bluuebunny/crossref_metadata_2025 huggingface dataset:
Can Metal Cations Electrocatalyze Sulfur Redox Reaction and Suppress Polysulfide Shuttle?
Authors: Kumar Subramani , Swain Gitanjali , Krishnamoorthy Kothandam
Published: July 2023

In lithium‐sulfur (Li−S) batteries, sulfur undergoes various changes. It switches between cyclic structure and linear structure. The charge on the sulfur varies between a neutral state and a negative charge‐bearing state. Due to these changes, the sulfur/polysulfide dissolves in the battery electrolyte. Furthermore, the kinetics of the sulfur redox reaction is sluggish. Therefore, a material that can suppress sulfur/polysulfide dissolution and electrocatalyze sulfur redox reaction is needed. We hypothesize that the polysulfide dissolution can be suppressed if the host exhibits polyvalent electrostatic attraction. Polysulfide is a negative charge‐bearing molecule; hence the host must comprise multiple positive charges. Nickel cations with other heteroatoms have been explored as a host in Li−S batteries. The heteroatoms impart additional interactions. The easier way to circumvent the effect of heteroatoms is the addition of metal salts. However, metal salts can either exhibit monovalent or divalent attraction with polysulfides. Those interactions are weak and we must have polyvalent interaction. Towards this objective, we have designed and synthesized a material that comprises multiple divalent cations that is also devoid of heteroatoms. The Li−S batteries fabricated using the metal cation immobilized graphene showed a maximum specific capacity of 1022 mAh/g at 0.1 C rate. Among the metal cations, nickel cations showed better performance than cobalt cations. Thus, we demonstrate that metal cations immobilized on Graphene can efficiently electrocatalyze the sluggish sulfur redox reaction and suppress the polysulfide dissolution.
LiBF4 Induced Unique Surface Modification Enables Improved Electrochemical Performance of LiNi0.8Co0.1Mn0.1O2 Cathode
Authors: Zhou Xiaolin , Li Sihan , Feng Ze , Zhang Shan , Fan Xin , Wang Yan , Sun Dan , Li Huanhuan , Tang Yougen , Wang Haiyan , Li Jianfeng , Wei Jingchao
Published: July 2023

LiNi0.8Co0.1Mn0.1O2 (NCM811) has been regarded as a potential cathode material for next‐generation lithium‐ion batteries. However, the electrochemical performance of this material is severely affected by structural deterioration and capacity degradation, and the residual lithium is one of the main culprits. Herein, we propose an effective strategy to design ultrathin coatings on the surface of NCM811 by using LiBF4 as the precursor. The homogeneous hybrid LiF‐Li2B4O7 coating layers can be obtained due to the reaction between LiBF4 and the residual lithium, which can not only effectively reduce the residual lithium, but also improve interfacial lithium‐ion diffusion kinetics and suppress side reactions. Accordingly, the LiBF4‐modified samples exhibited significantly improved electrochemical performance. The coated sample of NCM811@LBF‐0.7 delivers the 127.1 mAh g−1 discharge capacity with 69.8 % capacity retention even after 300 cycles at 1 C. While the pristine sample only shows 97.1 mAh g−1 and the capacity retention decreases to 31.0 %. This method provides a simple and effective strategy to extend the service life and safety characteristics of high‐energy‐density lithium‐ion batteries.
Characterization of tyrosine ammonia lyases from Flavobacterium johnsoniae and Herpetosiphon aurantiacus
Authors: Virklund Alexander , Jendresen Christian Bille , Nielsen Alex Toftgaard , Woodley John M.
Published: July 2023

p‐Coumaric acid (pCA) can be produced via bioprocessing and is a promising chemical precursor to making organic thin film transistors. However, the required tyrosine ammonia lyase (TAL) enzyme generally has a low specific activity and suffers from competitive product inhibition. Here we characterized the purified TAL variants from Flavobacterium johnsoniae and Herpetosiphon aurantiacus in terms of their susceptibility to product inhibition and their activity and stability across pH and temperature via initial rate experiments. FjTAL was found to be more active than previously described and to have a relatively weak affinity for pCA, but modeling revealed that product inhibition would still be problematic at industrially relevant product concentrations, due to the low solubility of the substrate tyrosine. The activity of both variants increased with temperature when tested up to 45°C, but HaTAL1 was more stable at elevated temperature. FjTAL is a promising biocatalyst for pCA production, but enzyme or bioprocess engineering are required to stabilize FjTAL and reduce product inhibition.
A new dimension in medical education: Virtual reality in anatomy during COVID‐19 pandemic
Authors: Miltykh Ilia , Kafarov Edgar S. , Covantsev Serghei , Dadashev Ali S. , Skarlis Apostolos A. , Zenin Oleg K.
Published: July 2023

Virtual reality technology has been increasingly used in the field of anatomy education, particularly in response to the COVID‐19 pandemic. Virtual reality in anatomy (VRA) allows the creation of immersive, three‐dimensional environments or experiences that can interact in a seemingly real or physical way. A comprehensive search of electronic databases was conducted to identify relevant studies. The search included studies published between 2020 and June 2023. The use of VRA education has been shown to be effective in improving students' understanding and retention of knowledge, as well as developing practical skills such as surgical techniques. VRA can allow students to visualize and interact with complex structures and systems in a way that is not possible with traditional methods. It can also provide a safe and ethical alternative to cadavers, which may be in short supply or have access restrictions. Additionally, VRA can be used to create customized learning experiences, allowing students to focus on specific areas of anatomy or to repeat certain exercises as needed. However, there are also limitations to the use of VRA education, including cost and the need for specialized equipment and training, as well as concerns about the realism and accuracy of VRA models. To fully utilize the potential of VRA education, it is important for educators to carefully consider the appropriate use of VR and to continuously evaluate its effectiveness. It is important for educators to carefully consider the appropriate use of VRA and to continuously evaluate its effectiveness to fully utilize its potential.
Protect personal, institutional data from cyberattacks
Authors: McCarthy Claudine
Published: July 2023

