bluuebunny/crossref_metadata_2025 huggingface dataset:
Cleavage and Reassembly of 1,3‐Dicarbonyls with Enaminones to Synthesize Highly Functionalized Naphthols
Authors: Zhou Shuguang , Liu Xin , Zhang Tao , Loh Teck‐Peng , Tian Jie‐Sheng
Published: December 2024

The cleavage of carbon‐carbon bonds and their subsequent reassembly into highly functionalized and useful molecules in an atom‐efficient manner has always been a central focus in the realm of organic synthesis. In this report, we describe the construction of highly functionalized naphthol esters via a tandem reassembly process, driven by Ullmann‐type coupling of enaminones and 1,3‐dicarbonyl compounds. Mechanistic investigations suggest the involvement of C(sp2)‐C(sp3) coupling, cyclization, two acyl migrations, aromatization, and additional transformations within this tandem sequence. This methodology offers several notable advantages, such as the use of inexpensive and easily accessible starting materials, the elimination of the need for expensive transition metal catalysis, simple operation in the atmosphere, exceptional compatibility with a wide range of substrates, and ease of conversion into drug scaffolds.
Cooperative Multiscale‐Assembly for Directional and Hierarchical Growth of Highly Oriented Porous Organic Cage Single‐Crystal Microtubes and Arrays
Authors: Liu Si‐Hua , Zhao Ke , Zhou Jun‐Hao , Dong Kang , Ai Hui , Liu Pai , Cui Jing‐Wang , Zhang Yun‐Hong , Puigmartí‐Luis Josep , Sun Jian‐Ke
Published: December 2024

The directional assembly of porous organic molecules into long‐range ordered architectures, featuring controlled hierarchical porosity and oriented pore channels with defined spatial arrangements, is a fundamental challenge in chemistry and materials science. Herein, using porous organic cages as starting units, we present a cooperative multiscale‐assembly strategy enabling the simultaneous alignment of pore channels and directional hierarchical growth in a single step. At the microscopic level, we employed double solvents to manipulate the intermolecular packing of microporous tetrahedral [4+6] imine cages (CC1 and CC3), resulting in pore channel orientation. Concurrently, at the mesoscopic level, convective flow in the double‐solvent system directed the spatial distribution of nuclei species, followed by diffusion limited growth, leading to the directional formation of single‐crystal microtubes. By precisely controlling the direction of convective flow, the nanocages were successfully organized into 2D and 3D single‐crystal microtube arrays while maintaining oriented micropores. This hierarchical porous architecture enhanced mass transfer, as confirmed by adsorption measurements. Interestingly, such 3D hierarchical microtube arrays can be utilized to immobilize Pd clusters and enzymes (lipase or Glucose oxidase) within the micro‐ and macropores, respectively, showing a 3.8‐ to 4‐fold enhancement in one‐pot tandem reaction activity compared to physical mixtures of individual analogues.
Synthesis of γ‐Amino Amides by Iridium‐Catalyzed Enantioselective Hydroamination of Internal Alkenes Directed by an Amide
Authors: Sun Yu‐Wen , Sun Xin , Tan Hao‐Tian , Li Bi‐Jie
Published: December 2024

Catalytic regio‐ and enantioselective hydroamination of less activated internal alkenes presents a challenge to synthetic chemists due to their low reactivity and the difficulty in simultaneously controlling regio‐ and enantioselectivities. Here, we report an iridium‐catalyzed enantioselective hydroamination of internal alkenes directed by an amide. The amide group on the alkene effectively directs the catalyst to overcome the low reactivity and control the regioselectivity and the enantiotopic face selection. Phthalimide serves as the amination agent, which could be readily removed to afford a primary amine. This coordination assistance enables hydroamination to occur selectively at the remote position with up to 97 % ee, delivering valuable enantio‐enriched γ‐amino acid derivatives that are otherwise challenging to access.
Chemocatalytic Conversion of Dinitrogen to Ammonia Mediated by a Tungsten Complex
Authors: Vogt Anna‐Marlene , Engesser Tobias A. , Krahmer Jan , Michaelis Niels , Pfeil Mareike , Junge Jannik , Näther Christian , Le Poul Nicolas , Tuczek Felix
Published: December 2024

Whereas molybdenum dinitrogen complexes have played a major role as catalytic model systems of nitrogenase, corresponding tungsten complexes were in most cases found to be catalytically inactive. Herein, we present a modified pentadentate tetrapodal (pentaPod) phosphine ligand in which two dimethylphosphine groups of the pentaPodMe (P5Me) ligand have been replaced with phospholanes (Pln). The derived molybdenum complex [Mo(N2)P5Pln] generates 22 and the analogous tungsten complex [W(N2)P5Pln] 7 equivalents of NH3 from N2 in the presence of 180 equivalents of SmI2(THF)2/H2O, rendering the latter the first tungsten complex chemocatalytically converting N2 to NH3. In contrast, the tungsten complex [W(N2)P5Me] generates ammonia from N2 only in a slightly overstoichiometric fashion. The reasons for these reactivity differences are investigated with the help of spectroscopic and electrochemical methods.
Fluoromethyl Triflate and Fluoromethyl Fluorosulfonate: Easily Accessible and Powerful Fluoromethylation Reagents
Authors: Gisnapp Alexander , Trapp Pia C. , Schwabedissen Jan , Stammler Hans‐Georg , Reichel Marco , Leitz Dominik , Krumm Burkhard , Karaghiosoff Konstantin , Mitzel Norbert W.
Published: December 2024

