bluuebunny/crossref_metadata_2025 huggingface dataset:
Akkermansia muciniphila Alleviates Persistent Inflammation, Immunosuppression, and Catabolism Syndrome in Mice
Authors: Xu Yali , Duan Jianfeng , Wang Dacheng , Liu Jiali , Chen Xiancheng , Qin Xian-Yang , Yu Wenkui
Published: January 2023

Many patients in intensive care units, especially the elderly, suffer from chronic critical illness and exhibit a new pathophysiological phenotype: persistent inflammation, immunosuppression, and catabolism syndrome (PICS). Most patients with PICS have a constellation of digestive-system symptoms and gut failure. Akkermansia muciniphila (Akk) is a commensal gut bacterium that reduces inflammation, balances immune responses, modulates energy metabolism, and supports gut health. This study investigated the protective effects and underlying mechanisms of live and pasteurized Akk in treating PICS in a mouse model. PICS was induced on day 14 after performing cecal ligation and puncture (CLP) on day 1 and administrating lipopolysaccharide on day 11. Pasteurized or live Akk, or phosphate-buffered saline was administered twice daily by oral gavage for 7 days. Both live and pasteurized Akk attenuated PICS, as evidenced by reduced weight loss, and a reduction in symptoms and serum cytokine/chemokine levels. Liver and intestinal injuries were mitigated, and intestinal barrier integrity improved with Akk administration. Analysis of 16S rRNA amplicon sequences showed that Akk induced significant intestinal microbiota alterations, including increased abundance of Akk, Muribaculaceae, Parabacterbides goldsteinii, and decreased abundance of Escherichia_Shigella and Enterobacteriaceae. Collectively, Akk alleviates PICS by enhancing gut barrier function and reshaped the microbial community.
Efficient SABRE-SHEATH Hyperpolarization of Potent Branched-Chain-Amino-Acid Metabolic Probe [1-13C]ketoisocaproate
Authors: Adelabu Isaiah , Chowdhury Md Raduanul H. , Nantogma Shiraz , Oladun Clementinah , Ahmed Firoz , Stilgenbauer Lukas , Sadagurski Marianna , Theis Thomas , Goodson Boyd M. , Chekmenev Eduard Y.
Published: January 2023

Efficient 13C hyperpolarization of ketoisocaproate is demonstrated in natural isotopic abundance and [1-13C]enriched forms via SABRE-SHEATH (Signal Amplification By Reversible Exchange in SHield Enables Alignment Transfer to Heteronuclei). Parahydrogen, as the source of nuclear spin order, and ketoisocaproate undergo simultaneous chemical exchange with an Ir-IMes-based hexacoordinate complex in CD3OD. SABRE-SHEATH enables spontaneous polarization transfer from parahydrogen-derived hydrides to the 13C nucleus of transiently bound ketoisocaproate. 13C polarization values of up to 18% are achieved at the 1-13C site in 1 min in the liquid state at 30 mM substrate concentration. The efficient polarization build-up becomes possible due to favorable relaxation dynamics. Specifically, the exponential build-up time constant (14.3 ± 0.6 s) is substantially lower than the corresponding polarization decay time constant (22.8 ± 1.2 s) at the optimum polarization transfer field (0.4 microtesla) and temperature (10 °C). The experiments with natural abundance ketoisocaproate revealed polarization level on the 13C-2 site of less than 1%—i.e., one order of magnitude lower than that of the 1-13C site—which is only partially due to more-efficient relaxation dynamics in sub-microtesla fields. We rationalize the overall much lower 13C-2 polarization efficiency in part by less favorable catalyst-binding dynamics of the C-2 site. Pilot SABRE experiments at pH 4.0 (acidified sample) versus pH 6.1 (unaltered sodium [1-13C]ketoisocaproate) reveal substantial modulation of SABRE-SHEATH processes by pH, warranting future systematic pH titration studies of ketoisocaproate, as well as other structurally similar ketocarboxylate motifs including pyruvate and alpha-ketoglutarate, with the overarching goal of maximizing 13C polarization levels in these potent molecular probes. Finally, we also report on the pilot post-mortem use of HP [1-13C]ketoisocaproate in a euthanized mouse, demonstrating that SABRE-hyperpolarized 13C contrast agents hold promise for future metabolic studies.
Association between Circulating Amino Acids and COVID-19 Severity
Authors: Maltais-Payette Ina , Lajeunesse-Trempe Fannie , Pibarot Philippe , Biertho Laurent , Tchernof André
Published: January 2023

The severity of the symptoms associated with COVID-19 is highly variable, and has been associated with circulating amino acids as a group of analytes in metabolomic studies. However, for each individual amino acid, there are discordant results among studies. The aims of the present study were: (i) to investigate the association between COVID-19-symptom severity and circulating amino-acid concentrations; and (ii) to assess the ability of circulating amino-acid levels to predict adverse outcomes (intensive-care-unit admission or hospital death). We studied a sample of 736 participants from the Biobanque Québécoise COVID-19. All participants tested positive for COVID-19, and the severity of symptoms was determined using the World-Health-Organization criteria. Circulating amino acids were measured by HPLC-MS/MS. We used logistic models to assess the association between circulating amino acids concentrations and the odds of presenting mild vs. severe or mild vs. moderate symptoms, as well as their accuracy in predicting adverse outcomes. Patients with severe COVID-19 symptoms were older on average, and they had a higher prevalence of obesity and type 2 diabetes. Out of 20 amino acids tested, 16 were significantly associated with disease severity, with phenylalanine (positively) and cysteine (inversely) showing the strongest associations. These associations remained significant after adjustment for age, sex and body mass index. Phenylalanine had a fair ability to predict the occurrence of adverse outcomes, similar to traditionally measured laboratory variables. A multivariate model including both circulating amino acids and clinical variables had a 90% accuracy at predicting adverse outcomes in this sample. In conclusion, patients presenting severe COVID-19 symptoms have an altered amino-acid profile, compared to those with mild or moderate symptoms.
Non-Invasive Lung Cancer Diagnostics through Metabolites in Exhaled Breath: Influence of the Disease Variability and Comorbidities
Authors: Temerdashev Azamat Z. , Gashimova Elina M. , Porkhanov Vladimir A. , Polyakov Igor S. , Perunov Dmitry V. , Dmitrieva Ekaterina V.
Published: January 2023