BOSTON — If your institution falls prey to a cybersecurity attack, it risks not only potential reputational damage and financial loss but also lawsuits claiming breach‐of‐contract or failure to comply with privacy policies/laws.
Transitional leadership is a post‐COVID opportunity for progress
Authors: Skipworth Stan
Published: July 2023

For many of us, we are likely approaching or have just gotten underway with a new academic year. As this new start unfolds, I find myself just a couple of months into an exciting opportunity: a new role for a long‐time leader in the Southern California Region of higher education.
Did court dismiss student's Title IX retaliation claim?
Authors: Lyerly Eric
Published: July 2023

A student at the University of Pennsylvania was granted leaves of absence for medical reasons.
Two New Eudesmane‐Type Sesquiterpene from Clonostachys sp. Y6‐1and Their Cytotoxic Activity
Authors: Wang Mengru , Yang Run , Chen Yuansi , Ni Dongxuan , Bi Dewen , Li Qi , Huang Jiabi , Wang Hairong , Wang Weiguang , Li Hongliang , Xiao Weilie
Published: July 2023

Two undescribed eudesmane‐type sesquiterpenoids together with four known compounds were isolated from Clonostachys sp. Y6‐1 associated. Their chemical structures were unambiguously determined by NMR, mass spectrometry, and 13C‐NMR calculation as well as DP4+ probability analyses. The absolute configurations of compounds 1 and 2 were determined by ECD calculation and X‐ray single‐crystal diffraction methods. Furthermore, all isolates were evaluated for in vitro cytotoxic activities against MCF‐7, HCT‐116, MDA‐MB‐231, and SW620 cancer cells. Among them, bioactivity evaluation of compound 5 revealed that weak activity (IC50=66.55±0.82 μM) against SW620.
Severe arsenic poisoning due to Ayurvedic supplements
Authors: Hardin Jeremy , Seltzer Justin , Suhandynata Raymond , Spiegel Benjamin , Silver Robin , Thomas Diane , Galust Henrik , Friedman Nathan , Clark Richard , Momper Jeremiah
Published: July 2023

Key Clinical Message

Patients that are taking Ayurvedic supplements have an increased risk of heavy metal toxicity. Lead, arsenic, and mercury are frequently identified in these supplements and can cause clinically significant toxicity. Clinicians should screen patients routinely for use of non‐pharmaceutical medications and supplements.
Co‐Catalyzed Hydrosilylation of Ketones under Base‐Free Conditions: A Convenient Route to Silyl Ethers or Secondary Alcohols
Authors: Stachowiak‐Dłużyńska Hanna , Hreczycho Grzegorz
Published: July 2023

A cobalt‐catalyzed addition of hydrosilanes to unsaturated carbon‐oxygen bonds has been developed, relying on complexes featuring easily accessible and inexpensive PNP‐type pincer ligands. A wide range of heterocyclic, aliphatic, and aromatic ketones, including those containing both electron‐donating and electron‐withdrawing substituents, were transformed into silyl ethers or secondary alcohols with high yields. An important feature of this protocol is that silanes can act as both the substrates and activators, eliminating the need for external additives such as strong bases.
Lipase/H2SO4‐Cocatalyzed Dynamic Kinetic Resolution of Alcohols in Pickering Emulsion
Authors: Moon Jihoon , Kin Takusho , Mizuno Karin , Akai Shuji , Kanomata Kyohei
Published: July 2023

This study reports the first chemoenzymatic dynamic kinetic resolution (DKR) of racemic sec‐alcohols by simultaneously using immobilized lipase and aqueous sulfuric acid as catalysts for kinetic resolution and racemization, respectively. The nanoparticle‐stabilized phase separation in a Pickering emulsion enabled the use of these inherently incompatible catalysts in a single vessel. The racemization reaction in the aqueous sulfuric acid solution significantly suppressed the dehydrative side reactions that form alkenes and dimeric ethers, which are often observed in racemization using Brønsted/Lewis acids or oxovanadium compounds in organic solvents. The efficacy of the Pickering emulsion was confirmed by the significantly lower catalytic performance in DKR without emulsification. This method achieved high yields and high optical purities in the production of a wide range of sec‐alcohols.
A Numerical Simulation of Multiple‐Droplet Coalescence Characteristics under an Electric Field
Authors: Meng Min , Feng Silong
Published: July 2023

A phase field method based on the Cahn‐Hilliard equation was used to establish a numerical model for the motion and coalescence of multiple droplets under an electric field. The influencing factors of the droplet coalescence rate, velocity field and pressure field distributions, and droplet cluster motion and coalescence were investigated. The observations showed that the dynamic behaviors of droplets under the action of the electric field can be characterized as not coming together, coalescence, and breakup after coalescence. High‐speed (low‐speed) and high‐pressure (low‐pressure) regions are generated inside the droplet or near the interface under the action of the electric field, and the size, number, and location of these regions change over time. The results of this study offer an essential guide for developing new electrostatic coalescers.
Catalytic Amination of Alcohols Using Diazo Compounds under Manganese Catalysis Through Hydrogenative N‐Alkylation Reaction
Authors: Babu Reshma , Sukanya Padhy Subarna , Kumar Rohit , Balaraman Ekambaram
Published: July 2023

