bluuebunny/crossref_metadata_2025 huggingface dataset:
Highly Stable Carboranyl Ligated Gold Nano‐Catalysts for Regioselective Aromatic Bromination
Authors: Wang Mengyue , Zhang Shengye , Gong Yue , Zhang Wangyang , Wang Yu , Chen Yupeng , Zheng Qiang , Liu Zhipan , Tang Cen
Published: July 2024

Achieving electronic/steric control and realizing selectivity regulation in nanocatalysis remains a formidable challenge, as the dynamic nature of metal‐ligand interfaces, including dissolution (metal leaching) and structural reconstruction, poses significant obstacles. Herein, we disclose carboranyls (CBs) as unprecedented carbon‐bonded functional ligands (Eads.CB‐Au(111)=−2.90 eV) for gold nanoparticles (AuNPs), showcasing their exceptional stabilization capability that is attributed by strong Au−C bonds combined with B−H⋅⋅⋅Au interactions. The synthesized CB@AuNPs exhibit core(Aun)‐satellite(CB2Au−) structure, showing high stability towards multiple stimuli (110 °C, pH=1–12, thiol etchants). In addition, different from conventional AuNP catalysts such as triphenylphosphine (PPh3) stabilized AuNPs, dissolution of catalytically active gold species was suppressed in CB@AuNPs under the reaction conditions. Leveraging these distinct features, CB@AuNPs realized outstanding p : o selectivities in aromatic bromination. Unbiased arenes including chlorobenzene (up to >30 : 1), bromobenzene (15 : 1) and phenyl acrylate were examined using CB@AuNPs as catalysts to afford highly‐selective p‐products. Both carboranyl ligands and carboranyl derived counterions are crucial for such regioselective transformation. This work has provided valuable insights for AuNPs in realizing diverse regioselective transformations.
A Photocaged Microtubule‐Stabilising Epothilone Allows Spatiotemporal Control of Cytoskeletal Dynamics
Authors: Schmitt Carina , Mauker Philipp , Vepřek Nynke A. , Gierse Carolin , Meiring Joyce C. M. , Kuch Jürgen , Akhmanova Anna , Dehmelt Leif , Thorn‐Seshold Oliver
Published: July 2024

The cytoskeleton is essential for spatial and temporal organisation of a wide range of cellular and tissue‐level processes, such as proliferation, signalling, cargo transport, migration, morphogenesis, and neuronal development. Cytoskeleton research aims to study these processes by imaging, or by locally manipulating, the dynamics and organisation of cytoskeletal proteins with high spatiotemporal resolution: which matches the capabilities of optical methods. To date, no photoresponsive microtubule‐stabilising tool has united all the features needed for a practical high‐precision reagent: a low potency and biochemically stable non‐illuminated state; then an efficient, rapid, and clean photoresponse that generates a high potency illuminated state; plus good solubility at suitable working concentrations; and efficient synthetic access. We now present CouEpo, a photocaged epothilone microtubule‐stabilising reagent that combines these needs. Its potency increases approximately 100‐fold upon irradiation by violet/blue light to reach low‐nanomolar values, allowing efficient photocontrol of microtubule dynamics in live cells, and even the generation of cellular asymmetries in microtubule architecture and cell dynamics. CouEpo is thus a high‐performance tool compound that can support high‐precision research into many microtubule‐associated processes, from biophysics to transport, cell motility, and neuronal physiology.
Formation of a Decanuclear Organometallic Dysprosium Complex via a Radical–Radical Cross–Coupling Reaction
Authors: Bajaj Neha , Kitos Alexandros A. , Mavragani Niki , Loutsch Nathan R. , Vlaisavljevich Bess , Murugesu Muralee
Published: July 2024

Over the years, polynuclear cyclic or torus complexes have attracted increasing interest due to their unique metal topologies and properties. However, the isolation of polynuclear cyclic organometallic complexes is extremely challenging due to their inherent reactivity, which stems from the labile and reactive metal‐carbon bonds. In this study, the pyrazine ligand undergoes a radical‐radical cross‐coupling reaction leading to the formation of a decanuclear [(Cp*)20Dy10(L1)10] ⋅ 12(C7H8) (1; where L1 = anion of 2‐prop‐2‐enyl‐2H‐pyrazine; Cp* = pentamethylcyclopentadienyl) complex, where all DyIII metal centres are bridged by the anionic L1 ligand. Amongst the family of polynuclear Ln organometallic complexes bearing CpR2Lnx units (CpR = substituted cyclopentadienyl), 1 features the highest nuclearity obtained to date. In‐depth computational studies were conducted to elucidate the proposed reaction mechanism and formation of L1, while probing of the magnetic properties of 1, revealed slow magnetic relaxation upon application of a static dc field.
Preparation and properties of bio‐based flame‐retardant rigid polyurethane foams with soybean oil polyols containing phosphorus
Authors: Xu Mingyang , Wang Shuai , Liu Ningning , Xu Xinyu
Published: July 2024