Non-invasive, simple, and fast tests for lung cancer diagnostics are one of the urgent needs for clinical practice. The work describes the results of exhaled breath analysis of 112 lung cancer patients and 120 healthy individuals using gas chromatography-mass spectrometry (GC-MS). Volatile organic compound (VOC) peak areas and their ratios were considered for data analysis. VOC profiles of patients with various histological types, tumor localization, TNM stage, and treatment status were considered. The effect of non-pulmonary comorbidities (chronic heart failure, hypertension, anemia, acute cerebrovascular accident, obesity, diabetes) on exhaled breath composition of lung cancer patients was studied for the first time. Significant correlations between some VOC peak areas and their ratios and these factors were found. Diagnostic models were created using gradient boosted decision trees (GBDT) and artificial neural network (ANN). The performance of developed models was compared. ANN model was the most accurate: 82–88% sensitivity and 80–86% specificity on the test data.
Dietary Administration of Black Raspberries and Arsenic Exposure: Changes in the Gut Microbiota and Its Functional Metabolites
Authors: Tu Pengcheng , Tang Qiong , Mo Zhe , Niu Huixia , Hu Yang , Wu Lizhi , Chen Zhijian , Wang Xiaofeng , Gao Bei
Published: January 2023

Mounting evidence has linked berries to a variety of health benefits. We previously reported that administration of a diet rich in black raspberries (BRBs) impacted arsenic (As) biotransformation and reduced As-induced oxidative stress. To further characterize the role of the gut microbiota in BRB-mediated As toxicity, we utilized the dietary intervention of BRBs combined with a mouse model to demonstrate microbial changes by examining associated alterations in the gut microbiota, especially its functional metabolites. Results showed that BRB consumption changed As-induced gut microbial alterations through restoring and modifying the gut microbiome, including its composition, functions and metabolites. A number of functional metabolites in addition to bacterial genera were significantly altered, which may be linked to the effects of BRBs on arsenic exposure. Results of the present study suggest functional interactions between dietary administration of black raspberries and As exposure through the lens of the gut microbiota, and modulation of the gut microbiota and its functional metabolites could contribute to effects of administration of BRBs on As toxicity.
Highly Sensitive Electrochemical Endotoxin Sensor Based on Redox Cycling Using an Interdigitated Array Electrode Device
Authors: Ito Kentaro , Inoue Kumi Y. , Ito-Sasaki Takahiro , Ikegawa Miho , Takano Shinichiro , Ino Kosuke , Shiku Hitoshi
Published: January 2023

The Limulus amebocyte lysate (LAL) reaction-based assay, the most commonly used endotoxin detection method, requires a skilled technician. In this study, to develop an easy-to-use and highly sensitive endotoxin sensor, we created an electrochemical endotoxin sensor by using an interdigitated array electrode (IDAE) device with advantages of amplifiable signals via redox cycling and portability. We added Boc-Leu-Gly-Arg-p-aminophenol (LGR-pAP) as an electrochemical substrate for an LAL reaction and detected p-aminophenol (pAP) released from LGR-pAP as a product of an endotoxin-induced LAL reaction via an IDAE device. The IDAE device showed a great redox cycling efficiency of 79.8%, and a 4.79-fold signal amplification rate. Then, we confirmed that pAP was detectable in the presence of LGR-pAP through chronoamperometry with the potential of the anode stepped from −0.3 to 0.5 V vs. Ag/AgCl while the cathode was biased at −0.3 V vs. Ag/AgCl. Then, we performed an endotoxin assay by using the IDAE device. Our endotoxin sensor detected as low as 0.7 and 1.0 endotoxin unit/L after the LAL reaction for 1 h and 45 min, respectively, and these data were within the cut-off value for ultrapure dialysis fluid. Therefore, our highly sensitive endotoxin sensor is useful for ensuring medical safety.
Handling Detection Limits of Multiplex Lateral Flow Immunoassay by Choosing the Order of Binding Zones
Authors: Bartosh Anastasiya V. , Sotnikov Dmitriy V. , Zherdev Anatoly V. , Dzantiev Boris B.
Published: January 2023

Changes in the limits of detection (LODs) for a multiplex lateral flow immunoassay (LFIA) caused by different locations of the binding zone on the test strips were studied. Due to the non-equilibrium conditions of the immune reactions in LFIAs, their analytical parameters are susceptible to the binding constants of antigen–antibody reactions and assay duration. Consequently, the integration of several tests into one multiplex assay can cause a significant worsening of the sensitivity. In this study, we propose a simple methodology for the determination of the best arrangement of binding zones, which takes into account the binding constants for immunoreagents. LFIAs of four mycotoxins, namely, aflatoxin B1, deoxynivalenol, T-2 toxin, and ochratoxin A, were integrated into a multiplex test strip. An enzyme-linked immunosorbent assay was applied to determine the equilibrium and kinetic constants of the immunoreactants for each analyte. It was found that the arrangement of binding zones with a descending order of the equilibrium association constants was optimal and provided both lower detection limits and a more uniform coloration. The selected position of the binding zones allowed decreasing the LODs down to 2 and 27 times for ochratoxin A and deoxynivalenol, respectively. The proposed approach can be applied to multiplex LFIAs for different analytes.
Computational Analysis of Darcy–Forchheimer Flow of Cu/Al–Al2O3 Hybrid Nanofluid in Water over a Heated Stretchable Plate with Nonlinear Radiation
Authors: Alessa Nazek , Sindhu R. , Divya S. , Eswaramoorthi S. , Loganathan Karuppusamy , Prasad Kashi Sai
Published: January 2023

