bluuebunny/crossref_metadata_2025 huggingface dataset:
Reduction of Nitrous Oxide by Light Alcohols Catalysed by a Low‐Valent Ruthenium Diazadiene Complex
Authors: Bösken Jonas , Rodríguez‐Lugo Rafael E. , Nappen Sven , Trincado Monica , Grützmacher Hansjörg
Published: January 2023

Decomposition of the environmentally harmful gas nitrous oxide (N2O) is usually performed thermally or catalytically. Selective catalytic reduction (SCR) is currently the most promising technology for N2O mitigation, a multicomponent heterogeneous catalytic system that employs reducing agents such as ammonia, hydrogen, hydrocarbons, or a combination thereof. This study reports the first homogenous catalyst that performs the reduction of nitrous oxide employing readily available and cheap light alcohols such as methanol, ethanol or ethylene glycol derivatives. During the reaction, these alcohols are transformed in a dehydrogenative coupling reaction to carboxylate derivatives, while N2O is converted to N2 and H2O, later entering the reaction as substrate. The reaction is catalysed by the low‐valent dinuclear ruthenium complex [Ru2H(μ‐H)(Me2dad)(dbcot)2] that carries a diazabutadiene, Me2dad, and two rigid dienes, dbcot, as ligands. The reduction of nitrous oxide proceeds with low catalyst loadings under relatively mild conditions (65–80 °C, 1.4 bar N2O) achieving turnover numbers of up to 480 and turnover frequencies of up to 56 h−1.
Kinetics of polyvinyl butyral (PVB) synthesis reaction catalyzed by deep eutectic solvent
Authors: Luan Wenwen , Xu Jumei , Zeng Zuoxiang , Xue Weilan , Bai Yu
Published: January 2023

In this work, the kinetics of the polyvinyl butyral (PVB) synthesis reaction catalyzed by the deep eutectic solvents (DESs) at the low‐temperature stage was studied to control the particle size of PVB resin and optimize its synthesis process. The effects of stirring speed, the concentration of polyvinyl alcohol (PVA), catalyst dosage, and temperature on the synthesis reaction of PVB were investigated. The data obtained from kinetic experiments at 283.15–298.15 K were fitted with the shrinking core models, and the results showed that the model controlled by internal diffusion fitted well with the experimental data. The internal diffusion coefficient, DA, of n‐butanal in the product layer was further calculated by the obtained model parameters, and it was applied to predict the synthesis reaction of PVB at different concentrations of n‐butanal. The results indicated that the shrinking core model controlled by internal diffusion is suitable to describe the kinetics of the PVB synthesis reaction. DES played a dual role in catalysis and dispersion in the synthesis of PVB, and it was a green catalyst with good potential for PVB industrial applications.
Association between visceral adiposity index and heart failure: A cross‐sectional study
Authors: Zhang Xinyu , Sun Yijun , Li Ying , Wang Chengwei , Wang Yi , Dong Mei , Xiao Jie , Lin Zongwei , Lu Huixia , Ji Xiaoping
Published: January 2023

Background

Obesity is an important risk factor for heart failure (HF).

Hypothesis

Visceral adiposity index (VAI) is a simple metric for assessing obesity; however, the association between VAI and risk for HF has not been studied.

Methods

A cross‐sectional study involving 28 764 participants ≥18 years of age from the National Health and Nutrition Examination Survey (NHANES), 2009–2018, in the United States was performed. VAI was calculated using body mass index (BMI), waist circumference (WC), triglycerides (TG), and high‐density lipoprotein cholesterol. VAI was analyzed as a continuous and categorical variable to examine its association with HF. Subgroup analysis was also performed.

Results

The highest VAI (fourth quartile [Q4]) was found among males, BMI, systolic and diastolic blood pressure, WC, hypertension, diabetes, liver disease, coronary heart disease, smoking, total cholesterol, and TG. More participants in Q4 took β‐receptor blockers, angiotensin‐converting enzyme inhibitors/angiotensin II receptor blockers/angiotensin receptor‐neprilysin inhibitor, calcium channel blockers, and antidiabetic and antihyperlipidemic medications. Participants with HF exhibited greater VAI. A per‐unit increase in VAI resulted in a 4% increased risk for HF (odds ratio [OR] 1.04 [95% confidence interval (CI) 1.02–1.05]). After multivariable adjustment, compared with the lowest quartile, the OR for Q3 was 1.55 (95% CI 1.24–1.94). Subgroup analysis revealed no significant interactions between VAI and specific subgroups.

Conclusion

VAI was independently associated with the risk for HF. As a noninvasive index of visceral adiposity, VAI could be used for a “one shot” assessment of HF risk and may serve as a novel marker.
Differentiating protective factors for transgender individuals who experience suicidality: The role of optimism as a mediator
Authors: Burish Emily , Wilcox Melanie M. , Pollard Elinita M. , Sims K' Nadja
Published: January 2023

