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The article announces the winners of the Molecules Best Paper Award 2013 in the U.S., including Thomas J. Schmidt, Reto Brun, and Holger Trojan.

Integrating multi-stimuli response properties in one molecule is challenging. This study presents two 2D polymers, [(Bpydp)Ln(H2O)(BDC)]·NO3·2H2O (Ln = Eu(1), Tb(2)), exhibiting rapid photo-responsiveness and the ability to detect specific small-molecule amines. In particular, complex 1 combines the functions of inkless printing, amine detection, anti-counterfeiting, and fluorescence recognition. [ABSTRACT FROM AUTHOR]

In this paper, we present the synthesis of four new complexes: the dimeric precursor [Ir(dmppz)2(μ-Cl)]2 (1) (Hdmppz -- 3,5-dimethyl-1-phenyl-1H-pyrazole) and heteroleptic bis-cyclometalated complexes: [Ir(dmppz)2(Py2CO)]PF6•½CH2Cl2 (2), [Ir(dmppz)2(H2biim)]PF6•H2O (3), and [Ir(dmppz)2(PyBIm)]PF6 (4), with auxiliary N,N-donor ligands: 2-di(pyridyl)ketone (Py2CO), 2,2'-biimidazole (H2biim) and 2-(2'-pyridyl)benzimidazole (PyBIm). In the obtained complexes, SC-X-ray analysis revealed that Ir(III) has an octahedral coordination sphere with chromophores of the type {IrN2C2Cl2} (1) or {IrN4C2} (2-4). The complexes obtained, which have been fully characterised by physicochemical methods (CHN, TG, FTIR, UV-Vis, PL and ¹H, 13C, 15N NMR), were used to continue our studies on the factors influencing the cytotoxic properties of potential chemotherapeutic agents (in vitro). To this end, the following studies are presented: (i) comparative analysis of the effects on the biological properties of N,N-donor ligands and C,N-donor ligands in the studied complexes, (ii) studies of the interactions of the compounds with the selected molecular target: DNA and BSA (UV-Vis, CD and PL methods), (iii) and the reactivity towards redox molecules: GSH, NADH (UV-Vis and/or ESI-MS methods), (iv) cytotoxic activity (IC50) of potential chemotherapeutics against MCF-7, K-562 and CCRF-CEM cell lines. [ABSTRACT FROM AUTHOR]

The article focuses on a physical model designed for beginning students to help them understand the classification system for matter. The model is constructed using two large reclosable plastic bags for each student. Each large plastic bag contains eight smaller reclosable bags. Each small bag contains an assortment of colored vinyl-coated paper clips, some of which are attached to each other in specific ways as described. The larger bags can be labeled as set I and set II, with the smaller bags being labeled A through H. It is easier for the students to organize their work if the two sets of bags are labeled using different colors. The model helps students to build accurate conceptual pictures of what constitutes molecules, compounds, mixtures, and pure substances.

The suggestion that the paper by Naef and Acree is the first one with the capability to treat "any molecule under the sun" is simply totally incorrect. In Ref. [[7]] (Neaf and Acree), reference to GC methods are only the previous publications by Naef and Acree. 10.3390/molecules25051147 7 Naef R., Acree W.E. Jr. Calculation of the Vapour Pressure of Organic Molecules by Means of a Group-Additivity Method and their Resultant Gibbs Free Energy and Entropy of Vaporization at 298.15 K. References 1 Naef R., Acree W.E. Jr. Revision and Extension of a Generally Applicable Group-Additivity Method for the Calculation of the Standard Heat of Combustion and Formation of Organic Molecules. [Extracted from the article]

The strong interaction between water molecules and graphene oxide (GO) enables moisture‐responsive graphene actuators, revealing great potential for soft robots. However, current strategies for developing smart graphene actuators fail to tailor their material property gradient in a controlled manner, and the driving manner is usually limited to single stimulus actuation. Here, a facile preparation of humidity/thermal/light multiresponsive graphene actuators by sequential vacuum filtration of GO and reduced GO (RGO) aqueous solutions is reported. The photoreduction degree of RGO layer is tuned precisely beforehand by changing ultraviolet (UV) light irradiation time, and thus a pretailored reduction gradient along the normal direction of the GO/RGO bilayer paper would form in a highly controlled manner. Taking advantage of the competitive water adsorption between the GO and RGO layers, as well as the thermal‐, light‐promoted desorption, the GO/RGO bilayers deform in response to moisture, light, and temperature changes; and the deformation degree can be modulated by controlling the gradient of oxygen‐containing groups (OCGs). As a proof of principle, a humidity‐responsive graphene mimosa and a humidity/thermal/light multiresponsive graphene actuators are fabricated. The GO/RGO bilayer paper with pretailored reduction gradient holds great promise for easy fabrication of biomimetic actuators that enable performing predictable deformation. Humidity/thermal/light multiresponsive graphene actuators are prepared by sequential vacuum filtration of graphene oxide (GO) and reduced GO (RGO) with a pretailored reduction gradient. GO/RGO bilayer actuators with tunable curving performance are achieved by controlling the photoreduction degree. Humidity responsive mimosa and multiresponsive paper robot are designed based on the competitive water adsorption between GO/RGO layers and the thermal‐, light‐promoted water desorption. [ABSTRACT FROM AUTHOR]

