow Batteries
Authors: Xu Zhizhao , Xu He , Hu Zhengyu , Wu Wenze , Xu Jian , Zhong Fangfang , Ding Mei , Zhu Xiaobo , Fu Hongyuan , Jia Chuankun
Published: February 2022

Vanadium redox flow batteries (VRFBs) have attracted much attention in the field of energy storage systems owing to their safety, long‐cycle life, and feasible scalability. However, the market penetration of VRFBs is still hindered by the poor performance of current carbon‐based electrodes. Herein, spent asphalt is employed as an efficient and low‐cost precursor to generate carbon decorating carbon felt for VRFB applications. By thermal decomposition treatment, the spent asphalt is converted into highly active pyrolytic carbon and deposited on surfaces of carbon felt. The as‐prepared carbon felt with increased active sites and improved hydrophility displays superior performance towards redox reactions of VO2+/VO2+ in terms of better electrochemical reversibility and faster reaction kinetics. Therefore, the VRFB cell with the carbon felt decorated with carbon derived from spent asphalt as cathode shows 85% energy efficiency which is higher than the pristine carbon felt cathode by 9%. Meanwhile, the energy efficiency and voltage efficiency are both stable during the cell cycling. This strategy can raise the value of the spent asphalt and improve the performance of VRFBs with the decorated carbon felt electrode shedding light on their commercial applications for large‐scale energy storage.
Reconfigurable Origami Transparent Cellulose Triboelectric Paper for Multi‐modal Energy Harvesting
Authors: Xiong Jiaqing , Li Yi , Gao Dace , Chen Jian , Parida Kaushik , Lee Pooi See
Published: February 2022

Facile integration of foldability, transparency, and waterproofness in multi‐modality triboelectric nanogenerator (TENG) applications is interesting. Here, we realized a reconfigurable origami transparent cellulose electronic paper (CEP) as TENG for energy harvesting from water, wind, and human motion. A unique silver nanowires‐bundle mesh (AgBM) was embedded into a micron‐thick ethyl cellulose paper by spraying and transfer process. Operating in single‐electrode mode, the CEP‐TENG can harvest energy from human motions by tapping, scavenge wind energy via mechanical interaction, as well as harvest energy from water, including acidic and alkaline water in virtue of protection by an extra hydrophobic cellulose oleoyl ester nanocoating. Origami capability enables the CEP‐TENG to be reconfigurable in three‐dimensional mode to maximize the energy harvesting efficiency. The CEP‐TENG energy window was demonstrated under the flowing water to achieve a self‐powered lighting display. CEP‐TENG realizes the all‐weather and multi‐modality energy harvesting, promising for wearable and attachable power sources, self‐powered applications such as outdoor displays, windows, decorative accessories, and life‐saving appliances.
Surface Modification of Porous Silica Particles with Carbohydrate Scaffolds as Receptor Components for Molecular Recognition
Authors: Uchida Tsukasa , Nakamura Ayano , Shimazaki Hannah , Kanie Yoshimi , Kanie Osamu
Published: February 2022

Biosensors play a pivotal role in diagnosis through specific receptor‐ligand interactions. However, receptor biomolecules such as proteins have inevitable stability issues due to denaturation. Alternatively, utilization of the small molecules multivalently presented on porous silica particles as receptor components is considered to address the stability issues. A series of receptor components was synthesized using carbohydrates as a chiral scaffold to support multiple functional groups. The synthesized molecules were attached on the porous silica particles. Raman spectral analyses of single silica particles in the presence of nitrobenzene derivatives revealed a specific interaction with 4‐nitrophenol among others using a confocal Raman microscope. Chiral selective recognition was also accomplished for (1S,3S)‐ and (1R,3R)‐2‐amino‐1‐(4‐nitrophenyl)‐1,3‐propanediols. Protected carbohydrate derivatives are shown to be useful as receptor components on porous silica particles.
Oxetane Monomers Based On the Powerful Explosive LLM‐116: Improved Performance, Insensitivity, and Thermostability
Authors: Born Max , Karaghiosoff Konstantin , Klapötke Thomas M. , Voggenreiter Michael
Published: February 2022

3‐Bromomethyl‐3‐hydroxymethyloxetane represents an inexpensive and versatile precursor for the synthesis of 3,3‐disubstituted oxetane derivatives. In the present work, its synthesis was improved and energetic oxetanes based on the explosive LLM‐116 (4‐amino‐3,5‐dinitro‐1H‐pyrazole) prepared. Reaching detonation velocities and pressures of up to 7335 ms−1 and 20.9 GPa in combination with a high thermostability and insensitivity, these surpass the prior art by far. Next to a symmetric LLM‐116 derivative, three asymmetric compounds were prepared using azido‐, nitrato‐ and tetrazolyl‐moieties. All compounds were intensively characterized by vibrational‐, mass‐ and multinuclear (1H, 13C, 14N) NMR spectroscopy, differential scanning calorimetry and elemental analysis. The molecular structures were elucidated by single crystal X‐ray diffraction. Hirshfeld analysis allowed to estimate their sensitivity next to a practical evaluation using BAM standard procedures. Their performance was calculated using the EXPLO5 V6.04 code and a small‐scale shock reactivity test and initiation test demonstrated their insensitivity and performance.
Characteristics of post‐traumatic embitterment disorder of inpatients in a general hospital in China
Authors: Gao Yuting , Wang Xiaoyan , Tan Liangliang , Yang Ting , Shi Linhua , Chen Huanxin , Jiang Wenhao , Yuan Yonggui
Published: February 2022

Objective

Embitterment and post‐traumatic embitterment disorder (PTED) is critical, merging through different cultures. We explored the prevalence and related clinical characteristics of PTED of inpatients in a general hospital in China.