Fluoromethyl triflate (superfluoromethyl, SFM, FH2COSO2CF3) and fluoromethyl fluorosulfonate (magic fluoromethyl, MFM, FH2COSO2F) are two easily synthesized, highly effective and non‐ozone depleting fluoromethylation reagents. They are analogous to the well‐known and widely used methylation reagents H3COSO2CF3 and H3COSO2F. Both SFM and MFM have been fully characterized by multinuclear NMR spectroscopy (1H, 13C, 17O, 19F, 33S). Their structures have been determined in the solid state on in situ grown crystals by X‐ray diffraction and in the gas phase by electron diffraction. The fluoromethylation efficiency of SFM and MFM was shown by reactions with chalcogen nucleophiles of differing nucleophilicity. All fluoromethylated products were isolated as pure compounds and characterized by NMR and vibrational spectroscopy, as well as in some cases by single crystal X‐ray diffraction.
Changes in phytochemicals, antioxidant activities, and oxidative stability of oil from germinated peanuts
Authors: Huh Moon Haeng , Lee Junsoo , Lee Hana
Published: December 2024

Germination is a promising technique for enhancing the nutritional and functional properties of seeds. Among the nuts, peanuts are composed of approximately 50% oil, which is abundant in unsaturated fatty acids, tocopherols, and phytosterols. This study investigated the changes in phytochemical profile, antioxidant capacity, and oxidative stability of oil from germinated peanuts. Peanuts were germinated over 0, 2, 4, 6, and 8 days. The oil from germinated peanuts exhibited increased levels of α‐tocopherol, phytosterols, and carotenoids, while the γ‐tocopherol, oleic acid, and linoleic acid levels were reduced. Notably, the oil from germinated peanuts at Day 8 exhibited substantially improved antioxidant activity and oxidative stability compared with oil from ungerminated peanuts. These enhancements were attributed to the elevated phytochemical content of the peanut oil resulting from germination. These results highlight that germination of peanut seeds is an effective strategy for enhancing peanut oil's phytochemical content and oxidative stability, thereby presenting potential benefits for health‐conscious consumers.
Multichromophoric Triad and g‐C3N4 Composite as Efficient Heterogeneous Photocatalyst for Oxidative Amidation of Aldehydes
Authors: Kumari Anita , Sekhar Roy Raj , Gautam Ujjal K. , Sengupta Sanchita
Published: December 2024

In this work, we have synthesized a multichromophoric light‐harvesting antenna, namely, triad, consisting of naphthalene monoimide (NMI) and perylene monoimide (PMI) chromophores. Triad was adsorbed onto polymeric graphitic carbon nitride (g‐C3N4) to form triad/g‐C3N4 composite, utilized as a photocatalyst for oxidative amidation reaction. This composite photocatalyst demonstrated enhanced photocatalytic activity for the conversion of a variety of aldehydes to amides, leading up to 82 % product yield compared to only g‐C3N4 or only triad as photocatalysts. This study highlights the potential of heterogeneous photocatalyst based on metal‐free multichromophoric systems for visible‐light‐driven amide bond formation through an environmentally benign approach.
Lithium in drinking water: Review of chemistry, analytical methods, and treatment technologies
Authors: Korak Julie A. , Brandhuber Philip J. , Goodwill Joseph E.
Published: December 2024

Lithium was included in the fifth Unregulated Contaminants Monitoring Rule, signaling the Environmental Protection Agency's interest in regulating lithium. Many questions regarding occurrence, health effects, and treatability of lithium exist. This review primarily focuses on the relationship between lithium chemistry and treatability. Sampling indicates nationwide lithium occurrence in drinking water. Yet, lithium is not included in the Integrated Risk Information System, reflecting a lack of censuses regarding its health effects. Aqueous lithium is a monovalent cation with size, charge density, and solubility properties that present treatment challenges. Lithium's growing economic value is stimulating new extraction and isolation technologies, but these may not be transferable to drinking water treatment. Currently, reverse osmosis is the only full‐scale drinking water treatment technology that can reliably remove significant levels (>50%) of lithium. Focusing future research efforts on electrodialysis and inorganic ion sieves may yield significant gains in effectiveness and readiness for the drinking water industry.
Integrative computational pipeline for identifying binding‐enhancing mutations targeting the MBD2–p66α interaction: Implications for therapeutic applications
Authors: Mazraedoost Sargol , Malekroodi Hadi Sedigh , Yi Myunggi , Liu J. Jay , In Lim Sung
Published: December 2024

This study presents a comprehensive computational pipeline to identify and evaluate potential stabilizing mutations for the coiled‐coil protein–protein interaction between methyl‐CpG‐binding domain protein 2 (MBD2) and transcriptional repressor p66‐alpha (p66α). The pipeline begins with the BeAtMuSiC program, which employs statistical potentials derived from known structures to predict candidate stabilizing mutations at the protein–protein interface. Out of 565 potential mutations, 10 single‐point mutations (K149I, K163I, A237F, K149L, K149M, K163L, R166M, R166W, K163F, and E155L) with the highest binding affinity were selected for further evaluation using rigorous alchemical free energy calculations. These alchemical simulations conducted using the double‐system/single‐box method, predicted changes in binding free energy (ΔΔG) upon mutation while maintaining charge neutrality. The Crooks–Gaussian intersection technique was employed to analyze the results, identifying K149I, K149L, and K163L as potentially enhancing binding affinity the most, while mutations like K163F, A237F, and E155L were predicted to destabilize the interaction significantly. Complementary conventional Molecular Dynamics Simulations provided further support for the alchemical predictions, revealing decreased flexibility, increased contacts, and more compact structures for the predicted stabilizing mutants compared with the wild‐type complex. Additionally, Molecular Mechanics Poisson–Boltzmann Surface Area (MM/PBSA) binding free energy calculations were performed, and their results were consistent with the direction of free energy change predicted by the alchemical approach. This multifaceted computational pipeline, combining predictive methods, alchemical simulations, and conventional analyses, offers valuable insights into modulating the binding affinity of the MBD2–p66α coiled‐coil interaction. The identified stabilizing mutations can create numerous opportunities across biotechnology, biomedical research, and synthetic biology.
Baihui‐Penetrating‐Qubin Acupuncture Attenuates Neurological Deficits Through SIRT1/FOXO1 Reducing Oxidative Stress and Neuronal Apoptosis in Intracerebral Hemorrhage Rats
Authors: Dong Shan‐Shan , Li Ming‐Yue , Yu Xue‐Ping , Kan Yu‐Na , Dai Xiao‐Hong , Zheng Lei , Cao Hong‐tao , Duan Wen‐Hui , Luo En‐Li , Zou Wei
Published: December 2024

