bluuebunny/crossref_metadata_2025 huggingface dataset:
Medicine and the Law
Authors: McQuoid-Mason D J
Published: August 2022

The case involving Dr Tim De Maayer in Gauteng Province, South Africa (SA), raises the question whether there is a legal and ethical duty on public sector doctors whose complaints to hospital administrators have been ignored, to inform the public about harm to child patients due to intentional maladministration, negligence or indifference by the local and provincial authorities. An analysis of the SA Constitution, the National Health Act No. 61 of 2003, the Children’s Act No. 38 of 2005, the Health Professions Act No. 56 of 1974 and the Rules and Guidelines of the Health Professions Council of South Africa (HPCSA) established in terms of the Health Professions Act indicates that Dr De Maayer acted both legally and ethically to protect the child patients at Rahima Moosa Hospital. As the complaints of harm caused to the patients because of conditions in the hospital were raised three times with the official functionaries concerned, and ignored by them, he was fully justified to try other measures to protect the patients. It seems that he hoped that by bringing the conditions at the hospital to the attention of the media, the public reaction would be such as to pressurise the administrators to redress the situation. The irony is that the officials who sought to discipline him were themselves guilty of violating the Constitution, the National Health Act and the Children’s Act, and should be disciplined. Furthermore, if they are registered with the HPCSA, they should be reported and disciplined for violating the HPCSA’s Ethical Rules of Conduct and its Ethical Guidelines on good practice.
Glutamine metabolism modulates chondrocyte inflammatory response
Authors: Arra Manoj , Swarnkar Gaurav , Adapala Naga Suresh , Naqvi Syeda Kanwal , Cai Lei , Farooq Rai Muhammad , Singamaneni Srikanth , Mbalaviele Gabriel , Brophy Robert , Abu-Amer Yousef
Published: August 2022

Osteoarthritis is the most common joint disease in the world with significant societal consequences but lacks effective disease-modifying interventions. The pathophysiology consists of a prominent inflammatory component that can be targeted to prevent cartilage degradation and structural defects. Intracellular metabolism has emerged as a culprit of the inflammatory response in chondrocytes, with both processes co-regulating each other. The role of glutamine metabolism in chondrocytes, especially in the context of inflammation, lacks a thorough understanding and is the focus of this work. We display that mouse chondrocytes utilize glutamine for energy production and anabolic processes. Furthermore, we show that glutamine deprivation itself causes metabolic reprogramming and decreases the inflammatory response of chondrocytes through inhibition of NF-κB activity. Finally, we display that glutamine deprivation promotes autophagy and that ammonia is an inhibitor of autophagy. Overall, we identify a relationship between glutamine metabolism and inflammatory signaling and display the need for increased study of chondrocyte metabolic systems.
Mobile phone enabled mental health monitoring to enhance diagnosis for severity assessment of behaviours: a review
Authors: Gopalakrishnan Abinaya , Venkataraman Revathi , Gururajan Raj , Zhou Xujuan , Genrich Rohan
Published: August 2022

Mental health issues are a serious consequence of the COVID-19 pandemic, influencing about 700 million people worldwide. These physiological issues need to be consistently observed on the people through non-invasive devices such as smartphones, and fitness bands in order to remove the burden of having the conciseness of continuously being monitored. On the other hand, technological improvements have enhanced the abilities and roles of conventional mobile phones from simple communication to observations and improved accessibility in terms of size and price may reflect growing familiarity with the smartphone among a vast number of consumers. As a result of continuous monitoring, together with various embedded sensors in mobile phones, raw data can be converted into useful information about the actions and behaviors of the consumers. Thus, the aim of this comprehensive work concentrates on the literature work done so far in the prediction of mental health issues via passive monitoring data from smartphones. This study also explores the way users interact with such self-monitoring technologies and what challenges they might face. We searched several electronic databases (PubMed, IEEE Xplore, ACM Digital Libraries, Soups, APA PsycInfo, and Mendeley Data) for published studies that are relevant to focus on the topic and English language proficiency from January 2015 to December 2020. We identified 943 articles, of which 115 articles were eligible for this scoping review based on the predetermined inclusion and exclusion criteria carried out manually. These studies provided various works regarding smartphones for health monitoring such as Physical activity (26.0 percent; 30/115), Mental health analysis (27.8 percent; 32/115), Student specific monitoring (15.6 percent; 18/115) are the three analyses carried out predominantly.
Privacy-preserving household load forecasting based on non-intrusive load monitoring: A federated deep learning approach
Authors: Zhou Xinxin , Feng Jingru , Wang Jian , Pan Jianhong
Published: August 2022

Load forecasting is very essential in the analysis and grid planning of power systems. For this reason, we first propose a household load forecasting method based on federated deep learning and non-intrusive load monitoring (NILM). As far as we know, this is the first research on federated learning (FL) in household load forecasting based on NILM. In this method, the integrated power is decomposed into individual device power by non-intrusive load monitoring, and the power of individual appliances is predicted separately using a federated deep learning model. Finally, the predicted power values of individual appliances are aggregated to form the total power prediction. Specifically, by separately predicting the electrical equipment to obtain the predicted power, it avoids the error caused by the strong time dependence in the power signal of a single device. In the federated deep learning prediction model, the household owners with the power data share the parameters of the local model instead of the local power data, guaranteeing the privacy of the household user data. The case results demonstrate that the proposed approach provides a better prediction effect than the traditional methodology that directly predicts the aggregated signal as a whole. In addition, experiments in various federated learning environments are designed and implemented to validate the validity of this methodology.
Differential gene expression analysis after DAPK1 knockout in hepatocellular carcinoma cells
Authors: Li Yuanqi , Huang Hui , Yu Huajun , Mo Ting , Wei Ting , Li Guodan , Jia Yufang , Huang Xiaoqin , Tu Mingjin , Yan Xiuwen , Zhang Haitao
Published: August 2022

Background

The mechanism through which death-associated protein kinase 1 (DAPK1) causes hepatocellular carcinoma (HCC) progression remains unclear. In this study, we aimed to identify key proteins that were altered after DAPK1 knockout.