The aim of this study is to examine the Darcy–Forchheimer flow = of H2O-based Al−Al2O3/Cu−Al2O3 hybrid nanofluid past a heated stretchable plate including heat consumption/ generation and non-linear radiation impacts. The governing flow equations are formulated using the Naiver–Stokes equation. These flow equations are re-framed by using the befitted transformations. The MATLAB bvp4c scheme is utilized to compute the converted flow equations numerically. The graphs, tables, and charts display the vicissitudes in the hybrid nanofluid velocity, hybrid nanofluid temperature, skin friction coefficient, and local Nusselt number via relevant flow factors. It can be seen that the hybrid nanofluid velocity decreased as the magnetic field parameter was increased. The hybrid nanofluid temperature tended to rise as the heat absorption/generation, nanoparticle volume friction, and nonlinear radiation parameters were increased. The surface drag force decreased when the quantity of the magnetic parameter increased. The larger size of the radiation parameter led to enrichment of the heat transmission gradient.
Visible-Range Multiple-Channel Metal-Shell Rod-Shaped Narrowband Plasmonic Metamaterial Absorber for Refractive Index and Temperature Sensing
Authors: Chao Chung-Ting Chou , Kooh Muhammad Raziq Rahimi , Lim Chee Ming , Thotagamuge Roshan , Mahadi Abdul Hanif , Chau Yuan-Fong Chou
Published: January 2023

Multiple resonance modes in an optical absorber are necessary for nanophotonic devices and encounter a challenge in the visible range. This article designs a multiple-channel plasmonic metamaterial absorber (PMA) that comprises a hexagonal arrangement of metal-shell nanorods in a unit cell over a continuous thin metal layer, operating in the visible range of the sensitive refractive index (RI) and temperature applications. Finite element method simulations are utilized to investigate the physical natures, such as the absorptance spectrum, magnetic flux and surface charge densities, electric field intensity, and electromagnetic power loss density. The advantage of the proposed PMA is that it can tune either three or five absorptance channels with a narrowband in the visible range. The recorded sensitivity and figure of merit (S, FOM) for modes 1–5 can be obtained (600.00 nm/RIU, 120.00), (600.00 nm/RIU, 120.00 RIU−1), (600.00 nm/RIU, 120.00 RIU−1), (400.00 nm/RIU, 50.00 RIU−1), and (350.00 nm/RIU, 25.00 RIU−1), respectively. Additionally, the temperature sensitivity can simultaneously reach 0.22 nm/°C for modes 1–3. The designed PMA can be suitable for RI and temperature sensing in the visible range.
Influence of the Ground Electrode on the Dynamics of Electrowetting
Authors: Khan Iftekhar , Castelletto Stefania , Rosengarten Gary
Published: January 2023

The ability to manipulate a liquid meniscus using electrowetting has many applications. In any electrowetting design, at least two electrodes are required: one forms the field to change the contact angle and the other functions as a ground electrode. The contribution of the ground electrode (GE) to the dynamics of electrowetting has not yet been thoroughly investigated. In this paper, we discovered that with a bare ground electrode, the contact angle of a sessile drop increases instead of decreases when a direct current (DC) voltage varying from zero to the threshold voltage is applied. This phenomenon is opposite to what occurs when the GE is coated with a dielectric, where the contact-angle change follows the Lippmann–Young equation above the threshold voltage of electrowetting. However, this behaviour is not observed with either a dielectric-coated electrode using direct current (DC) or a bare ground electrode using alternating current (AC) voltage electrowetting. This study explains this phenomenon with finite element simulation and theory. From previous research work, the ground electrode configuration is inconsistent. In some studies, the ground electrode is exposed to water; in other studies, the ground electrode is covered with dielectric. This study identified that an exposed ground electrode is not required in electrowetting. Moreover, this research work suggests that for applications where precise control of the contact angle is paramount, a dielectric-coated ground electrode should be used since it prevents the increase in the contact angle when increasing the applied potential from zero to the threshold voltage. This study also identified that contact angle hysteresis is lower with a Cytop-coated ground electrode and DC voltage than with a bare ground electrode using AC or DC voltages.
A Dual-Axis Rotation Scheme for Redundant Rotational Inertial Navigation System
Authors: Zhu Ting , Wang Lifen , Zou Tao , Peng Gao
Published: January 2023

A redundant rotational inertial navigation system (RRINS) comprises a redundant inertial measurement unit (RIMU) and a turntable for improving reliability and navigation accuracy. Because of the multi-sensor configuration, the RIMU has a more complex error model compared with the traditional orthogonal inertial measurement unit (IMU). Therefore, the RIMU-based rotation scheme cannot simply replicate the traditional IMU-based rotation scheme. In this study, a dual-axis rotation scheme for RIMU characteristics is proposed. First, the error model of the RIMU was established, and the error compensation of RIMU caused by rotation was analyzed. Second, the principles of rotation axis switching and reciprocating rotation were summarized, and a dual-axis rotation scheme was designed by these principles. Finally, the rotation scheme was applied to an RRINS prototype consisting of RIMU (four fiber optic gyroscopes + four quartz accelerometers) and a dual-axis turntable, and then simulations and experiments were performed. The results of the simulations and experiments show that the positioning accuracy of RRINS can be obviously improved by using the proposed rotation scheme.
Intramolecular OHO Hydrogen Bonding in Dibenzoylmethane Enol: Raman Spectroscopic and Quantum Chemical Study
Authors: Kolesov Boris A. , Pritchina Elena A. , Tikhonov Aleksey Ya.
Published: January 2023