Background

Intracerebral hemorrhage (ICH) is a significant global disease with high mortality and disability. As of now, there is no effective therapy available. Oxidative stress and neuronal apoptosis play essential roles in ICH, determining neuronal survival. In our preliminary studies, we found that Baihui‐penetrating‐Qubin acupuncture could improve neurological deficits and neuropathological damage in the perihematomal area in ICH rats. The SIRT1/FOXO1 signaling pathway has been reported to mediate antioxidant and anti‐neuronal apoptosis. This study aimed to investigate the effects of Baihui‐penetrating‐Qubin acupuncture on oxidative stress and neuronal apoptosis after ICH and the role of SIRT1/FOXO1 in acupuncture's neuroprotection.

Methods

ICH rat models were established by autologous tail blood (50 µL) infusion into the caudate nucleus. EX527, SIRT1‐specific inhibitor was intraperitoneally administered 3 days before ICH. Baihui‐penetrating‐Qubin acupuncture treatment was performed once a day for 30 min after ICH. Neurological deficits were evaluated using the modified neurological severity score (mNSS). Brain edema was evaluated using brain water content. HE staining and Nissl staining were used to evaluate neuropathological damage in the perihematomal area. Terminal deoxynucleotidyl transferase dUTP nick end labeling was used to quantify neuronal apoptosis. Specific kits were used to detect the levels of SOD, CAT, GSH‐Px in the brain. The oxidative DNA damage was evaluated using enzyme‐linked immunosorbent assay to detect the level of 8‐hydroxyguanosine (8‐OHdG). Western blot was used to evaluate the expressions of SIRT1, Ac‐FOXO1, FOXO1, Bcl‐2, and Bax. Immunofluorescence staining was conducted to detect the cellular localization of SIRT1.

Results

Baihui‐penetrating‐Qubin acupuncture improved the neurological deficits and brain edema, reduced the pathological injury and neuronal degeneration in 3 days in the perihematomal area after ICH. Mechanistically, acupuncture reduced oxidative stress injury and neuronal apoptosis via activating SIRT1/FOXO1 pathway. The neuroprotective effects of acupuncture were abolished by injection of the SIRT1 inhibitor EX527.

Conclusions

Baihui‐penetrating‐Qubin acupuncture could reduce oxidative stress and neuronal apoptosis, at least in part, through the SIRT1/FOXO1 signaling pathway, improving neurological deficits and neuropathological damage after ICH. These findings suggest that Baihui‐penetrating‐Qubin acupuncture is an effective therapy for ICH, as well as targeting SIRT1 signaling to promote neuron survival could be a potential therapeutic strategy.
Derivative Technologies of Expansion Microscopy and Applications in Biomedicine
Authors: Jia Dongling , Cui Minhui , Divsalar Adeleh , Khattab Tawfik A. , Al‐Qahtani Salhah D. , Cheung Edwin , Ding Xianting
Published: December 2024

Expansion microscopy (ExM) is an innovative super‐resolution imaging technique that utilizes physical expansion to magnify biological samples, facilitating the visualization of cellular structures that are challenging to observe using traditional optical microscopes. The fundamental principle of ExM revolves around employing a specialized hydrogel to uniformly expand biological samples, thereby achieving super‐resolution imaging under conventional optical imaging conditions. This technology finds application not only in various biological samples such as cells and tissue sections, but also enables super‐resolution imaging of large biological molecules including proteins, nucleic acids, and metabolite molecules. In recent years, numerous researchers have delved into ExM, resulting in the continuous development of a range of derivative technologies that optimize experimental protocols and broaden practical application fields. This article presents a comprehensive review of these derivative technologies, highlighting the utilization of ExM for anchoring nucleic acids, proteins, and other biological molecules, as well as its applications in biomedicine. Furthermore, this review offers insights into the future development prospects of ExM technology.
High Catalytic Activity of Yttria‐Stabilized Zirconia‐Supported Gold Nanoparticles for Hydrogen Peroxide Production from Oxygen and Formic Acid Under Ambient Conditions
Authors: Teranishi Miwako , Naya Shin‐ichi , Tanaka Senku , Kobayashi Hisayoshi , Tada Hiroaki
Published: December 2024

