bluuebunny/crossref_metadata_2025 huggingface dataset:
Chemically engineered unzipped multiwalled carbon nanotube and rGO nanohybrid for ultrasensitive picloram detection in rice water and soil samples
Authors: Dkhar Daphika S. , Kumari Rohini , Chandra Pranjal
Published: June 2023

Picloram (4-Amino-3,5,6-trichloro pyridine-2-carboxylic acid) is a chlorinated herbicide that has been discovered to be tenacious and relatively durable in both soil and water. It is known to have adverse and unpleasant effects on humans causing several health complications. Therefore, the determination of picloram is profoundly effective because of its bio-accumulative and persistent nature. Because of this, a sensitive, rapid, and robust detection system is essential to detect traces of this molecule. In this study, we have constructed a novel nanohybrid system comprising of an UZMWCNT and rGO decorated on AuNPs modified glassy carbon electrode (UZMWCNT + rGO/AuNPs/GCE). The synthesized nanomaterials and the developed system were characterized using techniques such as SEM, XRD, SWV, LSV, EIS, and chronoamperometry. The engineered sensor surface showed a broad linear range of 5 × 10–2 nM to 6 × 105 nM , a low limit of detection (LOD) of 2.31 ± 0.02 (RSD < 4.1%) pM and a limit of quantification (LOQ) of 7.63 ± 0.03 pM. The response time was recorded to be 0.2 s, and the efficacy of the proposed sensor system was studied using rice water and soil samples collected from the agricultural field post filtration. The calculated recovery % for picloram in rice water was found to be 88.58%—96.70% (RSD < 3.5%, n = 3) and for soil it was found to be 89.57%—93.24% (RSD < 3.5%, n = 3). In addition, the SWV responses of both the real samples have been performed and a linear plot have been obtained with a correlation coefficient of 0.97 and 0.96 for rice and soil samples, respectively. The interference studies due to the coexisting molecules that may be present in the samples have been found to be negligible. Also, the designed sensor has been evaluated for stability and found to be highly reproducible and stable towards picloram detection.
A closer association between blood urea nitrogen and the probability of diabetic retinopathy in patients with shorter type 2 diabetes duration
Authors: Zhong Jian-Bo , Yao Yu-Feng , Zeng Guo-Qiang , Zhang Yi , Ye Bai-Kang , Dou Xiao-Yan , Cai Li
Published: June 2023

Blood urea nitrogen (BUN) is an indicator of renal function and catabolic status in human body. Diabetic retinopathy (DR) is a major microvascular complication of diabetes mellitus (DM) and a serious threat to the vision of diabetic patients. We included 426 type 2 diabetic patients who visited the endocrinology department of Guangdong Provincial People’s Hospital and received an ophthalmology consultation from December 2017 to November 2018. The outcome was the probability of DR in participants. Multivariable logistics analysis was used to confirm the relationship between BUN and the probability of DR. And interaction tests were conducted to find the effects of DM duration on their association. A total of 167 of 426 patients with type 2 diabetes had DR, with a probability of 39.20%. After adjusting for potential confounders, a positive association between BUN and the probability of DR (OR = 1.12; 95% CI 1.03–1.21; P = 0.0107). And a test for interaction between DM duration and BUN on the probability of DR was significant (P = 0.0295). We suggested that in patients with type 2 diabetes, BUN was positively associated with the probability of DR and the association was influenced by DM duration.
Characteristics of persistent arthritis with refractory Kawasaki disease: a single-center retrospective study
Authors: Hattori Seira , Nozawa Tomo , Nishimura Kenichi , Hara Ryoki , Murase Ayako , Ohara Asami , Ohnishi Ai , Ohya Takashi , Ito Shuichi
Published: June 2023

Arthritis is one complication of Kawasaki disease (KD); however, the clinical features of arthritis in KD have not been well clarified. We retrospectively investigated the characteristics of persistent arthritis beyond the subacute phase of KD. In this cohort, 49 of 243 patients (20%) developed arthritis, with 33 patients (14%) experiencing persistent arthritis. Among these 33 patients, 31 (94%) had complete KD. Thirty (91%) were resistant to first intravenous immunoglobulin, and 15 (45%) required additional infliximab. Five patients (15%) developed coronary artery lesions, and 24 (73%) had oligoarthritis, mainly in large lower-extremity joints. Twenty-four patients (73%) complained of arthralgia. At arthritis onset, 16 patients (48%) presented with fever, including recurrent fever in 10 patients. Serum C-reactive protein concentration in patients with active arthritis significantly increased compared with after acute KD treatment (2.4 vs. 0.7 mg/dL, p < 0.001). Serum matrix metalloproteinase-3, a biomarker of arthritis, was significantly higher in patients with active arthritis than in remission (93.7 vs. 20.3 ng/mL, p < 0.001). Thirty (91%) and 14 (42%) patients, respectively, were treated with non-steroidal anti-inflammatory drugs and prednisolone, and they completely recovered. To summarize, persistent arthritis is a common complication in refractory KD, and adequate diagnosis and treatment are necessary.
Successful targeting in situ of an oncogenic nuclear antigen by hapten induced tumor associated autoantibodies (iTAA)
Authors: Yu Baofa , Zhang Jian , Fu Qiang , Han Yan , Zhang Jie , Gao Feng , Jing Peng , Zhang Peicheng , Zheng Guoqin
Published: June 2023