Method

Two hundred inpatients (aged 18–65 years) from different departments were recruited by convenient sampling and standardized diagnostic interviews of PTED. Demographic data, Post‐traumatic Embitterment Disorder Self‐Rating Scale (PTED‐21), the Patient Health Questionnaire depression scale (PHQ‐9), Generalized Anxiety Disorder‐7 (GAD‐7) and the Patient Health Questionnaire depression scale (PHQ‐15) were collected on all participants.

Results

The prevalence of PTED was 21% (42/200) in inpatients in China; besides, the rate of increased syndromal embitterment is 28% (56/200), including 42 patients diagnosed with PTED. PTED was mainly associated with stressful events, such as illness, work and complicated interpersonal relationships. Rheumatology department and respiratory department have the highest and second highest prevalence of PTED among all departments. PTED‐21 scores were significantly correlated with PHQ‐9, GAD‐7 and PHQ‐15 (all P < 0.01).

Conclusions

The present study shows that embitterment is a critical negative emotion in inpatients with somatic illnesses with comorbid depression, anxiety and somatic symptoms. PTED and feelings of embitterment should be given proper attention in diagnosing somatic patients, and it is crucial to enhance PTED screening and intervention in the future. Future intervention studies on post‐traumatic embitterment disorder could be done in general and especially in psychosomatic and somatic medicine.
Matrix Effects on Photoluminescence and Oxygen Sensitivity of a Molecular Ruby
Authors: Wang Cui , Kitzmann Winald R. , Weigert Florian , Förster Christoph , Wang Xifan , Heinze Katja , Resch‐Genger Ute
Published: February 2022

The molecular ruby analogue [Cr(ddpd)2]3+ (ddpd=N,N’‐dimethyl‐N,N’‐dipyridine‐2‐ylpyridine‐2,6‐diamine) exhibits near infrared (NIR) emission with a high photoluminescence (PL) quantum yield ΦPL of 11 % and a lifetime of 898 μs in deaerated water at room temperature. While ligand‐based control of the photophysical properties has received much attention, influences of the counter anions and microenvironment are still underexplored. In this study, the luminescence properties of the molecular ruby were systematically examined for the counter anions Cl−, Br−, [BF4]−, [PF6]−, [BPh4]−, and [BArF24]− in acetonitrile (MeCN) solution, in crystals, and embedded into polystyrene nanoparticles (PSNP). Stern‐Volmer analyses of the oxygen quenching studies in the intensity and lifetime domain showed the highest oxygen sensitivity of the complexes with the counter anions of [BF4]− and [BArF24]−, which also revealed the longest luminescence lifetimes. Embedding [Cr(ddpd)2][PF6]3 in PSNPs and shielding with poly(vinyl alcohol) yields a strongly NIR‐emissive oxygen‐insensitive material with a record ΦPL of 15.2 % under ambient conditions.
Step Evolution and Growth Rate on {101} Faces of Potassium Dihydrogen Phosphate Crystals Grown at High Supersaturation
Authors: Liu Hui , Li Weidong , Wang Shenglai
Published: February 2022

The surface micromorphology of the {101} faces of potassium dihydrogen phosphate (KDP) crystals grown at different supersaturation conditions is systematically compared using atomic force microscopy. The height and width of the crystals during different growth steps are measured. The pyramidal face growth rate of KDP crystals is tested by a laser polarization interference system. The X‐ray rocking curve is used to measure the structural perfection of the {101} face of the KDP crystals. The results show that the growth rate of the {101} face increases with the supersaturation degree, and the rate is faster than that of the {100} face at a low supersaturation degree. Step bunching first increases and then decreases upon increasing the supersaturation, and the step height reaches a maximum value of about 6.0–6.9 nm at σ = 0.08 and 0.09. The crystal structural perfection is the worst under these conditions. It should be noted that 2D nuclei form on the surface terraces when the supersaturation is about 0.07. Dendrite‐like steps may be formed due to the development of these 2D nuclei. This work provides a reference for further researching the step evolution law of other crystalline materials.
Comparison of internal fit of metal‐ceramic crowns in CAD/CAM and lost‐wax techniques in all fabrication stages through replica weighting, triple scanning, and scanning electron microscope
Authors: Sadr Sina Mohammadi , Ahmadi Elham , Tabatabaei Masoumeh Hasani , Mohammadi Saba , Atri Faezeh
Published: February 2022

Objectives

Restoration fit is one of the prerequisites of clinical durability. It is controversial as to whether computer‐assisted design/computer‐aided milling (CAD/CAM) or lost‐wax fabrication methods result in more fit metal‐ceramic crowns. This in‐vitro study was conducted to examine the internal fit of porcelain fused to metal crowns fabricated using CAD/CAM and lost‐wax techniques during fabrication stages (framework, porcelain, cementation) through digital triple scanning, replica weighting, and observation with electron microscopy.

Material and methods

Twenty uniform resin dies of prepared first maxillary molars were randomly divided into two groups according to the fabrication technique: lost wax and CAD/CAM. The internal fit was measured in all steps of completing the crowns (framework, porcelain, and cementation) using different methods, including triple scanning, replica weighting, and scanning electron microscopy. The data were statistically analyzed using t test, Pearson, and repeated measures analysis of variance (α = .05).