In the present work, the intramolecular O-H···O hydrogen bonding in 3-hydroxy-1,3-diphenylprop-2-en-1-one (keto-enol form of dibenzoylmethane, DBM) was investigated. For this purpose, the Raman spectra of polycrystalline samples of ordinary (H-DBM) and deuterated (D-DBM) 3-hydroxy-1,3-diphenylprop-2-en-1-one in the temperature range of 5–300 K were measured. It was found that low-temperature hydrogen bonding is extremely strong, the proton and deuteron are located in the midpoint of the O···O segment, and their ground and first excited vibrational states are located above the barrier U0 between the local minima. The vibrational frequencies, in this case, are 1543 and 1709 cm−1 for the proton and 1045 and 1087 cm−1 for the deuteron. As the temperature rises and the barrier height increases in H-DBM, the zero-point vibrational state of the proton begins to move into one of the local minima at T > 50 K, while the excited state remains in the broad single-well potential. The same is observed in D-DBM, but with a significant temperature delay. Compounds with donor (−OCH3) and acceptor (−NO2) substituents in the phenyl ring were also synthesized and their spectra were obtained. Both results confirm existing ideas about the nature of the extremely strong hydrogen bond. The quantum-chemical calculation of the vibrational spectrum of H-DBM and D-DBM is consistent with the experimental results.
Pressure-Induced Reverse Structural Transition of Calcite at Temperatures up to 873 K and Pressures up to 19.7 GPa
Authors: Zhang Xinyu , Dai Lidong , Hu Haiying , Li Chuang
Published: January 2023

In situ Raman scattering and electrical conductivity experiments have been performed to investigate the structural phase transitions of calcite during the compressed and decompressed processes in a diamond anvil cell at temperatures of 298–873 K and pressures up to 19.7 GPa. Upon compression, calcite (CaCO3-I phase) underwent three structural phase transitions from CaCO3-I to CaCO3-II phases at 1.6 GPa, from CaCO3-II to CaCO3-III phases at 2.2 GPa, and from CaCO3-III to CaCO3-VI phases at 16.8 GPa under room temperature conditions, which were evidenced by the evolution of Raman peaks, as well as the discontinuities in the pressure-dependent Raman shifts and electrical conductivity. Upon decompression, the structural phase transitions from CaCO3-VI to CaCO3-III to CaCO3-II to CaCO3-I phases took place at the respective pressures of 5.4, 1.5, and 0.4 GPa, indicating the reversibility of calcite. Furthermore, an obvious ~11 GPa of pressure hysteresis was detected in the CaCO3-VI to CaCO3-III phase transition, whereas other reverse phase transition pressures were very close to those of compressed results. At three given representative pressure conditions (i.e., 10.5, 12.5, and 13.8 GPa), a series of electrical conductivity experiments were performed at temperature ranges of 323–873 K to explore the temperature-dependent relation of CaCO3-III to CaCO3-VI structural phase transition. With increasing pressure, the transition temperature between CaCO3-III and CaCO3-VI phases gradually decreases, which reveals an obviously negative temperature-pressure relation, i.e., P (GPa) = 19.219 (±1.105) − 0.011 (±0.002) T (K). Our acquired phase diagram of calcite can be employed to understand the high-pressure structural transitions and phase stability for carbonate minerals along various subducting slabs in the deep Earth’s interior.
Regional Quantitative Mineral Prospectivity Mapping of W, Sn, and Nb-Ta Based on Integrated Information in Rwanda, Central Africa
Authors: Chen Zhuo , Chen Jianping , Liu Tao , Li Yunfeng , Yin Qichun , Du Haishuang
Published: January 2023

As the need to discovers new mineral deposits and occurrences has intensified in recent years, it has become increasingly apparent that we need to map potentials via integrated information on the basis of metallogeny. Occurrences of mineralization such as tungsten (W), tin (Sn), columbium (Nb), tantalum (Ta), gold (Au), copper (Cu), lead (Pb), zinc (Zn), manganese (Mn) and monazite (Mnz) have been discovered in Rwanda. The objective of this study was to present a regional quantitative mineral prospectivity mapping (MPM) of W, Sn and Nb-Ta mineralization in Rwanda using the random forest (RF) method on the basis of open source data, such as geological maps, Bouguer gravity anomalies, magnetic anomalies, Landsat 8 images, ASTER GDEM, Globeland30, and OpenStreetMap. In addition, a newly introduced interpolation–density–delineation (IDD) process was applied to deal with the blank (masked) areas in remotely sensed mineral alteration extraction. Additionally, a k2-fold cross-validation method was also proposed to obtain more reasonable test errors. Firstly, the metallogenic regularity of W, Sn and Nb-Ta in Rwanda was summarized with the help of articles online. Secondly, original geological, geophysical, and remote sensing data were utilized to generate secondary data. Specifically, the IDD process was applied subsequent to the directed principal component analysis method (DPCA) to reconstruct the alteration anomaly map, and a relevant dataset was formed by the combination of original and secondary data. Thirdly, specific predictor layers for W, Sn and Nb-Ta were selected from relevant data via spatial correlation with known deposits, respectively, and the predictive models were established. Finally, near 26,000 squares were zoned in Rwanda, and RF was optimized and applied, the k2-fold cross-validation method was utilized to assess test errors, metallogenic belts and prospective areas for W, Sn, and Nb-Ta were delineated on the basis of total mineralization potential map and likelihoods map. Results proved that the open source data online were valid for drawing a preliminary mineralization potential map. Furthermore, it was also shown that the IDD method is suitable for the postprocessing of masked alteration anomaly maps. Belt IV-4 in the northwest and belt IV-2, IV-1 in the middle-east of Rwanda, containing a number of prospective areas, possess considerable likelihoods of deposits, and mining in Rwanda is at its dawn, with potential worth expecting.
Application of Maleic Acid–Acrylic Acid Copolymer as an Eco-Friendly Depressant for Effective Flotation Separation of Chalcopyrite and Galena
Authors: Yang Siqi , Tang Xuekun , Chen Rufeng , Fan Xun , Miao Jiancheng , Luo Xianping
Published: January 2023