Hydrogen peroxide (H2O2) is an important chemical widely used in the industry. Recently, insulating zirconia‐supported Au nanoparticles (NPs) prepared by a modified deposition precipitation method (Au/ZrO2‐MDP) have been reported to show catalytic activity for H2O2 production from aerated HCOOH aqueous solution much higher than Au/n‐type semiconducting metal oxides (Au/n‐MOs) prepared by the normal deposition precipitation method. In this study, we report that Au/yttria‐stabilized zirconia (Au/YSZ‐MDP) exhibits catalytic activity for the reaction far exceeding those of Au/n‐MOs and even Au/ZrO2‐MDP. Au/YSZ‐MDP yields H2O2 from the aerated 1.06 M HCOOH aqueous solution with an initial rate of 2.2 mmol h−1 gcat−1, and a turnover frequency (TOF) of 4.3 × 102 h−1 at 25 °C. X‐ray photoelectron and photoluminescence spectral data, in addition to the effect of YSZ surface modification with an aluminum oxide, indicate that the remarkable catalytic activity of Au/YSZ‐MDP is induced by the oxygen vacancies (Ov) and Ov‐derived Zr─OH groups on the YSZ surface in the vicinity of Au NPs.
Translational Medicine in Alzheimer's Disease: The Journey of Donanemab From Discovery to Clinical Application
Authors: Jayaprakash Nandhini , Elumalai Karthikeyan
Published: December 2024

Substantial research has been conducted to identify an efficient treatment for Alzheimer's disease (AD). Existing treatments, including cholinesterase inhibitors and N‐methyl D‐aspartate (NMDA) receptor antagonists, do not reverse or slow the disease course but only treat its manifestations. This limitation has brought attention to the need for treatments that modify the amyloid‐beta (Aβ) and tau pathology of the disease. One recent advancement in AD treatment is donanemab, a monoclonal antibody intended to clear Aβ plaques in the brain. It targets pyroglutamyl(3)‐Aβ protein (3–42) to remove Aβ deposits and alter the disease course. This review explores the timeline of donanemab use from discovery to clinical use. The pharmacodynamics and pharmacokinetics of the drug are discussed along with typical and suboptimal preclinical and clinical trial results in terms of efficacy, safety, and tolerability. Thus, donanemab is more effective than donepezil and rivastigmine in removing plaques and improving cognition. At the same time, it is not devoid of safety concerns that are typical of the majority of amyloid‐targeted medicines. The control to end the treatment after plaque cleaning is a unique selling point for some patients, making it more attractive. The innovation and development of donanemab from research to clinical practice are a clear representation of the role of the field of translational medicine in the practical application of new knowledge in the treatment of AD.
C(sp2)−H Acylation of Benzo[h]quinolines at Room Temperature via Aldehyde Autoxidation and Palladium Catalysis Cooperation
Authors: Roy Ishita , Mandal Nilangshu , Biswas Promita , Datta Ayan , Guin Joyram
Published: December 2024

Herein, we report Pd‐catalyzed C(sp2)−H acylation using aldehyde as acyl source and O2 as the green oxidant at room temperature. A selective association of acyl radical formed in‐situ during aldehyde autoxidation with Pd‐catalysis is the key to the process. The reaction afforded products in good yields (up to 82 %) and it is scalable. The proposed PdII/PdIII‐catalytic cycle is supported by a series of control studies and DFT calculations.
Helical Supramolecular Polymers Formed via Head‐to‐Tail Host‐Guest Complexation of Chiral Bisporphyrin Monomers with Trinitrofluorenone
Authors: Hisano Naoyuki , Kodama Tomoki , Koya Soichiro , Haino Takeharu
Published: December 2024

The intermolecular host‐guest complexation of head‐to‐tail monomers consisting of cleft‐shaped bisporphyrin and trinitrofluorenone units connected by a chiral binaphthyl linker was employed to construct helically twisted supramolecular polymers. Results from 1H NMR, diffusion‐ordered NMR spectroscopy, and viscometry experiments revealed that the supramolecular polymerization of these monomers follows a ring‐chain competition mechanism. The introduction of bulky substituents at the linker significantly suppressed the formation of macrocyclic oligomers, whereas smaller alkyl chains facilitated the formation of the cyclic form. The chirally twisted structures of the supramolecular polymers were confirmed using circular dichroism spectroscopy. Atomic force microscopy revealed that the (R)‐ and (S)‐configurations of the binaphthyl linkers induced right‐ and left‐handed helical structures, respectively, in the supramolecular polymer chains. The absence of cooperativity in the supramolecular copolymerization of (R)‐ and (S)‐1a resulted in the formation of stereo‐random supramolecular copolymers.
Toward Global Sediment Management: Lessons Learned From a Multidimensional Risk Assessment
Authors: Rađenović Dunja , Slijepčević Nataša , Tomić Tanja , Tenodi Slaven , Krčmar Dejan , Beljin Jelena , Tomašević Pilipović Dragana
Published: December 2024

Sediment from the Serbian Great Bačka Canal (GBC), which has long been classified as toxic waste due to high pollutant concentrations, exemplifies the sediment management challenges in Europe, where regulations vary by country. Serbian legislation primarily focuses on total metal concentrations relative to prescribed limits. Our study addresses this limitation by using an integrated approach to assess sediment pollution's detrimental effects at the ecosystem level. This approach is particularly relevant for the GBC, an environmental hotspot historically impacted by severe pollution from untreated industrial wastewater and population growth. Although previous research on the GBC has predominantly focused on chemical analyses, often overlooking broader environmental and health impacts, our study aims to evaluate whether ecotoxicological tests provide a more comprehensive assessment of sediment quality compared to traditional methods. Although only copper concentrations surpassed national limits, multiple metals and polycyclic aromatic hydrocarbons (PAHs) exceeded international sediment quality guidelines (SQGs). Sequential extraction revealed that 50% of copper was immobilized in the residual fraction, and ecotoxicological tests with Myriophyllum aquaticum indicated potential toxicity. Human health risk assessments showed a low risk of carcinogenic effects from PAHs, but a higher risk associated with zinc and copper. These findings highlight the urgent need for pollution reduction and ecological restoration in the GBC and similar river systems.
Prevalence Estimates of Cytochrome P450 Phenoconversion in Youth Receiving Pharmacotherapy for Mental Health Conditions
Authors: Gerlach Samuel , Maruf Abdullah Al , Shaheen Sarker M. , McCloud Ryden , Heintz Madison , McAusland Laina , Arnold Paul D. , Bousman Chad A.
Published: December 2024