The abscopal is a hypothesis for treating of non-irradiated tumors after localized radiation therapy. It is associated with the products of tumor-associated gene as autoantibodies (aTAAs) in reaction to the tumor-associated antigens (TAAs), with increasing of anti-MAGEA3 and an relationship between the abscopal effect and immune response. The hapten enhanced local chemotherapy (HELC) was studied to kills tumor and release tumor TAAs, then hapten modify the TAAs to neu-TAAs, to produce tumor autologous antibodies, called induced tumor-associated autoantibodies (iTAAs) that is different from natural TAAs. Since the iTAAs and complement (C) are associated with cancer therapy Immunofluorescence (IF) was applied to evaluate the expression of the iTAAs and C3, C5, C9. Traces resulted in a partial staining of the nucleus in C3’s perinuclear reaction. The iTTAs of Survivin, C-MYC, and IMP1 increased significantly in the tumor cells' intranuclear regions (P = 0.02, P = 0.00, P < 0.0001). Koc, zeta, RalA, and p53 had a similar trend in the perinuclear regions (P < 0.0001, P = 0.004, P < 0.0001, P = 0.003). Therefore, we can propose that tumor antigens inside the cancer cells’ nuclei are targeted by the iTAAs since the iTAAs binding levels are higher after HELC. The iTAA tagging oncogenic nuclear antigens may play a distinctive role in regulating tumor cell growth.
Repurposing of neprilysin inhibitor ‘sacubitrilat’ as an anti-cancer drug by modulating epigenetic and apoptotic regulators
Authors: Kumbhar Navanath , Nimal Snehal , Patil Deeksha , Kaiser V. Florian , Haupt Joachim , Gacche Rajesh N.
Published: June 2023

Modifications in the epigenetic landscape have been considered a hallmark of cancer. Histone deacetylation is one of the crucial epigenetic modulations associated with the aggressive progression of various cancer subtypes. Herein, we have repurposed the neprilysin inhibitor sacubitrilat as a potent anticancer agent using in-silico protein–ligand interaction profiler (PLIP) analysis, molecular docking, and in vitro studies. The screening of PLIP profiles between vorinostat/panobinostat and HDACs/LTA4H followed by molecular docking resulted in five (Sacubitrilat, B65, BDS, BIR, and NPV) FDA-approved, experimental and investigational drugs. Sacubitrilat has demonstrated promising anticancer activity against colorectal cancer (SW-480) and triple-negative breast cancer (MDA-MB-231) cells, with IC50values of 14.07 μg/mL and 23.02 μg/mL, respectively. FACS analysis revealed that sacubitrilat arrests the cell cycle at the G0/G1 phase and induces apoptotic-mediated cell death in SW-480 cells. In addition, sacubitrilat inhibited HDAC isoforms at the transcriptomic level by 0.7–0.9 fold and at the proteomic level by 0.5–0.6 fold as compared to the control. Sacubitrilat increased the protein expression of tumor-suppressor (p53) and pro-apoptotic makers (Bax and Bid) by 0.2–2.5 fold while decreasing the expression of anti-apoptotic Bcl2 and Nrf2 proteins by 0.2–0.5 fold with respect to control. The observed cleaved PARP product indicates that sacubitrilat induces apoptotic-mediated cell death. This study may pave the way to identify the anticancer potential of sacubitrilat and can be explored in human clinical trials.
An efficient single shot detector with weight-based feature fusion for small object detection
Authors: Li Ming , Pi Dechang , Qin Shuo
Published: June 2023

Object detection has been widely applied in various fields with the rapid development of deep learning in recent years. However, detecting small objects is still a challenging task because of the limited information in features and the complex background. To further enhance the detection accuracy of small objects, this paper proposes an efficient single-shot detector with weight-based feature fusion (WFFA-SSD). First, a weight-based feature fusion block is designed to adaptively fuse information from several multi-scale feature maps. The feature fusion block can exploit contextual information for feature maps with large resolutions. Then, a context attention block is applied to reinforce the local region in the feature maps. Moreover, a pyramids aggregation block is applied to combine the two feature pyramids to classify and locate target objects. The experimental results demonstrate that the proposed WFFA-SSD achieves higher mean Average Precision (mAP) under the premise of ensuring real-time performance. WFFA-SSD increases the mAP of the car by 4.12% on the test set of the CARPK.
Nanosilica treatment enables moisture-resistant hydrophobic arc welding covered electrodes
Authors: Pasandeh Mohammadreza , Pouranvari Majid
Published: June 2023

Controlling the moisture content of the electrode-covering is crucial in the production of defect-free, high-quality welds during shielded metal arc welding of steels. The welding industry has long faced the challenge of the high susceptibility of basic electrodes (e.g., E7018) to moisture absorption. In this paper, we demonstrate that applying a nanosilica coating to the surface of the E7018 electrode-covering using a dip-coating technique can effectively reduce the moisture absorption capability of the electrode-covering. The moisture measurement results before and after exposure to a moist environment of 80% humidity and a temperature of 27 °C for 9 h indicate that the moisture absorption values of conventional and nano-treated E7018 electrodes during exposure are 0.67 wt% and 0.03 wt%, respectively. While reducing the size of the pores on the surface of the electrode-covering can to some extent enhance the resistance to moisture absorption, it has been identified that turning the wetting behavior of the electrode-covering surface from hydrophilic to hydrophobic by the nanosilica coating is the most effective mechanism that contributes to the enhanced moisture absorption resistance of the nanosilica-treated electrode-covering. The results indicate that this approach does not have any deleterious effects on the chemical analysis and tensile properties of the weld metal. This simple modification to the electrode-covering can be generally applied to a wide range of electrode-covering types to produce hydrophobic, moisture-resistant electrodes.
Recovery of fuel from real waste oily sludge via a new eco-friendly surfactant material used in a digital baffle batch extraction unit
Authors: Humadi Jasim I. , Jafar Saad A. , Ali Nisreen S. , Ahmed Mustafa A. , Mzeed Mohammed J. , Al-Salhi Raheem J. , Saady Noori M. Cata , Majdi Hasan Sh. , Zendehboudi Sohrab , Albayati Talib M.
Published: June 2023