The article reports that this issue of the journal introduces a revised list of sections and subsections, designed in close collaboration with the whole editorial board. The aim of these modifications is to reflect more faithfully the wide diversity of activities covered by the journal. A new section has been introduced as "Atomic and Molecular Collisions", it covers a large range of activities, from atom/atom or atom/molecules collisions including the very active field of ultra-cold collisions in laser-cooled atomic or molecular gases, to electron scattering and molecular reactivity.

The present comment concerns some doubtful results included in the above papers. [ABSTRACT FROM AUTHOR]

Boron-contained molecular capsules triggered by amines are described for the first time; when Et3N was employed as a chemical stimulus the Lewis acid Et3NH+, produced by solvolysis reaction on the boron, was found to be encapsulated in the internal cavity, whereas use of nBu3N led to the related dynamic capsule capable of accommodating several guest species including Cs+. [ABSTRACT FROM AUTHOR]

Precise manipulation of individual DNA molecules entering and leaving the channel ports, as well as their smooth passage across the channel, is essential for the detection and screening of DNA molecules using nano-/micro-fluidic technologies. In this paper, by combining single-molecule fluorescence imaging and numerical simulations, the motion states of DNA molecules translocating through a microfluidic channel under the action of the applied electric field are monitored and analyzed in detail. It is found that, under certain conditions of the applied electric field DNA molecules exhibit various motion states, including translation crossing, deflection outflow, reverse outflow, reciprocal movement, and elliptical movement. Simulations indicate that, under the action of Saffman force, DNA molecules can only undergo deflective motion when they experience a velocity gradient in the microchannel flow field; and they can only undergo elliptical motion when their deflective motion is accompanied by a spin motion. In this case, the Magnus force also plays an important role. The detailed study and elucidation of the movement states, dynamic characteristics and mechanisms of DNA molecules such as the deflective and elliptical motions under the actions of Saffman and Magnus forces have helpful implications for the development of related DNA/gene nano-/microfluidic chips, and for the separation, screening and detection of DNA molecules. [ABSTRACT FROM AUTHOR]

A database of thermally activated delayed fluorescent (TADF) molecules was automatically generated from the scientific literature. It consists of 25,482 data records with an overall precision of 82%. Among these, 5,349 records have chemical names in the form of SMILES strings which are represented with 91% accuracy; these are grouped in a subsidiary database. Each data record contains one of the following four properties: maximum emission wavelength (λEM), photoluminescence quantum yield (PLQY), singlet-triplet energy splitting (ΔEST), and delayed lifetime (τD). The databases were created through text mining using ChemDataExtractor, a chemistry-aware natural-language-processing toolkit, which has been adapted for TADF research. The text-mined corpus consisted of 2,733 papers from the Royal Society of Chemistry and Elsevier. To the best of our knowledge, these databases are the first databases that have been auto-generated for TADF molecules from existing publications. The databases have been publicly released for experimental and computational applications in the TADF research field. [ABSTRACT FROM AUTHOR]

Heritage guidelines recognize odors as a value associated with a place. This study aims to clarify the connection between heritage and volatile organic compounds at the molecular level. At variance with previous studies, usually focused only on book‐related compounds from accelerated degradation tests, the whole air of one of the most significant historical libraries in Italy was studied. A sampling of the volatiles off‐gassing from the two most iconic rooms, respectively open and forbidden to visitors, was performed via a non‐invasive, nondestructive green method, solid‐phase‐micro‐extraction. The gas‐chromatographic analyses resulted in the appraisal of olfactory contributions from books, storage environment, and, for the first time, anthropic activities and pollution.Concerning the paper decay process, for the very first time, the presence of 2‐ethyl‐1‐hexanol in the chromatographic signature of the library air is rationalized according to the Guerbet reaction. The presence of all other compounds is explained by the paper decay process, anthropic sources, and pollution. Indoor air comprises analytes related to paper decay, identified by previous studies, and additional compounds never found before.Most volatile compounds are aliphatic and aromatic hydrocarbons, aldehydes, alcohols, terpenes, and terpenoids. Odor contributions from a selected number of analytes were pinpointed. Alkanes dominate the volatiles chromatographic signature, and impart a slight hydrocarbon smell. Aromatics supplement their characteristic aromatic odor. Aldehydes' very low odor threshold makes them strongly contribute to both fruity and fatty descriptors. Benzaldehyde, furfural, vanillin, and camphor add, respectively, an hint of almond, bread, vanilla, and camphor. Alcohols such as 2‐ethyl hexanol have a floral scent. Wood‐related terpenes and terpenoids contribute to the woody smell of the library.The digital molecular fingerprint of the "scent of knowledge" enables documentation, conservation, and future chemical reproduction of the historical library odor. [ABSTRACT FROM AUTHOR]

