bluuebunny/crossref_metadata_2025 huggingface dataset:
Anion‐Responsive Colorimetric and Fluorometric Red‐Shift in Triarylborane Derivatives: Dual Role of Phenazaborine as Lewis Acid and Electron Donor
Authors: Aota Nae , Nakagawa Riku , de Sousa Leonardo Evaristo , Tohnai Norimitsu , Minakata Satoshi , de Silva Piotr , Takeda Youhei
Published: April 2024

Photophysical modulation of triarylboranes (TABs) through Lewis acid‐base interactions is a fundamental approach for sensing anions. Yet, design principles for anion‐responsive TABs displaying significant red‐shift in absorption and photoluminescence (PL) have remained elusive. Herein, a new strategy for modulating the photophysical properties of TABs in a red‐shift mode has been presented, by using a nitrogen‐bridged triarylborane (1,4‐phenazaborine: PAzB) with a contradictory dual role as a Lewis acid and an electron donor. Following the strategy, PAzB derivatives connected with an electron‐deficient azaaromatic have been developed, and these compounds display a distinct red‐shift in their absorption and PL in response to an anion. Spectroscopic analyses and quantum chemical calculations have revealed the formation of a tetracoordinate borate upon the addition of fluoride, narrowing the HOMO–LUMO gap and enhancing the charge‐transfer character in the excited state. This approach has also been demonstrated in modulating the photophysical properties of solid‐state films.
One‐step Synthesis of Organic Terminal 2D Ti3C2Tx MXene Nanosheets by Etching of Ti3AlC2 in an Organic Lewis Acid Solvent
Authors: Wang Fei , Tian Feng , Xia Xuewen , Pang Zhongya , Wang Shujuan , Yu Xing , Li Guangshi , Zhao Yufeng , Xu Qian , Hu Shen , Ji Li , Zou Xingli , Lu Xionggang
Published: April 2024

The surface and interface chemistry are critical for controlling the properties of two‐dimensional transition metal carbides and nitrides (MXenes). Numerous efforts have been devoted to the functionalization of MXenes with small inorganic ligands; however, few etching methods have been reported on the direct bonding of organic groups to MXene surfaces. In this work, we demonstrated an efficient and rapid strategy for the direct synthesis of 2D Ti3C2Tx MXene nanosheets with organic terminal groups in an organic Lewis acid (trifluoromethanesulfonic acid) solvent, without introducing additional intercalations. The dissolution of aluminum and the subsequent in situ introduction of trifluoromethanesulfonic acid resulted in the extraction of Ti3C2Tx MXene (T=CF3SO3−) (denoted as CF3SO3H−Ti3C2Tx) flakes with sizes reaching 15 μm and high productivity (over 70 %) of monolayers or few layers. More importantly, the large CF3SO3H−Ti3C2Tx MXene nanosheets had high colloidal stability, making them promising as efficient electrocatalysts for the hydrogen evolution reaction.
High‐performance Pyroelectric Property Accompanied by Spin Crossover in a Single Crystal of Fe(II) Complex
Authors: Liu Chengdong , Li Yun , Tang Zheng , Gao Kai‐Ge , Xie Jing , Tao Jun , Yao Zi‐Shuo
Published: April 2024

Pyroelectric materials hold significant potential for energy harvesting, sensing, and imaging applications. However, achieving high‐performance pyroelectricity across a wide temperature range near room temperature remains a significant challenge. Herein, we demonstrate a single crystal of Fe(II) spin‐crossover compound shows remarkable pyroelectric properties accompanied by a thermally controlled spin transition. In this material, the uniaxial alignment of polar molecules results in a polarization of the lattice. As the molecular geometry is modulated during a gradual spin transition, the polar axis experiences a colossal thermal expansion with a coefficient of 796×10−6 K−1. Consequently, the material's polarization undergoes significant modulation as a secondary pyroelectric effect. The considerable shift in polarization (pyroelectric coefficient, p=3.7–22 nC K−1cm−2), coupled with a low dielectric constant (ϵ′=4.4–5.4) over a remarkably wide temperature range of 298 to 400 K, suggests this material is a high‐performance pyroelectric. The demonstration of pyroelectricity combined with magnetic switching in this study will inspire further investigations in the field of molecular electronics and magnetism.
Metal–Organic Framework‐Based Hetero‐Phase Nanostructure Photocatalysts with Molecular‐Scale Tunable Energy Levels
Authors: Yuan Kuo , Liu Zongyang , Yan Zhuang , Yun Qinbai , Song Tianqun , Guo Jun , Zhang Xiaotao , Zhong Dichang , Tang Zhiyong , Lu Tongbu , Hu Wenping
Published: April 2024

As an effective method to modulate the physicochemical properties of materials, crystal phase engineering, especially hetero‐phase, plays an important role in developing high‐performance photocatalysts. However, it is still a huge challenge but significant to construct porous hetero‐phase nanostructures with adjustable band structures. As a kind of unique porous crystalline materials, metal–organic frameworks (MOFs) might be the appropriate candidate, but the MOF‐based hetero‐phase is rarely reported. Herein, we developed a secondary building unit (SBU) regulating strategy to prepare two crystal phases of Ti‐MOFs constructed by titanium and 1,4‐dicarboxybenzene, i.e., COK and MIL‐125. Besides, COK/MIL‐125 hetero‐phase was further constructed. In the photocatalytic hydrogen evolution reaction, COK/MIL‐125 possessed the highest H2 yield compared to COK and MIL‐125, ascribing to the Z‐Scheme homojunction at hetero‐phase interface. Furthermore, by decorating with amino groups (i.e., NH2‐COK/NH2‐MIL‐125), the light absorbing capacity was broadened to visible‐light region, and the visible‐light‐driven H2 yield was greatly improved. Briefly, the MOF‐based hetero‐phase possesses periodic channel structures and molecularly adjustable band structures, which is scarce in traditional organic or inorganic materials. As a proof of concept, our work not only highlights the development of MOF‐based hetero‐phase nanostructures, but also paves a novel avenue for designing high‐performance photocatalysts.
The Tandem Nitrate and CO2 Reduction for Urea Electrosynthesis: Role of Surface N‐Intermediates in CO2 Capture and Activation
Authors: Huang Xingmiao , Li Yangfan , Xie Shijie , Zhao Qi , Zhang Boyang , Zhang Zhiyong , Sheng Hua , Zhao Jincai
Published: April 2024