This study focused on developing a new cocktail extraction agent (CEA) composed of solvent and a new surfactant material (SM) for enhancing the efficiency of fuel recovery from real waste oil sludge (WSO). The effects of different solvents (e.g. methyl ethyl ketone (MEK), naphtha, petrol and kerosene), SMs (Dowfax and sodium thiosulfate), extraction time (10–20 min), extraction temperatures (20–60 °C) and CEA/sludge ratios (1–4) on the extraction performance were investigated. SMs and DBBE design enhanced the extraction efficiency by increasing the dispersion of solvent in WSO and enhancing the mixing and mass transfer rates. Results proved that Dowfax was the best SM for oil recovery under various conditions. The best CEA (e.g. MEK and Dowfax) provides the maximum fuel recovery rate of 97% at a period of 20 min, temperature of 60 °C and 4:1 CEA/sludge ratio. The produced fuel was analysed and fed to the distillation process to produce diesel oil. The characteristics of diesel oil were measured, and findings showed that it needs treatment processes prior its use as a finished fuel.
In-vivo corneal confocal microscopy: Imaging analysis, biological insights and future directions
Authors: Chiang Jeremy Chung Bo , Roy Maitreyee , Kim Juno , Markoulli Maria , Krishnan Arun V.
Published: June 2023

In-vivo corneal confocal microscopy is a powerful imaging technique which provides clinicians and researcher with the capabilities to observe microstructures at the ocular surfaces in significant detail. In this Mini Review, the optics and image analysis methods with the use of corneal confocal microscopy are discussed. While novel insights of neuroanatomy and biology of the eyes, particularly the ocular surface, have been provided by corneal confocal microscopy, some debatable elements observed using this technique remain and these are explored in this Mini Review. Potential improvements in imaging methodology and instrumentation are also suggested.
Inhibition of the voltage-gated potassium channel Kv1.5 by hydrogen sulfide attenuates remodeling through S-nitrosylation-mediated signaling
Authors: Al-Owais Moza M. , Hettiarachchi Nishani T. , Dallas Mark L. , Scragg Jason L. , Lippiat Jonathan D. , Holden Arun V. , Steele Derek S. , Peers Chris
Published: June 2023

The voltage-gated K+ channel plays a key role in atrial excitability, conducting the ultra-rapid rectifier K+ current (IKur) and contributing to the repolarization of the atrial action potential. In this study, we examine its regulation by hydrogen sulfide (H2S) in HL-1 cardiomyocytes and in HEK293 cells expressing human Kv1.5. Pacing induced remodeling resulted in shorting action potential duration, enhanced both Kv1.5 channel and H2S producing enzymes protein expression in HL-1 cardiomyocytes. H2S supplementation reduced these remodeling changes and restored action potential duration through inhibition of Kv1.5 channel. H2S also inhibited recombinant hKv1.5, lead to nitric oxide (NO) mediated S-nitrosylation and activated endothelial nitric oxide synthase (eNOS) by increased phosphorylation of Ser1177, prevention of NO formation precluded these effects. Regulation of Ikur by H2S has important cardiovascular implications and represents a novel and potential therapeutic target.
Variable-order topological insulators
Authors: Yang Yating , Sun Handa , Lu Jiuyang , Huang Xueqin , Deng Weiyin , Liu Zhengyou
Published: June 2023

Topological insulators, either the first-order or the higher-order, experience generally a transition to a trivial phase or a topological one of the same order through the gap closing and reopening procedure. Here, we report a topological insulator, which switches directly between the first and higher orders, with only varying the hoppings and without breaking the symmetry. The phase transition of the first and higher orders is originated from a competition mechanism between the nearest and second-nearest neighbor interactions. This variable-order topological insulator is implemented in a two-dimensional phononic crystal, and the one-dimensional helical edge states, which signal the first-order phase, and the zero-dimensional corner states, which signal the second-order one, are demonstrated in the simulations and experiments. Our study gives insight to the topological states of different orders.
Constructing soils for climate-smart mining
Authors: Ruiz Francisco , Safanelli José Lucas , Perlatti Fabio , Cherubin Maurício Roberto , Demattê José A. M. , Cerri Carlos Eduardo Pellegrino , Otero Xosé Luis , Rumpel Cornelia , Ferreira Tiago Osório
Published: June 2023

Surface mining is inherently linked to climate change, but more precise monitoring of carbon dioxide (CO2) emissions is necessary. Here we combined the geolocation of mine sites and carbon stock datasets to show that if all legal active mining sites in Brazil are exploited over the next decades, 2.55 Gt of CO2 equivalent (CO2eq) will be emitted due to the loss of vegetation (0.87 Gt CO2eq) and soil (1.68 Gt CO2eq). To offset these emissions, we propose constructing soils (Technosols) from mine and other wastes for mine reclamation. We show that this strategy could potentially offset up to 60% (1.00 Gt CO2eq) of soil-related CO2 emissions. When constructed with suitable parent materials, Technosols can also restore important soil-related ecosystem services while improving waste management. The construction of healthy Technosols stands out as a promising nature-based solution towards carbon-neutral mining and should, therefore, be considered in future environmental policies of major mining countries.
Decadal increase in groundwater inorganic carbon concentrations across Sweden
Authors: Klaus Marcus
Published: June 2023