The bent structure of the water molecule, and its hydrogen‐bonding properties, arguably rank among the most impactful discoveries in the history of chemistry. Although the fact that the H—O—H angle must deviate from linearity was inferred early in the 20th century, notably from the existence of the electric dipole moment, it was not clear what that angle should be and why. One hundred years ago, a young PhD student at the University of California, Berkeley, Eustace J. Cuy, rationalized the V‐shape structure of a water molecule using the Lewis theory of a chemical bond, i.e. a shared electron pair, and its tetrahedral stereochemistry. He was inspired, in part, by the proposal of a weak (hydrogen) bond in water by two colleagues at Berkeley, Wendell Latimer and Worth Rodebush, who published their classic paper a year earlier. Cuy went on to suggest that other molecules, notably H2S and NH3, have similar structures, and presciently predicted that this architecture has broader consequences for the structure of water as a liquid. This short, but brilliant paper has been completely forgotten, perhaps due to the tragic death of the author at the age of 28; the hydrogen‐bond study is also rarely recognized. One of the most impactful publications on the structure of liquid water, a classic treatise published in 1933 by John Bernal and Ralph Fowler, does not mention either of the two pioneering papers. In this essay, the background for the two discoveries is described, including the brief history of Lewis's research on the nature of the chemical bond, and the history of the discovery of the hydrogen bond, which inspired Cuy to look at the structure of the water molecule. This is – to the best of the author's knowledge – the first biographical sketch of Eustace J. Cuy. [ABSTRACT FROM AUTHOR]

Abstract: Our understanding of the underlying mechanisms of Ca2+ signaling as well as our appreciation for its ubiquitous role in cellular processes has been rapidly advanced, in large part, due to the development of fluorescent Ca2+ indicators. In this chapter, we discuss some of the most common chemical Ca2+ indicators that are widely used for the investigation of intracellular Ca2+ signaling. Advantages, limitations and relevant procedures will be presented for each dye including their spectral qualities, dissociation constants, chemical forms, loading methods and equipment for optimal imaging. Chemical indicators now available allow for intracellular Ca2+ detection over a very large range (<50nM to >50μM). High affinity indicators can be used to quantify Ca2+ levels in the cytosol while lower affinity indicators can be optimized for measuring Ca2+ in subcellular compartments with higher concentrations. Indicators can be classified into either single wavelength or ratiometric dyes. Both classes require specific lasers, filters, and/or detection methods that are dependent upon their spectral properties and both classes have advantages and limitations. Single wavelength indicators are generally very bright and optimal for Ca2+ detection when more than one fluorophore is being imaged. Ratiometric indicators can be calibrated very precisely and they minimize the most common problems associated with chemical Ca2+ indicators including uneven dye loading, leakage, photobleaching, and changes in cell volume. Recent technical advances that permit in vivo Ca2+ measurements will also be discussed. [Copyright &y& Elsevier]

Chemicals are a part of modern life. Products are the main emissions of the chemical and pharmaceutical industries. This makes it difficult to hold them back efficiently. Very often they do not become degraded or fully broken down to water, carbon dioxide and inorganic salts. Often, unknown transformation products are formed in the environment. Therefore, according to the principles of green chemistry, the functionality of a chemical should not only include the properties of a chemical necessary for its application, but also easy and fast degradability after its use. Taking into account the full life cycle of chemicals will lead to a different understanding of the functionality necessary for a chemical. In the present discussion, improvement of synthesis and renewable feedstock are very prominent, whereas the environmental properties of the molecules are somewhat underestimated. To stimulate the discussion about the future role of degradable chemicals several examples are presented to underline the feasibility and the economic potential of this approach, called benign by design. [ABSTRACT FROM AUTHOR]

The document titled "Advances in Amylases—What's Going on?" provides an overview of the classification and research on amylolytic enzymes, specifically α-amylases. It discusses the classification of α-amylase families within the CAZy database, highlighting GH13 and GH57 as the main families, and mentions the existence of subfamilies within GH13. The document also mentions a special issue of the journal Molecules, titled "Advances in Amylases," which includes thirteen papers covering various aspects of amylolytic enzymes. The papers discuss topics such as enzyme hydrolysis of starch granules, inactivation of α-amylase, protein content in rice flour, and the structure and function of different α-amylase subfamilies. The document concludes by expressing appreciation to the contributors and reviewers of the special issue. This article by Štefan Janeček explores the topic of molecules and their properties, providing an in-depth analysis of various types of molecules, their structures, functions, and interactions. It emphasizes the importance of understanding molecules in fields such as chemistry, biology, and medicine. The article is a valuable resource for library patrons conducting research on molecular science and its applications. [Extracted from the article]

