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Chloropropanols such as 3-monochloropropane-1,2-diol (3-MCPD) and 1,3-dichloro-2-propanol (1,3-DCP) have drawn increasing attention due to their release from food contact paper and their potential carcinogenic effects. In this study, the effects were investigated of water extraction conditions on release of chloropropanols from food contact paper, and the extraction efficiencies of chloropropanols by water extract and migration method were compared. Cold water was found to be more severe than hot water for extraction of chloropropanols, with the highest water extraction value obtained at 23°C. Two hours of extraction was sufficient as the chloropropanols can be fully extracted from food contact paper within a short period of time. Increase of temperature in the range of 10°C–60°C had little impact on release of chloropropanols, however, the extraction of chloropropanols decreased when high temperatures (80°C or above) were applied due to volatilisation losses. Hence, attention should be paid when choosing extract conditions representing the worst-case scenario. The water extraction value using EN 645 method gives higher results compared to migration test described in GB 31604.1 and GB 5009.156, suggesting that the water extract method was probably more severe. For migration test, aqueous-based simulants were found to be more conservative than oil-based simulants, suggesting the conventional experiment conditions applicable for compliance test of chloropropanols migration can be simplified and optimised. [ABSTRACT FROM AUTHOR]

Thermal paper poses a significant challenge to latent print development as it tends to change color when traditional fingerprint development formulations are applied to it. In this study, the optimal components of ninhydrin, 1,2-indanedione, 1,8-diazafluoren-9-one ( DFO), and 5-methylthioninhydrin (5- MTN) for yielding clear fingerprints on thermal paper were determined by systematically adjusting the relative amounts of the reagents, polar solvents, and the nonpolar diluent petroleum ether, followed by validation on text-printed thermal paper. Specifically, 3.0% ethyl acetate as the polar solvent in petroleum ether was found to be the optimal combination; the optimal dilution ratios of ninhydrin, DFO, and 5- MTN original solutions with petroleum ether were 1 to 2, 11, and 7, respectively. The optimal concentration of 1,2-indanedione in petroleum ether was 0.125 g/L, with a string of 0.5% ethyl acetate in petroleum ether. [ABSTRACT FROM AUTHOR]

The presented paper investigates the creation of chitosan-based composites on the surface of chemically modified poly-D-lactic acid (PDLA). PDLA was dissolved in chloroform and cast into a glass dish until the complete evaporation of the solvent. The surface of the created PDLA films was modified with 1,6-hexanediamine and glutaraldehyde for the creation of free aldehyde side groups. Composite layers of chitosan (CH) were deposited on the surface of the modified films. The mechanical properties of the composite films were investigated using a dynamometer. The surface morphology of the created composite films was studied with Scanning electron microscopy (SEM). Sessile drop method was used to determine the surface free energy of the created chitosan-based composite layers. [ABSTRACT FROM AUTHOR]

The development of 1,8-naphthalimide derivatives as cell probes, DNA targeting agents, and anti-tumor drugs is one of the research hotspots in the field of medicine. Naphthalimide compounds are a kind of DNA embedder, which can change the topological structure of DNA by embedding in the middle of DNA base pairs, and then affect the recognition and action of topoisomerase on DNA. Aminofide and mitonafide are the first 2 drugs to undergo clinical trials. They have good DNA insertion ability, can embed DNA double-stranded structure, and induce topoisomerase II to cut part of pBR322DNA, but not yet entered the market due to their toxicity. In this paper, the design and structure-activity relationship of mononaphthalimide and bisaphthalimide compounds were studied, and the relationship between the structure of naphthalimide and anti-tumor activity was analyzed and discussed. It was found that a variety of structural modifications were significant in improving anti-tumor activity and reducing toxicity. [ABSTRACT FROM AUTHOR]

In this paper, we define a new type of open sets called co-Lindelöf open set (coL-open). Moreover, we obtain several results about co-Lindelöf open sets and study the relation among open set, coc-open set and coL-open. Furthermore, we define separation axioms via coLopen and prove some related results. [ABSTRACT FROM AUTHOR]