Two types of bio‐based RPUFs (RPUF‐P and RPUF‐PPOA) were prepared that contained ethanol‐modified polyols (Polyol‐E) and one contained an epoxidized polyol modified with phosphoric acid (Polyol‐P), and the other contained epoxidized polyol modified with phenylphosphonic acid (Polyol‐PPOA). The cell morphologies, thermal and mechanical properties, and flame retardancy characteristics of the RPUF, RPUF‐P, and RPUF‐PPOA were studied by scanning electron microscopy (SEM), thermogravimetric analysis(TGA), compression tests, limiting oxygen index (LOI), and cone calorimetry test (CCT). The porous structures revealed that the cell sizes of both RPUF‐P and RPUF‐PPOA increased first and then decreased, and the number of pores decreased first and then increased. Furthermore, the apparent density showed a similar trend of increasing before decreasing. The compressive strengths of the RPUF‐P and RPUF‐PPOA were higher than that of the RPUF, and the compressive strength of the RPUF‐P was better than that of the RPUF‐PPOA, because the hydroxyl value of the Polyol‐P was much higher than that of the Polyol‐PPOA. The crosslinking density of the RPUF‐P prepared by the PM‐200 reaction was much higher than that of the RPUF‐PPOA. The LOI values of the RPUF‐P4 and RPUF‐PPOA4 were 21.68 and 23.10, respectively. Furthermore, the value of the peak of the heat release rate (HRR) was reduced by 40.3% compared with that of pure RPUF. The total heat release (THR), smoke produce rate (SPR), and total smoke release (TSR) decreased with increased Polyol‐P and Polyol‐PPOA addition. The flame‐retardancy residues micrographs showed that the carbon layers generated from the combustion of the RPUF‐P4 and the RPUF‐PPOA4 lacked perforated structures and exhibited better densification than the pure RPUF. Based on the analysis and discussion, the flame retardancy of RPUF‐P and RPUF‐PPOA were improved mainly through a condensed and gas phases mechanism.
Discovery of 4‐(isopentyloxy)‐3‐nitrobenzamide derivatives as xanthine oxidase inhibitors through a non‐anthraquinone exploration
Authors: Guo Shuai , Sun Qi , Zhang Xu , Li Song‐ye , Liu Hong‐ye , Ge Gong‐hui , Wang Jing , Liu Xing‐yang , Xu Ben , Li Ting‐ting , Zhou Xian‐feng , Wang Yan‐ping , Meng Fan‐hao , Zhang Ting‐jian
Published: July 2024

In our previous study, we reported a series of N‐(9,10‐anthraquinone‐2‐carbonyl) amino acid derivatives as novel inhibitors of xanthine oxidase (XO). Recognizing the suboptimal drug‐like properties associated with the anthraquinone moiety, we embarked on a nonanthraquinone medicinal chemistry exploration in the current investigation. Through systematic structure–activity relationship (SAR) studies, we identified a series of 4‐(isopentyloxy)‐3‐nitrobenzamide derivatives exhibiting excellent in vitro potency against XO. The optimized compound, 4‐isopentyloxy‐N‐(1H‐pyrazol‐3‐yl)‐3‐nitrobenzamide (6k), demonstrated exceptional in vitro potency with an IC50 value of 0.13 μM. Compound 6k showed favorable drug‐like characteristics with ligand efficiency (LE) and lipophilic ligand efficiency (LLE) values of 0.41 and 3.73, respectively. In comparison to the initial compound 1d, 6k exhibited a substantial 24‐fold improvement in IC50, along with a 1.6‐fold enhancement in LE and a 3.7‐fold increase in LLE. Molecular modeling studies provided insights into the strong interactions of 6k with critical amino acid residues within the active site. Furthermore, in vivo hypouricemic investigations convincingly demonstrated that 6k significantly reduced serum uric acid levels in rats. The MTT results revealed that compound 6k is nontoxic to healthy cells. The gastric and intestinal stability assay demonstrated that compound 6k exhibits good stability in the gastric and intestinal environments. In conclusion, compound 6k emerges as a promising lead compound, showcasing both exceptional in vitro potency and favorable drug‐like characteristics, thereby warranting further exploration.
A novel indole derivative, 2‐{3‐[1‐(benzylsulfonyl)piperidin‐4‐yl]‐2‐methyl‐1H‐indol‐1‐yl}‐1‐(pyrrolidin‐1‐yl)ethenone, suppresses hedgehog signaling and drug‐resistant tumor growth
Authors: Jung Joo Hyun , Lee Hwayoung , Jeon Jiyeon , Lee Yoon Ji , Nada Hossam , Kim Minkyoung , Lee Hankyu , Bhattarai Deepak , Lee Kyeong , Ko Hyuk Wan
Published: July 2024

The Hedgehog (Hh) signaling pathway plays important roles in various physiological functions. Several malignancies, such as basal cell carcinoma (BCC) and medulloblastoma (MB), have been linked to the aberrant activation of Hh signaling. Although therapeutic drugs have been developed to inhibit Hh pathway‐dependent cancer growth, drug resistance remains a major obstacle in cancer treatment. Here, we show that the newly identified, 2‐{3‐[1‐(benzylsulfonyl)‐1,2,3,6‐tetrahydropyridin‐4‐yl]‐2‐methyl‐1H‐indol‐1‐yl}‐1‐(pyrrolidin‐1‐yl)ethenone analog (LKD1214) exhibits comparable potency to vismodegib in suppressing the Hh pathway activation. LKD1214 represses Smoothened (SMO) activity by blocking its ciliary translocation. Interestingly, we also identified that it has a distinctive binding interface with SMO compared with other SMO‐regulating chemicals. Notably, it maintains an inhibitory activity against the SmoD477H mutant, as observed in a patient with vismodegib‐resistant BCC. Furthermore, LKD1214 inhibits tumor growth in the mouse model of MB. Collectively, these findings suggest that LKD1214 has the therapeutic potential to overcome drug‐resistance in Hh‐dependent cancers.
The significant yet short‐term influence of research covidization on journal citation metrics
Authors: Zheng Xiang , Ni Chaoqun
Published: July 2024