Results

Triple scanning revealed no difference in the internal fit of CAD/CAM and lost‐wax groups in all the fabrication steps (p > .05). The replica weighting method showed no difference between groups in the framework step (p > .05), while the internal fit was significantly better in the CAD/CAM group after porcelain application (p < .05). After cementation, electron microscopy measurements showed no difference between CAD/CAM and lost wax groups (p > .05). The Pearson correlation test showed no significant correlation between electron microscopy, replica weighing, and triple scanning methods (p > .05).

Conclusion

According to scanning electron microscopy as the superior evaluation method, the internal fit of cobalt–chrome PFM crown of both CAD/CAM and lost wax groups was within the acceptable clinical range and there was no significant difference between them. Triple scanning revealed no difference in the internal fit of framework and porcelain steps but a better fit after cementation. According to replica weighting, the internal fit in the porcelain step was higher than the framework.
A non‐isolated high voltage gain DC–DC converter based hybrid switched LC network for renewable energy applications
Authors: Alsolami Mohammed , Allehyani Ahmed
Published: February 2022

This paper presents a new high voltage gain DC–DC converter for renewable energy applications without the need for a galvanic isolation. The converter combines the active switched‐inductor network and the switched‐capacitor network to boost the voltage gain ratio without a high duty ratio. The presented converter uses clamping capacitors to minimize the maximum voltage stress of the power‐switching devices; hence, low power rating devices can be employed. Furthermore, the converter operates at a high switching frequency. Therefore, the use of small inductors and capacitors is the main advantage. The paper describes in detail the operating mode and design procedures of the converter. Additionally, the associated power losses and the efficiency are calculated. A 200‐W laboratory prototype was fabricated, and experimental results verified the theoretical analysis.
Quantitative determination of five cannabinoids in blood and urine by gas chromatography tandem mass spectrometry applying automated on‐line solid phase extraction
Authors: Frei Priska , Frauchiger Stephanie , Scheurer Eva , Mercer‐Chalmers‐Bender Katja
Published: February 2022

Cannabis is the most frequently consumed illegal substance worldwide. More recently, an increasing number of legal cannabis products low in psychoactive Δ9‐tetrahydrocannabinol (THC) but high in non‐intoxicating cannabidiol (CBD) are being more widely consumed. While the detection and quantification of THC and its metabolites in biological matrices is an important forensic‐toxicological task, additional detection of CBD is also important, for example, when examining the plausibility of consumer's statements. This report describes the method validation for the quantitative determination of THC and its two major metabolites, 11‐hydroxy‐THC (OH‐THC) and 11‐nor‐9‐carboxy‐THC (THC‐COOH), as well as CBD and cannabinol (CBN) in whole blood and urine. The method employs automated on‐line solid phase extraction coupled to gas chromatography tandem mass spectrometry (GC–MS/MS). The method was fully validated according to guidelines of the Swiss Society of Legal Medicine (SGRM) and the Society of Toxicological and Forensic Chemistry (GTFCh). The method fulfilled the validation criteria regarding analytical limits, accuracy and precision, extraction efficacy, and sample stability. The limits of detection (LODs) in whole blood and urine were 0.15 ng/mL for THC, OH‐THC and CBD, 0.1 ng/mL for CBN, and 1.0 ng/mL for THC‐COOH. The limits of quantification (LOQ) in whole blood and urine were 0.3 ng/mL for THC, OH‐THC and CBD, 0.2 ng/mL for CBN, and 3.0 ng/mL for THC‐COOH. The fully validated and automated method allows sensitive and robust measurement of cannabinoids in whole blood and urine. Detection of CBD provides additional information regarding consumed products.
Edge disturbance shapes liana diversity and abundance but not liana‐tree interaction network patterns in moist semi‐deciduous forests, Ghana
Authors: Ofosu‐Bamfo Bismark , Addo‐Fordjour Patrick , Belford Ebenezer J.D.
Published: February 2022

Edge disturbance can drive liana community changes and alter liana‐tree interaction networks, with ramifications for forest functioning. Understanding edge effects on liana community structure and liana‐tree interactions is therefore essential for forest management and conservation. We evaluated the response patterns of liana community structure and liana‐tree interaction structure to forest edge in two moist semi‐deciduous forests in Ghana (Asenanyo and Suhuma Forest Reserves: AFR and SFR, respectively). Liana community structure and liana‐tree interactions were assessed in 24 50 × 50 m randomly located plots in three forest sites (edge, interior and deep‐interior) established at 0–50 m, 200 m and 400 m from edge. Edge effects positively and negatively influenced liana diversity in forest edges of AFR and SFR, respectively. There was a positive influence of edge disturbance on liana abundance in both forests. We observed anti‐nested structure in all the liana‐tree networks in AFR, while no nestedness was observed in the networks in SFR. The networks in both forests were less connected, and thus more modular and specialised than their null models. Many liana and tree species were specialised, with specialisation tending to be symmetrical. The plant species played different roles in relation to modularity. Most of the species acted as peripherals (specialists), with only a few species having structural importance to the networks. The latter species group consisted of connectors (generalists) and hubs (highly connected generalists). Some of the species showed consistency in their roles across the sites, while the roles of other species changed. Generally, liana species co‐occurred randomly on tree species in all the forest sites, except edge site in AFR where lianas showed positive co‐occurrence. Our findings deepen our understanding of the response of liana communities and liana‐tree interactions to forest edge disturbance, which are useful for managing forest edge.
Intrinsic Mechanisms of Morphological Engineering and Carbon Doping for Improved Photocatalysis of 2D/2D Carbon Nitride Van Der Waals Heterojunction
Authors: Zhang Jinqiang , Zhao Xiaoli , Chen Lin , Li Shuli , Chen Haijun , Zhu Yuezhao , Wang Shuaijun , Liu Yang , Zhang Huayang , Duan Xiaoguang , Wu Mingbo , Wang Shaobin , Sun Hongqi
Published: February 2022