A thin film of poly-([IrCl(cod)(NHC-onbe)] n-(propyl-onbe) m) (onbe=oxanorbornene) coated on filter paper reacts quantitatively with CO to yield 1,5-cyclooctadiene, the unpleasant smell of which can be detected by the human olfactory system with very high sensitivity. Odorless, but toxic CO is thus 'translated' into the distinct smell of 1,5-cyclooctadiene. Based on malodorogenic sensing it is possible to smell the presence of CO. [ABSTRACT FROM AUTHOR]

Point-of-care testing (POCT) technology allows scientists to monitor and diagnose diseases at the patient site, much faster than classical lab-based methods. Herein, a rapid, simple, and sensitive 3D printed microfluidic device integrated with smartphone-based on-chip detection is described for POCT quantification of urinary uric acid. The device includes two circular inputs each connected to a microliter-scale chamber, separated by an integrated porous membrane, located between the sample and reagent chambers. The microfluidic device was fabricated from a transparent photopolymer using a 3D printer, in a single run. The concentration of uric acid was determined based on a chromogenic reaction in which ferrous ion, produced via the reduction of ferric ion by the analyte, complexed with 1,10-phenanthroline, and the color was recorded by a smartphone. Response surface methodology including a central composed design was utilized to evaluate the experimental parameters and subsequent introduction of a multivariate model to describe the experimental conditions. Under the optimum conditions, the calibration curve was linear over the concentration range of 30–600 mg L−1. The limit of detection was determined to be 10.5 mg L−1. The microfluidic device was successfully utilized for the recovery and quantification of uric acid in the urine, with recoveries ranging from 91.7 to 99.7%. A microfluidic device was 3D printed for the determination of uric acid levels in urine. The device was coupled with a smartphone-based colorimetric method. Response surface methodology including central composed design was used to optimize experimental variables. This device shows promise for the evaluation of renal and kidney function. [ABSTRACT FROM AUTHOR]

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This paper investigates the optimal tracking performance based on the codec, colored noise, and bandwidth constraints in the network time‐delay systems. Choosing the optimal two‐degree‐of‐freedom compensator and the dominant expression of the system optimal tracking performance is obtained after Youla parameterization by using the coprime factorizations method and spectral decomposition technology. The result shows that the tracking performance of the system is determined by the nonminimum phase zero and unstable pole of the controlled plant. Moreover, codec, colored noise, and bandwidth constraints can also significantly impact the performance. Finally, two simulation examples prove the accuracy of the theory. [ABSTRACT FROM AUTHOR]

Supramolecular gels with metal ion-responsiveness are an important kind of smart materials due to their potential application in environmental monitoring. In this study, a novel l -glutamine-contained 1,8-naphthalimide derivative (NDG) has been designed and synthesized as an organogelator. NDG could self-assemble into stable supramolecular organogels in different kind of solvents, and the gelation process showed bright blue aggregation-induced emission (AIE). The self-assembly behavior, morphology and structure of NDG gels were thoroughly studied by various techniques. Interestingly, the obtained NDG organogel exhibited a fluorescence "turn-off" response for Fe3+ and formed a stable metallogel NDG -Fe3+. The detection limit (LOD) of NDG in diluted solution and gel states for Fe3+ was calculated to be 30.8 nM and 11.5 nM, respectively, indicating high sensitivity. In addition, the blue fluorescence emission of the gel system was restored in the presence of ascorbic acid and then quenched again with oxygen, which showed reversible fluorescence sensing effect and employed as a logic gate at the molecular level. Furthermore, xerogel-based film of NDG emitted strong blue emission and could be utilized as paper-based chemosensor to detect Fe3+. And also, the NDG gel had potential application in fluorescence display material. [Display omitted] • A l -glutamine-contained 1,8-naphthalimide gelator was synthesized with AIE effect. • The organogel exhibited a fluorescence response for Fe3+ by gel-gel transition. • The gel system was potentially constructed as a molecular logic gate. • Paper-based gel film was used in Fe3+ recognition and as display material. [ABSTRACT FROM AUTHOR]