COVID‐19 has emerged as a major research hotspot and trending topic in recent years, leading to increased publications and citations of related papers. While concerns exist about the potential citation boost in journals publishing these papers, the specifics are not fully understood. This study uses a generalized difference‐in‐differences approach to examine the impact of publishing COVID‐19 papers on journal citation metrics in the Health Sciences fields. Findings indicate that journals publishing COVID‐19 papers in 2020 received significantly higher citation premiums due to COVID‐19 in 2020 and continued to benefit from the premium in 2021 in certain fields. In contrast, journals that began publishing COVID‐19 papers in 2021 experienced weaker citation premiums. The citation premiums exhibit some negative spillover effect: Although the publication volume of non‐COVID‐19 papers also surged, these papers experienced insignificant or negative citation gains, even when published in the same journals as COVID‐19 papers. COVID‐19 papers published in high‐impact journals brought higher citation premiums than those in low‐impact journals in most fields, indicating a potential Matthew effect. These citation premiums can affect various citation‐based journal metrics, such as our simulated impact factor and SCImago Journal Rank, to different degrees. Compared to the simulated impact factor, other normalized journal metrics are less influenced by citation premiums. The results highlight a “gold rush” pattern in which early entrants establish their citation advantage in research hotspots and caution against using citation‐based metrics for research assessment.
Event‐triggered dynamic output feedback control for switched linear neutral systems under time‐varying delays and frequent asynchronism
Authors: Yan Rongrong , Wu Baowei , Wang Yue‐E , Liu Lili , Li Wenzi , Huang Liqiong
Published: July 2024

The study focuses on the event‐triggered dynamic output feedback control for a type of switched linear neutral systems under time‐varying delays and frequent asynchronism. Distinct from the existing literatures about asynchronous switching, which restricts the minimum dwell time, frequent switching is allowed to occur within each inter‐event interval by reason of average dwell time method. Then, concentrated on switched neutral time‐delay system, a novel sufficient condition is established under which proposed event‐triggered control scheme guarantees its the global uniform exponential stability by using the controller‐mode‐dependent Lyapunov functional together with dynamic output feedback controller. Subsequently, the sufficient criteria are deduced for co‐designing the dynamic output feedback controller and mode‐dependent event‐triggered mechanism. Additionally, it is proved that a positive minimum threshold on the inter‐event intervals exists, which eliminates Zeno phenomenon. In the end, a numerical simulation indicates the efficacy of the acquired results.
Red‐emitting 4‐methyl coumarin fused barbituric acid as an electrochemical sensor for catechol detection and probe for latent fingerprints
Authors: Yashyanaik Surendranaik , Venkatesh Talavara , Ereshnaik  , Vinuth Mirle
Published: July 2024

Herein, we have reported a red‐emitting 4‐methyl coumarin fused barbituric acid azo dye (4‐MCBA) synthesized by conventional method. Density functional theory (DFT) studies of tautomer compounds were done using (B3LYP) with a basis set of 6‐31G(d,p). NLO analysis has shown that tautomer has mean first‐order hyperpolarisabilities (β) value of 1.8188 × 10−30 esu and 1.0470 × 10−30 esu for azo and hydrazone forms, respectively, which is approximately nine and five times greater than the magnitude of urea. 4‐MCBA exhibited two absorption peaks in the range of 290–317 and 379–394 nm, and emission spectra were observed at 536 nm. CV study demonstrated that the modified 4‐MCBA/MGC electrode exhibited excellent electrochemical sensitivity towards the detection of catechol and the detection limit is 9.39 μM under optimum conditions. The 4‐MCBA employed as a fluorescent probe for the visualisation of LFPs on various surfaces exhibited Level‐I to level‐II LFPs, with low background interference.
Non‐industrial production of therapeutic lentiviral vectors: How to provide vectors to academic CAR‐T
Authors: Keyer Viktoriya , Syzdykova Laura , Ingirbay Bakytkali , Sedova Elena , Zauatbayeva Gulzat , Kulatay Tolganay , Shevtsov Alexandr , Shustov Alexandr V.
Published: July 2024

Bringing effective cancer therapy in the form of chimeric antigen receptor technology to untapped markets faces numerous challenges, including a global shortage of therapeutic lentiviral or retroviral vectors on which all current clinical therapies using genetically modified T cells are based. Production of these lentiviral vectors in academic settings in principle opens the way to local production of therapeutic cells, which is the only economically viable approach to make this therapy available to patients in developing countries.

The conditions for obtaining and concentrating lentiviral vectors have been optimized and described. The calcium phosphate precipitation method was found to be suitable for transfecting high cell‐density cultures, a prerequisite for high titers. We describe protocols for gradually increasing production from 6‐well plates to P100 plates, T‐175 flasks, and 5‐layer stacks while maintaining high titers, >108 transducing units. Concentration experiments using ultracentrifugation revealed the advantage of lower centrifugation speeds compared to competing protocols. The resulting batches of lentiviral vectors had a titer of 1010 infectious particles and were used to transduce primary human T lymphocytes generating chimeric antigen receptor T cells, the quality of which was checked and found potential applicability for treatment.
Novel allosteric glutaminase inhibitors with macrocyclic structure activity relationship analysis (part 2)
Authors: Lee Eun Ji , Jang Jiyoon , Cyriac Rajath , Yun Mi Ran , Kwon Yeongju , Jung Myoung Eun , Choi Gildon , Chae Chong Hak , Cho Byoung Chul , Lee Kwangho
Published: July 2024