Methods

Stable DAPK1 knockout HCC cell lines were established, then the differentially expressed genes (DEGs) of HCC were screened using the NetworkAnalyst database and enriched using the Metascape software. Protein-protein interaction networks (PPIs) were analyzed and visualized using the STRING database expansion.

Results

In total, 732 differentially expressed genes were identified, including 415 upregulated genes and 317 downregulated genes. Through Cytoscape software scoring, 10 pivotal genes were found to be closely related to changes in DAPK1 expression; Kininogen-1 (KNG1), Complement C3 (C3), Metalloproteinase inhibitor 1 (TIMP1), and Alpha-2-HS-glycoprotein (AHSG) were the most strongly associated with DAPK1 expression changes. Moreover, western blot analysis results revealed that changes in the levels of proteins encoded by the four key genes after DAPK1 knockout were consistent with those seen in the database screening.

Conclusions

These results provide a direction for further studies on the DAPK1 gene and on the mechanism through which DAPK1 leads to hepatocellular carcinoma development.
A Quantitative Analysis of the Fire Hazard Generated from Hydrogen Fuel Cell Electric Vehicles
Authors: Kang Sungwook , Lee Kyu Min , Kwon MinJae , Lim Ohk Kun , Choi Joung Yoon
Published: August 2022

There is a lack of information on (i) the potential fire load of new green-technology vehicles, (ii) flame spread behavior, (iii) thermal impacts on high-pressure hydrogen storage vessels (HSVs) and lithium-ion batteries (LIBs) during fuel cell electric vehicles fires (FCEVs), and (iv) thermal damage to adjacent vehicles and upper structural members during FCEV fires occurring in civil structures, such as underground spaces, multi-story parks, and tunnels. In view of this, a full-scale fire test was conducted in this study to quantitatively assess the fire risk of hydrogen FCEVs. Large-scale cone calorimetry was used to quantify the thermal intensity released from the FCEV fire. The flame spreading behavior through an FCEV with HSVs and LIBs was observed using the thermocouples installed. Changes in the temperature and irradiance around the FCEV fire were also measured using an instrumented test rig. The peak heat release rate, total heat released, and fire growth rate were observed to be 5.99 MW, 11.8 GJ, and 0.0055 kW/s², respectively. The temporal point of hydrogen gas release from the HSVs' thermal pressure relief device (TPRD) was estimated to be 16.2-26.2 min. The initiation of thermal runaway of LIBs was deduced from the temperature-time profiles of the LIB modules and their metal housing approximately 22.2 min after HCEV ignition. Moreover, FCEV fires could thermally impair adjacent upper structural members by 800 ℃ combustion gas for at least 13 min and emit a median heat flux of 27.2 kW/m² (peak heat flux of 76.5 kW/m²) to adjacent vehicles. The measurements and findings obtained from this study can contribute to the evaluation of and further studies on newly emerging fire hazards.
Estudo bibliométrico da produção científica internacional sobre empreendedorismo digital
Authors: Rayane Silva Bezerra Paloma , Maria Araújo de Souza Sandra , Da Costa Gonçalves Geuda A.
Published: August 2022

O objetivo desta pesquisa foi mapear a produção científica internacional sobre empreendedorismo digital. Para alcançar esse propósito, foi conduzida uma pesquisa do tipo exploratória, descritiva e bibliométrica, com abordagem quantitativa. A mensuração da produção científica foi baseada nas três leis clássicas da bibliometria: Lei de Bradford, Lei de Zipf e Lei de Lotka. O estudo seguiu as etapas definidas por Sousa, Fontenele, Silva e Filho (2019) para a condução de pesquisas bibliométricas, a saber: seleção da base de dados e do software bibliométrico, definição da amostra, levantamento da amostra, tabulação e tratamento de dados descritivos, e análise dos dados. Os dados foram coletados do banco de dados da Web Of Science e tabulados no software Excel. Para analisar as redes bibliométricas de coocorrência de palavras-chave e de citação (autores e periódicos) utilizou-se o software VOS Viewer. Este estudo mostra de forma geral as principais correntes temáticas exploradas em cenário internacional sobre o empreendedorismo digital: Transformação Digital, Estratégia, Data Science e Inovação Digital. Também sinaliza outros aspectos relacionados ao construto, oferecendo um respaldo teórico para outras pesquisas, sobretudo para ampliar o campo do conhecimento sobre o assunto analisado.
Role of Lipoprotein Associated Phospholipase A2 in Diagnosis of Coronary Artery Disease
Authors: Veena V , Ganesh M , Silambanan Santhi
Published: August 2022