Environmentally achieving the flotation separation of chalcopyrite and galena is always a difficult problem due to the similar floatability of the two minerals. To conquer the problem, maleic acid–acrylic acid copolymer (MA/AA), an eco-friendly reagent, was applied as a potential depressant for flotation separation of chalcopyrite from galena for the first time. Single-mineral flotation tests exhibit that MA/AA has a much better depression ability and selectivity than those of traditional galena depressants (Na2S and K2Cr2O7), which can inhibit the floatability of galena well but barely affects the flotation behavior of chalcopyrite in a wide pH range (7–11). A satisfying flotation separation effect of artificially mixed galena and chalcopyrite was realized by using MA/AA as a depressant. Based on a series of measurements including zeta potential, XPS, and contact angle, it appears that MA/AA was much more inclined to be chemically adsorbed on the surface of galena than that of chalcopyrite, which restrains the further adsorption of collectors on galena. In contrast, for chalcopyrite, the low adsorption of MA/AA hardly affects the further adsorption of collectors. According to these findings, MA/AA is considered to be potentially applicable as an effective and eco-friendly depressant in the industrial flotation separation of chalcopyrite and galena.
Geochemical Studies of Detrital Zircon Grains from the River Banks and Beach Placers of Coastal Odisha, India
Authors: Mohanty Samikshya , Papadopoulos Argyrios , Petrelli Maurizio , Papadopoulou Lambrini , Sengupta Debashish
Published: January 2023

Zircon grains are reasonably ubiquitous in river banks and beach placers as detrital minerals, including along the ~1700 km long Indian east coast, from Odisha state to the state of Kerala. Zircons from beach placers and river banks located along the eastern part of Odisha, India, were studied using LA-ICP-MS in order to delineate their geochemical characteristics. Hf (mean = 11270 ppm) and Y (mean = 1064 ppm) were the two most abundant trace elements found within zircon grains as compared to other trace elements. The abundance of uranium was observed to be 2–4 times larger than that of thorium. Zircon overgrowths formed in equilibrium with a partial melt and were similar to magmatic zircon in terms of the high Y, Hf and P content, steep heavy-enriched REE pattern, positive Ce anomaly and negative Eu anomaly. The average low Th/U ratio of the studied zircon grains distinguished them from the magmatic ones. The REE present in zircon grains was restricted to high-grade metamorphic events. The result of the present study would be useful for delineating the source region and the efficacy of resource potential and indigenous export.
Geochemical Anomalies of the Late Permian Coal in the Guishan Coalfield, Eastern Yunnan, China
Authors: Liu Langtao , Jin Chao , Zhang Beibei , Zhang Xiaogang , Su Jie , Zhao Ruixu , Gao Shuaipo
Published: January 2023

The coal-bearing sequences of the Late Permian in southwest China are enriched in critical elements Sc, V, Co, Ni, Cu, Zn, Nb, Ta, Zr and Hf. Ascertaining the conditions and basis for the enrichment of critical elements in this area is very important to support the critical metal demands of China. In this study, we analyzed the concentrations of elemental compositions of coal samples collected from the Late Permian Guishan coalfield in the eastern Yunnan, China. The results show that the C4-Upper coal seam of the Feilongma mine and C5 + 10 coal seam of the Shipeng mine are indeed rich in critical elements. The average concentration coefficients (CC) of transition metal elements Sc, V, Co, Ni, Cu, and Zn are 3.23 and 2.93, respectively, in the two coal seams. The average CCs of high-field-strength elements Nb, Ta, Zr, and Hf and non-variable valence chalcophile elements Ga and In are 2.21 and 2.53, respectively, in the two coal seams. The C4-Upper coal seam of the Feilongma mine can be divided into two sections based on the different ash contents, and the CCs of the critical elements in the two sections are almost equal. The main minerals in the two coal seams are kaolinite, siderite, quartz, gypsum, rozenite and marcasite. Multiple indicators of provenance show that the enrichment of critical elements in the Guishan coalfield is controlled by clastic terrigenous material. The source area of the Guishan coalfield is Kangdian Oldland in the northwest, and the main clastic materials are related with high-Ti basalts from the Emeishan Large Igneous Province.
Activation of Dolomite Flotation by Ferrous Hydroxide and Carbonate
Authors: Zhao Haiping , Niu Xiaopeng , Dong Bingxu , Jia Xianbing , Ruan Renman
Published: January 2023