Pharmacogenetics‐predicted drug metabolism may not match clinically observed metabolism due to a phenomenon known as phenoconversion. Phenoconversion can occur when an inhibitor or inducer of a drug‐metabolizing enzyme is present. Although estimates of phenoconversion in adult populations are available, prevalence estimates in youth populations are limited. To address this gap, we estimated the prevalence of phenoconversion in 1281 youth (6–24 years) receiving pharmacotherapy for mental health conditions and who had pharmacogenetics testing completed for four genes (CYP2B6, CYP2C19, CYP2D6, CYP3A4). Self‐reported medication and cannabidiol/cannabis use were collected at the time of pharmacogenetics testing. Nearly, half (46%) of the cohort was estimated to be phenoconverted for one of the four genes examined. Comparison of metabolizer phenotype frequencies before and after adjustment for phenoconversion showed significantly more youth had actionable phenotypes for CYP2C19 (60.3% vs. 69.1%; P =< 0.001), CYP2D6 (49.3% vs. 63.0%; P =< 0.001), and CYP3A4 (8.5% vs.12.2%; P = 0.003) after phenoconversion adjustment. Of youth who were phenoconverted, 24% had a change in their metabolizer phenotype that would lead to current pharmacogenetics‐based prescribing guidelines recommending a change to standard prescribing (dose adjustment, alternative medication). Our findings indicate a high prevalence of cytochrome P450 phenoconversion among youth receiving pharmacotherapy for mental health conditions. Adjustment for phenoconversion should be considered when implementing pharmacogenetics testing in youth populations to improve the clinical utility of this testing in practice.
Chief Executive Officer Narcissism and Environmental, Social, and Governance Performance: The Moderating Role of Chief Executive Officer Gender
Authors: Effah Nana Adwoa Anokye , Wang Qinggang , Su Kun
Published: December 2024

This study explores the influence of Chief Executive Officer (CEO) narcissism on the environmental, social, and governance (ESG) performance of listed firms on the Johannesburg stock market (JSE). Using hand‐collected data from annual reports and ESG rating data from the CSRHub dataset, we conducted empirical analyses for 81 firms from 2014 to 2022. As the first study to assess CEO narcissism using a validated unobtrusive measure in the South African market, the Driscoll and Kraay approach of panel corrected standard errors was employed in the main analysis, while the two‐stage least squares (2SLS) model was used for robustness. Results revealed that there is a negative and significant relationship between CEO narcissism and ESG performance. Moreover, CEO gender positively moderates the negative relationship between CEO narcissism and ESG performance. The results provide a meaningful empirical addition to the upper echelons literature by delineating the implications of the dark sides of narcissism for management, regulators, and policymakers.
Resource Allocation of Device‐To‐Device–Enabled Millimeter‐Wave Communication: A Deep Reinforcement Learning Approach
Authors: Md Bilal N. , Velmurugan T.
Published: December 2024

Device‐to‐device (D2D) communication is a promising development in 5G networks, offering potential benefits such as increased data rates, reduced costs and latency, and improved energy efficiency (EE). This study analyzes the operation of millimeter‐wave (mmWave) in cellular networks. A client's device can establish a connection to either a base station or another client, facilitating D2D communication based on a distance threshold and accounting for interference. The research employs a deep reinforcement learning (DRL)–based resource allocation (RA) scheme for D2D‐enabled mmWave communications underlaying cellular networks. It evaluates the effectiveness of several metrics: coverage probability, area spectral efficiency, and network EE. Among networks limited by noise, the proposed strategy demonstrates the highest coverage probability performance. The paper also suggests an optimization approach based on the firefly algorithm for RA, taking into account the stochastic nature of wireless channels. An asynchronous advantage actor–critic (A3C) DRL algorithm is modeled for this purpose. The performance of the proposed scheme is compared with two existing algorithms: soft actor–critic and proximal policy optimization. Overall, the numerical results indicate that our proposed firefly algorithm–optimized A3C method outperforms the other analytical methods.
How Important Is Informed Natal Dispersal for Modelling the Demographic and Genetic Effects of Environmental Variability?
Authors: Banks Sam C. , Davies Ian D. , Cremona Teigan , Davies Hugh F. , Carey Alexander R. , Cary Geoffrey J.
Published: December 2024