Introduction: Cardiovascular Diseases (CVD) are a major cause of significant morbidity and mortality in industrialized countries, of which Coronary Artery Disease (CAD) is the commonest. The diagnostic workup of CAD has improved over the years starting from conventional investigations like ECG to invasive procedures like coronary angiogram. Moving forward, numerous novel inflammatory biomarkers are coming up to diagnose CAD. Aim: To assess the role of Lipoprotein associated Phospholipase A2 (LpPLA2) as an independent predictor of CAD. Materials and Methods: This case-control study was conducted in the Inpatient Department of Cardiology at Sri Ramachandra Medical College and Research Institute, Chennai, Tamil Nadu, India, from September 2014 to November 2014. Participants without significant blockage in the coronary arteries and without detectable atheroma served as controls and those with detectable atheroma and significant blockage in coronary arteries served as cases. Peripheral blood samples of 80 male patients aged over 40 years undergoing Coronary Angiography were processed for LpPLA2 levels. Mean and Standard deviation were calculated for the parameters included in the study. All statistical analyses were performed using Statistical Package for Social Sciences (SPSS) version 15.0. Results: Mean age of the participants in the controls group was 51.75±8.74 years and that of the cases group was 59.15±11.31 years. The mean LpPLA2 level in the cases was found to be higher than that in the controls and the difference was statistically significant (p-value <0.05). No correlation was noted between the age and BMI of both the groups with their respective LpPLA2 levels. Conclusion: The current study showed that LpPLA2 can be used as a potential independent predictor of CAD, thus minimising the usage of invasive investigations and favouring the psychosocial and economic welfare of the patients.
Influence of Nutrient and Weed Management on Growth, Yield and Energetics of Maize
Authors: Gummadi Sasi Chandra , Kumari Gayatri
Published: August 2022

A field experiment entitled “Influence of nutrient and weed management on growth, yield and bioenergetics of maize (Zea mays L.)” was conducted in agricultural research farm of Lovely Professional University, Punjab. The investigation was laid out in factorial randomized block design with three replications, aimed to study the impact of nutrient and weed management on growth attributes, yield attributes and bioenergetics of maize. The treatment consisted of three nutrient management treatments viz., T1 (100% N through Recommended dose of fertilizer), T2 (75% N through RDF and 25% N through vermicompost (P and K recommended doses)), T3 (75% N through RDF and 25% N through Farmyard manure) (recommended doses of P and K)); three weed management treatments, viz, W1 (control), W2 (Atrazine @1 kg a.i/ha + Tembotrione @110 g a.i/ha), W3 (Live mulching with cowpea). The results of the experiment revealed that among the nutrient management treatments, significantly higher growth attributes, yield attributes, energy output, energy efficiency index was observed with treatment T2 (75% N through RDF and 25% N through vermicompost) and the lowest was observed in treatment T1 (100% N through RDF), the pooled data suggested that yield was significantly highest in treatment combination T2W2 (75% N through RDF and 25% N through vermicompost along with Atrazine @1 kg a.i/ha + Tembotrione @110 g a.i/ha).
Enhanced Performance of Ternary CuGaSe2 Thin‐Film Photovoltaic Solar Cells and Photoelectrochemical Water Splitting Hydrogen Evolution with Modified p–n Heterointerfaces
Authors: Ishizuka Shogo , Okamoto Riku , Ikeda Shigeru
Published: August 2022

Renewable energy sources, in particular, photovoltaic solar cells and hydrogen fuel, are expected to be the pillars of a sustainable society. Chalcopyrite CuGaSe2 (CGSe) has potential for using in such applications. This article presents efficient solar cells suitable as top cells for tandem devices and highly active photocathodes for solar hydrogen evolution using CGSe photoabsorber layers with modified p–n heterointerfaces. Rb‐doping during the last stage of CGSe film growth effectively improves the photovoltaic performance, and solar cell efficiency of >10% with a high fill factor (FF) of 74.6% is obtained. The half‐cell solar‐to‐hydrogen conversion efficiency reaches 8% with the use of a photocathode composed of a CGSe film grown in an identical growth batch. Interface modification with i) a Cu‐deficient layer, ii) alkali‐metal doping, and iii) an n‐type buffer layer formed on the CGSe film surface is found to a be key to control the energy conversion device parameters, such as the FF and open circuit voltage of solar cells and the onset potential of photoelectrochemical cells, due to the suppression of interface recombination.
When Poor Light‐Emitting Spiro Compounds in Solution Turn into Emissive Pure Layers in Organic Light‐Emitting Diodes: The Key Role of Phosphine Substituents
Authors: Tourneur Pauline , Lucas Fabien , Brouillac Clément , Quinton Cassandre , Lazzaroni Roberto , Olivier Yoann , Viville Pascal , Poriel Cyril , Cornil Jérôme
Published: August 2022

Spiro compounds are widely used as host matrices in organic light‐emitting diodes (OLEDs). Here, inspired by the recent developments in thermally activated delayed fluorescence (TADF) materials, the potential as a light emitter of two spiro‐configured organic semi‐conductors is investigated, constructed by the association of quinolinophenothiazine (QPTZ) or indoloacridine (IA) as the electron‐rich fragment and diphenylphosphine oxide fluorene as the electron‐poor fragment. By comparison with structural analogues lacking phosphine oxides, the crucial role played by these electron‐accepting substituents not only on the photo‐physical properties but also on the device performances is evidenced. Despite a very low quantum yield in solution, these two compounds unexpectedly display good emission properties when incorporated as a pure layer in OLEDs, thus highlighting the role of intermolecular effects.
Nanoscopy of Aluminum Plasmonic Cavities by Cathodoluminescence and Second Harmonic Generation
Authors: Zar Tchiya , Ron Racheli , Shavit Omer , Krause Alon , Gachet David , Salomon Adi
Published: August 2022