In this paper, a cyclotetrasiloxane modified with epoxy resin was synthesized via hydrosilylation with 1, 3, 5, 7-tetramethylcyclotetrasiloxane (D4H) and 4-vinyl-1-cyclohexane 1, 2-epoxide (VCHO). The structure of tetramethylcyclotetrasiloxane modified with cyclohexane epoxide (D4H–VCHO) was characterized by Fourier transform infrared (FT-IR), 1H nuclear magnetic resonance (1H-NMR) and gel permeation chromatography (GPC). The effects of feeding methods, feeding ratios, catalyst dosages, reaction temperature and reaction time on the products were investigated. After 4-h reaction with 8 ppm catalyst at 90 °C, D4H–VCHO was obtained with an epoxy value of 0.521 and a refractive index of 1.4920. Then, with 4-methylhexahydrophthalic anhydride as a curing agent and tetrabutylammonium bromide as a catalyst, the obtained D4H–VCHO was cured at 90 °C for 1 h and then 120 °C for another hour. The cured products showed high light transmittance, strong thermal stability, suitable hardness and low water absorption. The glass transition temperature of cured materials was 151.6 °C, indicating the improvement of flexibility. In addition, the introduction of epoxy groups greatly enhanced the adhesion of silicone resins to substrates. The results demonstrated that the epoxy-modified silicone materials could be applied as LED packaging materials. [ABSTRACT FROM AUTHOR]

A vertex subset S of a graph G = (V , E) is a [ 1 , 2 ] -dominating set if each vertex of V ∖ S is adjacent to either one or two vertices in S. The minimum cardinality of a [ 1 , 2 ] -dominating set of G , denoted by γ [ 1 , 2 ] (G) , is called the [ 1 , 2 ] -domination number of G. In this paper, the [ 1 , 2 ] -domination and the [ 1 , 2 ] -total domination numbers of the generalized Petersen graphs P (n , 2) are determined. [ABSTRACT FROM AUTHOR]

Several notions on soft topology are studied and their basic properties are investigated by using the concept of soft pre open sets and soft pre closure operator which are derived from the basics of soft set theory established by Molodtsov [1]. In this paper we introduce some soft separation axioms called Soft pre R0 and soft pre R1 in soft topological spaces which are defined over an initial universe with a fixed set of parameters. Many characterizations and properties of these spaces have been demonstrated. Necessary and sufficient conditions for a soft topological space to be a soft pre Ri space for i = 0, 1 were also presented. Furthermore, the concept of functions with soft pre closed graph and soft pre cluster set are defined. Many results on these two concepts are proved. Also, it is proved that a function has a soft pre closed graph if and only if its soft pre cluster set is degenerate. ©2022 All rights reserved. [ABSTRACT FROM AUTHOR]

In this paper, diamine monomers with ether bonds in the main chain are selected for molecular structure design, and four polyamide-imide (PAI) materials are prepared by the acyl chloride method. A diamine monomer containing an ether group can reduce the friction coefficient and improve the wear performance of PAI material. The wear mechanism of PAI material can also change due to ether linkages. PAI synthesized using m -phenylenediamine without an ether bond has the highest friction coefficient and abrasion loss, and the wear mechanism is mainly adhesive wear. With the increase of the number of ether bonds in the diamine monomer structure, the friction coefficient of the material decreases from 0.5445 to 0.4216 (22.57 %). The abrasion loss of the PAI material synthesized using 4,4′-diaminodiphenyl ether is the smallest, which is 84.4 % lower than m -phenylenediamine. The wear mechanism is abrasive wear and slight adhesion wear. With the increase of the number of ether bonds, the heat r esistance of PAI decreases slightly, while the hydrophobic property increases and the water absorption decreases. To summarise, PAI material synthesized using 4,4′-diaminodiphenyl ether has a low friction coefficient, the best wear resistance, the highest tensile strength and elongation at break, and the best comprehensive properties of the materials reported here. A diamine monomer containing an ether group can reduce the friction coefficient and improve the wear performance of PAI material, and the wear mechanism of the PAI material can also change due to ether linkages. [ABSTRACT FROM AUTHOR]