Electrochemical reduction of CO2 and nitrate offers a promising avenue to produce valuable chemicals through the using of greenhouse gas and nitrogen‐containing wastewater. However, the generally proposed reaction pathway of concurrent CO2 and nitrate reduction for urea synthesis requires the catalysts to be both efficient in both CO2 and nitrate reduction, thus narrowing the selection range of suitable catalysts. Herein, we demonstrate a distinct mechanism in urea synthesis, a tandem NO3− and CO2 reduction, in which the surface amino species generated by nitrate reduction play the role to capture free CO2 and subsequent initiate its activation. When using the TiO2 electrocatalyst derived from MIL‐125‐NH2, it intrinsically exhibits low activity in aqueous CO2 reduction, however, in the presence of both nitrate and CO2, this catalyst achieves an excellent urea yield rate of 43.37 mmol ⋅ g−1 ⋅ h−1 and a Faradaic efficiency of 48.88 % at −0.9 V vs. RHE in a flow cell. Even at a low CO2 level of 15 %, the Faradaic efficiency of urea synthesis remains robust at 42.33 %. The tandem reduction procedure was further confirmed by in situ spectroscopies and theoretical calculations. This research provides new insights into the selection and design of electrocatalysts for urea synthesis.
Adaptive and Robust Vitrimers Fabricated by Synergy of Traditional and Supramolecular Polymers
Authors: Wang Jiao , You Wei , Chen Liya , Xiao Ding , Xiao Xuedong , Shan Tianyu , Liu Yang , Liu Ming , Li Guangfeng , Yu Wei , Huang Feihe
Published: April 2024

Vitrimers offer a unique combination of mechanical performance, reprocessability, and recyclability that makes them highly promising for a wide range of applications. However, achieving dynamic behavior in vitrimeric materials at their intended usage temperatures, thus combining reprocessability with adaptivity through associative dynamic covalent bonds, represents an attractive but formidable objective. Herein, we couple boron‐nitrogen (B−N) dative bonds and B−O covalent bonds to generate a new class of vitrimers, boron‐nitrogen vitrimers (BNVs), to endow them with dynamic features at usage temperatures. Compared with boron‐ester vitrimers (BEVs) without B−N dative bonds, the BNVs with B−N dative bonds showcase enhanced mechanical performance. The excellent mechanical properties come from the synergistic effect of the dative B−N supramolecular polymer and covalent boron‐ester networks. Moreover, benefiting from the associative exchange of B−O dynamic covalent bonds above their topological freezing temperature (Tv), the resultant BNVs also possess the processability. This study leveraged the structural characteristics of a boron‐based vitrimer to achieve material reinforcement and toughness enhancement, simultaneously providing novel design concepts for the construction of new vitrimeric materials.
Bending performance changes during prolonged canine eruption in saber‐toothed carnivores: A case study of Smilodon fatalis
Authors: Tseng Z. Jack
Published: April 2024

The canine of saber‐toothed predators represents one of the most specialized dental structures known. Hypotheses about the function of hypertrophied canines range from display and conspecific interaction, soft food processing, to active prey acquisition. Recent research on the ontogenetic timing of skull traits indicates the adult canine can take years to fully erupt, but the consequences of prolonged eruption on inferences of canine functional morphology are missing from current discourse and have not been quantified. Here I evaluate hypotheses about adult canine bending strength and stiffness, respectively, during eruption in the felid Smilodon fatalis. Simulated eruption sequences of three adult canines were generated from specimen models to assess shifting cross‐sectional geometry properties, and bending strength and stiffness under laterally directed loads were estimated using finite element analysis. Consistent with beam theory expectations, S. fatalis canine cross‐sectional geometry is optimized for increased bending strength with increased erupted height. However, canine cross‐sectional geometry changes through eruption exaggerate rather than minimize lateral deflection. Spatial constraint for maximum root length from adjacent sensory structures in the maxilla and the recently identified universal power law are hypothesized to limit the growth capacity of canine anteroposterior length and, consequently, maintenance of bending stiffness through eruption. Instead, the joint presence of the deciduous and adult canines for >50% of the adult canine eruption period effectively increases canine mediolateral width and brings bending strength and stiffness estimates closer to theoretical optima. Similarly prolonged retention of deciduous canines in other sabertooths suggests dual‐canine buttressing is a convergently evolved strategy to maximize bending strength and stiffness.
Modified Citrus Pectin (MCP) Confers a Renoprotective Effect on Early‐Stage Nephropathy in Type‐2 Diabetic Mice
Authors: Mahmoud Hager M. , Abdel‐Razik Abdel‐Razik H. , Elrehany Mahmoud A. , Othman Eman M. , Bekhit Amany A.
Published: April 2024