The major problem with Carlin-type gold deposit flotation is that the high dolomite content in the concentrate decreases the quality of gold. Further, the activation mechanisms involved in dolomite flotation are still not fully understood. Herein, the correlation of Fe2+ conversion with xanthate adsorption and dolomite flotation was investigated to reveal the effect of dolomite embedded with pyrite. Flotation tests suggested that Fe2+ rather than Fe3+ improved the floatability of dolomite from 20% to 45%. Contact angles and thermodynamic tests indicated that the hydrophobicity of Fe2+-modified dolomite corresponds to the adsorption of xanthate. Importantly, time-of-flight secondary ion mass spectroscopy (Tof-SIMS) and x-ray photoelectron spectroscopy (XPS) attributed the activation of dolomite flotation to the formation of Fe(OH)2 and FeCO3. The coordination model of flotation successfully elucidated the selective adsorption of xanthate between Fe(OH)2, FeCO3 and FeOOH surfaces. The density function theory (DFT) simulation calculation was performed to identify the reaction rate at the atomic level, and the density of states (DOS) was also conducted to verify the conclusions at the electronic level. This study presents important surface chemistry evidence for understanding and regulating the poor selectivity in the flotation of Carlin-type gold deposits.
Enhancement of Hydrophilicity of Nano-Pitted TiO2 Surface Using Phosphoric Acid Etching
Authors: Koppány Ferenc , Csomó Krisztián Benedek , Varmuzsa Edvárd Márton , Bognár Eszter , Pelyhe Liza , Nagy Péter , Kientzl Imre , Szabó Dániel , Weszl Miklós , Dobos Gábor , Lenk Sándor , Erdei Gábor , Kiss Gábor , Nagy Lilien , Sréter Attila , Belik Andrea Alexandra , Tóth Zsuzsanna , Vág János , Joób-Fancsaly Árpád , Németh Zsolt
Published: January 2023

Our research group developed a novel nano-pitted (NP) TiO2 surface on grade 2 titanium that showed good mechanical, osteogenic, and antibacterial properties; however, it showed weak hydrophilicity. Our objective was to develop a surface treatment method to enhance the hydrophilicity of the NP TiO2 surface without the destruction of the nano-topography. The effects of dilute and concentrated orthophosphoric (H3PO4) and nitric acids were investigated on wettability using contact angle measurement. Optical profilometry and atomic force microscopy were used for surface roughness measurement. The chemical composition of the TiO2 surface and the oxidation state of Ti was investigated using X-ray photoelectron spectroscopy. The ccH3PO4 treatment significantly increased the wettability of the NP TiO2 surfaces (30°) compared to the untreated control (88°). The quantity of the absorbed phosphorus significantly increased following ccH3PO4 treatment compared to the control and caused the oxidation state of titanium to decrease (Ti4+ → Ti3+). Owing to its simplicity and robustness the presented surface treatment method may be utilized in the industrial-scale manufacturing of titanium implants.
Design and Simulation of a Ratiometric SPR Sensor Based on a 2D van der Waals Heterojunction for Refractive Index Measurement
Authors: Zhou Jun , Yu Xiantong , Zhang Lianzhen , Liu Xuejing , Zeng Youjun , Zhang Xuedian
Published: January 2023

Surface plasmon resonance (SPR) sensors have been widely applied in many fields because of their advantages of working in real time and high sensitivity. However, because the spectrum of an SPR sensor is easily affected by the smoothness of the metal surface, this type of sensor has obvious disadvantages in the application of quantitative detection. We designed an SPR refractive index sensor for molecular detection that has the advantage of quantifiability. A ratio spectral quantitative analysis method was established based on the two coherent dips of the SPR spectrum formed by the strong coupling effect between the surface plasmon polaritons and the excitons of the J-aggregate molecule 5,6-dichloro-2–[3–[5,6-dichloro-1-ethyl-3–(4-sulfobutyl)–2-benzimidazoline subunit] propenyl]–3-ethyl-1–(4-sulfobutyl) benzimidazole hydroxide inner salt (TDBC). The introduced MoS2/graphene van der Waals heterojunction produced an effective charge transfer to the Ag film, resulting in significant electric field enhancement at the sensing interface and further improving the detection sensitivity of the sensor. The simulation results showed that for 43 nm Ag film, for example, the ratiometric SPR sensor with the Ag film structure can obtain 16.12 RIU−1 sensing sensitivity, applied to the detection of gas molecules, while the SPR sensor with single-layer graphene and three layers of MoS2 heterostructures can obtain 50.68 RIU−1 sensing sensitivity. The addition of van der Waals heterostructures can significantly improve sensing performance by 215%.
Emerging Xene-Related Nanostructures for Versatile Applications
Authors: Wang Mengke , Huang Weichun
Published: January 2023

Investigations into semiconductor nanomaterials from both an academic and industrial point of view are of great significance [...]
B-Doped g-C3N4/Black TiO2 Z-Scheme Nanocomposites for Enhanced Visible-Light-Driven Photocatalytic Performance
Authors: Wang Yuwei , Xu Kelin , Fan Liquan , Jiang Yongwang , Yue Ying , Jia Hongge
Published: January 2023

Black TiO2 with abundant oxygen vacancies (OVs)/B-doped graphitic carbon nitride (g-C3N4) Z-scheme heterojunction nanocomposites are successfully prepared by the one-pot strategy. The OVs can improve not only photogenerated carrier separation, but also the sorption and activation of antibiotic compounds (tetracycline hydrochloride, TC). The prepared heterojunction photocatalysts with a narrow bandgap of ∼2.13 eV exhibit excellent photocatalytic activity for the degradation of tetracycline hydrochloride (65%) under visible light irradiation within 30 min, which is several times higher than that of the pristine one. The outstanding photocatalytic property can be ascribed to abundant OVs and B element-dope reducing the bandgap and extending the photo-response to the visible light region, the Z-scheme formation of heterojunctions preventing the recombination of photogenerated electrons and holes, and promoting their effective separation.
Toward Smart Biomimetic Apatite-Based Bone Scaffolds with Spatially Controlled Ion Substitutions
Authors: Cianflone Edoardo , Brouillet Fabien , Grossin David , Soulié Jérémy , Josse Claudie , Vig Sanjana , Fernandes Maria Helena , Tenailleau Christophe , Duployer Benjamin , Thouron Carole , Drouet Christophe
Published: January 2023