We present in this paper the stability of SWCNT hybrid systems with Py molecules. vdW type interactions are therefore the main interaction mechanism between encapsulated molecules and nanotubes, and the simplest model to describe these interactions is the Lennard-Jones potential. We have therefore performed energy minimization calculations on hybrid SWCNTs in a very wide range of diameters and of all chirality using the Lennard-Jones potential. The structure of the carbon nanotube is obtained from the winding of graphene on itself to form a hollow cylinder described by the pair of integers (n, m) entirely determining its structural characteristics, while the optimization of the geometry of the Py molecule is obtained by SIESTA using the exchange–correlation functional LDA. After minimisation, an approach that combines density functional theory, molecular mechanics, bond polarizability model, and spectral moment's method has been used to compute Raman spectra. Two types of vibration modes of SWCNTs attract our attention. Initially, the modifications of the modes of Py after encapsulation will be analyzed. In the following discussion, we examine how the vibrational properties of single-walled carbon nanotubes (SWCNTs) are affected by encapsulation, specifically in relation to the RBM and tangential modes. Our analysis of the Raman active modes supports the notion that the structural integrity of the SWCNTs remains intact and indicates the occurrence of a charge transfer between the Py molecules and SWCNTs. This charge transfer depends on the geometric position of Py in the SWCNT. [ABSTRACT FROM AUTHOR]

A drug molecule is a substance that changes an organism's mental or physical state. Every approved drug has an indication, which refers to the therapeutic use of that drug for treating a particular medical condition. While the Large Language Model (LLM), a generative Artificial Intelligence (AI) technique, has recently demonstrated effectiveness in translating between molecules and their textual descriptions, there remains a gap in research regarding their application in facilitating the translation between drug molecules and indications (which describes the disease, condition or symptoms for which the drug is used), or vice versa. Addressing this challenge could greatly benefit the drug discovery process. The capability of generating a drug from a given indication would allow for the discovery of drugs targeting specific diseases or targets and ultimately provide patients with better treatments. In this paper, we first propose a new task, the translation between drug molecules and corresponding indications, and then test existing LLMs on this new task. Specifically, we consider nine variations of the T5 LLM and evaluate them on two public datasets obtained from ChEMBL and DrugBank. Our experiments show the early results of using LLMs for this task and provide a perspective on the state-of-the-art. We also emphasize the current limitations and discuss future work that has the potential to improve the performance on this task. The creation of molecules from indications, or vice versa, will allow for more efficient targeting of diseases and significantly reduce the cost of drug discovery, with the potential to revolutionize the field of drug discovery in the era of generative AI. [ABSTRACT FROM AUTHOR]

Radical-cation salts of formula β?-(BEDT-TTF)4[(H3O)Fe(C2O4)3]·guest have produced a large number of superconductors and provided a route to introduce magnetism and chirality into the same multifunctional material. A relationship has been found in these salts between the length of the b axis and the superconducting Tc. Increasing the b axis length by introducing larger guest molecules, such as benzonitrile and nitrobenzene, gives the highest superconducting Tcs in this family of salts. Smaller guests such as pyridine show no superconducting transition, whilst asymmetrical guests which are larger than nitrobenzene have given a different bilayered structure. Other potential guest molecules have been limited by their ability to be used as the solvent in which the crystals are grown via electrocrystallisation. This paper reports a method which introduces guest molecules into the crystal which are a solid or liquid additive within the crystal-growing solvent 1,2,4-trichlorobenzene:ethanol. We present the crystal structures of five new BEDT-TTF radical-cation salts with tris(oxalato)ferrate anions using guest molecules toluene, phenol, benzaldehyde, 4-bromobenzaldehyde, and kojic acid. [ABSTRACT FROM AUTHOR]