Diabetic nephropathy (DN) is a significant global health concern with a high morbidity rate. Accumulating evidence reveals that Galectin‐3 (Gal‐3), a β‐galactoside‐binding lectin, is a biomarker in kidney diseases. Our study aimed to assess the advantageous impacts of modified citrus pectin (MCP) as an alternative therapeutic strategy for the initial and ongoing progression of DN in mice with type 2 diabetes mellitus (T2DM). The animal model has been split into four groups: control group, T2DM group (mice received intraperitoneal injections of nicotinamide (NA) and streptozotocin (STZ), T2DM+MCP group (mice received 100 mg/kg/day MCP following T2DM induction), and MCP group (mice received 100 mg/kg/day). After 4 weeks, kidney weight, blood glucose level, serum kidney function tests, histopathological structure alterations, oxidative stress, inflammation, apoptosis, and fibrosis parameters were determined in renal tissues. Our findings demonstrated that MCP treatment reduced blood glucose levels, renal histological damage, and restored kidney weight and kidney function tests. Additionally, MCP reduced malondialdehyde level and restored glutathione level, and catalase activity. MCP demonstrated a notable reduction in inflammatory and apoptosis mediators TNF‐α, iNOS, TGF‐βRII and caspase‐3. Overall, MCP could alleviate renal injury in an experimental model of DN by suppressing renal oxidative stress, inflammation, fibrosis, and apoptosis mediators.
Plant‐Derived Coumarins: A Narrative Review of Their Structural and Biomedical Diversity
Authors: Younes Areej Hazem , Mustafa Yasser Fakri
Published: April 2024

Plant‐derived coumarin (PDC) is a naturally occurring heterocyclic backbone that belongs to the benzopyrone family. PDC and its based products are characterized by low toxicity and high distribution in a variety of herbal treatments that have numerous therapeutic potentials. These include anticoagulants, antibacterials, anti‐inflammatory agents, anticancer agents, antioxidants, and others. So, it may be appropriate to investigate the qualities and potential bioactivities of PDCs. This article provides an overview of the biomedical potentials, availability, and clinical use possibilities of PDCs, with a focus on their important modes of action, using information on various pharmacological qualities discovered. The data used in this study came from published research between 2015 and 2023. We reviewed a selection of databases, including PubMed, Scopus, Web of Science, and Google Scholar, during that period. In conclusion, because of their abundance in medicinal plants, the clinical biochemistry attributes of PDCs are currently of interest. In a variety of medical specialties, PDCs serve a useful role as therapeutic agents.
Advances and Strategies towards Synthesis of Aspidosperma Indole Alkaloids Goniomitine
Authors: Ji Cong‐Bin
Published: April 2024

Goniomitine is of the aspidosperma alkaloid family, with an angularly fused tetracyclic skeleton housing an all‐carbon quaternary carbon chiral center alongside an aminal functional group. This natural product has garnered attention as a synthetic target due to its intriguing molecular architecture and anti‐proliferative activity in recent years. Following the first synthesis of (−)‐goniomitine by Takano in 1991, synthetic chemists have developed various methods. This review provides an overview of the methodologies used in the synthesis of goniomitine in racemic and enantiopure forms via divergent construction indole framework, indole functionalization, and the integrated oxidation/reduction/cyclization (iORC) sequence from 1991 to 2023.
Expression of semaphorin‐3A in the joint and role in osteoarthritis
Authors: Li Xiang , Martinez‐Ramos Sara , Heedge Freija T. , Pitsillides Andrew , Bou‐Gharios George , Poulet Blandine , Chenu Chantal
Published: April 2024

Osteoarthritis (OA) is characterised by the deterioration of cartilage in the joints and pain. We hypothesise that semaphorin‐3A (sema‐3A), a chemorepellent for sensory nerves, plays a role in joint degradation and pain. We used the mechanical joint loading (MJL) model of OA to investigate sema‐3A expression in the joint and examine its association with the development of OA and pain. We also analyse its effect on chondrocyte differentiation using the ATDC5 cell line. We demonstrate that sema‐3A is present in most tissues in the healthy joint and its expression increases in highly innervated tissues, such as cruciate ligaments, synovial lining and subchondral bone, in loaded compared to nonloaded control joints. In contrast, sema‐3A expression in cartilage was decreased in the severe OA induced by the application of high loads. There was a significant increase in circulating sema‐3A, 6 weeks after MJL compared to the nonloaded mice. mRNA for sema‐3A and its receptor Plexin A1 were upregulated in the dorsal root ganglia of mice submitted to MJL. These increases were supressed by zoledronate, an inhibitor of bone pain. Sema‐3A was expressed at all stages of Chondrocyte maturation and, when added exogenously, stimulated expression of markers of chondrocyte differentiation. This indicates that sema‐3A could affect joint tissues distinctively during the development of OA. In highly innervated joint tissues, sema‐3A could control innervation and/or induce pain‐associated neuronal changes. In cartilage, sema‐3A could favour its degeneration by modifying chondrocyte differentiation.
Gallbladder volvulus in a 5–years old Vietnamese female: A case report
Authors: Tiep Cao Minh , Ninh Tran Phan , Hung Nguyen Dinh , Nga Nguyen Thi Tuyet , Toan Nguyen Manh , Hung Pham Ngoc , Chuc Dang Van
Published: April 2024