As a result of experiencing oppression‐based stressors and trauma, suicide rates for lesbian, gay, bisexual and transgender (LGBTQ+) individuals are much higher than in the general population, and for trans and gender non‐binary (TGNB) individuals specifically, rates of suicidality are even higher. To best understand how to engage in suicide prevention and intervention efforts for TGNB individuals, it is therefore crucial to understand factors that may mitigate suicidality for TGNB individuals. The purpose of this study was to examine the relationship between protective factors—body acceptance, optimism, social support and pride—and suicidality for TGNB adults. A total of 139 TGNB participants completed an online survey about suicidal behaviours, transgender‐specific risk factors and transgender‐specific protective factors. High rates of suicidality were observed in our sample. Initial results suggested that only optimism was inversely significantly related to suicidality. Given that optimism, which suggests a belief in a better future, has been found in previous studies to buffer the effects of deleterious stressors, optimism was also examined as a mediator between body acceptance (a key feature of gender dysphoria) and suicidality. Results suggested that optimism did mediate the relationship between body acceptance and suicidality. Optimism appears to be an important protective factor against suicidality for TGNB individuals and thus a potentially important target of intervention.
Tailoring Pore Size and Catalytic Activity in Cobalt Iron Layered Double Hydroxides and Spinels by Microemulsion‐Assisted pH‐Controlled Co‐Precipitation
Authors: Rabe Anna , Jaugstetter Maximilian , Hiege Felix , Cosanne Nicolas , Ortega Klaus Friedel , Linnemann Julia , Tschulik Kristina , Behrens Malte
Published: January 2023

Cobalt iron containing layered double hydroxides (LDHs) and spinels are promising catalysts for the electrochemical oxygen evolution reaction (OER). Towards development of better performing catalysts, the precise tuning of mesostructural features such as pore size is desirable, but often hard to achieve. Herein, a computer‐controlled microemulsion‐assisted co‐precipitation (MACP) method at constant pH is established and compared to conventional co‐precipitation. With MACP, the particle growth is limited and through variation of the constant pH during synthesis the pore size of the as‐prepared catalysts is controlled, generating materials for the systematic investigation of confinement effects during OER. At a threshold pore size, overpotential increased significantly. Electrochemical impedance spectroscopy (EIS) indicated a change in OER mechanism, involving the oxygen release step. It is assumed that in smaller pores the critical radius for gas bubble formation is not met and therefore a smaller charge‐transfer resistance is observed for medium frequencies.
Critical Techniques for Overcoming the Diffusion Limitations in Heterogeneously Catalytic Depolymerization of Lignin
Authors: Li Lixia , Cui Manman , Wang Xiaobing , Long Jinxing
Published: January 2023

Heterogeneously catalyzed depolymerization of lignin to value‐added chemicals is increasingly attractive but highly challengeable. Particularly, the diffusion limitation of lignin macromolecule to the solid catalyst surface is a big barrier, which significantly decreases the yield of monomer while increasing char formation. Therefore, for the potential industrial utilization of lignin, new knowledge focused on the size of lignin particles is of great importance to offer guidance for promoting lignin depolymerization and suppressing condensation in the heterogeneously catalytic systems. In this Review, the size of lignin particles and macromolecules are summarized. Previous approaches for improving the mass diffusion including enhancing the solubility of lignin and exploitation of hierarchical and “solubilized” materials are also discussed. Based on these, a constructive perspective is proposed. Thus, this work provides a new insight on the rational design of heterogeneous catalytic techniques for efficient utilization of the aromatic polymer of lignin.
A frequency‐doubling modulation method for LLC with optimizing thermal balance of power switches
Authors: Tang Yu , Liu Xiang , Shi Zhe , Ge Leijiao , Jiang Lin
Published: January 2023

In order to further improve the energy efficiency of power electronic systems, DC‐DC converters can increase the power density by increasing the operating frequency to reduce the size and cost. To this end, some scholars have proposed a single‐switch frequency‐doubling (SS‐FD) modulation method, which can make the working frequency of the resonant tank of the converter twice the switching frequency. However, when the full‐bridge LLC converter operates under the SS‐FD modulation, the conduction time of each switch of the same bridge arm is different, which leads to uneven heating of the switches and reduces the overall life of the device. In order to optimize this problem, this paper proposes a dual‐switches time‐sharing frequency‐doubling (DSTS‐FD) modulation. This modulation method ensures that the resonant tank works under the premise of frequency doubling, so that the heating of each switch is more balanced, thereby increasing the overall service life of the equipment. Theoretical analysis is carried out through simulation. Finally, an experimental device of 288 V and 1000 W is built. The proposed modulation method is compared with the traditional modulation method in a stable state, and the experiment verifies the superiority of the proposed modulation method.
Pramipexole inhibits formalin‐induce acute and long‐lasting mechanical hypersensitivity via NF‐kB pathway in rats
Authors: Santamaria‐Anzures Jazmín , Pérez‐Ramos Julia , Mendoza‐Pérez Felipe , Godínez‐Chaparro Beatriz
Published: January 2023

Pain is one of the most frequent causes for patients to seek medical care. It interferes with daily functioning and affects the quality of life of the patient. There is a clear need to investigate nonopioid or non‐nonsteroidal anti‐inflammatory drug alternatives for the treatment of pain. In this study, we determined the effect of acute pre‐ and posttreatment with pramipexole (PPX), a dopamine D2/D3 selective agonist, on formalin 1%‐induced acute and long‐lasting nociceptive behavior sensitivity in rats. Moreover, we sought to investigate whether the antiallodynic and antihyperalgesic effect induced by PPX was mediated through the nuclear factor‐κB (NF‐kB) signaling pathway. Moreover, acute systemic pretreatment with PPX (1 and 3 mg/kg, ip) suppressed the formalin‐induced nociceptive behavior during both phases of the formalin test and the development of formalin‐induced secondary mechanical allodynia and hyperalgesia in both paws. Acute systemic posttreatment with PPX (3 mg/kg, ip) reverted the formalin‐induced long‐lasting secondary mechanical allodynia and hyperalgesia. Furthermore, PPX inhibits the protein expression of NF‐κB–p65 and the levels of tumor necrosis factor‐α and interleukin‐1β in the spinal cord of animals with secondary mechanical allodynia and hyperalgesia induced by formalin. These data suggest that PPX has a potential role in producing anti‐inflammatory activity. Moreover, the antiallodynic and antihyperalgesic effects induced by PPX can be mediated through the NF‐kB signaling pathway.
Alcohol‐Assisted Synthesis of Sheet‐Like ZSM‐5 Zeolites with Controllable Aspect Ratios
Authors: Zhu Peng , Wang Jinshan , Xia Fei , Zhang Wei , Liu Haiou , Zhang Xiongfu
Published: January 2023