Hydrazine (N 2 H 4), as a highly reducing agent and reactive base, is extensively utilized in chemical, pharmaceutical and agriculture fields. However, the high toxicity of N 2 H 4 poses significant risks to human health and can lead to severe ecological contamination. Consequently, it is of significant to develop a tool for the detection of N 2 H 4 in the environment fields and in vivo. Herein, three 1,8-naphthalimide-triphenylamine-based red-emitting fluorescence probes (TSY-1 , TSY-2 and TSY-3) have been developed for the detection of N 2 H 4 in actual water sample and in vivo by coupling of 1,8-naphthalimide derivatives with the electron-withdrawing groups (1,3-indandione, malononitrile, and 2-benzothiazolethonitrile) through a N 2 H 4 responsive C C bond. Significant fluorescence quenching of three probes was observed on account of the responses toward N 2 H 4. The detection limits of TSY-1 , TSY-2 and TSY-3 for N 2 H 4 were calculated to be 0.2 μM, 0.4 μM and 54 μM, respectively. Utilizations of probe-based test paper strips to qualitatively detect N 2 H 4 in actual water sample by "naked-eye" colorimetry were demonstrated. Additionally, quantitative determination of N 2 H 4 in actual water samples was successfully achieved by the smartphone-based standard curves. Additionally, the applications of TSY-1 , TSY-2 and TSY-3 in fluorescence imaging N 2 H 4 in vivo are also demonstrated. [Display omitted] • Three red emitting probes are developed for high selective and sensitive detection of N 2 H 2 in water of wide pH range. • Probe-based test paper strips for "naked-eye" detection of N 2 H 4 level in real-world water samples are obtained. • Determination of N 2 H 4 in real-world water samples is achieved by the smartphone-based approach. • Applications of the three probes in fluorescence imaging of N 2 H 4 in vivo are demonstrated. [ABSTRACT FROM AUTHOR]

Environmental concerns from global warming and climate change demand carbon dioxide separation from post-combustion gases. Important parameters are involved in choosing the suitable solvent for carbon dioxide separation, including the reaction rate of carbon dioxide and the solvent. In this paper, the kinetics of carbon dioxide (CO2) absorption in aqueous solutions of Monoethanolamine (MEA) + 1,3-Diaminopropane (DAP), a diamine containing two primary amino group, was developed. The measurements were performed in a stirred cell with a horizontal gas-liquid interface in the temperature range of 313.15–333.15 K and aqueous solutions of 10 wt% MEA + 5 wt% DAP and 12.5 wt% MEA + 2.5 wt% DAP. Experiments were conducted in an isothermal batch reactor with a horizontal gas-liquid interface under pseudo-first-order conditions, enabling the determination of the overall kinetic rate constant from the pressure drop method. Second-order reaction rate constants of CO2 absorption in amine solutions were estimated using the calculated initial absorption rate. It was found that the rate constants in MEA+ DAP solutions were greater than in MEA solutions which means that DAP increases the reaction rate. [ABSTRACT FROM AUTHOR]

It is a well-known fact that by changing the 1,3-dipolar cycloaddition (1,3- DC) reaction mechanism from concerted to stepwise, the stereospecificity is lost; since in synthesizing the required heterocyclic molecules that reaction is a requisite, it is important to study the concertedness of that reaction. Several papers on this subject have already stated that the existence of electron withdrawing groups ( EWG) or electron donor groups ( EDG) on dipole or dipolarophile leads to a high-energy differentiation between the dipole HOMO and dipolarophile LUMO (or vice versa) as well as the emergence of an intermediate in the reaction pathway. This paper seeks answering the question of when an EWG on dipole and an EDG on dipolarophile could be a factor in making the reaction mechanism stepwise, and does repositioning of functional groups in replacing dipole and dipolarophile switches the reaction mechanism from stepwise into concerted or vice versa? [ABSTRACT FROM AUTHOR]

At the RoboCup, a robotics soccer tournament, the Small Size League (SSL) is one of its leagues. The thought of a mechanism in this league that could perform unpredictable kicks and passes inspired study into both the physical mechanism required to do it and the algorithms needed to make the most of it.By introducing new ideas and utilizing a Deep Neural Network, this work contributes by improving a prior algorithm that aims to carry out a real-time inversion of the non-linear ordinary differential equation (ODE) that models the ball’s path in order to determine the parameters to hit a target with a curved kick mechanism (DNN). New techniques are also presented. The two suggested DNN achieved accuracy levels of more than 92% in the outcomes of simulation runs in MATLAB. [ABSTRACT FROM AUTHOR]