Van der Waals (VDW) heterojunctions in a 2D/2D contact provide the highest area for the separation and transfer of charge carriers. In this work, a top‐down strategy with a gas erosion process was employed to fabricate a 2D/2D carbon nitride VDW heterojunction in carbon nitride (g‐C3N4) with carbon‐rich carbon nitride. The created 2D semiconducting channel in the VDW structure exhibits enhanced electric field exposure and radiation absorption, which facilitates the separation of the charge carriers and their mobility. Consequently, compared with bulk g‐C3N4 and its nanosheets, the photocatalytic performance of the fabricated carbon nitride VDW heterojunction in the water splitting reaction to hydrogen is improved by 8.6 and 3.3 times, respectively, while maintaining satisfactory photo‐stability. Mechanistically, the finite element method (FEM) was employed to evaluate and clarify the contributions of the formation of VDW heterojunction to enhanced photocatalysis, in agreement quantitatively with experimental ones. This study provides a new and effective strategy for the modification and more insights to performance improvement on polymeric semiconductors in photocatalysis and energy conversion.
Fathead Minnows Exposed to Organic Compounds from Oil Sands Tailings as Embryos Have Reduced Survival, Impaired Development, and Altered Behaviors That Persist into Larval Stages
Authors: Reynolds Jessie S. , Jackson Brianna L. , Madison Barry N. , Elvidge Chris K. , Frank Richard A. , Hasler Caleb T. , Headley John V. , Hewitt L. Mark , Peru Kerry M. , Yakimowski Sarah B. , Orihel Diane M.
Published: February 2022

Our study evaluated whether exposure to naphthenic acid fraction compounds (NAFCs) extracted from oil sands process–affected waters (OSPW) has adverse effects on fish embryos that persist into later life. We exposed fathead minnow (Pimephales promelas) embryos to concentrations of NAFCs found in OSPW (2.5–54 mg/L) for 7 days (1 day postfertilization to hatch), then raised surviving larvae in outdoor mesocosms of uncontaminated lake water for 1 month. Embryos exposed to NAFCs were more likely to exhibit malformations (by up to 8-fold) and had slower heart rates (by up to 24%) compared to controls. Fish raised in uncontaminated lake water following exposure to NAFCs as embryos, were 2.5-fold less likely to survive during the larval stage than control fish. These fish also showed up to a 45% decrease in swim activity and a 36% increase in swim burst events during behavioral tests relative to controls. We conclude that exposure to NAFCs during the embryonic stage can have lasting effects on fish survival, physiology, and behavior that persist at least through the larval stage. These findings of delayed mortalities and persistent sublethal effects of embryonic NAFC exposure are relevant to informing the development of regulations on treated OSPW releases from mining operations. Environ Toxicol Chem 2022;41:1319–1332. © 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Abstract

Embryonic exposure of fathead minnows (Pimephales promelas) to naphthenic acid fraction components derived from oil sands tailings in a seminatural setting had adverse effects on survival, development, and behavior that persisted into larval stages. NAFC = naphthenic acid fraction component.
Control of sedimentary environment on the lithofacies of lacustrine fine‐grained sedimentary rocks in the second member of the Kongdian Formation in the Cangdong sag, Bohai Bay Basin, China
Authors: Fang Zheng , Chen Shiyue , Pu Xiugang , Yan Jihua , Chen Xingran
Published: February 2022

The thick fine‐grained sedimentary rocks in the second member of the Kongdian Formation (Ek2) in the Cangdong sag, Bohai Bay Basin, eastern China, are typical lacustrine source rocks and have recently been regarded as the main target for shale oil exploration. Compared with marine shales, the strong heterogeneity in the mineral composition, structure feature, and vertical association pattern of the Ek2 lacustrine fine‐grained sedimentary rocks in the Cangdong sag is significantly influenced by frequent variations in the sedimentary environment and depositional process. Based on the detailed core and thin‐section description analyses as well as the two‐dimensional X‐ray fluorescence (2D‐XRF) analysis, the Ek2 fine‐grained sedimentary rocks in the Cangdong sag can be classified into six types of lithofacies by employing the content of three main mineral compositions together with structure features, among which five types are mainly deposited, including laminated felsic fine‐grained sedimentary rocks, laminated and massive carbonate fine‐grained sedimentary rocks, and laminated and massive mixed fine‐grained sedimentary rocks. The sedimentary environment during the sedimentary period of the Ek2 in the Cangdong sag was reconstructed by several indexes (including salinity, water depth, redox condition, climate, and detrital input) using the element geochemical parameters. The variations of detrital input and lake physicochemical characteristics driven by climate were vertically divided into four phases, indicating that the lake gradually changed from the transgression to the highstand period. In addition, the water column stratification led to the overall dysoxic–anoxic condition. The depositional process can be interpreted by correlating the lithofacies and the sedimentary environment. The results indicate that the mineral composition is controlled by the detrital input and carbonate production driven by climate and that structural features are mainly affected by the water column stratification. The Ek2 fine‐grained sedimentary rocks in the Cangdong sag present the vertical distribution of lithofacies that matches with the evolution phases of the sedimentary environment. This study's results enhance the understanding of the formation mechanism of lacustrine fine‐grained sedimentary rocks and provide basic geological knowledge for shale oil exploration in the study area.
Competition and efficiency in repeated procurements: Lessons from the Finnish rehabilitation markets
Authors: Pitkänen Visa
Published: February 2022