Groundwater is one of the largest continental carbon reservoirs and tightly linked to globally important carbon fluxes such as uptake on land, degassing from inland waters and delivery to oceans. Despite emerging evidence that these fluxes are sensitive to environmental changes, long-term carbon dynamics in groundwater remain widely unknown. Here I show that dissolved inorganic carbon and carbon dioxide concentrations in groundwater, calculated from environmental monitoring data (e.g. alkalinity, pH), have increased on average by 28% and 49%, respectively, across Sweden during 1980–2020. I attribute the observed changes mainly to a partial recovery from atmospheric sulfate deposition and associated shifts in weathering pathways, but also to enhanced soil respiration. The results highlight previously neglected long-term and large-scale dynamics in groundwater carbon cycling. These dynamics should be included in carbon cycle models for accurate evaluations and predictions of the effects of environmental changes on landscape and global carbon stocks and fluxes.
Evolutionary implications of SARS-CoV-2 vaccination for the future design of vaccination strategies
Authors: Rouzine Igor M. , Rozhnova Ganna
Published: June 2023

Once the first SARS-CoV-2 vaccine became available, mass vaccination was the main pillar of the public health response to the COVID-19 pandemic. It was very effective in reducing hospitalizations and deaths. Here, we discuss the possibility that mass vaccination might accelerate SARS-CoV-2 evolution in antibody-binding regions compared to natural infection at the population level. Using the evidence of strong genetic variation in antibody-binding regions and taking advantage of the similarity between the envelope proteins of SARS-CoV-2 and influenza, we assume that immune selection pressure acting on these regions of the two viruses is similar. We discuss the consequences of this assumption for SARS-CoV-2 evolution in light of mathematical models developed previously for influenza. We further outline the implications of this phenomenon, if our assumptions are confirmed, for the future design of SARS-CoV-2 vaccination strategies.
Real-time 4D tracking of airborne virus-laden droplets and aerosols
Authors: Pal Devendra , Amyot Marc , Liang Chen , Ariya Parisa A.
Published: June 2023

There is currently no real-time airborne virus tracking method, hindering the understanding of rapid virus changes and associated health impacts. Nano-digital in-line holographic microscopy (Nano-DIHM) is a lensless technology that can directly obtain the interference patterns of objects by recording the scattered light information originating from the objects. Here, we provide evidence for real-time physicochemical tracking of virus-laden droplets and aerosols in the air using desktop label-free Nano-DIHM. The virus interference patterns, as single and ensemble particles, were imaged by the Nano-DIHM with 32.5 ms resolution. The next-generation Stingray and Octopus software was used to automate object detection, characterization and classification from the recorded holograms. The detection system was demonstrated to detect active MS2 bacteriophages, inactivated SARS-CoV-2 and RNA fragments, and an MS2 mixture with metallic and organic compounds. This work demonstrates the feasibility of using Nano-DIHM to provide rapid virus detection to improve transmission management in real time.
Computational study of native defects and defect migration in wurtzite AlN: an atomistic approach
Authors: Zhu Lei , Catlow C. Richard A. , Hou Qing , Zhang Xingfan , Buckeridge John , Sokol Alexey A.
Published: June 2023

We derive an empirical, lattice energy consistent interatomic force field model for wurtzite AlN to predict consistently a wide range of physical and defect properties.
57Fe Mössbauer and DFT study of the electronic and spatial structures of the iron(ii) (pseudo)clathrochelates: the effect of ligand field strength
Authors: Balatskiy Denis V. , Chuprin Alexander S. , Dudkin Semyon V. , Desdin-Garcia Luis Felipe , Corcho-Valdes Angel Luis , Antuch Manuel , Buznik Vyacheslav M. , Bratskaya Svetlana Yu. , Voloshin Yan Z.
Published: June 2023

Combined experimental 57Fe Mössbauer and theoretical DFT study of iron(ii) (pseudo)clathrochelates was performed. Molecular design of (pseudo)encapsulating ligands allows us to control their spin state and redox characteristics.
Feature selection in molecular graph neural networks based on quantum chemical approaches
Authors: Yokogawa Daisuke , Suda Kayo
Published: June 2023

Feature selection is an important topic that has been widely studied in data science.
Visible-light-driven organic oxidation over CdS-doped metal–organic frameworks
Authors: Bai Fengkun , Li Hanning , Jing Xu , Duan Chunying
Published: June 2023

A CdS-x(x= 1–4)@DUT-52 heterogeneous photocatalyst was constructed, which exhibits high catalytic efficiency in the photocatalytic oxidative coupling of benzylamine, oxidation of methylphenyl sulfide, and oxidation of benzyl alcohol.
Revealing unbound β-diketiminate anions: structural dynamics from caesium complexes
Authors: Videa Hellen , Martínez-Martínez Antonio J.
Published: June 2023

Setting β-diketiminate ligands free: Unveiling the unbound dynamic nature of free-form β-diketiminate anions.
Influence of sugarcane bagasse fibre on the properties of sweet lime peel- and polyvinyl alcohol-based biodegradable films
Authors: Singha Pooja , Rani Ruchi , Badwaik Laxmikant S.
Published: June 2023