Sustainable chemical production requires fundamentally new types of catalysts and catalytic technologies. The development of coherent and robust catalytic systems based on earth‐abundant transition metals is essential, but highly challenging. Herein, we systematically explored a general hydrogenative cleavage/N‐alkylation tandem of cyclic and acyclic diazo (N=N) compounds to value‐added amines under manganese catalysis. The reaction is catalyzed by a single‐site molecular manganese complex and proceeds via tandem dehydrogenation, transfer hydrogenation, and borrowing hydrogenation strategies. Interestingly, the reaction involves abundantly available renewable feedstocks, such as alcohols, that can act as (transfer)hydrogenating and alkylating agents. The synthetic application of our approach in large‐scale pharmaceutical synthesis and easy access to highly demanding N‐CH3/CD3 derivatives are also demonstrated. Kinetic studies show that the reaction rate depends on the concentration of alcohol and Mn‐catalyst and follows fractional orders. Several selective bond activation/formation reactions occur sequentially via amine–amide metal‐ligand cooperation.
Nachhaltige Kraftstoffe
Authors: Daschner Robert , Apfelbacher Andreas
Published: July 2023

Im Projekt To‐Syn‐Fuel wurde ein vom Fraunhofer Institut Umsicht entwickeltes Verfahren zur Herstellung von Kraftstoffen aus Biomassereststoffen im Demonstrationsmaßstab umgesetzt. Während der Laufzeit wurden aus 500 t Klärschlamm mehr als 50.000 L biogenes Rohöl gewonnen.
Pflege von biobasierten Kühlschmierstoffen
Authors: Fuhrmann Philipp
Published: July 2023

Eine sorgfältige überwachung und Pflege von Kühlschmierstoffen zum Beispiel in Pumpen unerlässlich. Einen wichtigen Teil der Pflege stellt die Abtrennung fester Fremdstoffe dar. Eine exzellente Möglichkeit hierzu bietet die Dynamische Crossflow Filtration (DCF) mit keramischen Filterscheiben.
Alternating Copolymerization of Epoxides and Isothiocyanates to Diverse Functional Polythioimidocarbonates and Related Block Polymers†
Authors: Zhu Xiao‐Feng , Lu Xin‐Yu , Xu Cheng‐Kai , Fang Yu‐Bo , Yang Guan‐Wen , Li Wei , Wang Jingdai , Wu Guang‐Peng
Published: July 2023

Comprehensive Summary

Synthesis of diverse polythioimidocarbonates via ring‐opening copolymerization of epoxides and isothiocyanates catalyzed by organoboron catalyst was reported herein. Both aromatic and aliphatic isothiocyanates underwent successful copolymerization with terminal and internal epoxides, allowing for the precise tuning of the performance of the resultant copolymers over a broad range. The wide scope of available isothiocyanates and epoxides enables the direct construction of sulfur‐containing functional polymers featuring both high glass transition temperature and refractive index. Additionally, it was observed that aromatic isothiocyanates polymerize much faster than aliphatic ones, and the reactivity difference facilitated the one‐step synthesis of block polymers from mixed aromatic isothiocyanates, aliphatic isothiocyanates and epoxides due to the preferential incorporation of aromatic isothiocyanates over the aliphatic analogues during their alternating copolymerization with epoxides. The produced polythioimidocarbonates can be used as positive resists for electron beam lithography (sensitivity of 130 μC/cm2 and contrast of 1.53 for poly(CHO‐alt‐EITC)). Coupling with their high refractive index (1.58—1.68), polythioimidocarbonates might find functional applications in optics. These results render ring‐opening copolymerization of epoxides and isothiocyanates a facile route to enrich functional polymer library.
Trace cadmium determination in lake water matrix by flame atomic absorption spectrometry after manganese ferrite magnetic nanoparticles‐based dispersive solid phase extraction
Authors: Karaman Devrim Nur , Serbest Hakan , Kilinç Yağmur , Demirel Rabia , Bakırdere Sezgin
Published: July 2023

In this study, manganese ferrite magnetic nanoparticles‐based dispersive solid phase extraction (MF‐MNP‐DSPE) was developed for cadmium determination at trace level by flame atomic absorption spectrometry (FAAS). Manganese ferrite‐based magnetic nanoparticles were synthesized to be used as solid phase extraction sorbent. All the analytical conditions were optimized by univariate optimization approach to achieve high enrichment factors. Under the optimum conditions, limit of detection (LOD) and quantification (LOQ) values of the developed method were recorded as 1.3 and 4.3 µg L−1, respectively. Approximately 135‐fold improvement in the detection power by the MF‐MNP‐DSPE‐FAAS system was recorded over the traditional FAAS system based on LOD comparison. Recovery experiments were performed to test the applicability/accuracy of the developed method with lake water spiked at different concentrations. Percent recovery values were obtained between 87% and 112% by employing the matrix matching calibration strategy and this showed that the developed method is applicable for the determination of cadmium in lake water samples with high accuracy and precision.
Back in Person: Frontiers in Medicinal Chemistry 2023
Authors: Gehringer Matthias , Pape Felix , Méndez María , Barbie Philipp , Unzue Lopez Andrea , Lefranc Julien , Klingler Franca‐Maria , Hessler Gerhard , Langer Thierry , Diamanti Eleonora , Schiedel Matthias
Published: July 2023