Medulloblastoma (MB) is a highly malignant childhood brain tumor. Group 3 MB (Gr3 MB) is considered to have the most metastatic potential, and tailored therapies for Gr3 MB are currently lacking. Gr3 MB is driven by PRUNE-1 amplification or overexpression. In this paper, we found that PRUNE-1 was transcriptionally regulated by lysine demethylase LSD1/KDM1A. This study aimed to investigate the therapeutic potential of inhibiting both PRUNE-1 and LSD1/KDM1A with the selective inhibitors AA7.1 and SP-2577, respectively. We found that the pharmacological inhibition had a substantial efficacy on targeting the metastatic axis driven by PRUNE-1 (PRUNE-1-OTX2-TGFβ-PTEN) in Gr3 MB. Using RNA seq transcriptomic feature data in Gr3 MB primary cells, we provide evidence that the combination of AA7.1 and SP-2577 positively affects neuronal commitment, confirmed by glial fibrillary acidic protein (GFAP)-positive differentiation and the inhibition of the cytotoxic components of the tumor microenvironment and the epithelial–mesenchymal transition (EMT) by the down-regulation of N-Cadherin protein expression. We also identified an impairing action on the mitochondrial metabolism and, consequently, oxidative phosphorylation, thus depriving tumors cells of an important source of energy. Furthermore, by overlapping the genomic mutational signatures through WES sequence analyses with RNA seq transcriptomic feature data, we propose in this paper that the combination of these two small molecules can be used in a second-line treatment in advanced therapeutics against Gr3 MB. Our study demonstrates that the usage of PRUNE-1 and LSD1/KDM1A inhibitors in combination represents a novel therapeutic approach for these highly aggressive metastatic MB tumors. [ABSTRACT FROM AUTHOR]

While a country-western song title may seem out of place in a I Molecules i Editorial, the words nevertheless seem most appropriate to define the journal's trajectory since volume 1 was published in 1996, to the occasion we now aim to celebrate with the Special Issue being announced herein. 1 Kulkarni B.A., Chattopadhyay S., Chattopadhyay A., Mamdapur V.R. Synthesis of the demospongic compounds, (6Z,11Z)-octadecadienoic acid and (6Z,11Z)-eicosadienoic acid. [Extracted from the article]

The paper presents the incorporation of in silico missenses and studies the effect of missenses to understand its effect on the ligand–protein interactions, of COVID-19 protein. In silico protein–ligand interaction, studies are being used to understand and investigate the drug-likeness of various molecules. 19 novel COVID-19 proteins are designed by inducing in silico missenses by mutating N691 amino acid residue in 7bv2 protein, the only residue forming H-bond with the ligand molecule in the parent protein. The work illustrates the effects of in silico-induced mutation on various interactions such as H-Bond, VDW, π-alkyl interactions, and changes in the number and type of surrounding amino acid residues. The results have suggested a common pattern of behaviour on mutation with T, V, W, and Y. Further, it is observed that the number and type of amino acid residues increase on mutation, suggesting the effect of mutation on the ligand–protein binding. [ABSTRACT FROM AUTHOR]

Laser desorption/ionization mass spectrometry (LDI-MS) techniques have emerged as powerful tools for analyzing compounds of natural and synthetic origins. However, conventional methods like matrix-assisted laser desorption/ionization (MALDI) often suffer from background signals and limited detection capabilities, particularly for low molecular weight compounds. Surface-assisted laser desorption/ionization (SALDI) methodologies, utilizing nanomaterials, have shown promise in overcoming these limitations. Gold nanoparticles (AuNPs) are among the most widely utilized nanomaterials in SALDI-MS applications. AuNPs offer several advantages over traditional MALDI matrices, such as reduced interference, internal calibration potential, and enhanced stability. They have been successfully employed for analyzing a diverse range of analytes, from low molecular weight (LMW) compounds to peptides, proteins, and biological entities. This paper provides a comprehensive overview of various synthesis methods, morphological properties, and comparisons with conventional MALDI matrices. Furthermore, it explores the application of AuNPs for analyzing LMW compounds and imaging various surfaces using LDI-MS techniques. [ABSTRACT FROM AUTHOR]

The central purpose of this paper is to explore the nonlinear dynamics of the (2+1)-dimensional Kadomtsev–Petviashvili equation (KPE). The multiple soliton solutions (MSSs) are constructed via applying the Hirota method. Then the soliton molecules on the (x , y) -, (x , t) - and (y , t) -planes are extracted via imposing the velocity resonance conditions to the MSSs. Eventually, two effective techniques, the sub-equation approach (SEA) and the variational approach (VA), are employed to probe some other diverse wave solutions, which are the bright wave, dark wave, singular wave and the singular periodic wave solutions. The dynamics of the extracted solutions are unveiled graphically to exhibit the physical attributes. The attained solutions in this paper can enlarge the exact solutions of the (2+1)-dimensional KPE and enable us to understand the nonlinear dynamic behaviors better. [ABSTRACT FROM AUTHOR]

Small molecules find extensive application in medicine, food safety, and environmental studies, particularly in biomedicine. Immunoassay technology, leveraging the specific recognition between antigens and antibodies, offers a superior alternative to traditional physical and chemical analysis methods. This approach allows for the rapid and accurate detection of small molecular compounds, owing to its high sensitivity, specificity, and swift analytical capabilities. However, small molecular compounds often struggle to effectively stimulate an immune response due to their low molecular weight, weak antigenicity, and limited antigenic epitopes. To overcome this, coupling small molecule compounds with macromolecular carriers to form complete antigens is typically required to induce specific antibodies in animals. Consequently, the preparation of small-molecule artificial antigens and the production of efficient specific antibodies are crucial for achieving precise immunoassays. This paper reviews recent advancements in small molecule antibody preparation technology, emphasizing the design and synthesis of haptens, the coupling of haptens with carriers, the purification and identification of artificial antigens, and the preparation of specific antibodies. Additionally, it evaluates the current technological shortcomings and limitations while projecting future trends in artificial antigen synthesis and antibody preparation technology. [ABSTRACT FROM AUTHOR]