Herein, centrosymmetric aluminum plasmonic structures composed of triangular cavities are studied and their long‐range coupling by cathodoluminescence nanoscopy are visualized. Four different plasmonic structures containing the same subunit are studied. The plasmonic modes of the individual triangular subunits are localized at the triangle sides rather than at the vertices, in agreement with other studies. Yet, upon strong interaction between the cavities, a redistribution of the electromagnetic field is observed such that it delocalizes around the cavities in the form of a contour, providing a mode enhancement and a pronounced nonlinear response as observed by second harmonic generation. Comparison between plasmonic structures made of either silver or aluminum reveals that the metal dielectric function plays an important role in the interaction between the cavities. This work provides a rationale for designing plasmonic structures with enhanced nonlinear activity.
Engineering the Dispersion of Surface Plasmon Polariton/Epsilon‐Near‐Zero Modes through Modal Separation and Optical Confinement
Authors: Nolen J. Ryan , Cleri Angela , Kelley Kyle , Runnerstrom Evan L. , Nordlander Josh , Folland Thomas G. , Maria Jon-Paul , Caldwell Joshua D.
Published: August 2022

Doped cadmium oxide (CdO) films support tunable, low‐loss surface plasmon polaritons (SPPs) and epsilon‐near‐zero (ENZ) modes throughout the mid‐infrared. Prior work demonstrated that polaritonic strong coupling could be realized in bilayer films of CdO supporting adjacent SPP and ENZ modes. The hybridized SPP‐ENZ dispersion displays a prominent anti‐crossing with an amplitude dependent on the spectral and spatial overlap of the modes. Here, we leverage the low carrier diffusivity, in concert with the broad tunability of the plasma frequency in CdO to control the SPP‐ENZ dispersion within monolithic, multilayer CdO structures featuring dielectric, unintentionally doped CdO coatings or spacer layers. In the case of the former, the coating induces further compression of the polaritonic fields, altering the dielectric environment. In contrast, when incorporated as a spacer layer, the spatial overlap of the constituent polaritonic near‐fields is reduced. In all cases, the anti‐crossing behavior of the hybrid SPP‐ENZ modes is maintained, thus inheriting the extreme light confinement of the ENZ mode and extended propagation length of the SPPs. Through simultaneous control over the SPP‐ENZ coupling strength and group velocities, significant tunability over the SPP‐ENZ dispersion is demonstrated, enabling applications such as in‐plane waveguiding, tailored thermal emission, and tunable near‐field heat transfer.
Design for Highly Efficient Nanometagratings and Theory of Extreme Subdiffraction Photon Control
Authors: Gao Yan-ming , Yu Xiang-yang
Published: August 2022

Conventional planar metasurfaces are always much larger than the wavelength level. Previous studies on extreme wavefront control based on superoscillation suggest a fundamental tradeoff between the size and efficiency of diffraction‐based metasurfaces. Herein, the theory of extreme subdiffraction photon control is proposed and the abnormal wave propagation phenomenon supporting logical design for highly efficient metasurfaces of subwavelength size is pointed out. A new class of novel metasurfaces named nanometagratings is demostrated, which is smaller than one wavelength, and manages to achieve arbitrary wavefront engineering with high conversion efficiency, enabling extreme photon control within subwavelength scale. The theoretical approach is expected to open the avenue for ultrasmall highly efficient functional metasurfaces and promises novel applications such as highly integrated on‐chip quantum optical information computation.
Intensity Correlations in Quantum Cascade Laser Harmonic Frequency Combs
Authors: Gabbrielli Tecla , Bruno Natalia , Corrias Nicola , Borri Simone , Consolino Luigi , Bertrand Mathieu , Shahmohammadi Mehran , Franckié Martin , Beck Mattias , Faist Jérôme , Zavatta Alessandro , Cappelli Francesco , De Natale Paolo
Published: August 2022

A novel study on harmonic frequency combs emitted by quantum cascade lasers (QCLs) is presented here, demonstrating the presence of intensity correlations between twin modes characterizing the emission spectra. These originate from a four‐wave mixing process driven by the active medium's third‐order nonlinearity. The study of such correlations is essential for the engineering of a new generation of semiconductor devices with the potential of becoming integrated emitters of light with quantum properties, such as squeezing and entanglement. Starting from experimental results, the limits of state‐of‐the‐art technology are discussed as well as the possible methodologies that could lead to the detection of nonclassical phenomena, or alternatively improve the design of QCLs, in the compelling perspective of generating quantum correlations in mid‐infrared light.
Hydrodynamics and mass transfer enhancement of gas–liquid flow in micropacked bed reactors: Effect of contact angle
Authors: Wang Hongbin , Zhou Tao , Han Shaopeng , Duan Lian , Sang Le , Zhao Zhiping
Published: August 2022

Pressure drop, residence time distribution, dispersive behavior, liquid holdup, and mass transfer performance of gas–liquid flow in micropacked bed reactors (μPBRs) with different contact angles (CA) of particles are studied. The value of pressure drop for three types of beads can be obtained: copper beads (CA = 88.1°) > stainless steel beads (CA = 70.2°) > glass beads (CA = 47.1°). The liquid axial dispersion coefficient is 1.58 × 10−6 to 1.07 × 10−5 m2/s for glass beads and copper beads, which is smaller than those of trickle bed reactors. The liquid holdup of 400 μm copper beads is larger than that of 400 μm glass beads. The ratio of effective interfacial area enhancement is evaluated up to 55% for big contact angle beads compared with the hydrophilic glass beads. In addition, correlations of pressure drop, liquid holdup, and effective interfacial area in μPBRs with different wettability beads are developed and predicted values are in agreement with the experimental data.
Oxalate Oxidase for In Situ H2O2‐Generation in Unspecific Peroxygenase‐Catalysed Drug Oxyfunctionalisations**
Authors: Romero Elvira , Johansson Magnus J. , Cartwright Jared , Grogan Gideon , Hayes Martin A.
Published: August 2022