Inefficient practices and lack of competition are common problems in public procurements. In this study, I examine the effects of a procurement practice reform in the Finnish rehabilitation markets where providers are acquired in a repeated manner through competitive bidding scoring auctions. Until recently, the largest public procurer did not use any systematic criteria for accepting providers, and only a few providers did not receive a contract. After the reform, providers were systematically accepted based on their capacity and the local demand. I analyze the effects of the reform on prices in physio, speech and occupational therapy services with data that covers five subsequent procurements. I use the pre‐reform differences in local competition within the markets in a difference‐in‐differences setting. The descriptive evidence shows that the reform slowed down the rapid increase of prices in all three services. The regression analysis indicates that effects are strongest in the most competitive local physiotherapy markets. This suggests that increasing entry and competition in the less competitive services and local markets would benefit the public procurer.
A case of transvaginal lithotripsy for a giant vaginal calculus
Authors: Owa Shunsuke , Yonemura Shigenori , Sakurai Masaki , Inoue Takahiro
Published: February 2022

Introduction

Primary vaginal calculi are relatively rare, compared with secondary calculi. Primary calculi are often a result of urogenital sinus abnormalities, neurogenic bladder, or chronic incontinence.

Case presentation

Forty‐seven years old female with cerebral palsy since infancy had longstanding urinary incontinence. She visited her doctor for a fever and was referred to us with a urinary tract infection. Imaging revealed a large vaginal calculus. It was not possible to remove the calculus vaginally without crushing it, so we performed rigid cystoscopy with lithotripsy, using a pneumatic lithotripsy device. The calculus was completely removed without complications.

Conclusion

We were able to remove a large primary vaginal calculus using ultrasonic and pneumatic lithotripsy through a rigid cystoscope. Minimally invasive surgery is a good option for patients with large vaginal calculi.
From Considerate to Challenging Texts: A Four‐Tiered Text Approach to Thematic Reading
Authors: Choi Minkyung , Todaro Joseph N.
Published: February 2022

College students are expected to comprehend, analyze, and respond to texts that are often challenging, complex, and specialized. While the importance and value of reading in higher education is hardly disputed, postsecondary literacy frequently revolves around the reinforcement of rudimentary skills. Furthermore, the demands of writing instruction often push reading instruction to the side, leaving students to navigate texts on their own. Challenging texts necessitate a degree of background knowledge, without which active and robust engagement cannot be expected. By scaffolding texts in a way that progressively builds background knowledge, instructors can prepare students for complex texts and subsequently, academic discourse. The authors propose a four‐tiered approach to reading instruction for adult learners that consists of four text types: foundational, expansion, opposing point‐of‐view, and expert’s point‐of‐view. While designed for integrated reading and writing courses, the proposed model has implications for faculty across the disciplines.
Distributions for time, interspecies and intraspecies extrapolation for deriving occupational exposure limits
Authors: Dilger Marco , Schneider Klaus , Drossard Claudia , Ott Heidi , Kaiser Eva
Published: February 2022

This work aimed at improving the empirical database of time (i.e., exposure duration), interspecies and intraspecies extrapolation when deriving occupational exposure limits (OELs). For each extrapolation step, a distribution was derived, which can be used to model the associated uncertainties. For time and interspecies extrapolation, distributions of ratios of dose descriptors were derived from studies of different length or species. National Toxicology Program (NTP) study data were manually assessed, and data from REACH (Registration, Evaluation and Authorisation of Chemicals) registration dossiers were evaluated semi‐automatically. Intraspecies extrapolation was investigated by compiling published studies on human toxicokinetic and toxicodynamic variability. A new database was established for toxicokinetic differences in interindividual susceptibility, including many inhalation studies. Using NTP data produced more reliable results than using REACH data. The geometric mean (GM) for time extrapolation subacute/chronic agreed with previous evaluations (GM = 4.11), whereas the GM for subchronic/chronic extrapolation was slightly higher (GM = 2.93) than the GMs found by others. No significant differences were observed between systemically and locally acting substances. Observed interspecies differences confirmed the suitability of allometric scaling, with the derived distribution describing remaining uncertainty. Distributions of intraspecies variability at the 1% and 5% incidence level had medians of 7.25 and 3.56, respectively. When compared with assessment factors (AFs) currently used in the EU, probabilities that these AFs are protective enough span a wide range from 10% to 95%, depending on the extrapolation step. These results help to select AFs in a transparent and informed way and, by allowing to compare protection levels achieved, to harmonise methods for deriving OELs.
Derivation of occupational exposure limits: Differences in methods and protection levels
Authors: Schneider Klaus , Dilger Marco , Drossard Claudia , Ott Heidi , Kaiser Eva
Published: February 2022