Glutamine‐addicted cancer metabolism is recently recognized as novel cancer target especially for KRAS and KEAP1 co‐occurring mutations. To identify more drug‐like GLS inhibitors, we report the amides in the wing macrocycles for GLS inhibition with unique SAR analysis. Although the amidotriazoles (amides in the wing) are in general less potent than those of acylaminothiadiazole analogs (reverse amides in the wing), macrocycle 4, 5, and 7 are selected as a potent macrocyclic GLS inhibitor in both biochemical and cell viability assays. Selected molecules result in partial reduction in intracellular glutamate levels in LR (LDK378‐resistant) cells which is consistent to their cells viability result. Finally, selected compounds reduce the growth of A549 and H460 cells which have co‐occurring mutations including KRAS and KEAP1. The putative binding mode of macrocycle 4 is also suggested using a molecular docking model.
Sustainability reporting in carbon‐intensive industries: Insights from a cross‐sector machine learning approach
Authors: Crocco Edoardo , Broccardo Laura , Alofaysan Hind , Agarwal Reeti
Published: July 2024

Due to climate change concerns, academics and practitioners focus more on environmental management and sustainability. Accounting researchers have focused on corporate environmental disclosure and sustainability reporting in response to stakeholder demand for openness and accountability. Thus, scholarly studies on sustainability reporting have gained momentum with the frequent use of qualitative text analysis to assess company disclosures' completeness and quality. However, sustainability reporting research has major limitations wherein past studies have focused on certain sectors or qualitative content analysis. Coherently with the abovementioned gap, our study intends to examine sustainability reports of companies in agriculture, conventional energy, heavy industry and manufacturing, transport and automotive, and construction, the highly carbon‐intensive industries most vulnerable to physical climate damage and net‐zero transition risk. In doing so, the goal of the present research is to investigate sustainability reporting practice on a larger, cross‐sectoral scale by using automated, machine learning‐powered text analysis methods to complement and strengthen qualitative research results that scholars have previously obtained. The latent Dirichlet allocation topic modelling technique has been used to examine companies' sustainability efforts and identify industry‐specific subtopics based on quantitative distribution. The originality of our analysis lies in determining how companies prioritise issues in sustainability reports. By comparing reports from different industries, we also identify sector‐specific patterns and how organisations in highly carbon‐intensive industries that are most exposed to physical climate damage and net‐zero transition risk prioritise certain themes over others, as well as identifying what type of content is overall more prominently featured in reports, regardless of the industry. Our study adds to sustainability reporting literature by investigating a previously unstudied sample of sectors. Moreover, our study informs practitioners of existing sustainability reporting procedures. The subject model and a cross‐industry view can advise policymakers and industry of which themes are under‐disclosed and what industry‐specific rules may be desirable to suit sector‐specific needs.
Carbon accounting and integrated reporting for net‐zero business models towards sustainable development: A systematic literature review
Authors: Di Vaio Assunta , Zaffar Anum , Chhabra Meghna , Balsalobre‐Lorente Daniel
Published: July 2024

This study highlights the main concerns regarding firms' carbon accounting and decarbonization practices. Under institutional, legitimacy and stakeholder theories, this study analyses the linkages between carbon accounting outputs and integrated reporting (IR), as well as between disclosure assurance systems in the transition towards net‐zero business models (n‐ZBMs). This study emphasizes the awareness of accounting tools to be considered environmental and social measures due to decarbonization practices. This study developed a systematic literature review (SLR) of 433 English articles published in Scopus database and Google Scholar between the years 1990 and 2024. It is a consolidated methodological approach in the ‘sustainability accounting’ research field to fill the existing gaps that justify this study. The results of this study highlight that IR and carbon accounting awareness enhance firms' performance and have positive social and environmental impacts with the adoption of decarbonization practices towards n‐ZBMs through an improved understanding of stakeholders and regulatory pressures. This study is the first to explore the relationship between carbon accounting awareness and IR about the decarbonization practices, as well as the role of assurance in the transition for n‐ZBMs. This study tries to move from the concept of legitimacy of the decarbonization practices that firms aim to achieve through sustainable disclosure to the legitimacy of business models towards net‐zero emissions.
How do firms develop and financially benefit from green product innovation in a developing country? Roles of innovation orientation and green marketing innovation
Authors: Appiah Listowel Owusu , Essuman Dominic
Published: July 2024

While previous research has explored the antecedents and outcomes of green product innovation, empirical evidence remains inconclusive. This study draws on the contingent natural resource–based view to conceptualize how innovation orientation enables firms to develop green product innovation to enhance financial performance, especially where they emphasize green marketing innovation. The study tests its hypotheses using primary survey data from 347 small and medium enterprises (SMEs) in Ghana and PROCESS as an analytical tool. The results suggest that innovation orientation has a positive relationship with green product innovation and that green product innovation mediates the relationship between innovation orientation and financial performance. Additional results indicate that green product innovation contributes more to financial performance under increasing levels of green marketing innovation. The article sheds new light on how firms can combine innovation orientation, green product innovation, and green marketing innovation to boost financial performance in a developing country.
It's like Jenga: A collaborative autoethnography study into facilitators' experiences of a person‐centred community of practice, focused on critical thinking skills for counselling and psychotherapy students
Authors: Blundell Peter , Hall Madeline
Published: July 2024

Background

Communities and groups based on person‐centred theoretical principles are often a core part of counselling and psychotherapy training within this modality, yet no research has been undertaken that considers these groups as a community of practice . Furthermore, no research has been undertaken that explores the impact of these groups when they are run alongside, rather than as part of, the curriculum.