H2O2‐driven enzymes are of great interest for industrial biotransformations. Herein, we show for the first time that oxalate oxidase (OXO) is an efficient in situ source of H2O2 for one of these biocatalysts, which is known as unspecific peroxygenase (UPO). OXO is reasonably robust, produces only CO2 as a by‐product and uses oxalate as a cheap sacrificial electron donor. UPO has significant potential as an industrial catalyst for selective C−H oxyfunctionalisations, as we confirm herein by testing a diverse drug panel using miniaturised high‐throughput assays and mass spectrometry. 33 out of 64 drugs were converted in 5 μL‐scale reactions by the UPO with OXO (conversion >70 % for 11 drugs). Furthermore, oxidation of the drug tolmetin was achieved on a 50 mg scale (TONUPO 25 664) with 84 % yield, which was further improved via enzyme immobilization. This one‐pot approach ensures adequate H2O2 levels, enabling rapid access to industrially relevant molecules that are difficult to obtain by other routes.
Diastereo‐ and Enantioselective Construction of Vicinal All‐Carbon Quaternary Stereocenters via Iridium/Europium Bimetallic Catalysis
Authors: Wang Wei , Zhang Fangqing , Liu Yangbin , Feng Xiaoming
Published: August 2022

The diastereo‐ and enantioselective construction of vicinal all‐carbon quaternary stereocenters is a formidable task. We here report a synergistic bimetallic catalysis via a chiralN,N′‐dioxide‐europium (Eu) complex and a phosphoramidite‐iridium (Ir) catalyst for the asymmetric allylation of oxindole derivatives by using challenging trisubstituted allylic esters. The allylated products bearing vicinal all‐carbon quaternary stereocenters were obtained with good diastereoselectivities (up to 20 : 1 dr) and excellent enantioselectivities (up to 99 % ee). Control experiments showed that the complementary diastereomers of the products were not accessible by the change of the stereochemistry of the chiralN,N′‐dioxide ligand.
Cobalt/Salox‐Catalyzed Enantioselective Dehydrogenative C−H Alkoxylation and Amination
Authors: Chen Jia‐Hao , Teng Ming‐Ya , Huang Fan‐Rui , Song Hong , Wang Zhen‐Kai , Zhuang He‐Lin , Wu Yong‐Jie , Wu Xu , Yao Qi‐Jun , Shi Bing‐Feng
Published: August 2022

The past decade has witnessed a rapid progress in asymmetric C−H activation. However, the enantioselective C−H alkoxylation and amination with alcohols and free amines remains elusive. Herein, we disclose the first enantioselective dehydrogenative C−H alkoxylation and amination enabled by a simple cobalt/salicyloxazoline (Salox) catalysis. The use of cheap and readily available cobalt(II) salts as catalysts and Saloxs as chiral ligands provides an efficient method to access P‐stereogenic compounds in excellent enantioselectivities (up to >99 % ee). The practicality of this protocol is demonstrated by gram‐scale preparation and further derivatizations of the resulting P‐stereogenic phosphinamides, which offering a flexible asymmetric alternative to access P‐stereogenic mono‐ and diphosphine chiral ligands. Preliminary mechanistic studies on the enantioselective C−H alkoxylation reaction suggest that a cobalt(III/IV/II) catalytic cycle might be involved.
Green and Scalable Fabrication of High‐Performance Biocatalysts Using Covalent Organic Frameworks as Enzyme Carriers
Authors: Zheng Yunlong , Zhang Sainan , Guo Jinbiao , Shi Ruixuan , Yu Jiangyue , Li Kaipeng , Li Ning , Zhang Zhenjie , Chen Yao
Published: August 2022

Enzyme immobilization is essential to the commercial viability of various critical large‐scale biocatalytic processes. However, challenges remain for the immobilization systems, such as difficulties in loading large enzymes, enzyme leaching, and limitations for large‐scale fabrication. Herein, we describe a green and scalable strategy to prepare high‐performance biocatalysts through in situ assembly of enzymes with covalent organic frameworks (COFs) under ambient conditions (aqueous solution and room temperature). The obtained biocatalysts have exceptional reusability and stability and serve as efficient biocatalysts for important industrial reactions that cannot be efficiently catalyzed by free enzymes or traditional enzyme immobilization systems. Notably, this versatile enzyme immobilization platform is applicable to various COFs and enzymes. The reactions in an aqueous solution occurred within a short timeframe (ca. 10–30 min) and could be scaled up readily (ca. 2.3 g per reaction).
Microfluidic‐assisted preparation of nano and microscale chitosan based 3D composite materials: Comparison with conventional methods
Authors: Kimna Ceren , Deger Sibel , Tamburaci Sedef , Tihminlioglu Funda
Published: August 2022