Frameworks for deriving occupational exposure limits (OELs) and OEL‐analogue values (such as derived‐no‐effect levels [DNELs]) in various regulatory areas in the EU and at national level in Germany were analysed. Reasons for differences between frameworks and possible means of improving transparency and harmonisation were identified. Differences between assessment factors used for deriving exposure limits proved to be one important reason for diverging numerical values. Distributions for exposure time, interspecies and intraspecies extrapolation were combined by probabilistic methods and compared with default values of assessment factors used in the various OEL frameworks in order to investigate protection levels. In a subchronic inhalation study showing local effects in the respiratory tract, the probability that assessment factors were sufficiently high to protect 99% and 95% of the target population (workers) from adverse effects varied considerably from 9% to 71% and 17% to 87%, respectively, between the frameworks. All steps of the derivation process, including the uncertainty associated with the point of departure (POD), were further analysed with two examples of full probabilistic assessments. It is proposed that benchmark modelling should be the method of choice for deriving PODs and that all OEL frameworks should provide detailed guidance documents and clearly define their protection goals by stating the proportion of the exposed population the OEL aims to cover and the probability with which they intend to provide protection from adverse effects. Harmonisation can be achieved by agreeing on the way to perform the methodological steps for deriving OELs and on common protection goals.
The effects of thymoquinone and quercetin on the toxicity of acrylamide in rat glioma cells
Authors: Kacar Sedat , Sahinturk Varol , Tomsuk Ozlem , Kutlu Hatice M.
Published: February 2022

Acrylamide is a neurotoxic agent forming in foods. Thymoquinone and quercetin are plant‐derived antioxidants in various foods with known benefits. C6 cells are glioblastoma cells. In this study, we aimed at preventing acrylamide toxicity by thymoquinone and quercetin in the C6 cell line. In our study, first, toxic doses of acrylamide, nontoxic doses of thymoquinone and quercetin in C6 cells for 24 h were determined by MTT (3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5 diphenyl tetrazolium bromide) colorimetric test. After that, caspase 3/7 and annexin V tests were performed by flow cytometry to evaluate whether the apoptosis pathway was inducted. Furthermore, autophagy and oxidative stress were assessed by flow cytometry. The amount of Nrf2 (nuclear factor erythroid 2‐related factor 2) was determined by immunocytochemistry. The morphological examination was performed by microscopic analyses. As a result, 4 mM of acrylamide was determined to be used to induce toxicity in C6 cells. The nontoxic doses of thymoquinone and quercetin were respectively determined as 3.9 and 2.0 µM. Thymoquinone and quercetin not only reduced acrylamide‐induced apoptosis in annexin V and caspase 3/7 assays but also morphological deformations in microscopic examinations. In autophagy, it was revealed that acrylamide‐induced autophagy was decreased by quercetin and thymoquinone pretreatments. As for Nrf2 expression, it was observed that acrylamide increased Nrf2 expression, and thymoquinone and quercetin pretreatments increased it even further. In conclusion, in the study, acrylamide demonstrated a damaging effect on C6 glioblastoma cells, and thymoquinone and quercetin pretreatments exerted a protective effect against acrylamide‐induced damage in C6 cells.
Phenotypes of mutations related to voltage‐dependent sodium channels on children and adolescents
Authors: Ferreira Andressa Coelho , Dias‐Filho Carlos Alberto Alves , de Jesus Silva Soares Junior Nivaldo , Dias Carlos José , Monteiro Sally Cristina Moutinho , Andrade Rafael Martins , Mostarda Cristiano Teixeira
Published: February 2022

Cardiac channelopathies are a heterogeneous group of inherited cardiac diseases that are associated with mutations in the genes that encode the expression of cardiac ion channels. In view of this, it can be mentioned that the main hereditary arrhythmias in children and adolescents, caused by dysfunction of the ion channels, are Brugada Syndrome (BrS) and Long QT Syndrome (LQTS). However, few studies address the physiological effects of these conditions on children and adolescents. Thus, the aim of this study is to describe the mutation phenotype related to voltage‐gated sodium channels in children and adolescents. A search was performed in the literature of PubMed, Scielo, and Google scholar. The search was limited to articles written in the last 5 years, so articles published between 2014 and 2019 were included. Among 2196 studies identified through a systematic literature review, 30 studies related to the theme were identified for a complete review and after applying exclusion criteria, 4 articles were included in the results of this study. As the most frequently observed channelopathy, BrS was also more identified in children and adolescents, characterized by episodes of syncope or sudden cardiac death. LQTS shows clinical manifestations with a mild phenotype and good prognosis, although it is necessary to monitor and correct serum electrolyte disturbances to prevent ventricular arrhythmias and, consequently, sudden death in patients with the pathology. The aim of this study is to find the general phenotypes related to genetic mutations of voltage‐gated sodium channels, in a population aged from 7‐ to 14‐year‐old.
Studies on male gonadal toxicity of bisphenol A in diabetic rats: An example of exacerbation effect
Authors: Sahu Chittaranjan , Singla Shivani , Jena Gopabandhu
Published: February 2022