Aims

This study explores our experiences of facilitating a community of practice for trainee personcentred/experiential therapists that focused on critical thinking skills. This community was established over a 12‐week period and was attended by students from across 3‐year groups.

Methods

Using collaborative autoethnography to explore these encounters, we identify four key aspects of our experience of this community.

Results

The following aspects were identified: (1) Fecund and Fruitful—A Space for Growth; (2) Freedom to Learn; (3) Jenga!—Navigating the Dimensions of Community Facilitator; and (4) Power and Control.

Discussion

This study centres on the idea of student‐centred learning as a way of challenging hegemonic notions of education and learning within higher educational settings.

Conclusion

These findings could help others set up and facilitate other communities of practice based on person‐centred principles, in counselling and psychotherapy training, or other associated fields of study.
High Rotational Barrier Atropisomers
Authors: Fragkiadakis Michael , Thomaidi Maria , Stergiannakos Taxiarchis , Chatziorfanou Eleftheria , Gaidatzi Maria , Michailidis Barakat Alaelddin , Stoumpos Constantinos , Neochoritis Constantinos G.
Published: July 2024

Atropisomers have attracted a great deal of attention lately due to their numerous applications in organic synthesis and to their employment in drug discovery. However, the synthetic arsenal at our disposal with which to access them remains limited. The research described herein is two‐pronged; we both demonstrate the use of MCR chemistry as a synthetic strategy for the de novo synthesis of a class of atropisomers having high barriers to rotation with the simultaneous insertion of multiple chiral elements and we study these unprecedented molecular systems by employing a combination of crystallography, NMR and DFT calculations. By fully exploiting the synthetic capabilities of our chemistry, we have been able to monitor a range of different types of interaction, i. e. π‐π, CH–π, heteroatom‐π and CD–π, in order to conduct structure‐property studies. The results could be applied both to atroposelective synthesis and in drug discovery.
Mechanochemical Synthesis of Corannulene Flanked N‐heterocyclic Carbene (NHC) Precursors and Preparation of Their Metal Complexes
Authors: Hum Gavin , Muzammil Ezzah M. , Li Yongxin , García Felipe , Stuparu Mihaiela C.
Published: July 2024

The synthesis of new compounds is an important pillar for the advancement of the field of chemistry and adjacent fields. In this regard, over the last decades huge efforts have been made to not only develop new molecular entities but also more efficient sustainable synthetic methodologies due to the increasing concerns over environmental sustainability. In this context, we have developed synthetic routes to novel corannulene flanked imidazolium bromide NHC precursors both in the solid‐state and solution phases. Our work presents a comprehensive comparative study of mechanochemical routes and conventional solution‐based methods. Green metrics and energy consumption comparison were performed for both routes revealing ball‐milling generation of these compounds to be an environmentally greener technique to produce such precursors compared to conventional solvent‐based methods. In addition, we have demonstrated proof‐of‐concept of the herein reported corannulene flanked NHCs to be robust ligands for transition metals and their ligand substitution reactions.
Intramolecular Nucleophilic Vinylic Substitution (SNV) by Carbon Nucleophiles: Conformationally Directed Formation of Dienes from N,N’‐Diallyl Ureas
Authors: van Veen Branca C. , Clayden Jonathan
Published: July 2024

Nucleophilic vinylic substitution (SNV) by carbon nucleophiles allows the formation of vinylic C−C bonds without transition metal catalysts. In this paper, we show that tethering two alkenes together through a urea linkage can lead to the formation of a diene by an intramolecular SNV reaction. The starting materials are fully substituted N,N’‐diallyl ureas; the reaction proceeds in the presence of base, and entails a cascade of deprotonations, reprotonations, and an SNV reaction of an allylic carbanion on a rare electrophile: a vinylic urea. As a result, two allylic substituents couple to form a diene, despite the fact that neither is activated towards electrophilic attack. The reaction is tolerant of significant steric bulk, and exhibits regioselectivity with unsymmetrical diallyl ureas: β‐substituted allyl groups invariably behave as nucleophiles, while electrophilic behavior may be enforced by the use of an E‐vinylic urea substituent that cannot be deprotonated under the reaction conditions.
Ion migration – innovative low‐cost experiments
Authors: Ducci Matthias
Published: July 2024

Im Beitrag werden neu entwickelte Low‐Cost‐Experimente zur Demonstration der Ionenwanderung im elektrischen Feld präsentiert. Als Versuchsgefäß dient ein Blister aus dem Zeichenbedarf. Die Salze werden zunächst in Alginatbällchen eingeschlossen, aus denen sie sukzessive in die umgebende Flüssigkeit diffundieren. Hierzu werden auch Substanzen mit fluoreszierenden Ionen verwendet
Breast segmentation in infrared thermography from characteristical inframammary shape
Authors: Alvarez‐Padilla Francisco J. , Flores‐Nunez Jorge L. , Alvarez‐Padilla Juan R. , Gonzalez Francisco J. , Oceguera‐Villanueva Antonio , Gutierrez‐Quiroz Brian A.
Published: July 2024