In this paper, we first examine the relationships between a double sequence and its arithmetic means in different senses (i. e. (C, 1, 0), (C, 0,1) and (C, 1,1) means) in terms of slow oscillation in certain senses and investigate some properties of oscillatory behaviors of the difference sequence between the double sequence and its arithmetic means in different senses. Next, we give an alternative proof of the generalized Littlewood Tauberian theorem for Cesaro summability method as an application of the results obtained in the first part. [ABSTRACT FROM AUTHOR]

1,3-Dioleoyl-2-palmitoylglycerol (OPO) is a kind of structured triglyceride which could instead human milk fat (HMF) for the fat of infant formula, this kind of structured triglyceride is good at absorbing easily. The aim of this paper was to produce OPO though three different processing technologies. The raw material for the first method (Method 1) and second method (Method 2) was palm oil, and their catalyst is Novozym 435 and Lipozyme TL IM. The difference was the Method 1, which obtained tripalmitin (PPP) by acidolysis palm oil and palmitic acid (PA), then obtained OPO by acidolysis PPP and oleic acid (OA), Method 2 was acidolysis palm oil and mixed fatty acids directly without crystallization. The third method (Method 3) produced palm stearin (PS) enriched in PA by catalyzing palm stearin with sodium methoxide firstly, and then palm stearin enriched in PA and mixed vegetable oils catalyzed by Lipozyme TL IM. The content of OPO and sn-2 position PA of three methods was higher than 40.34% and 39.34%. The relative content of PA located at the sn-2 position and OA located at the sn-1, 3 position was higher than 59.97% and 66.01%. Among the three methods, the methods related to enzyme appeared safer, and Method 3 was easier for manufacturing OPO and saved time, so it should be more suitable for industrial production. [ABSTRACT FROM AUTHOR]

Staphylococcus epidermidis, a harmless human skin colonizer, is a significant nosocomial pathogen in predisposed hosts because of its capability to form a biofilm on indwelling medical devices. In a recent paper, the purification and identification of the pentadecanal produced by the Antarctic bacterium Pseudoalteromonas haloplanktis TAC125, able to impair S. epidermidis biofilm formation, were reported. Here the authors report on the chemical synthesis of pentadecanal derivatives, their anti-biofilm activity on S. epidermidis, and their action in combination with antibiotics. The results clearly indicate that the pentadecanal derivatives were able to prevent, to a different extent, biofilm formation and that pentadecanoic acid positively modulated the antimicrobial activity of the vancomycin. The cytotoxicity of these new anti-biofilm molecules was tested on two different immortalized eukaryotic cell lines in view of their potential applications. [ABSTRACT FROM AUTHOR]

Two fluorescent sensors based on 1,10-phenanthroline, 2-(2-fluorophenyl)-1 H -imidazo[4,5- f ][1,10]phenanthroline (L1) and 2-(2-iodophenyl) -1 H -imidazo[4,5- f ][1,10]phenanthroline (L2) were designed and synthesized for sensitive and selective detection of Zn2+ in methanol, test paper and actual water samples. The results of strip test and real water sample test showed that sensors 1 and 2 have potential application in environmental metal ion recognition and detection. [Display omitted] • Two fluorescent sensors were designed and synthesized for sensitive and selective detection of Zn2+ in methanol, test paper and actual water samples. Synthesis of two fluorescent sensors based on 1,10-phenanthroline, 2-(2-fluorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline (L1) and 2-(2-iodophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline (L2). Their recognition of Fe3+, Co2+, Ni2+, Zn2+, Cd2+, Cu2+, Mn2+, Eu3+, K+, Ca2+, Na+, Mg2+, Cr3+, Ag+, Hg2+, and Fe2+ was investigated using UV–vis absorption and fluorescence emission spectroscopy, and the results showed that L1 and L2 could be detected by significant fluorescence enhancement and naked eye color changes to achieve the identification of Zn2+. The high sensitivity of L1 and L2, with detection limits as low as 0.092 uM and 0.12 uM, respectively, indicates that the sensors have the ability to detect trace amounts of Zn2+. The binding stoichiometry ratio of L1-Zn2+ and L2-Zn2+ was determined by the Job's plot method to be 3:1. In addition, the test strip test and the actual water sample test showed their potential application in environmental ion identification. [ABSTRACT FROM AUTHOR]