Sheet‐like ZSM‐5 has been regarded as a promising material for catalytic applications due to its diffusion superiority. However, it still remains a challenge to obtain a desirable sheet‐like morphology because of the complex synthesis process of zeolites. Here, a facile strategy for synthesizing sheet‐like ZSM‐5 is developed by only adding ethanol as zeolite growth modifier in the synthesis gel. It is thought that ethanol might be preferentially absorbed on the {010} surface of zeolite crystals, interact with the exposed silicon hydroxyl groups on the crystal {010} facet, and suppress the growth of b axis, resulting in the sheet‐like shape. Through finely tunning synthesis parameters, sheet‐like ZSM‐5 crystals with thin b‐axis thickness of 90 nm and different aspect ratios could be obtained. Owing to its shorter diffusion path and optimized acidity, sheet‐like ZSM‐5 exhibits better catalytic performance than conventional ZSM‐5 in the alkylation of benzene with ethanol.
The Application of Mealworm (Tenebrio molitor) Oil in Cosmetic Formulations
Authors: Verheyen Geert R. , Meersman Filip , Noyens Isabelle , Goossens Sarah , Van Miert Sabine
Published: January 2023

The depletion of natural resources, the increasing use of valuable land surface for human activities, and the generation of waste are detrimental to the planet. Sustainable alternatives to guarantee a sufficient supply of food, feed, and biomaterials are needed. Insects may hold an interesting position in a circular economy to tackle contemporary societal challenges. Using insects for food, feed, biomaterial production, and to valorize side‐streams, have gained increased interest. Mealworms are amenable to large‐scale farming. Herein, the potential of mealworm oil for implementation in a cosmetic hand cream is evaluated. It is shown that mealworms are rich in oil (≈30% of the dry weight), and the oil can be extracted using hexane or ethyl acetate as a solvent. The euthanization step of mealworms has profound effect on the free fatty acid content. The fatty acid profile indicates a large proportion of unsaturated fatty acids, which is promising for use in cosmetic applications. In a proof of concept, the mealworm oil is implemented in a hand cream and compared to hand cream containing macadamia nut oil. No differences in odor and aspect/stability are observed, but mealworm creams are slightly less white color. Mealworm oil is suitable for cosmetics applications.

Practical applications: Several insect species can be sustainably reared on low‐value organic side‐streams, requiring only small amounts of land‐surface, less water, and producing less greenhouse gases. In addition, they have short life cycles and can be reared continuously and locally. This implies that insects are an interesting source of biological materials including proteins and oils. Insect oils, including oil of mealworms, have interesting fatty acid profiles that make them amenable to replace oils of vegetable origin for applications within cosmetics. The results indicate that mealworm oil can be a novel, sustainable ingredient for use in the cosmetics industry.
Synthesis of Bifunctional Lipoxin‐Derived Enzyme‐Triggered CO‐Releasing Molecules (LipET‐CORMs)
Authors: Hemmersbach Lars , Adam Ruth , Plevnali Christina , Zhang Xinmiao , Yard Benito , Schmalz Hans‐Günther
Published: January 2023

In an attempt to develop new anti‐inflammatory agents which act by co‐release of carbon monoxide (CO) and a specialized pro‐resolving mediator, we designed conjugates of a lipoxin A4 analogue and an acyloxycyclohexadiene‐Fe(CO)3 complex as an esterase‐triggered CO‐releasing molecule (ET‐CORM). After adjustment of the protecting group strategy, two of such compounds were successfully prepared by total synthesis (12 steps; 4–5 % overall yield) starting from deoxy‐d‐ribose and exploiting a Wittig olefination and an intermolecular Heck reaction as key C−C bond‐forming steps. A crucial late reduction of an aryl‐ketone moiety in the presence of a highly sensitive dienol ester functionality was achieved with BH3‐SMe2 in the presence of catalytic amounts of NaBH4. Both target compounds were dose‐dependently toxic towards cultured human umbilical vein endothelial cells (HUVEC), with LipET‐CORM 1‐A being slightly more toxic. While induction of heme oxygenase 1 (HO‐1) in HUVEC was observed for both compounds, they did not inhibit TNF‐α‐mediated VCAM‐1 expression in these cells. In M2 polarized macrophages HO‐1 expression was more pronounced as compared to M1 polarized macrophages. In both types of macrophages HO‐1 expression was downregulated by lipopolysaccharide, but only in M2 macrophages HO‐1 expression was rescued by LipET‐CORM. 15‐Lipoxygenase (15‐LO) was only expressed in M2 macrophages and was not influenced by LipET‐CORM. Collectively our data demonstrate that LipET‐CORMs induce HO‐1 expression in endothelial cells and M2 polarized macrophages. The role of the intra‐cellular released lipoxin A4 in resolution of inflammation, however, remains to be assessed.
Failure mechanism and divisional differentiated control of surrounding rock in mining roadway under remaining coal pillar in close‐distance coal seam
Authors: Chen Dong‐dong , Ma Xiang , Wu Yi‐yi , Xie Sheng‐rong , Li Hui , Jiang Zai‐sheng , Wang En , Guo Fang‐fang , Guo Wen‐ke , Ye Qiu‐cheng
Published: January 2023