Infrared thermography is gaining relevance in breast cancer assessment. For this purpose, breast segmentation in thermograms is an important task for performing automatic image analysis and detecting possible temperature changes that indicate the presence of malignancy. However, it is not a simple task since the breast limit borders, especially the top borders, often have low contrast, making it difficult to isolate the breast area. Several algorithms have been proposed for breast segmentation, but these highly depend on the contrast at the lower breast borders and on filtering algorithms to remove false edges. This work focuses on taking advantage of the distinctive inframammary shape to simplify the definition of the lower breast border, regardless of the contrast level, which indeed also provides a strong anatomical reference to support the definition of the poorly marked upper boundary of the breasts, which has been one of the major challenges in the literature. In order to demonstrate viability of the proposed technique for an automatic breast segmentation, we applied it to a database with 180 thermograms and compared their results with those reported by others in the literature. We found that our approach achieved a high performance, in terms of Intersection over Union of 0.934, even higher than that reported by artificial intelligence algorithms. The performance is invariant to breast sizes and thermal contrast of the images.
Eco‐Friendly Transformation of Bioethanol into Ethylene over Bimetallic Nickel‐Copper Catalysts
Authors: Gaitán Chavarría Emily , Picado Espinoza Thamara , Durán Herrera Esteban , Miranda Morales Bárbara Cristina
Published: July 2024

The conversion of bioethanol to ethylene in gas phase and atmospheric pressure was investigated over γ‐Al2O3 supported copper and nickel catalysts. These catalysts were prepared by co‐precipitation and pre‐treated with hydrogen at 450 °C. Six catalysts were studied at 450 °C under a nitrogen atmosphere. It was found that the monometallic Cu/γ‐Al2O3 catalyst exhibited the highest ethylene concentration, with a selectivity of around 90 %. The bioethanol conversion obtained was between 57 %‐86 %. Another catalyst that exhibited high concentration values was the NiCu1 : 7 bimetallic catalyst. The catalysts were characterised using XRD, SEM, EDS, TEM, TGA, FTIR, Raman, and N2‐physisoption techniques. Furthermore, the Cu/γ‐Al2O3 catalyst was studied under different reduction temperatures and gas flow conditions. It was found that the catalysts reduced at 350 °C and 35 ml/min N2 flow presented ethylene concentrations between (0.18–0.21) g/L. Moreover, the catalyst deactivation was identified to be first order and the equation of the Cu/γ‐Al2O3 catalyst deactivation model was determined. Carbonaceous deposits over the used sample were not detected by Raman and FTIR. It was determined that the Cu/γ‐Al2O3 catalyst deactivation could be mainly attributed to the blocking of the catalytic sites by strongly adsorbed compounds and hydroxylation of the catalyst surface.
Imidazolium and Pyridinium‐Based Ionic Porous Organic Polymers: Advances in Transformative Solutions for Oxoanion Sequestration and Non‐Redox CO2 Fixation
Authors: Sahoo Aniket , Jaiswal Shilpi , Das Subhadeep , Patra Abhijit
Published: July 2024

The rapid pace of industrialization has led to a multitude of detrimental environmental consequences, including water pollution and global warming. Consequently, there is an urgent need to devise appropriate materials to address these challenges. Ionic porous organic polymers (iPOPs) have emerged as promising materials for oxoanion sequestration and non‐redox CO2 fixation. Notably, iPOPs offer hydrothermal stability, structural tunability, a charged framework, and readily available nucleophilic counteranions. This review explores the significance of pores and charged functionalities alongside design strategies outlined in existing literature, mainly focusing on the incorporation of pyridinium and imidazolium units into nitrogen‐rich iPOPs for oxoanion sequestration and non‐redox CO2 fixation. The present review also addresses the current challenges and future prospects, delineating the design and development of innovative iPOPs for water treatment and heterogeneous catalysis.
Development of Pyrene Embedded Luminophore via π‐linker: Room Temperature Phosphorescence (RTP) and Sensing towards Nitroaromatics (NACs)
Authors: Jamuna Kannan , Govindharaj Prasannamani , Krishnan Aravind , Savitha Devi Natarajan , Sebastian Amal Tom , Selvapalam Narayanan , Mukherjee Moubani , Data Przemyslaw , Gayathri Santhalingum , Sivakumar Shanmugam , Ashokkumar Balasubramaniem
Published: July 2024

A pyrene base luminophore was designed and synthesised under ambient conditions using [4+2] annulation. The synthesised probe PYINDP exhibits good optical properties and emits greenish blue, with high colour purity in solid, solution, and thin film phases. In solution, the CIE coordinates were found to be (0.20, 0.48), and for an aggregated state emitting deep green colour, the CIE values are (0.27, 0.65). Room temperature phosphorescence (RTP) is generated by the luminophore PYINDP, owing to the ISC process. Moreover, the emitter demonstrated an excellent limit of detection values in detecting nitroaromatics (NACs). Bio‐imaging studies on HEK, A549 cell lines were successfully carried out to verify the staining capability of PYINDP in biological systems.
Association of transketolase polymorphisms with diabetic polyneuropathy in the general population: The KORA F4 study
Authors: Ziegler Dan , Thorand Barbara , Strom Alexander , Bönhof Gidon J. , Knebel Birgit , Schleicher Erwin , Rathmann Wolfgang , Herder Christian , Maalmi Haifa , Gieger Christian , Heier Margit , Meisinger Christine , Roden Michael , Peters Annette , Grallert Harald
Published: July 2024

Aims

We recently reported that genetic variability in the TKT gene encoding transketolase, a key enzyme in the pentose phosphate pathway, is associated with measures of diabetic sensorimotor polyneuropathy (DSPN) in recent‐onset diabetes. Here, we aimed to substantiate these findings in a population‐based KORA F4 study.

Materials and Methods

In this cross‐sectional study, we assessed seven single nucleotide polymorphisms (SNPs) in the transketolase gene in 952 participants from the KORA F4 study with normal glucose tolerance (NGT; n = 394), prediabetes (n = 411), and type 2 diabetes (n = 147). DSPN was defined by the examination part of the Michigan Neuropathy Screening Instrument (MNSI) using the original MNSI > 2 cut‐off and two alternative versions extended by touch/pressure perception (TPP) (MNSI > 3) and by TPP plus cold perception (MNSI > 4).