1,4_Bis(methoxymethyl) benzene is an important fine chemical raw material and synthesis intermediate, mainly used for the synthesis of polymer resins. This paper classifies the synthetic methods of 1.4-bis (methoxy methyl) benzene and summarizes the advantages and disadvantages of these methods. The 1.4-bis(chloromethyl) benzene route has the advantages of easy availability of raw materials, simple operation and high yield, but halogens will be converted into halide salts, which results in poor atomic economy and high post-processing costs. In the 1benzenedimethanol route, when dimethyl sulfate is used as the etherificating reagent, the by-products are mainly sulfuric acid and methyl sulfate, which are strongly irritating and corrosive, requiring suitable equipment; while dimethyl carbonate is used as the etherificating reagent, the catalyst is easily available and the by-products are mainly methanol and CO2, but the reaction conditions are harsh, requiring high temperature and high pressure. Dimethyl terephthalate is directly hydrogenated to prepare 1bis(me th oxy methyl) benzene route has the simple reaction steps, but it requires expensive catalysts, high temperature and high pressure. On the whole, dimethyl carbonate used as etherificating reagent reacts with 1,4-enzenedimethanol to transesterify and decarboxylate to produce 1,4-bis (methoxymethyl) benzene, doesnJ t introduce halogens, with low contamination degree. And the release of CO2 is conducive to promoting the positive reaction, bringing high product yield. This route has the prospect of realizing green industrialized production. [ABSTRACT FROM AUTHOR]

This paper mainly studied Pd-catalyzed regioselective chlorination of disubstituted 1,2,3-triazoles directed by the 1,2,3-triazole ring. A series of regioselective chlorinated products were synthesized in 47-86% yields using Pd(OAc)2 as a catalyst and CuCl2 as a chlorinated reagent. This method provides a new mean for the synthesis of 1,2,3-triazole halides which combines the formation of C-X bond with C-H activation. [ABSTRACT FROM AUTHOR]

This paper reports the synthesis and photophysical investigation of a novel 1,8-naphthalimide fluorophore containing 2-amino-1,3,4-thiadiazole fragment at C-4 position. Absorption and fluorescence characteristics of the dye as a function of pH were investigated in water/ethanol (1:1, v/v) solution. It was found that the synthesized 1,8-naphthalimide did not show significant changes in the emission properties in a wide pH range. Furthermore the ability of the synthesized compound to detect cations was evaluated by the changes in its fluorescence intensity in the presence of metal ions (Co2+, Cu2+, Fe3+, Ni2+, Pb2+, Cd2+, Zn2+ and Hg2+). Only Hg2+, among the tested metal ions, was efficiently detected due to the aggregation caused quenching process. The results obtained indicate the potential of the novel compound acting as a fluorescent "onoff" switch for selective determination of Hg2+ in a wide pH window. [ABSTRACT FROM AUTHOR]

In this paper we would like to discuss the efficient synthesis of pyrazin fused N-(3-Mercapto-5-Aryl-[1,2,4]triazol-4-yl)-amide (5a-m and 6a-r) from4-Amino-5-Aryl-4H-[1,2,4]triazole-3-thiols(4a-b) through N-acylaton under dry dioxane, R1COCl, reflux, 10 h by a sequential manner probably the steps are mentioned in Scheme-1, Table-1,2. The structures of the compounds were elucidated by spectral (IR,1HNMR, 13CNMR and MS) analysis. The reactions are easy to conduct, under mild conditions, and form amide substituted triazole derivatives with excellent yields. [ABSTRACT FROM AUTHOR]