Bisphenol A (BPA), a widely used organic synthetic chemical alters spermatogenesis and is a potential risk factor for male infertility. Diabetes‐induced hyperglycemia has a negative impact on different vital organs including the testis. However, the effect of BPA on male fertility and gonadal development in diabetic (DIA) patients is unknown. This study explores the role of BPA exposure on testicular toxicity in a DIA rat. The DIA condition in male Sprague–Dawley (SD) rats (4 weeks aged) was induced with the administration of a single dose of streptozotocin (55 mg/kg ip, in cold citrate buffer pH 4.5). BPA was administered orally at the dose of 40 mg/kg/day for 4 consecutive weeks. Various endpoints of the toxicity include biochemical estimations, histological evaluations, oxidative stress parameters, DNA damage assays (apoptosis and endonuclease III), expressions of 8‐hydroxy‐2ʹ‐deoxyguanosine (8‐OHdG), nuclear factor‐erythroid 2‐related factor 2 (Nrf‐2), catalase, superoxide dismutase 1 (SOD‐1), octamer‐binding transcription factor 4 (OCT4), and Sirtulin (silent mating type information regulation 2 homolog) 1 (SIRT 1). The results confirmed that BPA exacerbated the testicular toxicity by altering several biochemical parameters, increasing oxidative stress, cellular/tissue injury, DNA damage, apoptosis, and 8‐OHdG expression, while decreasing the levels of Nrf‐2, catalase, SOD‐1, OCT4, and SIRT1 expressions in the testes of DIA rat. Linear regression analyses indicated a positive correlation between apoptosis and 8‐OHdG, OCT4, and DNA damage (nuclear diffusion factor and tail length). The present study confirmed that BPA exposure in DIA conditions exacerbated the testicular damages in SD rats. Therefore, the DIA condition might have increased male gonadal toxicity due to BPA exposure and requires further attention to maintain their normal reproductive health.
Occupational health intervention for work–life balance and burnout management among teachers in rural communities
Authors: Ogakwu Nneka Vera , Ede Moses Onyemaechi , Amaeze Fidelis E. , Manafa Ifeyinwa , Okeke Francisca Chinwendu , Omeke Faith , Amadi Kingsley , Ede Augustina O. , Ekesionye Ngozi E.
Published: February 2022

This study examined the efficacy of the occupational health model of rational emotive behavioral on work–life balance (WLB) and burnout management (BOM) among public school teachers. The study was a pretest–posttest randomized control group design. The participants were 141 teachers in rural communities in Enugu state Nigeria drawn with emphasis on inclusion criteria. Two instruments were used for the data. Data were analyzed using repeated measure analysis of variance. The result showed that rational emotive occupational health coaching (REOHC) led to a significant increase in the management of WLB and burnout among teachers compared to their counterparts in the control group. At the follow‐up stage, REOHC proved to be effective over a period of 3 months. REOHC is a therapeutic intervention strategy that is valid and reliable over time in the management of WLB and BOM among teachers. The researchers are optimistic that the extension of REOHC to other related social and psychological‐based self‐defeating belief by social workers, psychologists, counselors, and employers of labors can enhance their productivity and emotionality in the home and workplace.
Combined blue light and daily thermocycles enhance zebrafish growth and development
Authors: de Alba Gonzalo , Carrillo Sherezade , Sánchez‐Vázquez Francisco Javier , López‐Olmeda José Fernando
Published: February 2022

In the wild, the light/temperature environment cyclically oscillates insofar as the temperature rises after dawn and drops after dusk. In the underwater photo‐environment, light is filtered through the water column so that blue photons reach greater depths. This paper investigates the combined effects of both factors with two temperature regimes (constant temperature = 26°C, CTE vs. daily thermocycle = 28°C day:24°C night, TC) and three light wavelengths (white‐W, blue‐B, red‐R) on Danio rerio embryos and larvae from fertilization to 30 days post‐fertilization (dpf). It studied hatching rate, larval survival, growth, and food intake (gut content). It analyzed the expression of the genes involved in stress (crh), somatic growth (gh, ifg1a, igf2a), and food intake control (npy, agrp, ghrelin, orexin, mch1, mch2, grp, cck8) at 10 and 30 dpf. The results revealed that the lowest hatching rate was in R regardless of the temperature regime. The highest growth rate was for the larvae reared with B + TC, which was consistent with the highest expression values of the growth factors. The highest feeding and expression levels of the genes involved in food intake were for the larvae in B (regardless of the temperature regime) and W + TC. Conversely, the R + CTE combination obtained the worst growth and feeding results. These findings indicate that the best larval performance can be achieved with combinations of blue wavelengths and cyclic temperature regimes that come closer to those in the natural environment. These results should be considered when optimizing rearing protocols to improve the growth and welfare of the fish larvae.
COVID‐19 crisis and risk spillovers to developing economies: Evidence from Africa
Authors: Akhtaruzzaman Md , Benkraiem Ramzi , Boubaker Sabri , Zopounidis Constantin
Published: February 2022

This study provides new evidence on how risk spillovers occur from the United States to developing economies in Africa during the COVID‐19 pandemic. The results show that downside risk exposures of African markets, financial firms and banks particularly increased during Phase I (30 January to 30 April 2020). The nature and magnitude of downside risk exposures of African financial markets were similar to those of the United States. Our results also reveal that the United States is a net transmitter of risk spillovers while Nigeria, South Africa, Egypt and Morocco are net recipients. Our conclusions offer guidance to risk managers, policymakers and investors.
Synthesis and identification of lithocholic acid 3-sulfate as RORγt ligand to inhibit Th17 cell differentiation
Authors: Xiao Riping , Lei Kawai , Kuok Hioha , Deng Wende , Zhuang Yuxin , Tang Yanqing , Guo Zhengyang , Qin Hongyan , Bai Li-Ping , Li Ting
Published: February 2022