Sugarcane bagasse is a readily available agro-waste, it has a potential to be used as a composite material ingredient for development of biodegradable film.
Insights into soft short circuit-based degradation of lithium metal batteries
Authors: Menkin Svetlana , Fritzke Jana B. , Larner Rebecca , de Leeuw Cas , Choi Yoonseong , Gunnarsdóttir Anna B. , Grey Clare P.
Published: June 2023

A considerable performance gap between Li symmetric cells and practical Li batteries motivated us to explore the correlation between the shape of voltage traces and degradation.
Moderate red wine intake and cardiovascular health protection: a literature review
Authors: Serio Francesca , Imbriani Giovanni , Acito Mattia , Moretti Massimo , Fanizzi Francesco Paolo , De Donno Antonella , Valacchi Giuseppe
Published: June 2023

Moderate red wine intake improves cardiovascular health by reducing oxidative stress, and playing an important role on lipid and glucose metabolism.
Capsicum chinense var. BRS Moema: chemical characterization by HPLC-ESI-MS/MS and antiproliferative screening
Authors: de Aguiar Ana Carolina , Pereira Gustavo Araujo , Ribeiro Cláudia Silva da Costa , Eberlin Marcos Nogueira , Soares Lana Pereira , Ruiz Ana Lucia Tasca Gois , Pastore Glaucia Maria , Martínez Julian
Published: June 2023

BRS Moema showed considerable quantities of capsiate and phenolic compounds (in free, esterified, glycosylated, and insoluble-bound forms) quantified by UHPLC-ESI-MS/MS.
Selective recognition of neurotransmitters in aqueous solution by hydroxyphenyl aza-scorpiand ligands
Authors: Verdejo Begoña , Inclán Mario , Blasco Salvador , Ballesteros-Garrido Rafael , Savastano Matteo , Bianchi Antonio , García-España Enrique
Published: June 2023

Anion recognition of neurotransmitters (dopamine, tyramine and serotonin) in aqueous solution of different aza-scorpiand ligands have been studied by potentiometry, NMR, UV-Vis and fluorescence spectroscopy and isothermal titration calorimetry (ITC).
Copper catalysed oxidative cascade deamination/cyclization of vinyl azide and benzylamine for the synthesis of 2,4,6-triarylpyridines
Authors: Chatterjee Rana , Bhukta Swadhapriya , Angajala Kishore Kumar , Dandela Rambabu
Published: June 2023

An efficient method has been developed to access diverse 2,4,6-triarylpyridines via oxidative cascade cyclization of vinyl azide and benzylamine promoted by a copper(ii) and iodine system.
Pd-catalyzed homo-coupling of benzofurans: one-pot synthesis of diverse 3,3′-bisbenzofurans
Authors: Gugulothu Kishan , Jatoth Ramanna , Gudipati Ramakrishna , Rajitha Nampally , Dandela Rambabu , Shiva Kumar K.
Published: June 2023

An effective and one-pot Pd-catalysed synthesis of 3,3′-bisbenzofuran derivatives via dehydrogenative homo-coupling of benzofurans, which tolerated various functional groups affording good yields, is reported.
Total synthesis, structure elucidation and expanded bioactivity of icosalide A: effect of lipophilicity and ester to amide substitution on its bioactivity
Authors: Dangi Abha , Pande Bharat , Agrawal Sonia , Sarkar Dhiman , Vamkudoth Koteswara Rao , Marelli Udaya Kiran
Published: June 2023

Synthesis, stereo assignment and NMR based three-dimensional conformation of depsipeptide Icosalide A were achieved. SAR study of Icosalide A and its analogues varying in β-hydroxy acids was investigated, further establishing their antituberculosis and anticancer activity.
Balancing “on” and “off” response of hydroxyl groups to a nanozyme-catalyzing system for the construction of an ultra-sensitive and selective “signal-on” detection platform for dopamine
Authors: Lan Hongmei , Li Gaoya , Chen Guo , Ding Mengyao , Xiao Shuangling , Xiang Jianglin , Duan Xingwu , Cao Haiyan , Shi Wenbing , Dong Wenfei
Published: June 2023

By balancing the “signal-on” effect in less DA and “signal-off” effect in excess DA, the “signal-on” mode for the detection of DA was proposed with higher sensitivity and selectivity.
Pressure-induced postsynthetic cluster anion substitution in a MIL-53 topology scandium metal–organic framework
Authors: Thom Alexander J. R. , Turner Gemma F. , Davis Zachary H. , Ward Martin R. , Pakamorė Ignas , Hobday Claire L. , Allan David R. , Warren Mark R. , Leung Wai L. W. , Oswald Iain D. H. , Morris Russell E. , Moggach Stephen A. , Ashbrook Sharon E. , Forgan Ross S.
Published: June 2023

Application of pressure induces reactivity of pore-bound methanol with the secondary building unit of the metal–organic framework GUF-1(Sc), substituting coordinated bridging hydroxide ligands for bridging methoxides, in single crystals and in bulk.
Crossover behavior in stress relaxations of poroelastic and viscoelastic dominant hydrogels
Authors: Li Hangyu , Lian Xinyi , Guan Dongshi
Published: June 2023

AFM measurement reveals that two distinct mechanisms determine the crossover phenomenon in the stress relaxation of hydrogels. This contributes to a better understanding of similar mechanical behaviors of cells and tissues.
Graphene oxide and low-density polyethylene based highly sensitive biomimetic soft actuators powered by multiple clean energies of humidity and light
Authors: Zhang Yiwei , Wang Ruiqian , Tan Wenjun , Yang Lianchao , Lv Xiaolong , Wang Xiaodong , Wang Feifei , Zhang Chuang
Published: June 2023