The Frontiers in Medicinal Chemistry (FiMC) is the largest international Medicinal Chemistry conference in the German speaking area and took place from April 3rd to 5th 2023 in Vienna (Austria). Fortunately, after being cancelled in 2020 and two years (2021–2022) of entirely virtual meetings, due to the COVID‐19 pandemic, the FiMC could be held in a face‐to‐face format again. Organized by the Division of Medicinal Chemistry of the German Chemical Society (GDCh), the Division of Pharmaceutical and Medicinal Chemistry of the German Pharmaceutical Society (DPhG), together with the Division of Medicinal Chemistry of the Austrian Chemical Society (GÖCH), the Austrian Pharmaceutical Society (ÖPhG), and a local organization committee from the University of Vienna headed by Thierry Langer, the meeting brought together 260 participants from 21 countries. The program included 38 lectures by leading scientists from industry and academia as well as early career investigators. Moreover, 102 posters were presented in two highly interactive poster sessions.
Stability of Hill's spherical vortex
Authors: Choi Kyudong
Published: July 2023

We study stability of a spherical vortex introduced by M. Hill in 1894, which is an explicit solution of the three‐dimensional incompressible Euler equations. The flow is axi‐symmetric with no swirl, the vortex core is simply a ball sliding on the axis of symmetry with a constant speed, and the vorticity in the core is proportional to the distance from the symmetry axis. We use the variational setting introduced by A. Friedman and B. Turkington (Trans. Amer. Math. Soc., 1981), which produced a maximizer of the kinetic energy under constraints on vortex strength, impulse, and circulation. We match the set of maximizers with the Hill's vortex via the uniqueness result of C. Amick and L. Fraenkel (Arch. Rational Mech. Anal., 1986). The matching process is done by an approximation near exceptional points (so‐called metrical boundary points) of the vortex core. As a consequence, the stability up to a translation is obtained by using a concentrated compactness method.
Sponge‐phase Lipid Droplets as Synthetic Organelles: An Ultrafast Study of Hydrogen Bonding and Interfacial Environments
Authors: Xu Cong , Fracassi Alessandro , Baryiames Christopher P. , Bhattacharya Ahanjit , Devaraj Neal K. , Baiz Carlos R.
Published: July 2023

Bottom‐up design of biomimetic organelles has gained recent attention as a route towards understanding the transition between non‐living matter and life. Despite various artificial lipid membranes being developed, the specific relations between lipid structure, composition, interfacial properties, and morphology are not currently understood. Sponge‐phase droplets contain dense, nonlamellar lipid bilayer networks that capture the complexities of the endoplasmic reticulum (ER), making them ideal artificial models of such organelles. Here, we combine ultrafast two‐dimensional infrared (2D IR) spectroscopy and molecular dynamics simulations to investigate the interfacial H‐bond networks in sponge‐phase droplets composed of glycolipid and nonionic detergents. In the sponge phase, the interfacial environments are more hydrated and water molecules confined to the nanometer‐scale aqueous channels in the sponge phase exhibit dynamics that are significantly slower compared to bulk water. Surfactant configurations and microscopic phase separation play a dominant role in determining membrane curvature and slow dynamics observed in the sponge phase. The studies suggest that H‐bond networks within the nanometer‐scale channels are disrupted not only by confinement but also by the interactions of surfactants, which extend 1–2 nm from the bilayer surface. The results provide a molecular‐level description for controlling phase and morphology in the design of synthetic lipid organelles.
Transneuronal Circuit Analysis with Pseudorabies Viruses
Authors: Engel Esteban A. , Card J. Patrick , Enquist Lynn W.
Published: July 2023

Our ability to understand the function of the nervous system is dependent upon defining the connections of its constituent neurons. Development of methods to define connections within neural networks has always been a growth industry in the neurosciences. Transneuronal spread of neurotropic viruses currently represents the best means of defining synaptic connections within neural networks. The method exploits the ability of viruses to invade neurons, replicate, and spread through the intimate synaptic connections that enable communication among neurons. Since the method was first introduced in the 1970s, it has benefited from an increased understanding of the virus life cycle, the function of viral genomes, and the ability to manipulate the viral genome in support of directional spread of virus and the expression of transgenes. In this article, we review these advances in viral tracing technology and the ways in which they may be applied for functional dissection of neural networks. © 2023 The Authors. Current Protocols published by Wiley Periodicals LLC.

Basic Protocol 1: Retrograde infection of CNS circuits by peripheral injection of virus

Basic Protocol 2: Transneuronal analysis by intracerebral injection

Alternate Protocol 1: Transneuronal analysis with multiple recombinant strains

Alternate Protocol 2: Conditional replication and spread of PRV

Alternate Protocol 3: Conditional reporters of PRV infection and spread

Alternate Protocol 4: Reporters of neural activity in polysynaptic circuits

Support Protocol 1: Growing and titering a PRV viral stock

Support Protocol 2: Immunohistochemical processing and detection

Support Protocol 3: Dual‐immunofluorescence localization
Systematic Approach to Constructing Safe and High‐Performance Supercapacitors with Nonflammable Electrolytes
Authors: Van T. Nguyen Hoai , Lee Kyung‐Koo
Published: July 2023

