L 2-\overline{\partial}-Cohomology groups of some singular complex spaces

Let X be a pure n-dimensional (where n≥2) complex analytic subset in ? ^N with an isolated singularity at 0. In this paper we express the L ²-(0,q)- $\overline{\partial}$ -cohomology groups for all q with 1≤q≤n of a sufficiently small deleted neighborhood of the singular point in terms of resolution data. We also obtain identifications of the L ²-(0,q)- $\overline{\partial}$ -cohomology groups of the smooth points of X, in terms of resolution data, when X is either compact or an open relatively compact complex analytic subset of a reduced complex space with finitely many isolated singularities.     

Synthesis of 7a-substituted Hajos-Wiechert ketone analogues

A general and efficient route to 2-substituted 1,3-cyclopentadiones 3 has been developed. This operationally simple, two-step procedure is amenable to multigram scale preparations of these useful synthetic intermediates. These compounds are then transformed to previously unknown, higher analogues of the Hajos-Parrish-Eder-Sauer-Wiechert ketone (enone 1, R = Me) following an enantioselective Robinson annulation.     

Fiber Integrated Metal-Organic Frameworks as Functional Components in Smart Textiles

Owing to high modularity and synthetic tunability, metal–organic frameworks (MOFs) on textiles are poised to contribute to the development of state-of-the-art wearable systems with multifunctional performance. While these composite materials have demonstrated promising functions in sensing, filtration, detoxification, and biomedicine, their applicability in multifunctional systems is only beginning to materialize. This review highlights the multifunctionality and versatility of MOF-integrated textile systems. It summarizes the operational goals of MOF@textile composites, encompassing sensing, filtration, detoxification, drug delivery, UV protection, and photocatalysis. Building upon these recent advances, this review concludes with an outlook on emerging opportunities for the diverse applications of MOF@textile systems in the realm of smart wearables.     

A liquid chromatographic/tandem mass spectroscopic method for quantification of the cyclic peptide melanotan-II. Plasma and brain tissue concentrations following administration in mice

Melanotan-II (MT-II), a synthetic analogue of the natural melanocortin peptide, alpha-melanocyte-stimulating hormone (alpha-MSH), is well known for the anorexic effects it elicits in rodents. These effects are, at least partly, associated with agonistic action on the centrally located melanocortin receptors, MC3R and MC4R. Whether MT-II exerts this effect via brain penetration still remains unclear. In order to address this question we administered MT-II in rodents at efficacious doses and then employed a sensitive methodology for the determination of MT-II in plasma and brain samples. MT-II was extracted from mouse plasma and brain tissue by acetonitrile precipitation followed by liquid chromatography/tandem mass spectrometry (LC/MS/MS) analysis. The described assay improved significantly previously reported MT-II levels of quantification in rat plasma and brain. The lower limits of quantification (LLOQs) of 0.5 ng/mL and 2.5 ng/g were obtained in 50 microL plasma and 100 microL brain homogenate, respectively. The calibration curve was linear over the concentration range of 0.5-500 ng/mL for plasma and 2.5-250 ng/g for brain tissue. The method was successfully applied in measuring levels of MT-II in plasma and brain tissue following intraperitoneal (ip) administration of 1 mg/kg of peptide in mice. Following administration of MT-II, clearance from plasma was rapid. The sensitivity of the assay allowed the determination of low concentrations of MT-II (11.4 +/- 5.5 ng/g) in brain homogenate at 30 min after dosing. However, the brain concentrations when compared with the high plasma levels of MT-II at the same time point confirmed the low penetrability of the peptide in mouse brain.     

Fatty Acids and Their Metal Salts: A Review of Their Infrared Spectra in Light of Their Presence in Cultural Heritage

In a cultural heritage context, fatty acids are usually found as breakdown products of lipid-containing organic remains in archaeological findings, binders in aged oil paintings, and additives in modern art-related materials. They may further interact with the ionic environment transforming into metal soaps, a process that has been recognized as a threat in aged paintings but has received less attention in archaeological objects. The investigation of the above related categories of materials with infrared spectroscopy can provide an overall picture of the organic components’ identity and demonstrate their condition and prehistory. The capability of investigating and distinguishing fatty acids and their metal soaps through their rich infrared features, such as the acidic carbonyl, the carboxylate shifts, the variable splits of alkyl chain stretching, bending, twisting, wagging, and rocking vibrations, as well as the hydroxyl peak envelopes and acid dimer bands, allows for their direct detailed characterization. This paper reviews the infrared spectra of selected saturated fatty monoacids and diacids, and their corresponding sodium, calcium, and zinc salts and, supported by newly recorded data, highlights the significance of their spectroscopic features.     

New SPE loading material for affinity‐based separation of cyclodextrins from drug:CD complexes in order to overcome Beer's law deviations

Molecular inclusion of guest molecules within CDs is known to alter guest molecule spectrophotometric absorptivity, making their determination, based on spectrophotometric data, inaccurate. Therefore specific analytical methods capable of quantifying the drugs as free molecules must be developed and validated. SPE was selected to simplify sample and avoid more time‐consuming alternatives. A new solid phase was synthesized and characterized by infrared spectrometry, differential scanning calorimetry and elemental analysis. The competitive complexation of adamantane groups immobilized on the silica substrate facilitates drug:CD complex dissociation and elimination of CD from samples. The drug molecules, now free from CD, can be easily analysed by an already available HPLC method. This new SPE loading material was employed in the determination of ketoprofen in its CD complex as a representative example of the utility of this novel material. The calculated analytical errors were reduced from a maximum of 20.79% (without SPE) to a minimum of 3.99%.     

Diimidazo[4,5-b:4′,5′-e]pyridine: synthesis and nucleophilic aromatic substitution reaction

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Solvability of Semilinear Hemivariational Inequalities at Resonance Using Generalized Landesman–Lazer Conditions

In this paper we examine semilinear hemivariational inequalities at resonance at any eigenvalue of the negative Laplacian with Dirichlet boundary condition. Our approach is variational based on the Nonsmooth Critical Point Theory and it uses a generalized Landesman–Lazer condition. We prove two existence theorems using two different forms of the generalized Landesman–Lazer condition. In the last section we show that our Landesman-Lazer condition is more general than the ones existing in the literature.