A biomimetic soft actuator with ultrahigh sensitivity and multi-responsive characteristics is proposed, which can make full use of the clean energies of light and humidity in nature for various of bionic and engineering designs.
Structural factors for activating anionic redox in Li-rich Ti-based cathodes
Authors: Kwon Dohyeong , Kim Duho
Published: June 2023

A systematic investigation of anionic redox activities for Li-rich Ti-based cathode models depending on their crystal structures and anions is performed to harness the full potential of the anionic capacity in lithium-ion batteries.
Next generation thermal insulators for operation in high-temperature and humid environments through aerogel carbonization
Authors: Alshrah Mohammed , Mark Lun Howe , Buahom Piyapong , Lee Jung Hyub , Rezaei Sasan , Naguib Hani E. , Park Chul B.
Published: June 2023

Successful carbonization of an RF aerogel to generate a carbon aerogel. Integration of hydrogen gas during the carbonization process of the carbon aerogel. Fabrication of the moisture resistance aerogel for thermal insulation applications.
Microstructure controllable polyimide/MXene composite aerogels for high-temperature thermal insulation and microwave absorption
Authors: Zhang Wenting , Ding Enjie , Zhang Wenxi , Li Jiaqiang , Luo Chuyang , Zhang Liying
Published: June 2023

High-temperature thermal insulation and microwave absorption performance of PI/MXene composite aerogels.
A centimeter-scaled lead-free two-dimensional perovskite FA3Bi2Br9single crystal for X-ray detection
Authors: Luo Xiuting , Gao Lei , Tao Kezheng , Li Qiang , Yan Qingfeng
Published: June 2023

A centimeter-sized FA3Bi2Br9single crystal was grown and the X-ray detector demonstrated a high sensitivity of 623 μC Gy−1cm−2and a low detection limit of 2.1 μGy s−1.
Ternary alloyed MoS2–xSex nanocomposites with a carrier mobility-dominated gas sensing mode: a superior room temperature gas sensing material for NO2 sensors
Authors: Yin Mingli , Wang Kexin , Zhang Liaochuan , Gao Chunxiao , Ren Juan , Yu Lingmin
Published: June 2023

For gas sensors, the carrier mobility-dominated gas sensing mode is more progressive than the traditional mode, which can get rid of the limitation of carrier concentration and adjust the conductivity in a wider range.
Commentary on: Divalent metal cofactors differentially modulate RadA-mediated strand invasion and exchange in Saccharolobus solfataricus
Authors: Mangialavori Irene C.
Published: June 2023

RecA ATPases are a family of proteins that catalyzes the exchange of complementary DNA regions via homologous recombination. They are conserved from bacteria to humans and are crucial for DNA damage repair and genetic diversity. In this work, Knadler et al. examine how ATP hydrolysis and divalent cations impact the recombinase activity of Saccharolobus solfataricus RadA protein (ssoRadA). They find that the ssoRadA-mediated strand exchange depends on ATPase activity. The presence of Manganese reduces ATPase activity and enhances strand exchange, while calcium inhibits ATPase activity by preventing ATP binding to the protein, yet destabilizes the nucleoprotein ssoRadA filaments, allowing strand exchange regardless of the ATPase activity. Although RecA ATPases are highly conserved, this research offers intriguing new evidence that each member of the family requires individual evaluation.
Harnessing extremophilic carboxylesterases for applications in polyester depolymerisation and plastic waste recycling
Authors: Williams Gwion B. , Ma Hairong , Khusnutdinova Anna N. , Yakunin Alexander F. , Golyshin Peter N.
Published: June 2023

The steady growth in industrial production of synthetic plastics and their limited recycling have resulted in severe environmental pollution and contribute to global warming and oil depletion. Currently, there is an urgent need to develop efficient plastic recycling technologies to prevent further environmental pollution and recover chemical feedstocks for polymer re-synthesis and upcycling in a circular economy. Enzymatic depolymerization of synthetic polyesters by microbial carboxylesterases provides an attractive addition to existing mechanical and chemical recycling technologies due to enzyme specificity, low energy consumption, and mild reaction conditions. Carboxylesterases constitute a diverse group of serine-dependent hydrolases catalysing the cleavage and formation of ester bonds. However, the stability and hydrolytic activity of identified natural esterases towards synthetic polyesters are usually insufficient for applications in industrial polyester recycling. This necessitates further efforts on the discovery of robust enzymes, as well as protein engineering of natural enzymes for enhanced activity and stability. In this essay, we discuss the current knowledge of microbial carboxylesterases that degrade polyesters (polyesterases) with focus on polyethylene terephthalate (PET), which is one of the five major synthetic polymers. Then, we briefly review the recent progress in the discovery and protein engineering of microbial polyesterases, as well as developing enzyme cocktails and secreted protein expression for applications in the depolymerisation of polyester blends and mixed plastics. Future research aimed at the discovery of novel polyesterases from extreme environments and protein engineering for improved performance will aid developing efficient polyester recycling technologies for the circular plastics economy.
Overview of frequency control techniques in power systems with high inverter‐based resources: Challenges and mitigation measures
Authors: Al Kez Dlzar , Foley Aoife M. , Ahmed Faraedoon , Morrow D. John
Published: June 2023