Although nanofillers contribute to improved physical characteristics and biological functionalities of polymer‐based biomaterials, their dispersion in polymer matrices is still a challenging issue in terms of obtaining consistency for the inherent properties. To tackle this problem, homogenization techniques are applied to disperse the nanofillers in such polymers, however, these methods can cause undesired changes especially in the rheological properties and the physical structure of the biopolymer matrices. Recently, as a novel homogenization technique, microfluidization has been used to homogenize polymer nanocomposites to minimize these limitations. In this study, two different nanocomposite structures as chitosan/montmorillonite (CS/MMT) and chitosan/polyhedral oligomeric silsesquioxane nanocages (CS/POSS) were homogenized with microfluidization and investigated in terms of physical alterations. Furthermore, the effect of microfluidizer technique on material characteristics was compared with conventional homogenization techniques, i.e., ultrasonic bath and sonication in terms of solution, nano – (e.g., hydrodynamic size, drug encapsulation) and macroscopic material characteristics (e.g., porosity, mechanical properties, swelling and thermal degradation). It was found that the microfluidizer homogenization improves the physical characteristics in both nano and macroscale materials: Nanospheres obtained from CS/MMT composites showed enhanced stability, uniform size distribution (<100 nm, PDI: <0.2), and good encapsulation efficiency (>50%) whereas 3D porous CS/POSS scaffolds showed improved structural uniformity (i.e., homogeneous and interconnected microstructure) and enhanced thermal and mechanical properties. The obtained results indicate that the microfluidizer homogenization ensures a successful nanofiller dispersion in polymer matrices, thereby improving the biomaterial characteristics impressively compared to the sonication methods.
Endostructural and periosteal growth of the human humerus
Authors: O'Mahoney Thomas George , Lowe Tristan , Chamberlain Andrew Timothy , Sellers William Irvin
Published: August 2022

The growth and development of long bones are of considerable interests in the fields of comparative anatomy and palaeoanthropology, as evolutionary changes and adaptations to specific physical activity patterns are expected to be revealed during bone ontogeny. Traditionally, the cross‐sectional geometry of long bones has been examined at discrete locations usually placed at set intervals or fixed percentage distances along the midline axis of the bone shaft. More recently, the technique of morphometric mapping has enabled the continuous analysis of shape variation along the shaft. Here we extend this technique to the full sequence of late fetal and postnatal development of the humeral shaft in a modern human population sample, with the aim of establishing the shape changes during growth and their relationship with the development of the arm musculature and activity patterns. A sample of modern human humeri from individuals of age ranging from 24 weeks in utero to 18 years was imaged using microtomography at multiple resolutions and custom Matlab scripts. Standard biomechanical properties, cortical thickness, surface curvature, and pseudo‐landmarks were extracted along radial vectors spaced at intervals of 1° at each 0.5% longitudinal increment measured along the shaft axis. Heat maps were also generated for cortical thickness and surface curvature. The results demonstrate that a whole bone approach to analysis of cross‐sectional geometry is more desirable where possible, as there is a continuous pattern of variation along the shaft. It is also possible to discriminate very young individuals and adolescents from other groups by relative cortical thickness, and also by periosteal surface curvature.
Metabolic profiling of soyasaponin Bb in rat plasma, urine, bile, and feces after intragastric administration
Authors: Yu Xinwei , Wu Yuchen , Wang Yuzhen , Cheng Yu , Xiang Zheng
Published: August 2022

Soyasaponin Bb is one of the bioactive oleanolic acid–type triterpenoid saponins mainly isolated from soybean. It possesses significant antithrombosis, hypolipidemic, anticancer, and antioxidant activities. However, the metabolic profiles of soyasaponin Bb are still unknown. The present study investigated the metabolites of soyasaponin Bb in plasma, bile, urine, and feces samples after intragastric administration using ultra‐performance liquid chromatography coupled with quadrupole‐time‐of‐flight‐mass spectrometry, and its possible metabolic pathways were subsequently proposed. Using the metabolite profiling strategy, 11 metabolites were first identified from urine, plasma, bile, and feces of rats after intragastric administration of soyasaponin Bb. Hydroxylation and hydrolysis were the major metabolic pathways of soyasaponin Bb in rat. The results expand our knowledge of the metabolism of soyasaponin Bb, which could provide valuable information for better comprehension of future pharmacological research.
Quantification of SHR0302 in human plasma by UPLC–MS/MS and application to a pharmacokinetic study
Authors: Ding Li‐kun , Chen Yan , Liu Mei‐you , Gao Xiao‐hua , Ren Dan‐jun , Diao Qing‐bo , Yang Lin , Wen Ai‐dong , Wang Jing‐wen
Published: August 2022

SHR0302, as a novel Janus kinase (JAK) inhibitor 1, is used for treatment of rheumatoid arthritis (RA) in humans. A novel and sensitive ultra‐high performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) has been developed and validated for determining the concentration of SHR0302 in human plasma. A precipitation deproteinization method was used for plasma pretreatment with methanol. Detection was carried out on an Agilent 1,260 UPLC coupled with a Triple Quad 4000 mass spectrometer operated in positive multiple reaction monitoring mode, and the analytes were separated on a Synergi Polar‐RP C18 (50 × 2.0 mm, 4 μm, Phenomenex) analytical column with gradient elution of 0.1% formic acid, and 2 mmol/l ammonium acetate in water and 0.1% formic acid and 2 mmol/l ammonium acetate in methanol, The selected ion transitions were m/z 415.2 → 258.2 and m/z 398.2 → 258.2 for SHR0302 and SHR143181 (internal standard), respectively. A full validation, including selectivity, linearity, carryover, precision, accuracy, recovery, matrix effect, dilution integrity and stability, was carried out in human plasma. It was successfully applied to a pharmacokinetic study in Chinese healthy subjects after oral administration of SHR0302 tablet.
Microkinetic Modeling of the Transient CO2 Methanation with DFT‐Based Uncertainties in a Berty Reactor
Authors: Kreitz Bjarne , Wehinger Gregor D. , Goldsmith C. Franklin , Turek Thomas
Published: August 2022