The successful implementation of supercapacitors in large‐scale applications necessitates careful consideration of safety aspects, along with factors such as energy density, power density, working voltage, and cycling performance. One effective method for ensuring safety is the utilization of nonflammable trimethyl phosphate (TMP) electrolyte in supercapacitors. However, this approach suffers from the drawback of low power density due to its low ionic conductivity. To overcome this limitation, we propose the addition of co‐solvents, namely propylene carbonate, acetonitrile, and propionitrile (PN), to enhance limited electrochemical properties of TMP‐based electrolytes. We systematically investigate the impact of incorporating TMP into various organic solvents on physical and electrochemical properties. Binary electrolytes show improved ionic conductivity, capacitance, power density, energy density, and working voltage compared to the single TMP‐based electrolyte. Notably, our result highlights that the carbon‐based supercapacitors using TMP‐PN with 70 : 30 volume ratio electrolyte provide the best compromise between ionic conductivity (13.5 mS cm−1), capacitance (24.0 F g−1), energy density (13.2 Wh kg−1), power density (2.3 kW kg−1), working voltage (3.5 V), and safety. By combining the nonflammable properties of TMP with co‐solvents, we can overcome the trade‐off between safety and electrochemical performances, presenting advancement in the development of supercapacitors for energy storage applications.
Silver Supported Nanoparticles on [Mg4Al‐LDH] as an Efficient Catalyst for the α‐Alkylation of Nitriles, Oxindoles and Other Carboxylic Acid Derivatives with Alcohols
Authors: Izquierdo‐Aranda Luis , Adam Rosa , Cabrero‐Antonino Jose R.
Published: July 2023

An efficient heterogeneous silver‐catalyzed α‐alkylation of nitriles and oxindoles using alcohols via borrowing hydrogen strategy has been developed for the first time. The active nanostructured material, namely [Ag/Mg4Al‐LDH], composed by silver nanoparticles (3‐4 nm average particle size) homogeneously stabilized onto a [Mg4Al‐LDH] support with suitable Brønsted basic properties, constitutes a stable catalyst for the sustainable building of novel C−C bonds from alcohols and C‐nucleophiles. By applying this catalyst, a broad range of α‐functionalized nitriles and oxindoles has been accessed with good to excellent isolated yields and without the addition of external bases. Moreover, the novel silver nanocatalyst has also demonstrated its successful application to the cyclization of N‐[2‐(hydroxymethyl)phenyl]‐2‐phenylacetamides to afford 3‐arylquinolin‐2(1H)‐ones, through a one‐pot dehydrogenation and intramolecular α‐alkylation. Control experiments, kinetic studies, and characterization data of a variety of [Ag/LDH]‐type materials confirmed the silver role in the dehydrogenation and hydrogenation steps, while [Mg4Al‐LDH] matrix is able to catalyze condensation. Interestingly, these studies suggest as key point for the successful activity of [Ag/Mg4Al‐LDH], in comparison with other [Ag/LDH]‐type nanocatalysts, the suitable acid‐base properties of this material.
Consummate change agent
Authors: Elfman Lois
Published: July 2023

In April, Rev. Dr. LaKeesha Walrond, the first Black female president of New York Theological Seminary (NYTS), was honored by U.S. Department of Health and Human Services Secretary Xavier Becerra at the agency's Women on the Frontlines: Celebrating Women Faith Leaders event. Her work and personal mission centers on social justice and inclusion.
Synthesis and structure determination of a synthetic cannabinoid CUMYL‐THPINACA metabolite with differentiation between the ortho‐, meta‐, and para‐hydroxyl positions of the cumyl moiety
Authors: Azuma Yuki , Doi Takahiro , Asada Akiko , Tanaka Misa , Tagami Takaomi
Published: July 2023

Synthetic cannabinoids, a type of new psychoactive substances, are likely to be rapidly metabolized; thus, the detection of their metabolites, rather than the parent compound, is a common method used to prove drug consumption. Although the analysis of metabolites is generally performed by mass spectrometry, it is limited to structural estimation because of few commercially available standards. In particular, distinguishing between positional isomers is difficult. Synthetic cannabinoids with a cumyl moiety can be hydroxylated at the cumyl moiety during metabolism, but it remains unclear whether the hydroxylation occurs at the ortho, meta, or para position. This study determined the structures of a metabolite formed by mono‐hydroxylation at the cumyl moiety of the synthetic cannabinoid CUMYL‐THPINACA, used as a model compound. Chemical synthesis was performed to create possible metabolites with one hydroxyl group at the ortho, meta, or para positions of the cumyl moiety. Using the synthesized metabolites and liquid chromatography‐quadrupole time‐of‐flight mass spectrometry, the metabolite detected in the microsomal reaction of CUMYL‐THPINACA was identified as a compound mono‐hydroxylated at the para position based on retention time and product ion spectra. Moreover, the rapid metabolism of CUMYL‐THPINACA was demonstrated with an in vitro half‐life of 4.9 min and the identified metabolite could be detected for a relatively long time in vitro. The synthesized metabolite may be utilized as a good reference standard for proof of CUMYL‐THPINACA consumption. These findings have potential applications in the synthesis of metabolites of other synthetic cannabinoids bearing a cumyl moiety.
Environmental drivers of tropical forest snake phenology: Insights from citizen science
Authors: Jesus Letízia M. G. , Guedes Jhonny J. M. , Moura Mario R. , Feio Renato N. , Costa Henrique C.
Published: July 2023