Biophysical models can predict the behavior of cell cultures including 3D cell aggregates (3DCAs), thereby reducing the need for costly and time-consuming experiments. Specifically, mass transfer models enable studying the transport of nutrients, oxygen, signaling molecules, and drugs in 3DCA. These models require the defining of boundary conditions (BC) between the 3DCA and surrounding medium. However, accurately modeling the BC that relates the inner and outer boundary concentrations at the border between the 3DCA and the medium remains a challenge that this paper addresses using both theoretical and experimental methods. The provided biophysical analysis indicates that the concentration of molecules inside boundary is higher than that at the outer boundary, revealing an amplification factor that is confirmed by a particle-based simulator (PBS). Due to the amplification factor, the PBS confirms that when a 3DCA with a low concentration of target molecules is introduced to a culture medium with a higher concentration, the molecule concentration in the medium rapidly decreases. The theoretical model and PBS simulations were used to design a pilot experiment with liver spheroids as the 3DCA and glucose as the target molecule. Experimental results agree with the proposed theory and derived properties. [ABSTRACT FROM AUTHOR]

C(sp3)−H functionalization methods have been widely employed in many organic transformations such as cyclization reactions, heterocycle synthesis, cross‐coupling protocols, and photochemical transformations. Among these transformations, cyclization reaction through C(sp3)−H functionalization offers a direct route to convert simple linear substrates to complex products. There are three common modes of utilizing C(sp3)−H bonds in cyclization reactions including single, double, and dual C(sp3)−H functionalization. As the most challenging mode, dual C(sp3)−H functionalization refers to converting two separate C(sp3)−H bonds in one molecule into desired C−Z bonds which can be employed in cyclization reactions. Cyclization reaction via dual functionalization of C(sp3)−H bonds can be classified based on the C−H reactivities. Therefore, these reactions can be categorized into three classes based on the types of C(sp3)−H bonds including activated‐activated, activated‐unactivated, and unactivated‐unactivated C(sp3)−H bonds. Most published reports for cyclization reactions through dual C(sp3)−H functionalization involve activated‐activated C(sp3)−H bonds. However, the number of reported papers on the other two classes has been growing. This review focuses on the dual C(sp3)−H functionalization protocols used for cyclization reactions and categorizes the published papers based on the types of C(sp3)−H bonds. [ABSTRACT FROM AUTHOR]

Ferritin (Ft) is a protein with a peculiar three-dimensional architecture. It is characterized by a hollow cage structure and is responsible for iron storage and detoxification in almost all living organisms. It has attracted the interest of the scientific community thanks to its appealing features, such as its nano size, thermal and pH stability, ease of functionalization, and low cost for large-scale production. Together with high storage capacity, these properties qualify Ft as a promising nanocarrier for the development of delivery systems for numerous types of biologically active molecules. In this paper, we introduce the basic structural and functional aspects of the protein, and summarize the methods employed to load bioactive molecules within the ferritin nanocage. [ABSTRACT FROM AUTHOR]

The multiplicative first Zagreb index is the product of the square of the degree of vertices in a graph G. The multiplicative reformulated first Zagreb index is defined as Π1, e (G) = Πx12x2∈E(G) (dG(x1) +dG(x1) - 2)²,where E(G) is the edge set of a graph G and dG(x1) is the degree of a vertex x1 in a graph G. In this paper, we characterize the minimum and maximum trees and unicyclic graphs with respect to matching and perfect matching using this graph invariant Π1,e(G) among the collection of all n-vertex graphs. [ABSTRACT FROM AUTHOR]

The article discusses a group contribution (GC) method used to calculate the partition coefficients of organic molecules. The GC method assumes that certain aspects of chemical groups are consistent across different molecules. The authors of the article criticize previous publications by Naef and Acree for overlooking relevant research and not providing a rebuttal. They also compare Naef and Acree's results on the octanol-water partition coefficient to previous studies and highlight the limitations of their method. The authors suggest that Naef and Acree's claims of unmatched versatility are not supported by the literature. [Extracted from the article]

A novel RGB color patterning method for the fabrication of AMOLEDs was demonstrated on a lab scale in this work. Jouleheating Induced Color Patterning (JICP) is a high resolution patterning process where sublimation of small organic molecules is induced by applying electric pulse to a pre-patterned conductive layer on a donor glass. It was found that the JICP process has a potential for high resolution patterning of >700 ppi and for patterning large-sized panels such as Gen. 8 glass substrate. [ABSTRACT FROM AUTHOR]