Key Clinical Message

Gallbladder volvulus (GV) is a medical emergency and a rare cause of acute abdominal pain among the pediatric population. GV is more prominent usually in boys in pediatric patients. If it is not diagnosed and surgically intervened promptly, GV will become a life‐threating condition. Fortunately, a safe and effective laparoscopic cholecystectomy is now widely indicated. A 5 years old female patient with abdominal pain and heavy much vomiting was referred to the emergency room in our hospital. She was suspiciously diagnosed with acute inflammation of the gallbladder according to the results of abdominal ultrasound and computerized tomography (CT) scan already performed on admission. One day after the hospitalization, abdominal ultrasound, and CT scan were performed again because of intensification of her abdominal pain and revealed the clinical portrait of GV such as a “floating gallbladder” sign, an echogenic cone structure, an elongated axis displaced horizontally instead of vertically and a lack of intramural blood flow. The acute GV diagnosis was made and the patient was operated, using the laparoscopic cholecystectomy on time, the gallbladder was tightly twisted clockwise at approximately 720°. The operation and postoperative treatment went quite well and the patient was discharged from the hospital on postoperative Day 7. GV is very rare in children, easily omitted or misdiagnosed with cholecystitis. Imaging diagnosis such as ultrasound, CT with contrast helps make diagnosis promptly that avoids severe complications such as gallbladder perforation, necrosis, and biliary peritonitis.
Polydopamine Modified Carbon Nitride and PAMAM Assembled Electrochemical Immunosensor for Detection of Indole‐3‐Acetic Acid
Authors: Zhang Jian , Li Aixue , Yu Xin , Mijakovic Ivan , Pandit Santosh
Published: April 2024

Indole‐3‐acetic acid (IAA) assumes a pivotal role as a phytohormone of utmost importance, intricately orchestrating the nuanced processes associated with the growth and developmental trajectories of botanical organisms. In this study, we have designed and fabricated a label‐free electrochemical impedance immunosensor for the precise detection of IAA. The detection strategy predominantly relied upon polydopamine modified carbon nitride (C3N4) nanosheets (PCN) and polyamidoamine (PAMAM) dendrimer. Through the modification with PCN and PAMAM, the electrode has increased the active area and enhanced the immobilization capacity of antibodies for IAA. The immunosensor‘s ability to capture IAA was significantly improved by enhancing the immunoreaction between the antibody and antigen. This enhancement led to an increased response in the electrochemical behavior of the Fe(CN)63−/4− redox probe. The impedance immunosensor developed exhibits remarkable sensitivity, exceptional selectivity, and consistent performance in the detection of IAA. This assay method, with the potential to replace antibodies, could offer an alternative approach for detecting various phytohormones.
Structure‐Based Design and Synthesis of Lipid A Derivatives to Modulate Cytokine Responses
Authors: Verpalen Enrico C. J. M. , Brouwer Arwin J. , Wolfert Margreet A. , Boons Geert‐Jan
Published: April 2024

Agonists of Toll like receptors (TLRs) have attracted interest as adjuvants and immune modulators. A crystal structure of TLR4/MD2 with E. coli LPS indicates that the fatty acid at C‐2 of the lipid A component of LPS induces dimerization of two TLR4‐MD2 complexes, which in turn initiates cell signaling leading to the production of (pro)inflammatory cytokines. To probe the importance of the (R)‐3‐hydroxymyristate at C‐2 of lipid A, a range of bis‐ and mono‐phosphoryl lipid A derivatives with different modifications at C‐2 were prepared by a strategy in which 2‐methylnaphthyl ethers were employed as permanent protecting group that could be readily removed by catalytic hydrogenation. The C‐2 amine was protected as 9‐fluorenylmethyloxycarbamate, which at a later stage could be removed to give a free amine that was modified by different fatty acids. LPS and the synthetic lipid As induced the same cytokines, however, large differences in activity were observed. A compound having a hexanoyl moiety at C‐2 still showed agonistic properties, but further shortening to a butanoyl abolished activity. The modifications had a larger influence on monophosphoryl lipid As. The lipid As having a butanoyl moiety at C‐2 could selectively antagonize TRIF associated cytokines induced by LPS or lipid A.
Hypervalent Iodine(III) Mediated Halogen Bonded Supramolecular Chiral System with Cholesteryl Naphthalimides
Authors: Zhang Jie , Hao Aiyou , Xing Pengyao
Published: April 2024

Halogen bonding acknowledged as a noteworthy weak interaction, has gained growing recognition in the field of supramolecular chemistry. In this study, we selected structurally rigid diaryliodonium ions (I(III)) with two biaxial σ‐holes as halogen‐bond donors, to bind with three chiral acceptor molecules bearing cholesteryl and naphthalimides with distinct geometries. The abundant carbonyl oxygen atoms in side‐arm substituents function as multiple acceptors for halogen bonding. The self‐aggregation of chiral acceptor molecules demonstrates adaptiveness to solvent media, evidenced by the inversion of the Cotton effect and the morphological evolution from spherical to rod‐like nanoarchitectures in different solvent systems. The distinct geometries of the acceptor molecules conferred various binding modes with I(III). The introduction of I(III) as a halogen‐bond donor regulates the aggregation of the donors, achieving amplification of chiroptical signals and inheriting solvent responsiveness from the self‐aggregated assembly. This study successfully utilized rational structural design and multimodal control strategies to achieve regulation of supramolecular chirality.
Umfassend zugriffssicher
Authors: Fast Arno Martin , Waldeck Boris
Published: April 2024