Museum specimens and citizen science initiatives are valuable sources of information on how anthropogenic activities affect biodiversity and how species respond to rapid global change. Although tropical regions harbor most of the planet's biodiversity, investigations on species' phenological changes are heavily biased toward temperate regions. Such unevenness in phenological research is also taxonomically biased, with reptiles being the least studied group among tetrapod species regarding animal phenology. Herein, we used long‐term time‐series data to investigate environmentally driven changes in the activity pattern of tropical forest snakes. We gathered natural history collection and citizen science data for 25 snake species (five venomous and 20 non‐venomous) from an Atlantic Forest region in southeastern Brazil. Using circular mixed‐effects models, we investigate whether snake activity patterns followed the variation in environmental variables over a decade. Our results show that the activity pattern of Atlantic Forest snakes was seasonal and largely driven by average temperature and relative humidity. Since snakes are ectothermic animals, they are particularly sensitive to temperature variations, especially at small scales. Moreover, relative humidity can affect snake's seasonal activities through physiological constraints and/or prey availability. Most specimens were registered during the rainy season, with highly venomous snakes (lanceheads and coral snakes) emerging as the most abundant taxa. We highlight the importance of citizen science and natural history collections in better understanding biodiversity. Furthermore, our data obtained from local collectors underscore the need for environmental education programs and collaboration between researchers and local decision‐makers to raise awareness and reduce conflicts between people and snakes in the region.
Diverse Reactivity of a Ca(I) Synthon
Authors: Mai Jonathan , Rösch Bastian , Langer Jens , Grams Samuel , Morasch Michael , Harder Sjoerd
Published: July 2023

Low‐valent MgI complexes like (BDI)Mg−Mg(BDI) have found wide‐spread application as specialty reducing agents (BDI=β‐diketiminate). Also their redox reactivity was extensively investigated. In contrast, attempts to isolate similar CaI complexes led to reduction of the aromatic solvents or N2. Complex (DIPePBDI)Ca(μ6,μ6‐C6H6)Ca(DIPePBDI) (VIII) should be regarded a CaII complex with a bridging C6H62− dianion (DIPePBDI=HC[C(Me)N‐DIPeP]2, DIPeP=2,6‐C(H)Et2‐phenyl). It can react as a CaI synthon by releasing benzene and two electrons. Herein we describe the reactivity of VIII with benzene, biphenyl, naphthalene, anthracene, COT, Ph3SiCl, PhSiH3, a (BDI)AlI2 complex, H2, PhX (X=F, Cl, Br, I), tBuOH and tBuCH2I. The C6H62− dianion in VIII can react as a 2e− source, a nucleophile or a Brønsted base. In some cases radical reactivity cannot be excluded. Crystal structures of (DIPePBDI)Ca(μ8,μ8‐COT)Ca(DIPePBDI) (1) and [(DIPePBDI)CaX ⋅ (THF)]2 (X=F, Cl, Br, I) (2–5) are described.
Biotransformations with Imine Reductases: Design of a Practical Process Avoiding an Extractive Work‐Up by Entrapment of Water and Enzymes in an Immobilized Phase
Authors: Nastke Alina , Gröger Harald
Published: July 2023

A process concept for the asymmetric biocatalytic reduction of heterocyclic imines addressing the efficiency of the reaction as well as downstream‐processing steps was studied by utilizing a “heterogenized aqueous phase”, which contains the needed enzymes and cofactor within a superabsorber (polyacrylate) network, for the biotransformation. The immobilized biocatalytic system, which comprises an imine reductase (IRED), NADPH and an alcohol dehydrogenase for cofactor‐recycling, enables to run the reaction in pure organic medium. Thus, instead of an extractive work‐up as typical solution for biotransformations in aqueous medium, which, however, can be tedious due formation of emulsions, this type of IRED‐catalyzed process leads to a simplified work‐up consisting only of a decantation of the liquid organic reaction medium with the product from the heterogenized aqueous biocatalyst system. Exemplified for the (R)‐enantioselective reduction of 1‐methyl‐3,4‐dihydroisoquinoline by the IRED of Streptomyces viridochromogenes as a model reaction, a process was developed leading to 98 % conversion, 88 % yield and >99 % ee at a substrate concentration of 40 mM.
Lateral Deprotometallation‐Trapping Reactions on Methylated Pyridines, Quinolines and Quinoxalines Using Lithium Diethylamide
Authors: Hasyeoui Mohamed , Chapple Peter M. , Lassagne Frédéric , Roisnel Thierry , Cordier Marie , Samarat Ali , Sarazin Yann , Mongin Florence
Published: July 2023

The functionalization of methylated azines and diazines has aroused the interest of chemists given the structural diversity that it affords. Hindered lithium dialkylamides have been used to deprotometallate these substrates chemoselectively. In contrast, it can be observed that, despite some promising work, lithium diethylamide has been used very little for this purpose. Our objective here is on the one hand to make an inventory of what reagents have been used to deprotometallate methylpyridines, ‐quinolines and ‐quinoxalines, and on the other hand to describe the results obtained by seeking to functionalize a series of substrates with lithium diethylamide (picolines, 2,4‐lutidine, methylquinolines and 2‐methylquinoxaline). Our efforts to take advantage of the use of an in‐situ trap (a zinc chloride chelate) in these reactions are also described.
An electrochemical biosensor for the determination of hormone Human Chorionic Gonadotropin (hCG) in human serum
Authors: Koterwa Adrian , Bojko Magdalena , Ryl Jacek , Łukaszuk Krzysztof , Kozłowska Kornelia , Sieklicki Wiktor , Rodziewicz‐Motowidło Sylwia , Niedziałkowski Paweł
Published: July 2023