In remote sensing applications, such as differential optical absorption spectroscopy (DOAS), atmospheric scattering processes need to be considered. After inelastic scattering on N2 and O2 molecules, the scattered photons occur as additional intensity at a different wavelength, effectively leading to filling-in of both solar Fraunhofer lines and absorptions of atmospheric constituents. Measured spectra in passive DOAS applications are typically corrected for rotational Raman scattering (RRS), also called Ring effect, which represents the main contribution to inelastic scattering. In contrast to that, vibrational Raman scattering (VRS) of N2 and O2 has often been thought to be negligible, but also contributes. Consequences of VRS are red-shifted Fraunhofer structures in scattered light spectra and filling-in of Fraunhofer lines, additional to RRS. We describe how to calculate VRS correction spectra in analogy to the Ring spectrum. We discuss further the impact of VRS cross-sections for O2 and N2 on passive DOAS measurements. The relevance of VRS is shown for the first time in spectral evaluations of Multi-Axis DOAS data. This measurement data yields in agreement with calculated scattering cross-sections, that the observed VRS cross-section amounts to 2.2±0.4% of the cross-section of RRS under tropospheric conditions. It is concluded, that this phenomenon has to be included in the spectral evaluation of weak absorbers as it reduces the measurement error significantly and can cause apparent differential optical depth of up to 2.5 × 10-4. Its influence on the spectral retrieval of IO, Glyoxal, water vapour and NO2 in the blue wavelength range is evaluated. For measurements with a large Ring signal a significant and systematic bias of NO2 dSCDs up to (-3.8±0.4) × 1014 molec cm-2 at low elevation angles is observed if this effect is not considered. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to a novel fabricated resonator structure which consists of some single mechanical resonators as a mass sensor. Design/methodology/approach: The structure is proposed to detect the target molecules and cells in a droplet. Also, at this design the mechanical coupling springs of the proposed structure are designed in such a way that it resonates in shear resonance mode which minimizes the damping effect. Findings: This proposed design can be fabricated in different sizes due to the requirements of an application. Originality/value: The proposed design is fabricated in mesoscale and its mass sensitivity is evaluated and reported in this paper. [ABSTRACT FROM AUTHOR]

In liquid water, there is a natural tendency to form aggregates that consist of water molecules linked by hydrogen bonds. Such spontaneously formed aggregates are surrounded by a "sea" of disordered water molecules, with both forms remaining in equilibrium. The process of creating water aggregates also takes place in the solvation water of proteins, but in this case, the interactions of water molecules with the protein surface shift the equilibrium of the process. In this paper, we analyze the structural properties of the solvation water in antifreeze proteins (AFPs). The results of molecular dynamics analysis with the use of various parameters related to the structure of solvation water on the protein surface are presented. We found that in the vicinity of the active region responsible for the binding of AFPs to ice, the equilibrium is clearly shifted toward the formation of "ice-like aggregates," and the solvation water has a more ordered ice-like structure. We have demonstrated that a reduction in the tendency to create "ice-like aggregates" results in a significant reduction in the antifreeze activity of the protein. We conclude that shifting the equilibrium in favor of the formation of "ice-like aggregates" in the solvation water in the active region is a prerequisite for the biological functionality of AFPs, at least for AFPs having a well-defined ice binding area. In addition, our results fully confirm the validity of the "anchored clathrate water" concept, formulated by Garnham et al. [Proc. Natl. Acad. Sci. U. S. A. 108, 7363 (2011)]. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive study of the theory of entangled two-photon emission/absorption (E2P-EA) between a many-level cascade donor and a many-level acceptor (which could be quantum dots or molecules) using second-order perturbation theory and where the donor–acceptor pair is in a homogeneous but dispersive medium. To understand the mechanism of E2P-EA, we analyze how dipole orientation, radiative lifetime, energy detuning between intermediate states, separation distance, and entanglement time impact the E2P-EA rate. Our study shows that there are quantum interference effects in the E2P-EA rate expression that lead to oscillations in the rate as a function of entanglement time. Furthermore, we find that the E2P-EA rate for a representative system consisting of two quantum dots can be comparable to one-photon emission/absorption (OP-EA) when donor and acceptor are within a few nm. However, the E2P-EA rate falls off much more quickly with separation distance than does OP-EA. [ABSTRACT FROM AUTHOR]

This paper focuses on a new superposition between a single lump wave, breather waves and line solitons of the (2 + 1) -dimensional generalized Korteweg–de Vries (gKdV) equation. After deriving the N-soliton solutions, a new constraint, the long-wave limit and mode resonance method are used to construct a new hybrid solution. Further, a new velocity resonance condition is proposed to obtain a velocity resonance solution consisting of a single lump wave, a line soliton and breather waves, which remains relatively stationary and form a new bound state. It is worth pointing out that in most of the previous literature, lump wave and other waves will separate after they collide, but this paper derives a different result. [ABSTRACT FROM AUTHOR]