Dispersal is a fundamental ecological process that influences population dynamics and genetic diversity and is therefore an important component of the models used to simulate population responses to environmental change. We considered informed dispersal in relation to settlement location, where individuals could optimise selection of settlement location with regard to per capita resource availability and investigated the importance of this type of informed dispersal for simulated demography and genetic diversity under different biological and environmental scenarios. We used an individual‐based simulation model scaled with reference to the ecology of small mammals in fire prone savanna ecosystems. We simulated demographic and genetic processes under informed and uninformed dispersal across several scenarios of life history, environmental heterogeneity (patch size and patch dynamics) and dispersal distance. The effect of the dispersal method on population size far outweighed that of dispersal distance under all combinations of habitat quality, temporal dynamics, patch size and dispersal distance modelled. The effects of habitat patch size and habitat dynamics (representing temporal change in habitat quality such as that potentially generated by disturbance) were low under most of the scenarios modelled. Informed dispersal influenced genetic diversity and differentiation, but the effects were weaker than those of dispersal distance. The genetic effect of informed dispersal occurred through the effect on genetic diversity of the overall metapopulation, while the dispersal distance influenced gene flow and genetic diversity within subpopulations. Informed dispersal was less effective in increasing population size in models of a long‐lived species with overlapping generations. This was particularly true when habitat quality was dynamic and natal dispersal choices did not result in lifelong habitat quality outcomes. Our results suggest that including informed decision‐making in dispersal in simulation models leads to different projections of demography, genetic diversity and susceptibility to environmental change.
Ecosystem Size Mediates the Effects of Resource Flows on Species Diversity and Ecosystem Function at Different Scales
Authors: Giacomuzzo Emanuele , Peller Tianna , Gounand Isabelle , Altermatt Florian
Published: December 2024

Ecosystem size and spatial resource flows are key factors driving species diversity and ecosystem function. However, the question of whether and how these drivers interact has been largely overlooked. Here, we investigated how ecosystem size asymmetry affects species diversity and function of two‐patch meta‐ecosystems connected through flows of nonliving resources. We conducted a microcosm experiment, mimicking resource flows between ecosystems of different sizes yet otherwise identical properties or between ecosystems of the same size. Meta‐ecosystems with asymmetric ecosystem sizes displayed higher α‐diversity but lower β‐diversity and ecosystem function (total biomass) than their unconnected counterparts. At the same time, such an effect was not found for meta‐ecosystems of identical patch sizes. Our work demonstrates how the size of ecosystems, interconnected via resource flows, can modulate cross‐ecosystem dynamics, having implications for species diversity and function across scales.
Positive Selection of TLR2 and MyD88 Genes Provides Insights Into the Molecular Basis of Immunological Adaptation in Amphibians
Authors: Zhang Jie , Zhao Ruinan , Bi Hongyan , He Jiaoying , Guo Yang , Liu Dian , Yang Ganggang , Chen Xiaohong , Chen Zhuo
Published: December 2024

The transition from water to land of amphibians is evolutionarily significant in the history of vertebrates, and immunological adaptation is an important challenge for amphibians to respond to the dramatic changes of the environmental pathogens during their origin and diversification. Toll‐like receptors (TLRs) are important pattern recognition receptors for the innate immune response and TLRs signaling pathway play essential roles in the immune responses to pathogens and inflammatory reaction. However, the evolutionary patterns and molecular mechanisms underlying their adaptation in amphibians are poorly documented to date. Here, we determined the coding regions, expression patterns of TLR2 and Myeloid differentiation factor 88 (MyD88) in the large treefrog (Zhangixalus dennysi), and explored the evolutionary patterns of these two genes in amphibians. Quantitative Real‐time PCR analyses showed that the TLR2 and MyD88 mRNA were expressed in all the organs/tissues examined, both with the highest levels in the heart and the lowest levels in the body fat for TLR2 and lung for MyD88. The highly conservation and functional significance of these two genes in amphibians were supported based on the sequence characteristics and evolutionary analyses. Significantly positive selection was found to be acting on TLR2 and MyD88 in amphibians based on different site models. Strong signal of positive selection among different amphibian lineages for these two genes was also detected and a series of positively selected sites were identified based on the branch‐site analysis. Our results suggest that amphibians have adapted to different pathogenic microorganisms during their transition from the aquatic to terrestrial environment and diversification into various habitats. The present study will provide new insights into the evolutionary process and molecular basis underlying the immunological adaptation in vertebrates.
Breeding bird response to adaptive multi‐paddock and continuous grazing practices in Southeastern United States
Authors: McGraw Michael J. , Apfelbaum Steven I. , Thompson Ry , Wang Fugui , Szuter Michael A. , Teague Richard , Byck Peter , Conser Russ
Published: December 2024

Grassland bird populations are declining steeply, reflecting the degradation and loss of native grassland habitats. To assess how grazing management affects declining grassland bird populations, we compared breeding avifaunal communities in adaptive multi‐paddock (AMP) grazed and continuously grazed (CG) pastures in the Southeastern United States. AMP grazing involves alternating very short grazing periods at high animal densities with prolonged recovery periods across many small paddocks. Both the AMP and CG paddocks attracted obligate grassland birds during the breeding season; however, AMP‐grazed paddocks supported significantly higher detection of four obligate grassland breeding bird species. We used distance sampling techniques to account for differences in detectability for each species. The resulting densities for the grassland guild and Eastern Meadowlark as a species both revealed significantly higher densities within the AMP versus CG paddocks. Despite significantly more unadjusted detections of confirmed breeding ecotonal species, such as Blue Grosbeak, Eastern Bluebird, Brown Thrasher, Yellow‐breasted Chat, Eastern Towhee, Loggerhead Shrike, and Field Sparrow in AMP versus CG paddocks, no significant difference was found in the ecotonal guild after adjusting densities using effective detection radii. The CG paddocks supported fewer obligate grassland and ecotonal birds, with some exceptions (e.g., higher adjusted density of Eastern Bluebirds in CG) but supported comparable overall bird species richness. AMP grazing practices offer a viable strategy for increasing the diversity and abundance of obligate grassland and ecotonal breeding birds within existing cattle‐grazed landscapes in the Southeastern United States.
Historical dynamics of marginal populations at the leading edge of a temperate species in the boreal‐temperate ecotone
Authors: Mondou Laperrière Pierre‐Yves , Minchev Todor S. , Grondin Pierre , Lavoie Martin , de Lafontaine Guillaume
Published: December 2024