Results

After adjustment for sex, age, BMI, and HbA1c, in type 2 diabetes participants, four out of seven transketolase SNPs were associated with DSPN for all three MNSI versions (all p ≤ 0.004). The odds ratios of these associations increased with extending the MNSI score, for example, OR (95% CI) for SNP rs62255988 with MNSI > 2: 1.99 (1.16–3.41), MNSI > 3: 2.27 (1.26–4.09), and MNSI > 4: 4.78 (2.22–10.26); SNP rs9284890 with MNSI > 2: 2.43 (1.42–4.16), MNSI > 3: 3.46 (1.82–6.59), and MNSI > 4: 4.75 (2.15–10.51). In contrast, no associations were found between transketolase SNPs and the three MNSI versions in the NGT and prediabetes groups.

Conclusions

The link of genetic variation in transketolase enzyme to diabetic polyneuropathy corroborated at the population level strengthens the concept suggesting an important role of pathways metabolising glycolytic intermediates in the evolution of diabetic polyneuropathy.
Tardigrade distribution in soils of high Arctic habitats
Authors: Tůmová Michala , Jílková Veronika , Macek Petr , Devetter Miloslav
Published: July 2024

Tardigrades are omnipresent microfauna with scarce record on their ecology in soils. Here, we investigated soil inhabiting tardigrade communities in five contrasting polar habitats, evaluating their abundance, diversity, species richness, and species composition. Moreover, we measured selected soil physico‐chemical properties to find the drivers of tardigrade distribution among these habitats. In spite of reported tardigrade viability in extreme conditions, glacier forelands represented a habitat almost devoid of tardigrades. Even dry and wet tundra with soil developing for over more than 10 000 years held low abundances compared to usual numbers of tardigrades in temperate habitats. Polar habitats also differ in species composition, with Diaforobiotus islandicus being typical species for dry and Hypsibius exemplaris for wet tundra. Overall, tardigrade abundance was affected by the content of nutrients as well as physical properties of soil, i.e. content of total nitrogen (TN), total organic carbon (TOC), stoniness, soil texture and the water holding capacity (WHC). While diversity and species composition were significantly related to soil physical properties such as the bulk density (BD), soil texture, stoniness, and WHC. Physical structure of environment was, therefore, an important predictor of tardigrade distribution in polar habitats. Since many studies failed to identify significant determinants of tardigrade distribution, we encourage scientists to include physical properties of tardigrade habitats as explanatory variables in their studies.
Complete chloroplast genomes of the hemiparasitic genus Cymbaria: Insights into comparative analysis, development of molecular markers, and phylogenetic relationships
Authors: Ma Yang , López‐Pujol Jordi , Yan Dongqing , Zhou Zhen , Deng Zekun , Niu Jianming
Published: July 2024

The hemiparasitic tribe Cymbarieae (Orobanchaceae) plays a crucial role in elucidating the initial stage of the transition from autotrophism to heterotrophism. However, the complete chloroplast genome of the type genus Cymbaria has yet to be reported. In addition, the traditional Mongolian medicine Cymbaria daurica is frequently subjected to adulteration or substitution because of the minor morphological differences with Cymbaria mongolica. In this study, the complete chloroplast genomes of the two Cymbaria species were assembled and annotated, and those of other published 52 Orobanchaceae species were retrieved for comparative analyses. We found that the Cymbaria chloroplast genomes are characterized by pseudogenization or loss of stress‐relevant genes (ndh) and a unique rbcL–matK inversion. Unlike the high variability observed in holoparasites, Cymbaria and other hemiparasites exhibit high similarity to autotrophs in genome size, guanine–cytosine (GC) content, and intact genes. Notably, four pairs of specific DNA barcodes were developed and validated to distinguish the medicinal herb from its adulterants. Phylogenetic analyses revealed that the genus Cymbaria and the Schwalbea–Siphonostegia clade are grouped into the tribe Cymbarieae, which forms a sister clade to the remaining Orobanchaceae parasitic lineages. Moreover, the diversification of monophyletic Cymbaria occurred during the late Miocene (6.72 Mya) in the Mongol–Chinese steppe region. Our findings provide valuable genetic resources for studying the phylogeny of Orobanchaceae and plant parasitism, and genetic tools to validate the authenticity of the traditional Mongolian medicine “Xinba.”
Size‐specific reduction in kelp consumption by New Zealand urchins exposed to chemical cues from the red rock lobster
Authors: Curtis Joseph S. , Wing Stephen R.
Published: July 2024

Sea urchins can strongly reduce their mobility, exposure to predation, and feeding rates upon detection of chemical cues produced by predators, driving behavioral effects on grazing activity that may contribute to macroalgal community dynamics. However, the extent of chemically induced antipredator behaviors in urchins can vary by predator–prey species pair and ecological context and is therefore important to characterize in novel settings. Additionally, the effect of predator and prey size on urchin reactions to predator cues has rarely been considered, with the few existing examples yielding mixed conclusions. Here, we used a replicated split‐plot experiment to measure the effects of red rock lobsters (Jasus edwardsii) on consumption of macroalgae by the New Zealand sea urchin (Evechinus chloroticus) across a range of predator and prey body sizes. Overall, per‐capita consumption rates of kelp by urchins declined by 30% in the presence of lobsters, though feeding activity varied widely among individuals. Based on mass‐specific measurements of feeding rates, responses to predator cues appeared similar across all urchin sizes but only yielded distinguishable differences in the amount of kelp consumed in trials with larger urchins due to their considerably higher feeding capacity. Conversely, consumption rates of kelp by urchins had no apparent relationship with lobster size, likely due to chemical cue saturation in our experimental setting or a risk gradient that was insufficient to elicit a graded behavioral response. Our findings provide new evidence for a nonconsumptive effect of lobsters on feeding rates of an important grazer that can potentially reinforce the ecological role of this key predator in New Zealand kelp beds.
Remotely sensed crown nutrient concentrations modulate forest reproduction across the contiguous United States
Authors: Qiu Tong , Clark James S. , Kovach Kyle R. , Townsend Philip A. , Swenson Jennifer J.
Published: July 2024