Die Initiative Manufacturing‐X zielt auf eine digital vernetzte Industrie mit einem standardisierten Datenaustausch über Unternehmens‐ und Branchengrenzen hinweg ab. Diese Kommunikation muss zwingend vor unbefugten Zugriffen abgesichert werden. Die Plattfomtechnologie PLCnext Technology mit offener OPC UA Architektur für die Industrieautomatisierung ist nach IEC62443 zertifiziert und bietet Sicherheit beim Datenaustausch.
Green Lignovation ‐ From incineration to innovation
Authors: Boßmann Manuel , Goericke Hanne , Grotjohann Aishe , Driller Markus
Published: April 2024

Beim 6. ChemPlant‐Wettbewerb sind theoretisches Wissen und praktisches Können der Verfahrenstechnik gefragt. Im Jahr 2023 beteiligten sich 13 Studierendenteams aus 12 Hochschulen an dem Wettbewerb der kreativen jungen Verfahrensingenieure (kjVI) in der VDI‐Gesellschaft Verfahrenstechnik und Chemieingenieurwesen (VDI‐GVC). Den 6. Wettbewerb gewann das Team der RWTH Aachen. Die jungen Ingenieure überzeugten mit der nachhaltigen Herstellung von fraktioniertem Lignin und wichtigen Plattformchemikalien aus Schwarzlauge.
Medical education and artificial intelligence: Question answering for medical questions based on intelligent interaction
Authors: Chen Lei
Published: April 2024

Computer assisted medical diagnosis technology is widely used in the field of medical assistance to assist doctors in making diagnostic decisions. But as the number of patients increases, the diagnostic pressure on doctors gradually increases, and more efficient computer‐aided medical diagnosis technology is needed to improve the accuracy of doctors' diagnosis. Today's computer‐based medically assisted diagnostic technologies suffer from the inability to fully simulate physical attributes and environmental factors, the large computational resources required for high‐precision models, the need for professional training for user operation, and the limited intuition for innovative design. For improving diagnostic efficiency, this study designs a medical Question answering intelligent interaction system in view of artificial intelligence algorithms. The system is constructed with an active interactive intelligent Q&A model consisting of a medical reasoning module and a medical examination recommendation module. Then, it uses local Bayesian network algorithm as the foundation to establish an intelligent strategy optimization network. And it puts forward the answer selection model of medical Question answering in view of hierarchical interaction for natural language processing tasks in the medical context. The performance test results show that when the diagnostic end threshold of the medical reasoning module is 0.8, the shortest diagnostic path is 3.33. When the diagnostic threshold is 0.85, the maximum length of the diagnostic path is 4.66, and the maximum difference between the diagnostic paths is 1.33, which is basically not affected by the diagnostic end threshold. The local Bayesian network algorithm can reduce the impact of noise features and extract more valuable information. The accuracy of the multilevel interactive answer selection model on the Stanford Natural Language Inference dataset without using external resources reached 89.2%. The ablation test results show that the overall accuracy of the model is 89.64%. The visualization results of the attention weight distribution test between interaction layers show that under different levels of interaction, the attention distribution will undergo significant changes.
A lightweight performance proxy for deep‐learning model training on Amazon SageMaker
Authors: Keller Tesser Rafael , Marques Alvaro , Borin Edson
Published: April 2024

Cloud computing has become popular for training deep‐learning (DL) models, avoiding the costs of acquiring and maintaining on‐premise systems. SageMaker is a cloud service that automates the execution of DL workloads. Its features include automatic hyperparameter optimization and use of spot instances. Nonetheless, it does not assist in selecting the right instance type for a workload. In public clouds, rent price depends on the configuration of the chosen instance type. Advanced and faster instances are typically more expensive, but not always the best choice. To select the optimal instance type, users must compare the workload's relative performance (and hence cost) on several candidates. Building on the execution profiles of multiple DL applications, we model the performance and cost of training DL applications on SageMaker and propose a lightweight technique to estimate these at low temporal and monetary cost. This method is a performance proxy that can be used to replace more expensive performance measurement procedures. So, it could speed up any technique that relies on such measurements. We show how it can help cloud customers seeking suitable instance types to train DL models, and that it can accurately predict the performance of different instance types when training these models on SageMaker.
Astrocytic functions and lipid metabolism: Correlations and therapeutic targets in Alzheimer's disease and glioblastoma
Authors: Zhang Xu , Gao Rongrong , Yang Liuke , Zhu Youwei , Zhang Tiancheng , Shen Xiaorong , Gu Wenwen , Yang Long , Peng Shenjie
Published: April 2024

Background

The brain is a central key organ of the body containing the second highest lipid content only after adipose tissue. Lipids as the main structural components of biological membranes play important roles in a vast number of biological processes within the brain such as energy homeostasis, material transport, signal transduction, neurogenesis and synaptogenesis, providing a balanced cellular environment required for proper functioning of brain cells. Lipids and their metabolism are of great physiological importance in view of the crucial roles of lipids in brain development and function. Astrocytes are the most abundant glial cells in the brain and involved in various processes including metabolic homeostasis, blood brain barrier maintenance, neuronal support and crosstalk.

Results

Disturbances in lipid metabolism and astrocytic functions may lead to pathological alterations associated with numerous neurological diseases like Alzheimer's disease (AD) recognised as the most frequent cause of dementia leading to major progressive memory and cognitive deficits as well as glioblastoma (GBM) known as the most aggressive malignant brain tumour with a poor prognosis.