Four 1-D chain coordination polymers containing bent 1,1′-binaphthyl ligands were synthesised with NiII, CuII and AgI. The use of (R)-4,4′-(2,2′-diethoxy-[1,1′-binaphthalene]-6,6′)dipyridine as a ligand yielded isostructural 1-D looping chains with NiII and CuII, whereas the use of AgI yielded both linear and helical 1-D chains. Changing the dipyridyl coordination groups to dicarboxylates in (S)-6,6′-dicarboxyl-2,2′-diethoxy-1,1′-binaphthalene yielded a 1-D looping chain with a CuII paddlewheel motif. The AgI 1-D chain features two crystallographically distinct 1-D chain morphologies with a triple helix and linear strips. The packing arrangement of the 1-D chains differs because of the intermolecular interactions present, with the steric bulk of the ethoxy substituent on the 1,1′-binaphthyl enabling the formation of large void spaces. Chiral supramolecular compounds containing 1,1′-binapthyl are increasingly explored for chiroptical techniques including fluorescence-based sensing. Careful design of these compounds can yield systems with accessible voids and complimentary intermolecular interactions that can be tailored as a function of the 1,1′-binapthyl's steric hinderance and hydrogen bonding ability. (Image credit: Carol Hua.) [ABSTRACT FROM AUTHOR]

Introduction: 24-Hydroxylase, encoded by the CYP24A1 gene, is a crucial enzyme involved in the catabolism of vitamin D. Loss-of-function mutations in CYP24A1 result in PTH-independent hypercalcaemia with high levels of 1,25(OH) 2D3. The variety of clinical manifestations depends on age, and underlying genetic predisposition mutations can lead to fatal infantile hypercalcaemia among neonates, whereas adult symptoms are usually mild. Aim of the study: We report a rare case of an adult with primary hyperparathyroidism and loss-of-function mutations in the CYP24A1 gene and a review of similar cases. Case presentation: We report the case of a 58-year-old woman diagnosed initially with primary hyperparathyroidism. Preoperatively, the suspected mass adjoining the upper pole of the left lobe of the thyroid gland was found via ultrasonography and confirmed by 99mTc scintigraphy and biopsy as the parathyroid gland. The patient underwent parathyroidectomy (a histopathology report revealed parathyroid adenoma), which led to normocalcaemia. After 10 months, vitamin D supplementation was introduced due to deficiency, and the calcium level remained within the reference range. Two years later, biochemical tests showed recurrence of hypercalcaemia with suppressed parathyroid hormone levels and elevated 1,25(OH)2D3 concentrations. Further investigation excluded the most common causes of PTH-independent hypercalcaemia, such as granulomatous disease, malignancy, and vitamin D intoxication. Subsequently, vitamin D metabolites were measured using LC-MS/MS, which revealed high levels of 25(OH)D3, low levels of 24,25(OH)2D3 and elevated 25(OH)2D3/24,25 (OH)2D3 ratios, suggesting a defect in vitamin D catabolism. Molecular analysis of the CYP24A1 gene using the NGS technique revealed two pathogenic variants: p.(Arg396Trp) and p.(Glu143del) (rs114368325 and rs777676129, respectively). Conclusions: The diagnostic process for hypercalcaemia becomes complicated when multiple causes of hypercalcaemia coexist. The measurement of vitamin D metabolites using LC-MS/MS may help to identify carriers of CYP24A1 mutations. Subsequent molecular testing may contribute to establishing the exact frequency of pathogenic variants of the CYP24A1 gene and introducing personalized treatment. [ABSTRACT FROM AUTHOR]

Non-equidistant non-homogenous grey model (abbreviated as NENGM (1,1, k) model) is a grey prediction model suitable for predicting time series with non-equal intervals. It is widely used in various fields of society due to its high prediction accuracy and strong adaptability. In order to further improve the prediction accuracy of the NENGM (1,1, k) model, the NENGM (1,1, k) model is optimized in terms of the cumulative order and background value of the NENGM (1,1, k) model, and a NENGM (1,1, k) model based on double optimization is established (abbreviated as FBNENGM (1,1, k) model), and the whale optimization algorithm is used to solve the best parameters of the model. In order to verify the feasibility and validity of the FBNENGM (1,1, k) model, the FBNENGM (1,1, k) model and other four prediction models are applied to three cases respectively, and three indexes commonly used to evaluate the performance of prediction models are used to distinguish. The results show that the prediction accuracy of the FBNENGM (1,1, k) model based on double optimization is better than other prediction models. [ABSTRACT FROM AUTHOR]