Biomimetic apatites exhibit a high reactivity allowing ion substitutions to modulate their in vivo response. We developed a novel approach combining several bioactive ions in a spatially controlled way in view of subsequent releases to address the sequence of events occurring after implantation, including potential microorganisms’ colonization. Innovative micron-sized core-shell particles were designed with an external shell enriched with an antibacterial ion and an internal core substituted with a pro-angiogenic or osteogenic ion. After developing the proof of concept, two ions were particularly considered, Ag+ in the outer shell and Cu2+ in the inner core. In vitro evaluations confirmed the cytocompatibility through Ag-/Cu-substituting and the antibacterial properties provided by Ag+. Then, these multifunctional “smart” particles were embedded in a polymeric matrix by freeze-casting to prepare 3D porous scaffolds for bone engineering. This approach envisions the development of a new generation of scaffolds with tailored sequential properties for optimal bone regeneration.
Modulating the Surface Properties of Lithium Niobate Nanoparticles by Multifunctional Coatings Using Water-in-Oil Microemulsions
Authors: Gheata Adrian , Spada Alessandra , Wittwer Manon , Dhouib Ameni , Molina Emilie , Mugnier Yannick , Gerber-Lemaire Sandrine
Published: January 2023

Inorganic nanoparticles (NPs) have emerged as promising tools in biomedical applications, owing to their inherent physicochemical properties and their ease of functionalization. In all potential applications, the surface functionalization strategy is a key step to ensure that NPs are able to overcome the barriers encountered in physiological media, while introducing specific reactive moieties to enable post-functionalization. Silanization appears as a versatile NP-coating strategy, due to the biocompatibility and stability of silica, thus justifying the need for robust and well controlled silanization protocols. Herein, we describe a procedure for the silica coating of harmonic metal oxide NPs (LiNbO3, LNO) using a water-in-oil microemulsion (W/O ME) approach. Through optimized ME conditions, the silanization of LNO NPs was achieved by the condensation of silica precursors (TEOS, APTES derivatives) on the oxide surface, resulting in the formation of coated NPs displaying carboxyl (LNO@COOH) or azide (LNO@N3) reactive moieties. LNO@COOH NPs were further conjugated to an unnatural azido-containing small peptide to obtain silica-coated LNO NPs (LNO@Talys), displaying both azide and carboxyl moieties, which are well suited for biomedical applications due to the orthogonality of their surface functional groups, their colloidal stability in aqueous medium, and their anti-fouling properties.
A New Electrochemical Sensor for the Detection of Ketoconazole Using Carbon Paste Electrode Modified with Sheaf-like Ce-BTC MOF Nanostructure and Ionic Liquid
Authors: Tajik Somayeh , Sharifi Fatemeh , Aflatoonian Behnaz , Di Bartolomeo Antonio
Published: January 2023

An ultrasensitive and selective voltammetric sensor with an ultratrace-level detection limit is introduced for ketoconazole (KTC) determination in real samples using a modified carbon paste electrode with a sheaf-like Ce-BTC MOF nanostructure and ionic liquid. The as-synthesized nanostructure was characterized by several techniques, including energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and field emission scanning electron microscopy (FE-SEM). The electrocatalytic performance of the developed electrode was observed by cyclic voltammetry (CV), differential pulse voltammetry (DPV), linear sweep voltammetry (LSV), and chronoamperometry. The limit of detection (LOD) of the developed sensor for KTC is 0.04 μM, and the response was found to be in the dynamic concentration range of 0.1–110.0 μM in a phosphate buffer solution. The proposed electrode exhibits acceptable electrocatalytic activity for KTC oxidation with a high sensitivity of 0.1342 μA·μM−1. The ability of the fabricated sensor to monitor KTC in real aqueous samples is demonstrated using standard addition data.
Nanomaterials for Molecular Detection and Analysis of Extracellular Vesicles
Authors: Taylor Mitchell , Giacalone Anthony , Amrhein Kristopher , Wilson Raymond , Wang Yongmei , Huang Xiaohua
Published: January 2023

Extracellular vesicles (EVs) have emerged as a novel resource of biomarkers for cancer and certain other diseases. Probing EVs in body fluids has become of major interest in the past decade in the development of a new-generation liquid biopsy for cancer diagnosis and monitoring. However, sensitive and specific molecular detection and analysis are challenging, due to the small size of EVs, low amount of antigens on individual EVs, and the complex biofluid matrix. Nanomaterials have been widely used in the technological development of protein and nucleic acid-based EV detection and analysis, owing to the unique structure and functional properties of materials at the nanometer scale. In this review, we summarize various nanomaterial-based analytical technologies for molecular EV detection and analysis. We discuss these technologies based on the major types of nanomaterials, including plasmonic, fluorescent, magnetic, organic, carbon-based, and certain other nanostructures. For each type of nanomaterial, functional properties are briefly described, followed by the applications of the nanomaterials for EV biomarker detection, profiling, and analysis in terms of detection mechanisms.
Surface Ligand Influences the Cu Nanoclusters as a Dual Sensing Optical Probe for Localized pH Environment and Fluoride Ion
Authors: Busi Kumar Babu , Das Subhalaxmi , Palanivel Mathangi , Ghosh Krishna Kanta , Gulyás Balázs , Padmanabhan Parasuraman , Chakrabortty Sabyasachi
Published: January 2023