The transient operation of methanation reactors can become desirable when coupled with fluctuating renewable energies in Power‐to‐Gas scenarios, which requires suitable kinetic approaches that can describe the transient catalytic phenomena. A combined experimental and theoretical investigation of the transient CO2 methanation is conducted using concentration forcing to derive a suitable microkinetic model. Methanation experiments are performed with a Ni/SiO2 catalyst in a Berty‐type reactor at industrially relevant conditions. The microkinetics are based on previous work and were automatically constructed for the Ni(111) facet using the Reaction Mechanism Generator. A feasible set of energetic parameters of the microkinetic models was identified in a theory‐constrained optimization procedure within the DFT uncertainty space that can accurately reproduce the experimental results on a first‐principles basis. The microkinetic model unravels that the formation of H2O* and CH3* control the activity and selectivity of Ni(111) under the investigated conditions.
Electronic Metal‐Support Interaction Strengthened Pt/CoAl‐LDHs Catalyst for Selective Cinnamaldehyde Hydrogenation
Authors: Gao Zhexi , Cai Luoyu , Miao Chenglin , Hui Tianli , Wang Qian , Li Dianqing , Feng Junting
Published: August 2022

Cinnamaldehyde (CAL) is a typical sustainable biomass molecule which is classified as α, β‐unsaturated aldehydes. Selective hydrogenation of CAL to produce high‐value and fine chemical cinnamylalcohol (COL) is an attractive catalytic transformation process. However, the hydrogenation of C=O bond in CAL is more unfavorable than C=C bond in thermodynamics and kinetics, leading to great challenge on achieving high yield of unsaturated alcohol. In this work, a Pt/CoAl‐LDHs catalyst was prepared for hydrogenation of CAL to COL, showing outstanding intrinsic activity (TOF as high as 4.93 s−1) and finally achieving 93.6 % selectivity at 95.4 % conversion. In contrast, the yields of COL over Pt/Co(OH)2 and Pt/Al(OH)3 were only 73 % and 34 % respectively. Characterizations including Raman, O‐XAFS, XPS revealed that the Co2+−O2−−Al3+ structure in CoAl‐LDHs contributed to strengthened metal‐support interactions, and resulted in electron‐rich and geometric decoration Ptδ− sites. The electron‐rich Ptδ− provided preferable H2 activation capability, and also exposed abundant unsaturated sites which optimized the adsorption mode of cinnamaldehyde favorable for C=O hydrogenation. However, in Pt/Co(OH)2 and Pt/Al(OH)3 catalysts, the Pt0 without electron‐rich and unsaturated property cannot improve the H2 activation capability as well as electronic repellency to C=C bond. In addition, a possible catalytic mechanism was proposed to illustrate the role of Ptδ−−Co2+−O2−−Al3+ interfacial structure on enhancing activity and selectivity.
Revealing the Heterogeneity of Large‐Area MoS2Layers in the Electrocatalytic Hydrogen Evolution Reaction
Authors: Schumacher Simon , Madauß Lukas , Liebsch Yossarian , Tetteh Emmanuel Batsa , Varhade Swapnil , Schuhmann Wolfgang , Schleberger Marika , Andronescu Corina
Published: August 2022

The electrocatalytic activity concerning the hydrogen evolution reaction (HER) of micrometer‐sized MoS2layers transferred on a glassy carbon surface was evaluated by scanning electrochemical cell microscopy (SECCM) in a high‐throughput approach. Multiple areas on single or multiple MoS2layers were assessed using a hopping mode nanocapillary positioning with a hopping distance of 500 nm and a nanopipette size of around 55 nm. The locally recorded linear sweep voltammograms revealed a high lateral heterogeneity over the MoS2sheet regarding their HER activity, with currents between −40 and −60 pA recorded at −0.89 V vs. reversible hygrogen electrode over about 4400 different measured areas on the MoS2sheet. Stacked MoS2layers did not show different electrocatalytic activity than the single MoS2sheet, suggesting that the interlayer resistance influences the electrocatalytic activity less than the resistances induced by possible polymer residues or water layers formed between the transferred MoS2sheet and the glassy carbon electrode.
Fabrication of Highly Luminescent and Thermally Stable Phosphors through In‐Situ Formation of BaSO4 on Sulfur Nanodots
Authors: Guo Jiaqi , Feng Anrui , Shi Yu‐e , Wang Zhenguang
Published: August 2022

Producing high performance phosphors using abundant and non‐toxic precursors yet straightforward methods are promising but still a challenging task. Herein, highly luminescent and thermally stable phosphors were fabricated through an in situ precipitation synthesis strategy. Sulfur nanodots (S‐dots) act as the precursors for precipitation reactions and also provide the luminescent centers. Structural and optical characterization investigations suggest that S‐dots are incorporated in the matrix of BaSO4, and BaSO4 provides passivation effect for the surface ligands or traps of S‐dots. This results in the promotion of photoluminescence quantum yield from 23 % to 58 %, and the BaSO4 matrix also leads to the obvious promotion of thermal stability. These merits endow the construction of phosphor‐based light‐emitting diodes by utilizing the S‐dots@BaSO4 hybrid phosphors as a color conversion layer. These research results are significant for developing sulfur‐based luminescent materials, and also provide a solid and universal theory to produce high quality phosphors.
Asymmetric Alkylation of Cyclic Ketones with Dehydroalanine via H‐Bond‐Directing Enamine Catalysis: Straightforward Access to Enantiopure Unnatural α‐Amino Acids
Authors: Retini Michele , Bartolucci Silvia , Bartoccini Francesca , Piersanti Giovanni
Published: August 2022