Power systems are rapidly transitioning towards having an increasing proportion of electricity from inverter‐based resources (IBR) such as wind and solar. An inevitable consequence of a power system transition towards 100% IBR is the loss of synchronous generators with their associated inertia, frequency, and voltage control mechanisms. To ensure future grid needs can be met, the source of system services to meet these needs must change from synchronous plants to IBR. Under this context, the main objective is to extensively review grid frequency stability challenges concerning the massive integration of IBR from the perspective of system operators. Following that, the newly established international fast frequency response services in different renewable dominant power systems to address low inertia challenges are compared from various perspectives. Finally, potential solutions based on various renewable enabling technologies and renewable sources are investigated from the standpoint of their expectation to play an active role in the energy system and to provide a wide range of system frequency services. The findings of this study provide a deep understanding of prospective frequency control solutions and an actionable dataset that will support various research and policy needs as we approach net‐zero targets.
Identification of a 4.3 billion year old asteroid family and planetesimal population in the Inner Main Belt
Authors: Ferrone S. , Delbo M. , Avdellidou C. , Melikyan R. , Morbidelli A. , Walsh K. , Deienno R.
Published: June 2023

Context. Understanding the conditions that lead to the formation of planetesimals – the building blocks of planets - and their initial size distribution is a central problem of modern planetology. While most of these original planetesimals were accreted onto the terrestrial planets and the cores of the giant planets, some were also stranded in the main belt, where 4.5 Gyr of collisional evolution broke most of them into families of collisional asteroid fragments. However, some planetesimals survived, and are still hidden amongst asteroid fragments in the main belt.

Aims. We make use of astronomical data to identify these leftover planetesimals amongst all other asteroids. Our search is based on separating planetesimal survivors from families of asteroids generated by collisions. Namely, we aim to identify and “clean” the main belt of collisional family members: by doing so, we would be left with the surviving members of the original planetesimals.

Methods. We focus here on the inner portion of the main belt for asteroids with intermediate to high albedo. It is known that current asteroid family catalogs are not suitable for the aforementioned cleaning; they are conservative and only one-quarter of the known asteroids are associated with the approximately 120 distinct asteroid families. We therefore developed methods to inclusively link asteroids to known collisional families in order to better capture their extent. Namely, we apply a hierarchical clustering method (HCM) on asteroids filtered according to the V-shape of the Yarkovsky drift of each family in order to reassess family membership (V-shape-constrained HCM). The identified families were removed and the remaining background population was searched for previously undetected collisional families.

Results. We succeed in using our V-shape-constrained HCM to link family “halos” to their cores. After removing these reassessed families from the asteroid population, our V-shape search reveals a previously unknown collisional family of S-type asteroids in the inner main belt with an age of 4.3 ± 1.7 Gyr and a significance level of 3.4σ. When this ancient collisional family is removed, 34 planetesimals are identified and their size-frequency distribution is presented.

Conclusions. The asteroid belt has two components: planetesimals and collisional fragments. The cumulative size-frequency distribution of planetesimals has a steep power-law index for bodies larger than 100 km in diameter and a much smaller power-law index for planetesimals smaller than 100 km.
Extreme-ultraviolet brightenings in the quiet Sun: Signatures in spectral and imaging data from the Interface Region Imaging Spectrograph
Authors: Nelson C. J. , Auchère F. , Aznar Cuadrado R. , Barczynski K. , Buchlin E. , Harra L. , Long D. M. , Parenti S. , Peter H. , Schühle U. , Schwanitz C. , Smith P. , Teriaca L. , Verbeeck C. , Zhukov A. N. , Berghmans D.
Published: June 2023

Context. Localised transient EUV brightenings, sometimes named ‘campfires’, occur throughout the quiet Sun. However, there are still many open questions about these events, in particular regarding their temperature range and dynamics.

Aims. We aim to determine whether any transition region response can be detected for small-scale extreme-ultraviolet (EUV) brightenings and, if so, to identify whether the measured spectra correspond to any previously reported bursts in the transition region, such as explosive events (EEs).

Methods. EUV brightenings were detected in a ∼29.4 min dataset sampled by the Solar Orbiter Extreme Ultraviolet Imager (EUI) on 8 March 2022 using an automated detection algorithm. Any potential transition region response was inferred through analysis of imaging and spectral data sampled through coordinated observations conducted by the Interface Region Imaging Spectrograph (IRIS).

Results. EUV brightenings display a range of responses in IRIS slit-jaw imager (SJI) data. Some events have clear signatures in the Mg II and Si IV SJI filters, whilst others have no discernible counterpart. Both extended and more complex EUV brightenings are sometimes found to have responses in IRIS SJI data. Examples of EUI intensities peaking before, during, and after their IRIS counterparts were found in light curves constructed co-spatial to EUV brightenings. Importantly, therefore, it is likely that not all EUV brightenings are driven in the same way, with some events seemingly being magnetic reconnection driven and others not. A single EUV brightening occurred co-spatial to the IRIS slit, with the returned spectra matching the properties of EEs.

Conclusions. EUV brightening is a term used to describe a range of small-scale events in the solar corona. The physics behind all EUV brightenings is likely not the same. More research is therefore required to assess their importance for global questions in the field, such as coronal heating.
The low surface thermal inertia of the rapidly rotating near-Earth asteroid 2016 GE1
Authors: Fenucci Marco , Novaković Bojan , Marčeta Dušan
Published: June 2023

Context. Asteroids smaller than about 100 m in diameter are observed to rotate very fast, with periods often much shorter than the critical spin limit of 2.2 h. Some of these super-fast rotators can also achieve a very large semimajor axis drift induced by the Yarkovsky effect, which, in turn, is determined by internal and surface physical properties.