Conclusions

Herein, we not only review the level and role of altered lipid metabolism in correlation with astrocytic function and astrocyte‐neuron crosstalk in AD and GBM, but also discuss important lipid‐related metabolites and proteins participating in possible mechanisms of pathologically dysregulated lipid metabolism, offering potential therapeutic targets in targeted molecular therapies for AD and GBM.
Instability analysis and face‐to‐face collision of dust acoustic waves in dusty plasmas: Perspective Jupiter environment
Authors: Imon Umma , Alam M. S.
Published: April 2024

The collisionless unmagnetized five components dusty plasmas have been considered to study the significance of the face‐to‐face collision of single‐ and multi‐solitons, phase shifts due to face‐to‐face collision, and instability of the dust acoustic waves in Jupiter's environment. To study the consequence of face‐to‐face collision extended Poincaré–Lighthill–Kuo method is used to derive the two‐sided nonlinear Korteweg–De Vries (KdV) equation. Besides, to investigate the dust acoustic wave's instability, the nonlinear Schrödinger equation has been derived following the procedure of Slathia et al. The multi‐soliton solutions are determined by employing the Hirota bilinear method. The concerned parameters in the issue play a crucial role in the phase shift (generated by the face‐to‐face collision); the collisional process of single‐, double‐, triple‐, and quadruple‐soliton; and the generation of dust acoustic solitons. Furthermore, the plasma parameters are crucial in the formation of dark solitons and envelop shocks.
The neoteny goldilocks zone: The evolution of neoteny in Ambystoma
Authors: Lyons Thom A. , Arbuckle Kevin
Published: April 2024

Neoteny is a developmental strategy wherein an organism reaches sexual maturity without associated adult characteristics. In salamanders, neoteny takes the form of individuals retaining aquatic larval characteristics such as external gills upon maturation. Mole salamanders (Ambystoma) occupy a wide range of habitats and areas across the North American continent, and display examples of non‐neotenic, facultatively neotenic and obligate neotenic species, providing high variation for investigating the factors influencing the evolution of neoteny. Here, we use phylogenetic comparative methods to test existing hypotheses that neoteny is associated with elevational and latitudinal distribution, cave‐associated isolation, and hybridisation‐related polyploidy. We also test if neoteny influences the diversity of habitats a species can occupy, since the restriction to an aquatic life should constrain the availability of different niches. We find that neoteny tends to occur in a narrow latitudinal band between 20–30° North, with particularly narrow latitudinal ranges for obligate compared to facultative neotenic species (16–52° North). We also find that facultatively neotenic species occur at elevations more than twice as high as other species on average, and that species with a higher frequency of neoteny typically have lower habitat diversity. Our results suggest that evolutionary transitions between non‐neotenic and facultative neoteny states occur at relatively high and approximately equal rates. Moreover, we estimate that obligate neoteny cannot evolve directly from non‐neotenic species (and vice versa), such that facultative neoteny acts as an evolutionary ‘stepping stone’ to and from obligate neoteny. However, our transition rate estimates suggest that obligate neoteny is lost >4‐times faster than it evolves, partly explaining the rarity of obligate species. These results support the hypothesis that low latitudes favour the evolution of neoteny, presumably linked to more stable (aquatic) environments due to reduced seasonality, but once evolved it may constrain the diversity of habitats.
Closing the Gap Between Gas Phase and Condensed Phase: Fragmentation Studies of the Thiomethoxymethyl Complex [(bipy)Pt(CH3)2(CH2SCH3)]+
Authors: Stebens Gilles , Jakob Lukas , Butschke Burkhard
Published: April 2024

Collision‐induced dissociation (CID) of the mass‐selected cation [(bipy)Pt(CH3)2(CH2SCH3)]+ in an ion‐trap mass‐spectrometer results in the losses of the neutrals ethane, ethene, dimethyl sulfide, methane, ethyl methyl sulfide, and propane. The generation of the first four neutrals is also observed, when the isolated, dimeric complex [(bipy)Pt(CH3)2(CH2SCH3)]2[SbF6]2 is heated in the condensed phase. While the product distribution is very similar regardless of whether the complex is heated in the solid state or in solution, ethane loss, i. e. the quite rare event of an sp3‐sp3 C−C reductive elimination from a platinum(IV) complex, dominates in the gas‐phase experiment. However, when the counter anion [SbF6]− is exchanged by the more weakly coordinating anion [BAr4F]−, the amounts of ethane and ethene are increased also in the condensed phase. These sum of observations indicates the similarities of the fragmentation of [(bipy)Pt(CH3)2(CH2SCH3)]+ in both phases. Thus, a correlation of processes in both environments is possible for selected systems (and particularly for unimolecular processes), but the choice of the proper conditions is crucial for a meaningful comparison.
Steady‐state operating points of islanded virtual synchronous machine microgrid
Authors: Kamilu Sanusi Alabi , Beck Hans‐Peter
Published: April 2024

Before starting stability analysis of the multivirtual synchronous machine (n‐VISMA) power system, it is necessary to obtain the steady‐state operating points (SSOPs) of all dynamic nodes in the network. Modified traditional iterative schemes using the concept of droop bus technique in an islanded microgrid are not feasible for load flow analysis of VISMA microgrid incorporating non‐control dynamics. This paper proposes closed‐form steady‐state, fundamental‐frequency models for islanded VISMA microgrids using the concept of virtual swing buses. In this technique, the virtual internal buses of all VISMAs in the network are governed by the swing equation. The voltage at all buses is variable except the virtual buses in which the pole wheel voltages are prespecified. The algorithm was extended by a droop control localized to each VISMA. The suitability of the proposed algorithm to obtaining SSOPs of VISMA was tested on IEEE‐9 bus system with VISMA replacing electromechanical synchronous machines and also on a low‐voltage distribution system. To validate the applicability of the proposed algorithm and prove its accuracy, the case study systems were also modeled in the SIMULINK environment for detailed time domain analysis. The algorithm was found to be computationally effective for a load flow analysis of the VISMA microgrid. The results also reveal that the addition of external droop control improves the frequency stability of the system.
Fulfilling the promise of digital tools to build rangeland resilience
Authors: Bestelmeyer Brandon T , McCord Sarah E , Browning Dawn M , Burkett Laura M , Elias Emile , Estell Rick E , Herrick Jeffrey E , James Darren , Spiegal Sheri , Utsumi Santiago A , Webb Nicholas P , Williamson Jeb
Published: April 2024