Regarding the issue of intense mining pressure appearing in the underlying gateway below the remaining coal pillar in the close‐distance coal seam (the remaining coal pillar is perpendicular to the underlying section coal pillar), 401 working face is used as the engineering background. Field measurements, laboratory experiments, numerical simulations, and engineering verification techniques are used to study the abutment pressure's evolution properties and the plastic zone's propagation laws before and after the underlying coal seam roadway experienced the mining impact. The conclusions are as follows: ① The maximum plastic area on the two sides and the roof of the roadway underlying the gob are up to 2 and 1.5 m, whereas the maximum plastic area on the two sides and the roof of the roadway underlying the remaining coal pillar are up to 5 and 4.5 m, respectively. Moreover, the plastic area extends along the two sides, and the section coal pillar is completely broken when the working face is mined below the remaining coal pillar. ② The stress increase coefficient K in the overlap area of the remaining coal pillar and the underlying section coal pillar reaches 3.4 when the mining face penetrates the underlying remaining coal pillar and the advance abutment pressure is overlaid with the concentrated stress of the coal pillar. ③ When the underlying working face is mined to 4, −2, −8, and −14 m away from the remaining coal pillar, the damage range of the roadway 5–10 m ahead increases in turn. At the same time, the maximum plastic area of the roof passes through the plastic area of the upper coal seam floor. Therefore, the underlying and transition areas on both sides of the remaining coal pillar are divided into Area I (15 m) → Area II (the most complicated area to control under the remaining coal pillar, 20 m) → Area III (25 m) according to the width. Furthermore, the divisional differentiated combined control technology of channel steel truss anchor cable with joint double‐way locking control function of roof and coal pillar in Areas I and III, while channel steel truss anchor cable with joint double‐way locking control function of roof and side + high resistance integral door‐type support is proposed in Area II. Field engineering practice shows that the deformation of the roadway surrounding rock can be controlled within 210 mm after adopting the above divisional combined control technology. Finally, the mining operation can safely and efficiently pass through the remaining coal pillar. The research results have important reference values for surrounding rock control of mining roadways in the overlapping area of similar “+”‐type cross‐working face.
Revisiting western United States hydroclimate during the last deglaciation
Authors: Fu Minmin
Published: January 2023

During the last ice age, the western United States was covered by large
lakes, sustained partly by higher levels of precipitation. Increased
rainfall was driven by the atmospheric circulation associated with the
presence of large North American ice sheets, yet Pleistocene lakes
generally reached their highstands not at glacial maximum but during
deglaciation. Prior modeling studies, however, showed nearly monotonic
drying since the last glacial maximum. Here I show that iTraCE, a new
transient climate simulation of the last deglaciation, reproduces a
robust peak in winter rainfall over the Great Basin near 16 ka. The
simulated peak is driven by a transient strengthening and southward
shift of the midlatitude jet. While meltwater forcing is an important
driver of changes to the North Pacific Jet, changing orbital conditions
and rising atmospheric CO also shift the jet south and
contribute to wetter conditions over the western US during deglaciation.
Updating the Chronic Freshwater Ecotoxicity Database and Biotic Ligand Model for Nickel for Regulatory Applications in Europe
Authors: Peters Adam , Nys Charlotte , Leverett Dean , Wilson Iain , Van Sprang Patrick , Merrington Graham , Middleton Elizabeth , Garman Emily , Schlekat Christian
Published: January 2023

Bioavailability has been taken into account in the regulation of nickel in freshwater ecosystems in Europe for over a decade; during that time a significant amount of new information has become available covering both the sensitivity of aquatic organisms to nickel toxicity and bioavailability normalization. The ecotoxicity database for chronic nickel toxicity to freshwater organisms has been updated and now includes 358 individual data points covering a total of 53 different species, all of which are suitable for bioavailability normalization to different water chemistry conditions. The bioavailability normalization procedure has also been updated to include updates to the bioavailability models that enable more sensitive water chemistry conditions to be covered by the model predictions. The updated database and bioavailability normalization procedure are applicable to more than 95% of regulated European surface water conditions and have been used to calculate site-specific criteria for a variety of different water chemistry scenarios, to provide an indication of how the sensitivity to nickel varies between different water types. The hazardous concentration for 5% of a species (HC5) values for this diverse selection of water types range from 1.6 to 36 µg L–1, clearly demonstrating the importance of accounting for nickel bioavailability in freshwaters. This updated database and bioavailability normalization procedure provide a robust basis for the derivation of regulatory thresholds for chronic nickel toxicity in freshwaters such as predicted no-effect concentrations and Environmental Quality Standards and are protective of the results of several mesocosm studies. Environ Toxicol Chem 2023;42:566–580. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
Assessment of high‐order IMEX methods for incompressible flow
Authors: Guesmi Montadhar , Grotteschi Martina , Stiller Jörg
Published: January 2023