The growing importance of structurally diverse and functionalized enantiomerically pure unnatural amino acids in the design of drugs, including peptides, has stimulated the development of new synthetic methods. This study reports the challenging direct asymmetric alkylation of cyclic ketones with dehydroalanine derivatives via a conjugate addition reaction for the synthesis of enantiopure ketone‐based α‐unnatural amino acids. The key to success was the design of a bifunctional primary amine‐thiourea catalyst that combines H‐bond‐directing activation and enamine catalysis. The simultaneous dual activation of the two relatively unreactive partners, confirmed by mass spectrometry studies, results in high reactivity while securing high levels of stereocontrol. A broad substrate scope is accompanied by versatile downstream chemical modifications. The mild reaction conditions and consistently excellent enantioselectivities (>95 % ee in most cases) render this protocol highly practical for the rapid construction of valuable noncanonical enantiopure α‐amino‐acid building blocks.
Branched Tertiary Amines from Aldehydes and α‐Olefins by Combined Multiphase Tandem Reactions
Authors: Strohmann Marc , Vorholt Andreas J. , Leitner Walter
Published: August 2022

This study presents the transformation of olefins to branched amines by combining a hydroformylation/aldol condensation tandem reaction with the reductive amination in a combined multiphase system that can be recycled 9 times. The products are branched amines that are precursors for surfactants. Since the multiphase hydrofomylation/aldol condensation system has already been studied, the first step was to develop the partial hydrogenation of unsaturated aldehydes together with a subsequent reductive amination. The rhodium/phosphine catalyst is immobilized in a polar polyethylene phase which separates from the product phase after the reaction. Reaction and catalyst recycling are demonstrated by the conversion of the C14‐aldehyde 2‐pentylnonenal with the dimethylamine surrogate dimethylammonium dimethylcarbamate to the corresponding tertiary amine with yields up to 88 % and an average rhodium leaching of less than 0.1 % per recycling run. Furthermore, the positive influence of a Bronsted acid and carbon monoxide on the selectivity are discussed. Finally, the two PEG based systems have been merged in one recycling approach, by using the product phase of the hydroformylation aldol condensation reaction for the reductive amination reaction. The yields are stable during a nine recycling runs and the leaching low with 0.09 % over the two recycling stages.
Bridging the Analytical Gap Between Gas Treatment and Reactor Plants in Carbon2Chem®
Authors: Hegen Oliver , Salazar Gómez Jorge Iván , Grünwald Christina , Rettke Alina , Sojka Martha , Klucken Christian , Pickenbrock Jens , Filipp Jan , Schlögl Robert , Ruland Holger
Published: August 2022

The use of purified process gases as feedstock for subsequent processes requires a detailed verification of the gas purity to ensure long lifetimes of applied catalysts. Herein, the analytical infrastructure for the measurements of the cleaned gases is presented. An overview of all sampling points for the off‐ and on‐line analysis is given. The detailed decryption of the composition of the cleaned blast furnace gas, its main components as well as its traces are presented. Thereby, over 99 % of the overall signal strength of this complex gas matrix measured with a proton transfer reaction mass spectrometer with H3O+ as reagent ion could be revealed. Furthermore, by the example of the catalyst poison H2S, the necessity of monitoring continuously the gas matrix for certain compounds was proven.
Hybrid particle swarm optimization with sequential one point flipping algorithm for feature selection
Authors: Isuwa Jeremiah , Abdullahi Mohammed , Sahabi Ali Yusuf , Abdulrahim Abdulrazaq
Published: August 2022

Scientific and technological advancements lead to the continuous generation of a large amount of data. These datasets are analyzed computationally to reveal patterns and trends. While the presence of noisy and irrelevant features or attributes in these datasets is unavoidable, they negatively impact the performance of classification techniques. Feature selection is a method to pre‐process these datasets by selecting the most informative features while concurrently improving the classification accuracy. Recently, several metaheuristic algorithms were employed in this feature selection process, including particle swarm optimization (PSO). PSO is prominent in the field of feature selection due to its simplicity and global search abilities. However, it may get stuck in local optima. To solve this problem, a new update mechanism in PSO is proposed and the PSO is hybridized with a local search method. To evaluate the performance of the proposed algorithm, benchmark datasets from the University of California in Irvine (UCI) repository were utilized, the k‐nearest neighbor as the classifier. Results show that the proposed feature selection technique outperforms other optimization algorithms on these feature selection problems.
Sustainable Valorisation and Efficient Downstream Processing of Giant Reed by High‐Pressure Carbon Dioxide Pretreatment
Authors: Di Fidio Nicola , Tozzi Federico , Martinelli Marco , Licursi Domenico , Fulignati Sara , Antonetti Claudia , Raspolli Galletti Anna Maria
Published: August 2022

This work investigated the catalytic high‐pressure CO2 pretreatment of giant reed. CO2 is a renewable resource; its use does not generate chemical wastes and it can be easily removed and recycled. The effect of the addition of low concentrations of FeCl3 (0.16 wt %) and PEG 400 (1.0 wt %) on the hemicellulose hydrolysis to xylose and xylo‐oligosaccharides (XOS) is reported for the first time. Under the optimised pretreatment conditions, the xylan conversion of 82 mol % and xylose and XOS yields of 43 and 20 mol % were achieved, respectively. The solid residues obtained from different pretreatments were used as the substrate for the enzymatic hydrolysis to give glucose. The total glucose yield achieved under the optimised two‐step process was 67.8 mol % with respect to the glucan units in the biomass. The results demonstrated that PEG‐assisted FeCl3‐catalysed scCO2 pretreatment can produce xylose‐ or XOS‐rich hydrolysates and improve the enzymatic hydrolysis of biomass.