Marginal populations of temperate species at the leading edge of their range will likely play a key role at the boreal‐temperate ecotone (BTE) in the face of climate changes. In eastern North America, red maple (Acer rubrum L.) is the most abundant temperate tree species encroaching into the boreal forest. In order to provide useful insights about possible responses to climate change and anticipate the formation of new assemblages, this study relies on long‐term Holocene data from forest soil wood macrofossils (charcoal and ligneous remains) and contemporary stand analyses to assess the postglacial origin and modern‐day dynamics of red maple at its leading edge within the BTE. We sampled the soils of eight marginal red maple stands. Macroscopic charcoal particles and ligneous remains were identified using microanatomical characteristics. Macrofossils of temperate tree species were radiocarbon dated to reconstruct their long‐term stand‐scale history. Contemporary dynamics (<200 years) were assessed by analyzing tree size structure of all stems within 400 m2 plots, minimal stand age from tree‐ring dating, as well as the recent occurrence of fire and logging from published ecoforest data. White pine (Pinus strobus L.), the only other temperate tree species that was identified, was present 6500–4000 years ago, during the mid‐Holocene thermal maximum but decreased during the cooler and fire‐prone late‐Holocene Neoglacial (4000 years ago to present). By contrast, red maple was found at its current northern limit since the last 4000 years. Modern‐day marginal red maple stands are self‐regenerating populations that established following a recent stand‐replacing disturbance (wildfire or clearcut). The present‐day increase of anthropogenic disturbances within the BTE could mirror the Neoglacial increase in fire activity that fostered red maple during the Holocene. We thus predict that red maple is poised to increase in abundance within the BTE, which should facilitate the northward establishment of other temperate deciduous species into the boreal forest prompted by the new conditions brought about by anthropogenic or climate change‐induced disturbances.
Same money, different impact? The curving effect of European Structural and Investment Funds on EU support in Spain (1990–2019)
Authors: Cantó Joel , Baraibar Javier , Arregui Javier
Published: December 2024

European Structural and Investment Funds (ESIF) engender European Union (EU) support in generating economic growth, but their effect is conditional on individual European identity and educational background. This study investigates whether the positive impact of ESIF spending on EU attitudes also depends on the alignment of funding with the economic needs of recipient regions. We examine this issue with the Spanish case (1990–2019), employing a unique combined data set of Eurobarometer waves and regional NUTS‐2 economic indicators. Our findings indicate that EU funds manage to decrease Euroscepticism only in laggard regions, which receive the lion's share of funds and allocate them to public goods easily perceived and communicated to the local population. Conversely, the effect of ESIF on transforming attitudes is absent in middle and high‐income regions. The findings suggest a more complicated relationship between ESIF and EU support, which necessitates taking both individual and contextual factors into account.
New insights into the thermo‐tectonic development of the Suez rift within the framework of the northern Arabian–Nubian Shield
Authors: Mansour Sherif , Hasebe Noriko , Glasmacher Ulrich A. , Tamura Akihiro , El‐Shafei Mohamed K.
Published: December 2024

The Gulf of Suez is a young continental rift, the flanks of which make up the Arabian–Nubian Shield basement complex that formed during the East African Orogeny. The impact and significance of the consecutive tectono‐thermal activities on the Arabian–Nubian Shield and the rifting processes in the Gulf of Suez remain uncertain. Combining zircon and apatite fission‐track dating with time–temperature modelling has been effective in addressing these issues. We here present thermochronological data for 20 basement samples collected from the Samra Mountain region at the northern tip of the Gulf of Suez's eastern flank. Zircon fission‐track data revealed two age groups separated spatially and dating from ca. 652 ± 25 Ma and ca. 426 ± 31 Ma. In contrast, apatite fission‐track data revealed three spatially separated age groups dating from ca. 473 ± 10 Ma, ca. 269 ± 29 Ma and ca. 101 ± 12 Ma. Reconstructed time–temperature historical records revealed four distinct rapid cooling pulses (i.e. Neoproterozoic, Devonian–Carboniferous, Cretaceous and Oligocene–Miocene) consistent with the tectonic history and regional geology. By integrating our findings with the regional tectonic and sedimentation histories, the relationship between cooling events and exhumation events could be inferred. These cooling pulses were activated in response to four events: (1) the Precambrian–Cambrian post‐accretion erosional event, (2) the Devonian–Carboniferous Variscan tectonic event, (3) the Cretaceous Gondwana disintegration and (4) the Oligocene–Miocene Gulf of Suez rifting, respectively. In the studied region, no thermal overprint was seen in association with the rifting in the Gulf of Suez, suggesting that the region had been segmented into northern and southern segments. A southward thermal source, the Arabian margin plume, caused an increase in the rift flank elevation and heat flow in the southern Sinai.
Definitions matter: Multicenter investigation of incidence and outcome of poor graft function after hematopoietic cell transplantation
Authors: Müskens Konradin F. , Collot‐d'Escury Winny N. R. , Dandis Rana , Haitjema Saskia , Kuball Jürgen , de Witte Moniek A. , Bierings Marc , Lindemans Caroline A. , Nierkens Stefan , Belderbos Mirjam E.
Published: December 2024