Functional metal nanomaterials, especially in the nanocluster (NC) size regime, with strong fluorescence, aqueous colloidal stability, and low toxicity, necessitate their application potential in biology and environmental science. Here, we successfully report a simple cost-effective method for red-/green-color-emitting protein/amino-acid-mediated Cu NCs in an aqueous medium. As-synthesized Cu NCs were characterized through UV-Vis absorption spectroscopy, fluorescence spectroscopy, time-resolved photoluminescence, dynamic light scattering, zeta potential, transmission electron microscopy and X-ray photoelectron spectroscopy. The optical properties of both Cu NCs responded linearly to the variation in pH in the neutral and alkaline ranges, and a robust pH reversible nature (between pH 7 and 11) was observed that could be extended to rapid, localized pH sensor development. However, a contrasting pH response nature between protein–Cu NCs and amino acid–Cu NCs was recorded. The alteration in protein secondary structure and strong binding nature of the surfactants were suggested to explain this behavior. Furthermore, we investigated their use as an efficient optical probe for fluoride ion detection. The limit of detection for protein–Cu NCs is 6.74 µM, whereas the limit of detection for amino acid–Cu NCs is 4.67 µM. Thus, it is anticipated that ultrasmall Cu NCs will exhibit promise in biological and environmental sensing applications.
Light-Transmitting Lithium Aluminosilicate Glass-Ceramics with Excellent Mechanical Properties Based on Cluster Model Design
Authors: Li Minghan , Dong Chuang , Ma Yanping , Jiang Hong
Published: January 2023

In this study, for the first time, a cluster-plus-glue-atom model was used to optimize the composition of lithium aluminosilicate glass-ceramics. Basic glass in glass-ceramics was considered to be a 16-unit combination of three-valence {M2O3} and one-valence {Li2O} units. By adjusting the ratio of {M2O3} and {Li2O}, the composition of basic glass could be optimized. After optimization, the average cation valence of the base glass was increased to 2.875. After heat treatment of the optimized base glass, it is found that the crystal size, proportion, and crystallinity changed obviously compared with that before optimization. The main crystalline phases of all the lithium aluminosilicate glass-ceramics prepared in this work were Li2Si2O5 and LiAlSi4O10. All optimized glass-ceramics had an obvious improvement in the crystallinity, with one of the largest having a crystallinity of over 90%. Furthermore, its bending strength was 159 MPa, the microhardness was 967 Hv, and the visible light transmission rate exceeded 90%. Compared with the widely used touch panel cover glass, the optical properties were close, and the mechanical properties were greatly improved. Due to its excellent performance, it could be used in microelectronics, aerospace, deep-sea exploration, and other fields.
Study on the Simulation of Biosensors Based on Stacked Source Trench Gate TFET
Authors: Chong Chen , Liu Hongxia , Du Shougang , Wang Shulong , Zhang Hao
Published: January 2023

In order to detect biomolecules, a biosensor based on a dielectric-modulated stacked source trench gate tunnel field effect transistor (DM-SSTGTFET) is proposed. The stacked source structure can simultaneously make the on-state current higher and the off-state current lower. The trench gate structure will increase the tunneling area and tunneling probability. Technology computer-aided design (TCAD) is used for the sensitivity study of the proposed structured biosensor. The results show that the current sensitivity of the DM-SSTGTFET biosensor can be as high as 108, the threshold voltage sensitivity can reach 0.46 V and the subthreshold swing sensitivity can reach 0.8. As a result of its high sensitivity and low power consumption, the proposed biosensor has highly promising prospects.
A Core-Shell MWCNT-Pt Nanowire Electron Source with Anomalously Long-Term Stable Field Emission
Authors: Zhang Wenqi , Chao Peidong , Chen Donglei , Yang Zhan , Dong Lixin
Published: January 2023

A hybrid core-shell structured nanowire is proposed for a long-term stable electron source based on an isolated platinum/multi-walled carbon nanotube (Pt/MWCNT). This hybrid nanowire is prepared by growing a Pt shell on a metallic MWCNT through a field-emission-induced deposition (FEID) method. An in situ field emission (FE) platform was constructed inside a scanning electron microscope (SEM) equipped with two nanorobotic manipulators (NRMs) for the preparation and testing of the hybrid nanowire. An in situ fatigue test was conducted with high current intensity (500 nA) to show the influence of the Pt shell. Compared with the pristine bare MWCNT, our hybrid-nanowire-based electron source has a lifetime of hundreds of times longer and can work continuously for up to 48 h under relatively high pressure (3.6×10-3 Pa) without having an apparent change in its structure or emission currents, demonstrating good stability and tolerance to poor working conditions. The anomalous long-term stability is attributed mainly to the shielding of oxygen by Pt from the carbon shells and less heating due to the work function lowering by Pt.
Enhancing Photoluminescence of CsPb(ClxBr1−x)3 Perovskite Nanocrystals by Fe2+ Doping
Authors: Wu Chang , Li Yan , Xia Zhengyao , Ji Cheng , Tang Yuqian , Zhang Jinlei , Ma Chunlan , Gao Ju
Published: January 2023

The doping of impurity ions into perovskite lattices has been scrupulously developed as a promising method to stabilize the crystallographic structure and modulate the optoelectronic properties. However, the photoluminescence (PL) of Fe2+-doped mixed halide perovskite NCs is still relatively unexplored. In this work, the Fe2+-doped CsPb(ClxBr1−x)3 nanocrystals (NCs) are prepared by a hot injection method. In addition, their optical absorption, photoluminescence (PL), PL lifetimes, and photostabilities are compared with those of undoped CsPb(Br1−xClx)3 NCs. We find the Fe2+ doping results in the redshift of the absorption edge and PL. Moreover, the full width at half maximums (FWHMs) are decreased, PL quantum yields (QYs) are improved, and PL lifetimes are extended, suggesting the defect density is reduced by the Fe2+ doping. Moreover, the photostability is significantly improved after the Fe2+ doping. Therefore, this work reveals that Fe2+ doping is a very promising approach to modulate the optical properties of mixed halide perovskite NCs.