This article covers almost 130 Pt(ii) complexes with an inner coordination sphere of cis-PtP2Cl2. The P-donor ligands are organodiphosphines that create four-, five-, and six-membered metallocyclic rings. There are two types of four-membered rings: PCP and PNCP, and four types of five-membered rings: PC–CP, PC═CP, PNNP, and PCOP. There are wide varieties of the six-membered metallocyclic rings: PC3P (most common), PCNCP, PCSCP, PCSiCP, PNCNP, PCCOP, PCCNP, POPNP, POSiOP, P(CNC)2P, and P(CNC)(CCC)P. The P–Pt–P bite angles open with the size of the metallocyclic rings in the order (total mean values 72.4° [PXP] < 86.4° [PXXP] < 94.0° [PXXNP]). There are complexes that are examples of distortion and ligand isomerism. The structural data are analyzed and discussed. [ABSTRACT FROM AUTHOR]

1,3-thiazines were synthesised using Schiff base and 3-mercaptopropanoic acid and characterised. Using the Gaussian 09W program, the current investigation utilised the Hartree-Fock approximation (HF) to compute diverse molecular characteristics, comprising optimisation, hardness, EHOMO, ELUMO, and energy gap, for a collection of synthesised molecules. [ABSTRACT FROM AUTHOR]

The demand for the efficient utilization of biomass ‐ derived sugars has increased in the field of green and sustainable chemistry. In this paper, Sho Yamaguchi, Toshihide Baba et al. report a new route to the cascade synthesis of five ‐ membered lactones, which can be utilized not only as fine chemicals but also as chemical starting materials, using a biomass ‐ derived sugar (1,3 ‐ dihydroxyacetone, DHA) as a carbon nucleophile and various aldehydes. This achievement provides a new synthetic strategy to generate a wide range of valuable compounds from a single biomass ‐ derived sugar and electrophiles. More information can be found in the Full Paper by Sho Yamaguchi, Toshihide Baba et al. on page   1731 in Issue 11, 2016 (DOI: 10.1002/asia.201600307). [ABSTRACT FROM AUTHOR]

This paper develops some deeper consequences of an extended definition, proposed previously by the author, of pseudo-differential operators that are of type 1, 1 in Hörmander's sense. Thus, it contributes to the long-standing problem of creating a systematic theory of such operators. It is shown that type 1, 1-operators are defined and continuous on the full space of temperate distributions, if they fulfil Hörmander's twisted diagonal condition, or more generally if they belong to the self-adjoint subclass; and that they are always defined on the temperate smooth functions. As a main tool the paradifferential decomposition is derived for type 1, 1-operators, and to confirm a natural hypothesis the symmetric term is shown to cause the domain restrictions; whereas the other terms are shown to define nice type 1, 1-operators fulfilling the twisted diagonal condition. The decomposition is analysed in the type 1, 1-context by combining the Spectral Support Rule and the factorisation inequality, which gives pointwise estimates of pseudo-differential operators in terms of maximal functions. [ABSTRACT FROM AUTHOR]

This paper describes the synthesis of precursors with a benzo[b]furan skeleton for the intramolecular 1,3-dipolar cycloaddition of azomethine ylides prepared from N-substituted 3-allylaminobenzo[ b]furan-2-aldehydes and secondary amines derived from α-amino acid esters. Reactions were initiated by heating. The products consisted of four fused rings with three stereogenic centers. Their structure and stereochemistry were determined by NMR spectra and X-ray measurements. [ABSTRACT FROM AUTHOR]

The paper is mainly focused on the induced circular dichroism (ICD) based on central-to-axial chirality transfer for direct chiral recognition and ee value detection of 1,2-diaminocyclohexane (1,2-DACH) enantiomers. A novel achiral polymer sensor with potential axial chirality feature is designed and synthesized. This conjugated polymer incorporating biphenol moiety can bind chiral 1,2-DACH substrates via intramolecular hydrogen-bonding interactions, which could result in the detectable exciton-coupled circular dichroism (CD) spectrum due to the chirality transfer from an enantiopure building block to a dynamically racemic 1,1′-biphenyl-2,2′-diol moiety in the polymer chain backbone. The linear regression analysis of ICD sensing shows an excellent agreement between CD intensity and concentration of chiral 1,2-DACH, which indicates this biphenol-based achiral polymer can be used as a chiral sensor for direct recognition and ee value detection of 1,2-DACH enantiomers by using ICD spectra of achiral polymer sensor. [ABSTRACT FROM AUTHOR]