Our new density functional theory calculations by Gaussian reproduce the bond lengths and Raman spectra of a number of model tetrahedral Si and P compounds [the ten compounds in the SiHxD4−x and SiFxCl4−x (x = 0–4) series, and the tetramer P4O10]. The number of symmetric A1 peaks is determined by group theory, and the center of mass is especially important for the assignment of the three A1 peaks for P4O10 to the two P–O stretches and the O–P–O bend. Additional Gaussian calculations on isolated C3v PO4 tetrahedra, using the P–O bond lengths and O–P–O bond angles from the P4O10 optimization, also reproduce the three peak P4O10 Raman spectra and provide an important guide to the assignment of the two low energy peaks at ∼500 and ∼700 cm−1 to the P–BO (BO = P–O–P) stretch and BO–P–BO bend, respectively, in contrast to all earlier assignments. In the SiFxCl4−x series, there is a regular increase in the Si–F A1 frequency and a decrease in the Si–Cl A1 frequency across the series. Similar trends are seen in the SiClx(CH3)4−x series, and these trends are due to changes in the electron densities in the tetrahedron when an electronegative F or Cl is replaced by a less electronegative Cl or CH3, as measured by previous Si 2p, F 1s, Cl 2p, and C 1s x-ray photoelectron spectroscopy. These considerations serve as a guide for the interpretation of the Raman spectra of silicate glasses in Paper II [Bancroft et al., AIP Adv. 13, 125216 (2023)]. [ABSTRACT FROM AUTHOR]

This document is a list of contributions to a special issue titled "Molecules from Side Reactions II" in the journal Molbank. The special issue focuses on the synthesis and characterization of molecules obtained from unexpected and unpredictable synthetic routes. The research on side products is important as they can lead to new syntheses and provide insights into reaction mechanisms. The special issue includes 17 papers, with Italy contributing the most research. The topics covered in the special issue include the synthesis of heterocycles, carbohydrates, modified nucleosides, mechanisms of reactions, green chemistry, and chemistry of natural substances. The document also acknowledges the rigorous review process and the support of the editor-in-chief and editorial office staff. [Extracted from the article]

We demonstrate that the degradation in Alq3-based OLEDs is caused by the photophysical degradation processes of α-NPD and Alq3 molecules in the vicinity of the α-NPD/Alq3 interface. Two degradation pathways with different time constants take place during a decrease in electroluminescence under constant current operation. From time resolved photoluminescence measurements, we identify the first stage of the degradation is due to the decomposition of α-NPD molecules via the singlet excited states formed by recombining charge carriers. The second stage of the degradation is attributed to the formation of a luminescent quencher originated from the reaction of excited state of Alq3. [ABSTRACT FROM AUTHOR]

This paper evaluates the agreement between stratospheric NO2 retrievals from infrared limb sounders (MIPAS and HIRDLS) and solar UV/VIS backscatter sensors (OMI, SCIAMACHY limb and nadir) over the 2005-2007 period and across the sea- sons. The observational agreement is contrasted with the representation of NO2 profiles in 3-D chemical transport models such as the Whole Atmosphere Community Climate Model (SD-WACCM) and TM4. A conclusion central to this work is that the definition of a reference for stratospheric NO2 columns formed by consistent agreement among SCIAMACHY, MIPAS and HIRDLS limb records (all of which agree to within 0.25 × 1015 moleculescm-2 or better than 10%) allows us to draw attention to relative errors in other datasets, e.g.: (1) the WACCM model overestimates NO2 densities in the extratropical lower stratosphere, particularly over northern latitudes by up to 35% relative to limb observations, and (2) there are remarkable discrepancies between stratospheric NO2 column estimates from limb and nadir techniques, with a characteristic seasonal and latitude dependent pattern. We find that SCIAMACHY nadir and OMI stratospheric columns show overall biases of -0.6 × 1015 moleculescm-2 (-20 %) and +0.6 × 1015 moleculescm-2 (+20 %) relative to limb observations. It is highlighted that biases in nadir stratospheric columns are not expected to affect tropospheric retrievals significantly, and that they can be attributed to errors in the total slant column density, either related to algorithmic or instrumental effects. In order to obtain accurate and long time series of stratospheric NO2, a critical evaluation of the currently used Differential Optical Absorption Spectroscopy (DOAS) approaches to nadir retrievals becomes essential, as well as their agreement to limb and ground-based observations, particularly now that limb techniques are giving way to nadir observations as the next generation of climate and air quality monitoring instruments pushes forth. [ABSTRACT FROM AUTHOR]