Global forests are increasingly lost to climate change, disturbance, and human management. Evaluating forests' capacities to regenerate and colonize new habitats has to start with the seed production of individual trees and how it depends on nutrient access. Studies on the linkage between reproduction and foliar nutrients are limited to a few locations and few species, due to the large investment needed for field measurements on both variables. We synthesized tree fecundity estimates from the Masting Inference and Forecasting (MASTIF) network with foliar nutrient concentrations from hyperspectral remote sensing at the National Ecological Observatory Network (NEON) across the contiguous United States. We evaluated the relationships between seed production and foliar nutrients for 56,544 tree‐years from 26 species at individual and community scales. We found a prevalent association between high foliar phosphorous (P) concentration and low individual seed production (ISP) across the continent. Within‐species coefficients to nitrogen (N), potassium (K), calcium (Ca), and magnesium (Mg) are related to species differences in nutrient demand, with distinct biogeographic patterns. Community seed production (CSP) decreased four orders of magnitude from the lowest to the highest foliar P. This first continental‐scale study sheds light on the relationship between seed production and foliar nutrients, highlighting the potential of using combined Light Detection And Ranging (LiDAR) and hyperspectral remote sensing to evaluate forest regeneration. The fact that both ISP and CSP decline in the presence of high foliar P levels has immediate application in improving forest demographic and regeneration models by providing more realistic nutrient effects at multiple scales.
Enantiomeric separation of nefopam and cathinone derivatives using a supramolecular deep eutectic solvent as a chiral selector in capillary electrophoresis
Authors: Ioannou Katerina A. , Georgiou Maria N. , Ioannou Georgia D. , Christou Atalanti , Stavrou Ioannis J. , Schmid Martin G. , Kapnissi‐Christodoulou Constantina P.
Published: July 2024

The present study investigates the utilization of a supramolecular deep eutectic solvent (SUPRADES), consisting of sulfated‐β‐cyclodextrin (S‐β‐CD) and citric acid (CA), as a chiral selector (CS) in capillary electrophoresis for the enantiomeric separation of nefopam (NEF) and five cathinone derivatives (3‐methylmethcathinone [3‐MMC], 4‐methylmethcathinone [4‐MMC], 3,4‐dimethylmethcathinone [3,4‐DMMC], 4‐methylethcathinone [4‐MEC], and 3,4‐methylendioxycathinone [MDMC]). A significant improvement in enantiomeric separation of the target analytes was observed upon the addition of S‐β‐CD‐CA to the background electrolyte (BGE), leading to a baseline separation of all analytes. In particular, the optimum percentage of S‐β‐CD‐CA, added to the BGE, was determined to be 0.075% v/v for NEF (Rs = 1.5) and 0.050% v/v for three out of five cathinone derivatives (Rs = 1.5, 1.6, and 2.4 for 3‐MMC, 4‐MEC, and 3,4‐DMMC, respectively). In the case of 4‐MMC and MDMC, a higher percentage of the CS, equal to 0.075% and 0.10% v/v, respectively, was required to achieve baseline separation (Rs = 1.5, 1.9 for MDMC and 4‐MMC, respectively). The outcomes of the present study highlight the potential effectiveness of using SUPRADES as a CS in electrophoretic enantioseparations.
MOF‐derived Co/C‐anchored MoS2‐based phase change materials toward thermal management and microwave absorption
Authors: Li Yang , Han Xukang , Zhu Jiaying , Feng Yuhao , Liu Panpan , Chen Xiao
Published: July 2024

With the miniaturization and integration of electronic devices, developing advanced multifunctional phase change materials (PCMs) integrating thermal storage, thermal conduction, and microwave absorption to address electromagnetic interference, thermal dissipation, and instantaneous thermal shock is imperative. Herein, we proposed an extensible strategy to synthesize MOF‐derived Co/C‐anchored MoS2‐based PCMs using high‐temperature carbonation of flower‐like MoS2 grown in situ by ZIF67 and vacuum impregnation of paraffin. The resulting MoS2@Co/C‐paraffin composite PCMs exhibited good thermal storage density, thermal cycling stability, and long‐term durability. The thermal conductivity of composite PCMs was 44% higher than that of pristine paraffin due to the construction of low interfacial thermal resistance. More attractively, our designed composite PCMs also possessed −57.15 dB minimum reflection loss at 9.2 GHz with a thickness of 3.0 mm, corresponding to an effective absorption bandwidth of 3.86 GHz. The excellent microwave absorption was attributed to the multicomponent synergy of magnetic loss from Co nanoparticles and conductive loss from MOF‐derived carbon layers, and multiple reflection of MoS2 nanowrinkle, along with good impedance matching. This study provided a meaningful reference for the widespread application of composite PCMs combining thermal storage, thermal conduction, and microwave absorption in high‐power miniaturized electronic devices.