This paper investigates the competitiveness of semi‐implicit Runge‐Kutta (RK) and spectral deferred correction (SDC) time‐integration methods up to order six for incompressible Navier‐Stokes problems in conjunction with a high‐order discontinuous Galerkin method for space discretization. It is proposed to harness the implicit and explicit RK parts as a partitioned scheme, which provides a natural basis for the underlying projection scheme and yields a straight‐forward approach for accommodating nonlinear viscosity. Numerical experiments on laminar flow, variable viscosity and transition to turbulence are carried out to assess accuracy, convergence and computational efficiency. Although the methods of order 3 or higher are susceptible to order reduction due to time‐dependent boundary conditions, two third‐order RK methods are identified that perform well in all test cases and clearly surpass all second‐order schemes including the popular extrapolated backward difference method. The considered SDC methods are more accurate than the RK methods, but become competitive only for relative errors smaller than ca .
The geopolitical risk premium in the commodity futures market
Authors: Cheng Daxuan , Liao Yin , Pan Zheyao
Published: January 2023

In this study, we investigate the geopolitical risk premium in the commodity futures market. By estimating the exposure of cross‐sectional commodity futures excess returns on a historical geopolitical risk index, we find that commodities with low‐risk betas generate 9.05% higher annual risk‐adjusted returns than those with high‐risk betas. The results indicate that low‐geopolitical‐risk‐related commodity futures contracts require extra compensation by risk‐averse investors due to hedging demand. We also explore the time‐varying characteristics of the geopolitical risk premium: It appears more pronounced during high‐geopolitical‐risk periods and before the year 2000. Finally, we exploit the subcategories of geopolitical risk and find that geopolitical threats better explain the variation of the geopolitical risk premium than do geopolitical acts, making it a main source of the geopolitical risk premium.
Analysis of ecological health status of the Muni Lagoon: Evidence from heavy metal content in its water and fish samples
Authors: Okyere Emmanuel Yeboah , Adu‐Boahen Kofi , Boateng Isaac , Dadson Ishmael Yaw , Boanu Nelson Yeboah , Kyeremeh Sender
Published: January 2023

The study examined the ecological health status of the Muni lagoon amidst increasing development in and around its catchment using a concentration of heavy metals in its water and fish samples as a proxy. Flame atomic absorption spectrophotometer (FAAS) laboratory analysis was employed to determine heavy metals (cadmium [Cd], lead [Pb], iron [Fe], manganese [Mn] and zinc) present in water and fish samples within the Muni Lagoon. The study revealed that the Muni Lagoon and feeder rivers were polluted with heavy metals (Fe = 0.453, Cd = 0.201, Mn = 0.105 and Pb = 0.024) comparing their concentrations with the US Environmental Protection Agency (USEPA) and Water Resources Commission (WRC) limit. Fish within the lagoon were found to pose no harm to consumers as traces of heavy metal concentrations were below the Food and Agriculture Organisation of the United Nations/World Health Organisation maximum permissible limit. The study further revealed that the application of agricultural inputs such as fertilisers, pesticides and domestic waste as well as unregulated gutter channels were the major source of heavy metals. A paired sample t‐test showed a statistically significant difference between the wet and dry season's concentrations of cadmium and lead. For cadmium, the t‐test found t(5) = −7.265; p = .001 between the wet season's concentration and the dry season's concentration and for lead, the t‐test found t(5) = 5.061, p = .004 between the wet and dry season concentrations in the lagoon. It is therefore recommended that the Forestry Commission, Municipal Assembly and the local leaders should collaborate in regulating activities occurring in and around the catchment of the lagoon.
Deficient deposition of new myelin impairs adult optic nerve function in a murine model of diabetes
Authors: Wu Haoqian , Chen Xianjun , Yu Bin , Zhang Jieqiong , Gu Xingmei , Liu Wei , Mei Feng , Ye Jian , Xiao Lan
Published: January 2023

Visual impairment in diabetes is a growing public health concern. Apart from the well‐defined diabetic retinopathy, disturbed optic nerve function, which is dependent on the myelin sheath, has recently been recognized as an early feature of visual impairment in diabetes. However, the underlying cellular mechanisms remain unclear. Using a streptozotocin‐induced diabetic mouse model, we observed a myelin deficiency along with a disturbed composition of oligodendroglial lineage cells in diabetic optic nerve. We found that new myelin deposition, a continuous process that lasts throughout adulthood, was diminished during pathogenesis. Genetically dampening newly generated myelin by conditionally deleting olig2 in oligodendrocyte precursor cells within this short time window extensively delayed the signal transmission of the adult optic nerve. In addition, clemastine, an antimuscarinic compound that enhances myelination, significantly restored oligodendroglia, and promoted the functional recovery of the optic nerve in diabetic mice. Together, our results point to the role of new myelin deposition in optic neuropathy under diabetic insult and provide a promising therapeutic target for restoring visual function.
Disentangling poststroke cognitive deficits and their neuroanatomical correlates through combined multivariable and multioutcome lesion‐symptom mapping
Authors: Weaver Nick A. , Mamdani Muhammad Hasnain , Lim Jae‐Sung , Biesbroek Johannes Matthijs , Biessels Geert Jan , Huenges Wajer Irene M. C. , Kang Yeonwook , Kim Beom Joon , Lee Byung‐Chul , Lee Keon‐Joo , Yu Kyung‐Ho , Bae Hee‐Joon , Bzdok Danilo , Kuijf Hugo J.
Published: January 2023