This work describes the modification of a gold electrode to create an electrochemical biosensor capable of detecting human chorionic gonadotropin (hCG). The biosensor was obtained by modifying the gold electrode with cysteamine and oligopeptide (PPLRINRHILTR). The modification steps of the gold electrode were confirmed by cyclic voltammetry (CV) and impedance electrochemical spectroscopy (EIS) measurements. The conducted EIS experiments in 0.01 M PBS, pH 7.4 confirm that the biosensor exhibits sensitivity towards hCG in a range of concentrations from 1×10−12 to 1×10−7 M (0.5 mIU/mL – 50 000 mIU/mL) to solutions with a detection limit of 1. 91×10−14 M (0.0095 mIU/mL). The effectiveness of the investigated biosensor was also investigated in human serum. The EIS comparative investigations were performed in human serum containing a concentration of 1×10−12 M (0.5 mIU/mL) hCG and in human serum where the hCG was added. The obtained results indicate that the investigated biosensor is selective for the presence of hCG hormone in the human serum.
Vancomycin sensing using a phenylboronic acid‐modified nanopore pipette
Authors: Sato Fumiya , Nakano Haruka , Kamijo Toshio , Watanabe Kazuhiro , Fujimura Tsutomu , Takahashi Yasufumi , Sato Katsuhiko
Published: July 2023

Nanopore sensing measures the changes in charge and physical state around the nanopores as changes in ionic current. In this study, we performed vancomycin (VCM) sensing with nanopores modified via Au−S bonds with dithiobis(4‐butyrylamino‐m‐phenylboronic acid) (DTBA‐PBA), a derivative of phenylboronic acid (PBA) bearing a thiol. First, we modified a 3‐mm‐diameter Au electrode with a DTBA‐PBA self‐assembled monolayer (SAM) to confirm the VCM response of the PBA interface by cyclic voltammetry. DTBA‐PBA was then immobilized in the same manner on a nanopore pipette coated with an Au layer. We measured the VCM concentration from the change in ion current using the nanopore pipette. A VCM concentration‐dependent ionic current response was observed in the range of 0.01–1 mM. Many kinds of pharmaceuticals can bind to PBA; therefore, this method could be used for quick, easy, in situ quantification of not only VCM but also other pharmaceuticals with serious side effects.
A tooth crown morphology framework for interpreting the diversity of primate dentitions
Authors: Chapple Simon A. , Skinner Matthew M.
Published: July 2023

Variation in tooth crown morphology plays a crucial role in species diagnoses, phylogenetic inference, and the reconstruction of the evolutionary history of the primate clade. While a growing number of studies have identified developmental mechanisms linked to tooth size and cusp patterning in mammalian crown morphology, it is unclear (1) to what degree these are applicable across primates and (2) which additional developmental mechanisms should be recognized as playing important roles in odontogenesis. From detailed observations of lower molar enamel–dentine junction morphology from taxa representing the major primate clades, we outline multiple phylogenetic and developmental components responsible for crown patterning, and formulate a tooth crown morphology framework for the holistic interpretation of primate crown morphology. We suggest that adopting this framework is crucial for the characterization of tooth morphology in studies of dental development, discrete trait analysis, and systematics.
Influence of cultivation practices on the metabolism of cytokinin and its correlation in rice production
Authors: Shah Saud , Cai Lijuan , Li Xiuling , Fahad Shah , Wang Depeng
Published: July 2023

Cytokinin (CTK) has an important regulatory effect on plant morphology, physiology, and yield, and is one of the main factors regulating nitrogen absorption, transport, and metabolism. This paper reviews the research progress in nitrogen absorption, transport and metabolism, cytokinin synthesis, transport and signal transduction, etc., focusing on the physiological mechanisms by which CTK and nitrogen collaborate to regulate the root–shoot relationship and its impact on agronomic traits of crops. The synthesis of trans‐zeatin (tZ) and trans‐zeatin riboside (tZR) is generally regulated by root nitrogen, which is transported them to the sprouts, regulates nitrogen allocation and metabolism, and affects photosynthetic characteristics and yield. In young shoots, nitrogen upregulates the synthesis of isopentenyl, adenine (iP), and iP‐nucleoside (iPR) and transports to roots through the phloem, reducing nitrogen uptake and transport, affecting root morphology. Based on this, the role of, CTK in coordinating relationships between source repositories and enhancing injection. We conducted an analysis on how various cultivation methods impact CTK metabolism and its relationship with plant growth. Additionally, we discussed the challenges associated with applying CTK functions to paddy field production and suggested future research directions.
The role of dietary polyphenols in the control of chronic noncommunicable diseases
Authors: Armas Díaz Yasmany , Ferreiro Cotorruelo Maria Soledad , Battino Maurizio
Published: July 2023

Noncommunicable chronic diseases (NCDs) are among the leading causes of death and disability worldwide. The most common NCDs are cancer, obesity, cardiovascular diseases, and diabetes. Nowadays, they represent one of the greatest challenges health systems face worldwide. The increase in the consumption of polyphenol‐rich foods could contribute to the reduction of these pathologies, due to their antioxidant, anti‐inflammatory, anticancer, immunomodulatory, and cardiovascular protective properties, among others. This review aims to highlight some studies carried out in recent years to enhance the possible benefits of a diet rich in polyphenols in the prevention or treatment of NCDs.
Effects of isoflavone and probiotic intake on calcium transport and bone metabolism biomarkers in female rats
Authors: Harahap Iskandar Azmy , Kuligowski Maciej , Schmidt Marcin , Kołodziejski Paweł A. , Suliburska Joanna
Published: July 2023