Despite advances in allogeneic hematopoietic cell transplantation (HCT), poor graft function (PGF) remains an important complication with substantial morbidity and mortality. The investigation of preventive and therapeutic PGF treatments is hindered by inconsistencies in reported incidence and outcomes across studies, which may be explained by heterogeneity in PGF definition. To assess the impact of definition heterogeneity, we conducted a multicenter study, analyzing over 35.000 longitudinal blood counts from 427 pediatric and 405 adult HCT recipients. We compared the incidence, risk factors, and outcome of PGF, based on the three most common definitions. We identified 97 pediatric and 75 adult HCT recipients fulfilling at least one PGF definition. The 2‐year cumulative incidence of PGF varied significantly depending on the definition used, ranging from 6.8% to 20% in children and 4.9% to 18% in adults. Two‐year mortality for PGF patients ranged from 33% to 40% in children and 46% to 65% in adults. Notably, PGF patients identified solely by lenient definitions had similar mortality to HCT recipients with good graft function. Risk factors for PGF also varied by definition in both cohorts, and included older recipient age and cord blood transplantation. In conclusion, our study demonstrates that differences in PGF definition significantly impact the reported incidence, risk factors, and outcome. This underscores the need to harmonize PGF definitions across scientific studies, clinical practice, and transplant registries. Future studies, using standardized, quantitative thresholds for PGF, are required to determine optimal treatment strategies for both mild and severe forms of PGF.
Proliferating CLL cells express high levels of CXCR4 and CD5
Authors: Friedman Daniel , Mehtani Drshika P. , Vidler Jennifer B. , Patten Piers E. M. , Hoogeboom Robbert
Published: December 2024

Chronic lymphocytic leukemia (CLL) is an incurable progressive malignancy of CD5+ B cells with a birth rate between 0.1% and 1% of the entire clone per day. However, the phenotype and functional characteristics of proliferating CLL cells remain incompletely understood. Here, we stained peripheral blood CLL cells for ki67 and DNA content and found that CLL cells in G1‐phase have a CXCR4loCD5hi phenotype, while CLL cells in S/G2/M‐phase express high levels of both CXCR4 and CD5. Induction of proliferation in vitro using CD40L stimulation results in high ki67 levels in CXCR4loCD5hi cells with CXCR4 expression increasing as CLL cells progress through S and G2/M‐phases, while CXCR4hiCD5lo CLL cells remained quiescent. Dye dilution experiments revealed an accumulation of Ki67hi‐divided cells in the CXCR4hiCD5hi fraction. In Eµ‐TCL1 transgenic mice, the CXCR4hiCD5hi fraction expressed high levels of ki67 and was expanded in enlarged spleens of diseased animals. Human peripheral blood CXCR4hiCD5hi CLL cells express increased levels of IgM and the chemokine receptors CCR7 and CXCR5 and migrate efficiently toward CCL21. We found higher levels of CXCR4 in patients with progressive disease and the CXCR4hiCD5hi fraction was expanded upon clinical relapse. Thus, this study defines the phenotype and functional characteristics of dividing CLL cells identifying a novel subclonal population that underlies CLL pathogenesis and may drive clinical outcomes.
Post‐CAR T‐Cell Therapy Failure Metabolic Parameters Predict Survival and Response in Large B‐Cell Lymphoma
Authors: Ababneh Hazim S. , Frigault Matthew J. , Ng Andrea K. , Patel Chirayu G.
Published: December 2024

18F‐fluorodeoxyglucose positron emission tomography‐computed tomography (18F‐FDG PET/CT) parameters have shown a significant prognostic role in relapsed/refractory large B‐cell lymphoma (LBCL) patients undergoing CD19‐targeted chimeric antigen receptor (CAR) T‐cell therapy. While a substantial body of evidence exists on the prognostic value of PET/CT parameters in peri‐CAR T setting, data available on the prognostic value of PET/CT parameters following CAR T‐cell therapy failure is lacking. Therefore, we sought to analyze the PET/CT scans of LBCL patients who experienced post‐CAR T relapsed/progressive disease and subsequently received salvage therapies. Thirty‐three LBCL patients who had PET‐CT scans done demonstrating post‐CAR T failure and then received salvage therapies [as a first salvage modality: RT alone, nine patients; combined modality therapy (CMT), seven patients; systemic therapy (ST) alone, 17 patients] were analyzed. The median follow‐up after CAR T‐cell infusion was 11.7 months [interquartile range (IQR): 5.1–24.4 months], and the median follow‐up after post‐CAR T salvage therapy was 7.3 months (IQR: 2.7–19.1 months). The median timeframe for the PET scan showing post‐CAR T failure was 2.4 months (IQR: 0.96–5.0 months). On univariable analysis from salvage therapy start date, high metabolic tumor volume (MTV) and total lesion glycolysis (TLG) were associated with inferior overall survival (OS) (Hazard ratio –HR = 8.4, p < 0.0001; HR = 3.2, p = 0.01, respectively). High MTV was associated with a non‐significant trend of inferior progression‐free survival (PFS) (HR = 3.5, p = 0.09). High maximum standardized uptake value (SUVmax) was not associated with inferior OS or inferior PFS. On multivariable analysis from salvage therapy start date, high MTV (HR = 4.6, 95% CI: 1.5–14.3, p = 0.009) was identified to be an independent prognostic factor for inferior OS. High International Prognostic Index (IPI) (≥ 3) at the time of salvage therapy (HR = 2.5, 95% CI: 1.1–5.6, p = 0.02) was significantly associated with inferior PFS. Our study shows that semiquantitative PET/CT metrics, especially MTV, are significant prognostic indicators of overall survival in this highly refractory population after CAR T‐cell therapy failure, potentially refining prognostic and treatment approaches beyond conventional parameters like IPI.