The world's rangelands and drylands are undergoing rapid change, and consequently are becoming more difficult to manage. Big data and digital technologies (digital tools) provide land managers with a means to understand and adaptively manage change. An assortment of tools—including standardized field ecosystem monitoring databases; web‐accessible maps of vegetation change, production forecasts, and climate risk; sensor networks and virtual fencing; mobile applications to collect and access a variety of data; and new models, interpretive tools, and tool libraries—together provide unprecedented opportunities to detect and direct rangeland change. Accessibility to and manager trust in and knowledge of these tools, however, have failed to keep pace with technological advances. Collaborative adaptive management that involves multiple stakeholders and scientists who learn from management actions is ideally suited to capitalize on an integrated suite of digital tools. Embedding science professionals and experienced technology users in social networks can enhance peer‐to‐peer learning about digital tools and fulfill their considerable promise.
Appetite sensation improvement by synbiotic supplementation in patients with metabolic syndrome: A randomized controlled clinical trial
Authors: Hosseini Fatemeh , Pourjam Mahboube , Mirzaeian Soheila , Karimifar Mozhgan , Feizi Awat , Entezari Mohammad Hassan , Saraf‐Bank Sahar
Published: April 2024

The potential link between dysbiosis, features of metabolic syndrome (MetS), inflammation, and sensation impairment has been recently recognized. However, in this context, there are few indications available regarding the effects of co‐supplementation with Bacillus indicus, Bacillus coagulans, and fructooligosaccharide (FOS) prebiotics on patients with MetS. Therefore, this study aimed to investigate the effects of synbiotic supplementation on glycemic indices, inflammatory biomarkers, and appetite among adults with MetS. This study is a randomized, double‐blind, placebo‐controlled clinical trial conducted in the Endocrine and Metabolism Research Center outpatient clinic in Isfahan, Iran. Fifty‐eight MetS patients were randomly assigned to receive either synbiotics (n = 29) or placebo (n = 29) supplementation twice per day for 8 weeks. Finally, 55 patients were recruited for analyses (28 in the intervention group and 27 in the placebo group). Random permuted blocks and a computer‐generated random number table were used for treatment allocation. No adverse effects were reported during the study. There were no significant differences in glycemic indices and inflammatory markers within‐ and between groups (all p > .05). However, a significant increase in the sensation of fullness was documented in the synbiotic group. In conclusion, the eight‐week treatment did not improve glycemic control and inflammatory markers. Nevertheless, it demonstrated potential efficacy in enhancing participants' appetite sensations, warranting further evaluation in longer intervention periods during future clinical trials.
Association between hepcidin levels and inflammatory bowel disease: A systematic review and meta‐analysis of observational studies
Authors: Soltanieh Samira , Salavatizadeh Marieh , Gaman Mihnea‐Alexandru , Kord Varkaneh Hamed , Tan Shing Cheng , Prabahar Kousalya , Lozovanu Oana Deliu , Santos Heitor O. , Hekmatdoost Azita
Published: April 2024

Hepcidin has a crucial role in iron homeostasis upon inflammatory conditions such as inflammatory bowel disease (IBD). Thus, we conducted a systematic review and meta‐analysis to determine the overall association between serum hepcidin concentrations and IBD. Based on the preferred reporting items for systematic review and meta‐analysis (PRISMA) protocols, an electronic literature search was conducted on PubMed/MEDLINE, Scopus, and Web of Science until June 2020. Studies were deemed eligible for inclusion if they met the following criteria: (1) diagnosis of IBD, (2) observational design, and (3) measured serum hepcidin and prohepcidin concentrations in IBD patients and control group. Overall, 10 studies including 1184 participants were evaluated. Random‐effects meta‐analysis revealed that subjects with IBD had 7.22 ng/mL (95% CI: 2.10, 12.34; p = .006) higher serum hepcidin concentrations compared to control groups. A nonsignificantly lower serum prohepcidin concentration (0.522 ng/mL, 95% CI: −1.983 to 0.939; p = .484) was found for IBD patients compared to healthy subjects. However, there was significant heterogeneity among the studies regarding both hepcidin (I2 = 98%, p < .001) and prohepcidin levels (I2 = 96%, p < .001), respectively. In an age‐based subgroup analysis, patients aged ≥18 years with IBD displayed higher serum hepcidin levels when compared to healthy individuals (22.36 ng/mL, 95% CI, 2.12–42.61; p = .030). Hepcidin concentrations are elevated in subjects with IBD; however, the clinical relevance of this finding requires further evaluation in future investigations as the increase is relatively small compared to the wide range of normal hepcidin values.
Consumer Centric Flexible Demand Management
Authors: McLean‐Conner Penni
Published: April 2024

Traditional demand response is a proven and effective tool to address peak energy demand. In this model, consumers respond to a call for action by the electric grid operator. It is an effective—but blunt—instrument and one that will continue to play an important role in responding to times when the grid is stressed.
The Current State of the National Electric Vehicle Infrastructure Program Funding
Authors: Woodle Nolan , Olivier Jordan , Cappa Claudia
Published: April 2024