Calcium is essential for maintaining bone health as it contributes to bone formation, remodeling, strength, and density. This study investigated the effect of isoflavones and probiotics on calcium transporters' gene expression, serum calcium levels, and bone metabolism biomarkers in healthy female rats. Forty‐eight female Wistar rats were classified into six groups. Bone metabolism biomarkers (pyridinoline, deoxypyridinoline, parathyroid hormone, and osteocalcin) and serum calcium levels were measured by enzyme‐linked immunosorbent assay (ELISA) and atomic absorption spectroscopy (AAS), respectively. Gene expression of calcium transporters (Trpv5 and Trpv6) was evaluated in duodenum and jejunum tissue samples using quantitative polymerase chain reaction (qPCR). Trpv5 and Trpv6, epithelial calcium channels, play a crucial role in calcium transport and homeostasis in the body. The study consisted of a1‐week adaptation period for the rats to adjust to the controlled conditions, followed by an 8‐week intervention phase. The daidzein and genistein group showed a significant increase in the gene expression of the Trpv6 transporter in the duodenum and a marked decrease in serum pyridinoline levels compared to the control group. The tempeh and soybean groups showed a significant decrease in the gene expression of the Trpv5 calcium transporter in the jejunum. However, no significant influence of the Lactobacillus acidophilus diet on calcium transport and bone metabolism biomarkers was observed in the L. acidophilus group. The correlation analysis showed a significant positive relationship between serum calcium, bone metabolism biomarkers, and calcium transporters. In conclusion, our study demonstrates that the daidzein and genistein diet improves calcium transport in the duodenum and reduces pyridinoline serum concentrations, while tempeh and soybean diets reduce calcium transport in the jejunum. However, the combination of daidzein, genistein, and L. acidophilus did not demonstrate a synergistic effect on calcium transport and bone metabolism, suggesting that further investigations are needed to elucidate their potential interactions.
Exploring access to community care and emergency department use among people with dementia: A qualitative interview study with people with dementia, and current and bereaved caregivers
Authors: Williamson Lesley E. , Sleeman Katherine E. , Evans Catherine J.
Published: July 2023

Objectives

Emergency department (ED) attendance is common among people with dementia and associated with poor health outcomes. Literature suggests a link between access to community care and the ED, but we know little about the mechanisms behind this link. This study aimed to explore experiences of accessing community and emergency care among people affected by dementia.

Methods

Informed by critical realism, semi‐structured online and telephone interviews were conducted with people with dementia and family caregivers, with and without experience of using the ED. Participants were recruited from across the United Kingdom using purposive sampling with maximum variation. A mostly experiential reflexive thematic analysis approach was used, applying the candidacy model of access to deepen interpretation.

Results

Two dyad and 33 individual interviews were conducted with 10 people with dementia, 11 current caregivers and 16 bereaved caregivers (men = 11, 70–89 years = 18, white ethnicity = 32). Three themes are reported: (1) Navigating a ‘push system’, (2) ED as the ‘last resort’, and (3) Taking dementia ‘seriously’. Themes describe a discrepancy between the configuration of services and the needs of people affected by dementia, who resort to the ED in the absence of accessible alternatives. Underlying this discrepancy is a lack of systemic prioritisation of dementia and wider societal stigma.

Conclusion

Although a last resort, ED attendance is frequently the path of least resistance for people with dementia who encounter multiple barriers for timely, responsive access to community health and social care. Greater systemic prioritisation of dementia as a life‐limiting condition may help to reduce reliance on the ED through essential development of post‐diagnostic care, from diagnosis to the end of life.
Improving the quality of family planning services in the Philippines: Barriers and opportunities
Authors: Trisolini Michael , Javier Ma. Elena , Jabar Melvin , Rodriguez Cristina , Varquez Jessie , Danganan Omega Diadem , Benabaye Rosario Marilyn , Reynaldo Chris‐Angelo , Conti‐Lopez Mary Angeli , Dela Rosa Jose Juan , Mendoza Ophelia , Dasmarinas Easter , Stan Laurentiu , Bisson Cristina , Oliveros Yolanda
Published: July 2023

We conducted qualitative research with family planning clients, potential clients, and service providers on barriers and opportunities for improving the quality of family planning services in the Philippines. The family planning service providers included the primary, secondary, and tertiary levels of the health system. Our goal was to aid in developing more effective family planning quality improvement (QI) programs. Our methods included focus groups, key informant interviews and thematic content analysis of the qualitative data. We found four themes: the components of quality of family planning care; factors influencing quality; challenges for improving quality; and provider bias in the types of family planning services offered to clients. We identified five implications for QI, including: reduce provider bias; level off the understanding of QI concepts and roles among the different family planning service providers; involve men more actively; design new digital communication strategies for reaching clients and potential clients; and explore collaborations with private sector pharmacies. The findings from this study can guide the development of a pilot family planning QI programme in the Philippines. The findings provide themes and practical insights for an intervention‐focused theory of change on how to improve current programs, design new programs, be more responsive to the needs and concerns of clients and potential clients and be well‐accepted and sustained by providers. This can lay the groundwork for improving family planning outcomes and reducing teenage pregnancy rates and the unmet need for family planning throughout the Philippines.
An assessment of token value and effectiveness: A replication
Authors: Hangen Marcella M. , Romero Ashley N. , Norris Halle M. , Gorycki Kathryn A. , Roberts Breanna R. , Neidert Pamela L.
Published: July 2023

The purpose of the current study was to conduct a systematic replication of Fiske et al. (2015) to extend the behavior‐analytic literature on token reinforcement. Specifically, the researchers addressed several of the limitations of Fiske et al. by including specific conditioning procedures, creating a controlled history of reinforcement with the token system, including participants with and without disabilities to extend the generality of the findings, and equating the magnitude of reinforcement across the primary and paired‐token conditions. The current study evaluated the reinforcing value of tokens by using progressive‐ratio schedules to compare the efficacy of primary reinforcement, paired tokens, and unpaired tokens. The results suggest that paired tokens may function as reinforcers, but they were not as consistently effective as primary reinforcers.