Aims. We consider here a small super-fast-rotating near-Earth asteroid, designated as 2016 GE1. This object rotates in just about 34 s, and a large Yarkovsky effect has been determined from astrometry. By using these results, we aim to constrain the thermal inertia of the surface of this extreme object.

Methods. We used a recently developed statistical method to determine the thermal properties of near-Earth asteroids. The method is based on the comparison between the observed and the modeled Yarkovsky effect, and the thermal conductivity (inertia) is determined via a Monte Carlo approach. Parameters of the Yarkovsky effect model are fixed if their uncertainty is negligible, modeled with a Gaussian distribution of the errors if they are measured, or deduced from general properties of the population of near-Earth asteroids when they are unknown.

Results. Using a well-established orbit determination procedure, we determined the Yarkovsky effect on 2016 GE1 and confirm a significant semimajor axis drift rate. Using a statistical method, we show that this semimajor axis drift rate can only be explained by low thermal inertia values below 100 J m−2 K−1 s−1/2. We benchmarked our statistical method using the well-characterized asteroid Bennu and find that only knowing the semimajor axis drift rate and the rotation period is generally insufficient for determining the thermal inertia. However, when the statistical method is applied to super-fast rotators, we find that the measured Yarkovsky effect can be achieved only for very low values of thermal inertia: namely, 90% of the probability density function of the model outcomes is contained at values smaller than 100 J m−2 K−1 s−1/2.

Conclusions. We propose two possible interpretations for the extremely low thermal inertia of 2016 GE1: a high porosity or a cracked surface, or a thin layer of fine regolith on the surface. Though both possibilities seem somewhat unexpected, this opens up the possibility of a subclass of low-inertia, super-fast-rotating asteroids.
Dynamical detection of a companion driving a spiral arm in a protoplanetary disk
Authors: Xie Chen , Ren Bin B. , Dong Ruobing , Choquet Élodie , Vigan Arthur , Gonzalez Jean-François , Wagner Kevin , Fang Taotao , Ubeira-Gabellini Maria Giulia
Published: June 2023

Radio and near-infrared observations have observed dozens of protoplanetary disks that host spiral arm features. Numerical simulations have shown that companions may excite spiral density waves in protoplanetary disks via companion–disk interaction. However, the lack of direct observational evidence for spiral-driving companions poses challenges to current theories of companion–disk interaction. Here we report multi-epoch observations of the binary systemHD 100453with the Spectro-Polarimetric High-contrast Exoplanet REsearch (SPHERE) facility at the Very Large Telescope. By recovering the spiral features via robustly removing starlight contamination, we measure spiral motion across 4 yr to perform dynamical motion analyses. The spiral pattern motion is consistent with the orbital motion of the eccentric companion. With this first observational evidence of a companion driving a spiral arm among protoplanetary disks, we directly and dynamically confirm the long-standing theory on the origin of spiral features in protoplanetary disks. With the pattern motion of companion-driven spirals being independent of companion mass, here we establish a feasible way of searching for hidden spiral-arm-driving planets that are beyond the detection of existing ground-based high-contrast imagers.
Structure of iso-density sets in supersonic isothermal turbulence
Authors: Thiesset F. , Federrath C.
Published: June 2023

Context. The gas density structure of the cold molecular phase of the interstellar medium is the main controller of star formation.

Aims. A theoretical framework is proposed to describe the structural content of the density field in isothermal supersonic turbulence.

Methods. It makes use of correlation and structure functions of the phase indicator field defined for different iso-density values. The relations between these two-point statistics and the geometrical features of iso-density sets such as the volume fraction, the surface density, the curvature, and fractal characteristics are provided. An exact scale-by-scale budget equation is further derived revealing the role of the turbulent cascade and dilation on the structural evolution of the density field. Although applicable to many flow situations, this tool is here first invoked for characterising supersonic isothermal turbulence, using data from the currently best-resolved numerical simulation.

Results. We show that iso-density sets are surface fractals rather than mass fractals, with dimensions that markedly differ between dilute, neutral, and dense regions. The surface–size relation is established for different iso-density values. We further find that the turbulent cascade of iso-density sets is directed from large towards smaller scales, in agreement with the classical picture that turbulence acts to concentrate more surface into smaller volumes. Intriguingly, there is no range of scales that complies with a constant transfer rate in the cascade, challenging our fundamental understanding of interstellar turbulence. Finally, we recast the virial theorem in a new formulation drawing an explicit relation between the aforementioned geometrical measures and the dynamics of iso-density sets.
Expanding the inventory of spectral lines used to trace atmospheric escape in exoplanets
Authors: Linssen D. C. , Oklopčić A.
Published: June 2023

Escaping exoplanet atmospheres have been observed as deep transit signatures in a few specific spectral lines. Detections have been made in the hydrogen Ly-αline, the metastable helium line at 10 830 Å, and some UV lines of metallic species. Observational challenges, unexpected nondetections, and model degeneracies have generally made it difficult to draw definitive conclusions about the escape process for individual planets. Expanding on the suite of spectral tracers used may help to mitigate these challenges. We present a new framework for modeling the transmission spectrum of hydrodynamically escaping atmospheres. We predict far UV to near infrared spectra for systems with different planet and stellar types and identify new lines that can potentially be used to study their upper atmospheres. Measuring the radius in the atmosphere at which the strongest lines form puts them into context within the upper atmospheric structure. Targeting a set of complementary spectral lines for the same planet will help us to better constrain the outflow properties.