Studies in patients with brain lesions play a fundamental role in unraveling the brain's functional anatomy. Lesion‐symptom mapping (LSM) techniques can relate lesion location to cognitive performance. However, a limitation of current LSM approaches is that they can only evaluate one cognitive outcome at a time, without considering interdependencies between different cognitive tests. To overcome this challenge, we implemented canonical correlation analysis (CCA) as combined multivariable and multioutcome LSM approach. We performed a proof‐of‐concept study on 1075 patients with acute ischemic stroke to explore whether addition of CCA to a multivariable single‐outcome LSM approach (support vector regression) could identify infarct locations associated with deficits in three well‐defined verbal memory functions (encoding, consolidation, retrieval) based on four verbal memory subscores derived from the Seoul Verbal Learning Test (immediate recall, delayed recall, recognition, learning ability). We evaluated whether CCA could extract cognitive score patterns that matched prior knowledge of these verbal memory functions, and if these patterns could be linked to more specific infarct locations than through single‐outcome LSM alone. Two of the canonical modes identified with CCA showed distinct cognitive patterns that matched prior knowledge on encoding and consolidation. In addition, CCA revealed that each canonical mode was linked to a distinct infarct pattern, while with multivariable single‐outcome LSM individual verbal memory subscores were associated with largely overlapping patterns. In conclusion, our findings demonstrate that CCA can complement single‐outcome LSM techniques to help disentangle cognitive functions and their neuroanatomical correlates.
Alternative Synthesis of 5‐(1H‐Pyrazol‐4‐yl)‐2‐{6‐[(2,2,6,6‐tetramethylpiperidin‐4‐yl)oxy]pyridazin‐3‐yl}phenol
Authors: Zhou Jianguang , Gu Xingxian , Yao Shuping , Ye Jiong , Fu Peng , Liu Siqian , Dedic Darija , Gallou Fabrice
Published: January 2023

A scalable and environmentally benign route to the free base of branaplam, a small molecule splicing modulator, was identified and developed. This alternative approach circumvented the inherent risk of dioxin formation associated with ortho‐halo phenol derivatives present in the previous route. A Friedel–Crafts approach provided a reliable access to the key intermediate, subsequently followed by a Suzuki–Miyaura cross‐coupling. Multiple process aspects of the synthetic approach were evaluated, and a robust process for its large‐scale synthesis was developed and successfully demonstrated.
Impact of land cover changes on Long‐Term Regional‐Scale groundwater recharge simulation in cold and humid climates
Authors: Dubois Emmanuel , Larocque Marie , Brunner Philip
Published: January 2023

In cold and humid climates, warming temperatures will result in longer growing seasons, leading to land cover changes that could have long‐term impacts on groundwater recharge (GWR), in addition to the direct impacts of climate change. The objective of this study was therefore to investigate whether land cover (LC) changes need to be considered when simulating long‐term regional‐scale potential GWR in cold and humid climates by (1) quantifying how LC changes impact simulated GWR and (2) quantifying the combined impacts of LC and climate changes on the future GWR changes. Using the region of southern Quebec (Canada) as a case study and a water budget model, this work proposes an innovative coupling of land cover change scenarios and specific future climate conditions to simulate spatially distributed transient GWR over the 1951–2100 period. The results showed that including LC changes in long‐term GWR simulations produced statistically significant increases in GWR compared to using a constant LC through time (average of +13 mm). Massive afforestation taking place on agricultural lands simulated for one of the scenario chains (RCP4.5) increased GWR by reducing runoff during the snow‐dominated period (average − 17 mm). The results also showed that GWR was more sensitive to climate change for scenarios that included intense land cover changes. Additionally, the spatial distribution of the LC changes influenced their simulated impacts on GWR. Considering that the methodology was computationally feasible and entirely transferrable to the new CMIP6 ensemble, LC changes should be considered systematically in long‐term groundwater resources simulations.
CTLA‐4 inhibition facilitates follicular T and B cell interaction and the production of tumor‐specific antibodies
Authors: Jo Areum , Jeong Dasom , Eum Hye Hyeon , Kim Nayoung , Na Minsu , Kang Huiram , Lee Hae‐Ock
Published: January 2023

Immune checkpoint inhibitors (ICIs) induce activation and expansion of cytotoxic T cells. To depict a comprehensive immune cell landscape reshaped by the CTLA‐4 checkpoint inhibitor, we performed single‐cell RNA sequencing in a mouse syngeneic tumor transplant model. After CTLA‐4 inhibition, tumor regression was accompanied by massive immune cell expansion, especially in T and B cells. We found that B cells in tumor transplant represented follicular, germinal center and plasma B cells, some of which shared identical B cell receptor clonotypes and possessed tumor reactivity. Furthermore, the posttreatment tumor contained a tertiary lymphoid‐like structure with intermingled T and B cells. These data suggest germinal center formation within the tumor mass and in situ differentiation of tumor‐specific plasma cells. Taken together, our data provide a panoramic view of the immune microenvironment after CTLA‐4 inhibition and suggest a role for tumor‐specific B cells in antitumor immunity.
Tumorigenic activation around HPV integrated sites in head and neck squamous cell carcinoma
Authors: Mima Masato , Okabe Atsushi , Hoshii Takayuki , Nakagawa Takuya , Kurokawa Tomoya , Kondo Satoru , Mizokami Harue , Fukuyo Masaki , Fujiki Ryoji , Rahmutulla Bahityar , Yoshizaki Tomokazu , Hanazawa Toyoyuki , Misawa Kiyoshi , Kaneda Atsushi
Published: January 2023