Reducing the transportation sector's greenhouse gas (GHG) emissions by transitioning away from fossil fuels and its impact on communities and the environment continues to receive considerable attention. In 2022, the U.S. transportation sector was responsible for generating the largest share of the United States' GHG emissions at approximately 37 percent of total emissions.1 Electric vehicles (EVs) represent a viable option that can contribute significantly to reducing transportation sector emissions. As EVs become increasingly prevalent, ensuring the availability of adequate charging infrastructure to support these vehicles is a top priority of the Biden Administration and many states.
Water reservoirs influenced by slow moving landslides
Authors: Marte Roman
Published: April 2024

Water storages for energy production in mountain valleys or snow retention basins on mountain slopes or mountain ridges are common buildings in Alpine regions. When such water reservoirs are situated on or nearby of a large slow‐moving landslide, low factors of safety and ongoing deformation of the reservoir structure – or parts of it – need to be handled in some cases. Questions about the justification but also the reliability of reservoirs influenced by such landslides need to be discussed. Verification procedures which proof a save operation of the reservoir over time but also an estimation of the behaviour of the reservoir influenced by the landslide for exceptional load cases need to be investigated. In this paper main issues and problems related to such questions are discussed for reservoirs in the design as well as in the operation state which are influenced by such slow moving landslides.
Downregulated expression of lactate dehydrogenase in adult oligodendrocytes and its implication for the transfer of glycolysis products to axons
Authors: Späte Erik , Zhou Baoyu , Sun Ting , Kusch Kathrin , Asadollahi Ebrahim , Siems Sophie B. , Depp Constanze , Werner Hauke B. , Saher Gesine , Hirrlinger Johannes , Möbius Wiebke , Nave Klaus‐Armin , Goebbels Sandra
Published: April 2024

Oligodendrocytes and astrocytes are metabolically coupled to neuronal compartments. Pyruvate and lactate can shuttle between glial cells and axons via monocarboxylate transporters. However, lactate can only be synthesized or used in metabolic reactions with the help of lactate dehydrogenase (LDH), a tetramer of LDHA and LDHB subunits in varying compositions. Here we show that mice with a cell type‐specific disruption of both Ldha and Ldhb genes in oligodendrocytes lack a pathological phenotype that would be indicative of oligodendroglial dysfunctions or lack of axonal metabolic support. Indeed, when combining immunohistochemical, electron microscopical, and in situ hybridization analyses in adult mice, we found that the vast majority of mature oligodendrocytes lack detectable expression of LDH. Even in neurodegenerative disease models and in mice under metabolic stress LDH was not increased. In contrast, at early development and in the remyelinating brain, LDHA was readily detectable in immature oligodendrocytes. Interestingly, by immunoelectron microscopy LDHA was particularly enriched at gap junctions formed between adjacent astrocytes and at junctions between astrocytes and oligodendrocytes. Our data suggest that oligodendrocytes metabolize lactate during development and remyelination. In contrast, for metabolic support of axons mature oligodendrocytes may export their own glycolysis products as pyruvate rather than lactate. Lacking LDH, these oligodendrocytes can also “funnel” lactate through their “myelinic” channels between gap junction‐coupled astrocytes and axons without metabolizing it. We suggest a working model, in which the unequal cellular distribution of LDH in white matter tracts facilitates a rapid and efficient transport of glycolysis products among glial and axonal compartments.
Electrocardiography changes and different stages of heart failure in central Iran: A cross‐sectional study from Yazd Health Study
Authors: Sadeghi Sedighe , Jokar Mojtaba , Tezerjani Seyed Mostafa Seyed Hossieni , Haghaninejad Hasan , Zare Elahe , Meybodi Mahmood Emami , hassanabadi Mohammadtaghi Sareban , Mirzaei Masoud , Mohammadi Hamidreza , Tabatabaei Forough Sadat
Published: April 2024

Background and Aims

Electrocardiography (ECG) is a widely accessible, noninvasive, and cost‐effective diagnostic instrument used to evaluate patients with suspected heart failure (HF). The aim of this study is to investigate electrocardiographic changes in patients with different stages of HF in a random population of Yazd city.

Methods

This prospective cross‐sectional study included 319 individuals, randomly selected, aged 40 years and more, registered in the Yazd Health Study was conducted from March 2022 to May 2023 at Afshar Hospitals. In accordance with the AHA/ACC guidelines, HF was classified into four stages (A, B, C, and D).

Results

The 159 individuals were classified in the stage 0 group, 77 were in Stage A, 65 were in Stage B, and 18 were in Stage C of HF. In the Stage 0, the PR interval (PRi) was 130.5 ± 18.1 ms, while in Stage C, it was 143.3 ± 21.9 ms, with a significant difference (p = 0.047). Similarly, the QRS interval (QRSi) increased with HF staging (p = 0.001). The frequency of diabetes mellitus (DM), hypertension (HTN), hyperlipidemia (HLP), chronic heart disease, alcoholism, and PRi, QRSi, QT interval levels were independent predictors of HF stage in multivariate regression analysis.

Conclusion

The prevalence of HF stages, as classified by the AHA/ACC guidelines, was observed, with significant correlations between ECG parameters and HF progression. abnormal rhythms, left bundle branch block, ischemia, hypertrophy, and left atrial enlargement increased with higher HF stages. Major risk factors like DM and HTN exhibited a heightened prevalence in advanced HF stages, accentuating their pivotal role in the progression of HF.