Primary bile acids (BAs), products of cholesterol metabolism and clearance, are synthesized in the liver and released into the intestine to facilitate the digestion and absorption of lipids. BAs are further converted by gut commensal bacteria into secondary colonic BAs and the metabolism disorder is closely linked to cholestatic liver diseases via regulating immune response. However, the effect and underlying mechanism of these host-microorganism biliary metabolites on T lymphocyte remain unclear. In the current study, we synthesized a sulfated product of lithocholic acid (LCA), lithocholic acid 3-sulfate (LCA-3-S), and investigated the binding affinity of the BAs metabolites on RORγt, the transcription factor of IL-17A. Our results demonstrated that the sulfate of LCA, LCA-3-S, exhibited better effect than its oxidated metabolite, 3-oxo-LCA, binding to RORγt. The results further demonstrated that LCA-3-S selectively suppressed Th17 cell differentiation without influence on Th1, Th2, and Treg cells. Collectively, we synthesized the sulfated biliary metabolite LCA-3-S and demonstrated that LCA-3-S selectively inhibited Th17 cell differentiation by targeting RORγt, indicating that metabolite disorder of BAs resulting in the decrease of LCA-3-S probably contributes to the pathogenesis of cholestatic liver diseases.
Manipulations of sleep‐like slow‐wave activity by noninvasive brain stimulation
Authors: DiNuzzo Mauro , Mangia Silvia , Giove Federico
Published: February 2022

Sleep is a universal and evolutionarily conserved behavior among many animal species, yet we do not have a fundamental understanding of why animals need to sleep. What we do know, however, is that sleep is critical for behavioral performance during the waking period and for long‐term brain health. Here we provide an overview of some putative mechanisms that mediate the restorative effects of sleep, namely metabolic biosynthesis, fluid perfusion, and synaptic homeostasis. We then review recent experimental findings that advance the possibility of inducing sleep‐like slow‐wave activity (SWA) during wakefulness or enhance SWA during sleep in a top‐down manner using noninvasive brain stimulation. SWA induction and SWA enhancement are believed to recapitulate the beneficial effects of sleep independent of the actual state of the subjects. If confirmed, these observations will change the way in which we investigate the neural correlates of sleep, thus paving the way for comprehending and actively controlling its restorative function.
Spatial Control over Stable Light‐Emission from AC‐Driven CMOS‐Compatible Quantum Mechanical Tunnel Junctions
Authors: Wang Fangwei , Hoang Thanh Xuan , Chu Hong‐Son , Nijhuis Christian A.
Published: February 2022

The potential application of quantum mechanical tunnel junctions as subdiffraction light or surface plasmon sources has been explored for decades, but it has been challenging to create devices with subwavelength spatial control over the light or plasmon excitation. This paper describes spatial control over the electrical excitation of surface‐plasmon polaritons (SPPs) and photons in large‐area junctions of the form of Al–AlOX–Cu complementary metal‐oxide‐semiconductor (CMOS)‐compatible tunnel junctions. Nanoscale spatial control (smallest feature sizes of 150 nm) is achieved by locally fine‐tuning the thickness of the AlOX tunneling barrier resulting in large local tunneling currents and associated SPP excitation rates. Mostly, plasmonic tunnel junctions are studied under DC operation with a relatively large bias (and associated currents) to observe light emission at optical frequencies. Large voltages risk device failure and reduce device lifetimes. Here it is demonstrated that the operational lifetime of AC‐driven plasmonic tunnel junctions is improved by a factor of three. Under DC conditions, slow processes that lead to device failure (e.g., undesirable electromigration leading to shorts) readily occur, thus limiting the device decay time to 9.2 h; but under AC operation, such processes are slow with respect to the voltage changes prolonging the decay time beyond 18.0 h.
Status 1B designation does not adequately prioritize children with acute‐on‐chronic liver failure for liver transplantation
Authors: Mataya Leslie , Bittermann Therese , Quarshie William O. , Griffis Heather , Srinivasan Vijay , Rand Elizabeth B. , Alcamo Alicia M.
Published: February 2022

Acute‐on‐chronic liver failure (ACLF) is an acute decompensation of chronic liver disease leading to multiorgan failure and mortality. The objective of this study was to evaluate characteristics and outcomes of children with ACLF who are at the highest priority for liver transplantation (LT) on the United Network for Organ Sharing (UNOS) database—listed as status 1B. The characteristics and outcomes of 478 children with ACLF listed as status 1B on the UNOS LT waiting list from 2007–2019 were compared with children with similar or higher priority listing for transplant: 929 with acute liver failure (ALF) listed as status 1A and 808 with metabolic diseases and malignancies listed as status 1B (termed “non‐ACLF”). Children with ACLF had comparable rates of cumulative organ failures compared with ALF (45% vs. 44%; p > 0.99) listings, but higher than non‐ACLF (45% vs. 1%; p < 0.001). ACLF had the lowest LT rate (79%, 84%, 95%; p < 0.001), highest pre‐LT mortality (20%, 11%, 1%; p < 0.001), and longest waitlist time (57, 3, 56 days; p < 0.001), and none recovered without LT (0%, 4%, 1%; p < 0.001). In survival analyses, ACLF was associated with an increased adjusted hazard ratio (HR) for post‐LT mortality (HR, 1.50 vs. ALF [95% confidence interval, CI, 1.02–2.19; p = 0.04] and HR, 1.64 vs. non‐ACLF [95% CI, 1.15–2.34; p = 0.01]). ACLF has the least favorable waitlist and post‐LT outcomes of all patients who are status 1A/1B. Increased prioritization on the LT waiting list may offer children with ACLF an opportunity for enhanced outcomes.