Human papillomavirus (HPV) is causally involved in the development of head and neck squamous cell carcinoma (HNSCC). The integration of HPV drives tumorigenesis through expression of oncogenic viral genes as well as genomic alterations in surrounding regions. To elucidate involvement of epigenetic dysregulation in tumorigenesis, we here performed integrated analyses of the epigenome, transcriptome and interactome using ChIP‐seq, RNA‐seq and Hi‐C and 4C‐seq for HPV(+) HNSCCs. We analyzed clinical HNSCC using The Cancer Genome Atlas data and found that genes neighboring HPV integration sites were significantly upregulated and were correlated with oncogenic phenotypes in HPV(+) HNSCCs. While we found four HPV integration sites in HPV(+) HNSCC cell line UPCI‐SCC‐090 through target enrichment sequencing, 4C‐seq revealed 0.5 to 40 Mb of HPV‐interacting regions (HPVIRs) where host genomic regions interacted with integrated HPV genomes. While 9% of the HPVIRs were amplified and activated epigenetically forming super‐enhancers, the remaining non‐amplified regions were found to show a significant increase in H3K27ac levels and an upregulation of genes associated with GO terms, for example, Signaling by WNT and Cell Cycle. Among those genes, ITPR3 was significantly upregulated, involving UPCI‐SCC‐090‐specific super‐enhancer formation around the ITPR3 promoter and in the 80‐kb‐downstream region. The knockdown of ITPR3 by siRNA or CRISPR deletions of the distant enhancer region led to a significant suppression of cell proliferation. The epigenetic activation of HPVIRs was also confirmed in other cell lines, UM‐SCC‐47 and UM‐SCC‐104. These data indicate that epigenetic activation in HPVIRs contributes, at least partially, to genesis of HPV(+) HNSCC.
Mobile and internet usage, institutions and the trade balance: Evidence from African countries
Authors: Nguyen Canh Phuc , Doytch Nadia , Schinckus Christophe , Su Thanh Dinh
Published: January 2023

This study examines the influences of institutions, the Internet and mobile usage on the trade balance of African countries between 2003 and 2017. Our empirical results have been estimated with a panel‐corrected standard error method (PSCE) and they have been confirmed by several alternative techniques. First, the increase of internet usage and mobile usage has a significant negative effect on total and inter‐continental trade balances while these factors improve the intra‐African trade balances. Second, better institutions appear to have a negative impact on the total‐, inter‐, and intra‐African trade balances – in other words, better institutions appear to stimulate imports rather than exports. This observation explains the decreasing trends in the current account balances of African countries. Third, the combined effect of the three factors (institutions, internet, and mobile use together) has a significant positive impact on all trade balances: total‐, inter‐, and intra‐continental. Our study shows that an improvement in institutional quality acts as a mitigating factor for any negative impact internet\mobile development might cause on the trade balances of African countries. Further, our analysis examines the influence of institutions, internet usage, and mobile usage on the two parts of the trade: exports and imports. We observe that internet and mobile can influence negatively and differently impact the two wings of the balance trade. However, all improvements in institutions and their associations with internet usage and mobile usage have a significant positive impact on the trade balance especially on exporting activities of African countries.
Ameliorative effect of ellagic acid and Vitamin C against malathion‐induced toxicity in testis of adult Wistar rats
Authors: Gupta Rahul , Gupta Tinku , Kaushik Dhirender
Published: January 2023

The pesticide malathion (MT), an organophosphate, is highly neurotoxic and causes cholinergic disorders as well as cytotoxicity, genotoxicity, mutagenicity, carcinogenicity and reproductive toxicity. Our purpose was to study the effect of ellagic acid (EA) and Vitamin C on the testis against MT‐induced toxicity in the rats. Thirty‐six adult Wistar rats were employed, separated into six groups and were given treatment for 14 days. The toxicity of MT on the testis was evaluated using a variety of physical parameters, such as mortality rate and body weight, as well as biochemical parameters, such as total protein, total cholesterol, serum glutamic‐oxaloacetic transaminase and serum glutamic‐pyruvic transaminase, and haematological parameters, such as counts of red blood cells, haemoglobin (Hb) and white blood cells, as well as mean corpuscular volume, mean corpuscular Hb, and mean corpuscular Hb concentration. At the end of the experiment, rats were killed and a histological examination of the testis was performed. A sperm count technique and an analysis of sperm motility were used to determine the sperm quality. Biochemical indicators, sperm count, motility, viability and morphology were significantly decreased with MT. When compared with MT and the control group, EA and Vitamin C administration significantly increased sperm motility and count (p < 0.05). After receiving EA and Vitamin C, biochemical indicators and histological characteristics are also intensified. The results of the current investigation show that EA and Vitamin C can both reduce increased levels of biochemical markers and improve pathological alterations in the testis brought on by MT treatment.
Association between physical activity, growth differentiation factor 15 and bodyweight in older adults: A longitudinal mediation analysis
Authors: Raffin Jérémy , Rolland Yves , Parini Angelo , Lucas Alexandre , Guyonnet Sophie , Vellas Bruno , de Souto Barreto Philipe ,   For the MAPT/DSA Group
Published: January 2023

Background

Late‐life aging is often associated with appetite reduction and weight loss. Physical activity (PA) may prevent these processes, but the molecular mechanisms involved remain elusive. The present study investigated the putative mediating aspect of growth differentiation factor 15 (GDF‐15), a stress signalling protein involved in aging, exercise and appetite control, on the association between PA and late‐life‐associated weight loss.

Methods

One thousand eighty‐three healthy adults (63.8% women) aged 70 years and over who participated in the Multidomain Alzheimer Preventive Trial were included. Bodyweight (kg) and PA levels (square root of metabolic equivalent of task‐min/week) were assessed repeatedly from baseline to the 3‐year visit, whereas plasma GDF‐15 (pg/mL) was measured at the 1‐year visit. Multiple linear regressions were performed to test the association between first‐year mean PA level, 1‐year visit GDF‐15 concentration and subsequent bodyweight changes. Mediation analyses were used to investigate whether GDF‐15 mediated the association between first‐year mean PA levels and consecutive bodyweight changes.

Results

Multiple regression analyses demonstrated that higher first‐year mean PA levels significantly predicted lower GDF‐15 and bodyweight at 1 year (B = −2.22; SE = 0.79; P = 0.005). In addition, higher 1‐year visit GDF‐15 levels were associated with faster subsequent bodyweight loss (Time × GDF‐15 interaction B = −0.0004; SE = 0.0001; P = 0.003). Mediation analyses confirmed that GDF‐15 mediated the association between first‐year mean PA levels and subsequent bodyweight changes (mediated effect ab = 0.0018; bootstrap SE = 0.001; P < 0.05) and revealed that mean PA had no direct effect on subsequent bodyweight changes (c′ = 0.006; SE = 0.008; P > 0.05).

Conclusions

This study suggests that GDF‐15 may be one of the molecules mediating the link between PA and late‐life weight loss, but mechanistic studies are necessary to further support the present findings.
Effectiveness of adenosine triphosphate to monitor manual cleaning and disinfection efficacy of flexible endoscopes in Hong Kong
Authors: Chan Ada S F , Chan Henry L Y , Yan Bruno K L , Lai Mooris K C
Published: January 2023

Background and Aim

Adenosine triphosphate (ATP) bioluminescence assay is widely adopted in the West to allow rapid evaluation of endoscopes for bacteriologic/biologic residue, but this practice is rarely adopted in Asia. In this continuous quality improvement program, we evaluated the utility of ATP in bacteriologic surveillance on endoscope reprocessing.

Methods

A total of 456 samples (304 ATP samples and 152 culture samples) of 38 flexible endoscopes were assessed after routine clinical use in a private hospital in Hong Kong. Endoscopes were assessed with an ATP system and bacterial cultures at different time points during the reprocessing.

Results

After pre‐cleaning, the ATP values ranged from 228 to 65 163 relative light units (RLU) through all endoscope types. After manual cleaning, ATP values were decreased to 7–81 RLU (median, 19 RLU) for endoscope surface and 3–671 RLU (median, 12 RLU) for channel rinsate. There was a significant reduction in ATP levels between pre‐cleaning and after manual cleaning. One of the 38 (2.6%) endoscopes (a duodenoscope) had an ATP value of 671 RLU from channel rinsate, which exceeded the benchmark for cleanliness of >200 RLU, and was sent back for re‐cleaning. All endoscopes cultured no bacteria after high‐level disinfection (HLD) by automated endoscope reprocessor (AER) and storage up to 24 h. ATP values were <200 RLU for all endoscopes after HLD and storage.

Conclusions

Adenosine triphosphate bioluminescence assay offers a rapid, practical, and cost‐effective alternative for detection of endoscope microbial residue as well as a routine monitoring tool for endoscope cleanliness in the clinical setting.
Role of neoadjuvant treatment in resectable pancreatic cancer according to vessel invasion and increase of CA19‐9 levels
Authors: Kim Hyeong Seok , Lee Mirang , Han Youngmin , Kang Jae Seung , Kang Yoon Hyung , Sohn Hee Ju , Kwon Wooil , Lee Dong Ho , Jang Jin‐Young
Published: January 2023

Background/Purpose

The efficacy of neoadjuvant treatment (NAT) for resectable pancreatic cancer remains debatable, particularly in patients with portal vein (PV)/superior mesenteric vein (SMV) contact and elevated serum carbohydrate antigen (CA) 19‐9. This study investigated the clinical significance of PV/SMV contact and CA19‐9 levels, and the role of NAT in resectable pancreatic cancer.

Methods

A total of 775 patients who underwent surgery for resectable pancreatic cancer between 2007 and 2018 were included. Propensity score‐matched (PSM) analysis (1:3) was performed based on tumor size, lymph node enlargement, and PV/SMV contact. Subgroup analyses were performed according to PV/SMV contact and CA19‐9 level.

Results

Among the patients, 52 underwent NAT and 723 underwent upfront surgery. After PSM, NAT group showed better survival than upfront surgery group (median 30.0 vs 22.0 months, P = .047). In patients with PV/SMV contact, NAT tended to have better survival (30.0 vs 22.0 months, P = .069). CA19‐9 >150 U/mL was a poor prognostic factor, with NAT showing a significant survival difference compared with upfront surgery (34.0 vs 18.0 months, P = .004).

Conclusions

Neoadjuvant treatment showed better survival than upfront surgery in resectable pancreatic cancer. In patients with PV/SMV contact or CA19‐9 >150 U/mL, NAT showed a survival difference compared to upfront surgery; therefore, NAT could be considered in these patients.