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Background: The high morbidity, mortality and associated economic burden have entailed to identifying early biomarker of diabetic foot ulcers (DFU). Pro-inflammatory and anti-inflammatory molecules play a role in the chronic inflammation associated with diabetic foot ulcers (DFU). Aim: This study aims to find the association between ApoA1, IL-10, TNF-α and diabetic foot ulcers, and whether their levels can assess the severity of the disease. Method: Two groups, diabetic mellitus without foot ulcers and diabetes with foot ulcers were recruited for the study. Detailed clinical history was obtained and blood was collected to measure TNF-α , IL-10 and Apo A1. The association between variables was analysed using Pearson correlation test. ROC analysis was used to identify cut-off values of ApoA1, IL-10 and TNF-α in diabetes patients with foot ulcers. Results: The presence of pro-inflammatory parameter, TNF-α , was higher and anti-inflammatory biomarkers, HDL, ApoA1 and IL-10 were lower in patients of DFU than those without foot ulcers (p < 0.001). Increasing age, smoking, retinopathy, eGFR and inflammatory biomarkers like low levels of ApoA1 (p < 0.005) and IL-10 (p < 0.001) significantly contributed to the development of diabetic foot ulcers. ROC curve identified the cut-off for ApoA1 and IL-10 as 89.82mg/dL and 78.80pg/mL respectively. Conclusion: In the light of this study, ApoA1 has the potential to predict DFU. The finding proposes IL-10 (b = -0.37, p < 0.001) could be considered in stratifying DFU as per its severity.
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Smarter and minimization of devices are consistently substantial to shape the energy landscape. Significant amounts of endeavours have come forward as promising steps to surmount this formidable challenge. It is undeniable that material scientists were contemplating smarter material beyond purely inorganic or organic materials. To our delight, metal-organic frameworks (MOFs), an inorganic-organic hybrid scaffold with unprecedented tunability and smart functionalities, have recently started their journey as an alternative. In this review, we focus on such propitious potential of MOFs that was untapped over a long time. We cover the synthetic strategies and (or) post-synthetic modifications towards the formation of conductive MOFs and their underlying concepts of charge transfer with structural aspects. We addressed theoretical calculations with the experimental outcomes and spectroelectrochemistry, which will trigger vigorous impetus about intrinsic electronic behaviour of the conductive frameworks. Finally, we discussed electrocatalysts and energy storage devices stemming from conductive MOFs to meet energy demand in the near future.
Assuntos
Estruturas Metalorgânicas , Condutividade Elétrica , EletrônicaRESUMO
In this study, we report a synthetically simple donor-acceptor (D-A)-type organic solid-state emitter 1 that displays unique fluorescence switching under mechanical stimuli. Orange and yellow emissive crystals of 1 (1O, 1Y) exhibit an unusual "back and forth" fluorescence response to mechanical force. Gentle crushing (mild pressure) of the orange or yellow emissive crystal results in hypsochromic shift to cyan emissive fragments (λem = 498-501 nm) with a large wavelength shift Δλem = -71 to -96 nm, while further grinding results in bathochromic swing to green emissive powder λem = 540-550 nm, Δλem = +40 to 58 nm. Single-crystal X-ray diffraction study reveals that molecules are packed by weak interactions, such as C-H···π, C-H···N, and C-H···F, which facilitate intermolecular charge transfer in the crystal. With the aid of structural, spectroscopic, and morphological studies, we established the interplay between intermolecular and intramolecular charge-transfer interaction that is responsible for this elusive mechanochromic luminescence. Moreover, we have also demonstrated the application of this organic material for chlorine gas sensing in solid state.
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Postsynthetic modification is a promising tool for introducing multifunctional properties in metal-organic frameworks (MOFs). The effects of postsynthetic metal addition/exchange in a barium-based MOF have been well examined toward their magnetic and electrical properties. The rattling motion of the extraframework organic cation is responsible for the ferroelectric behavior. The strong magnetic frustration in Tb@1 is found to arise from the nearly triangular arrangement of Tb3+ ions in its secondary building unit along the chain direction.
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A complete transmetalation has been achieved on a barium metal-organic framework (MOF), leading to the isolation of a new Tb-MOF in a single-crystal (SC) to single-crystal (SC) fashion. It leads to the transformation of an anionic framework with cations in the pore to one that is neutral. The mechanistic studies proposed a core-shell metal exchange through dissociation of metal-ligand bonds. This Tb-MOF exhibits enhanced photoluminescence and acts as a selective sensor for phosphate anion in aqueous medium. Thus, this work not only provides a method to functionalize a MOF that can have potential application in sensing but also elucidates the formation mechanism of the resulting MOF.
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A water stable nanoscale coordination polymer (CP) can detect trinitrophenol (TNP) in an aqueous medium at a record-picogram level (â¼1.66 pg cm(-2)) with a detection limit of 1.66 ppb. This is a simple and low-cost method for the detection of TNP in aqueous media in contact mode, taking advantage of the unique structural arrangement of the as-synthesized CP and the associated photophysical properties.
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We have correlated the structure-property relationship of three manganese-based inorganic-organic hybrid structures. Compound 1, [Mn2(OH-BDC)2(DMF)3] (where BDC = 1,4-benzene dicarboxylic acid and DMF = N,N'-dimethylformamide), contains Mn2O11 dimers as secondary building units (SBUs), which are connected by carboxylate anions forming Mn-O-C-O-Mn chains. Compound 2, [Mn2(BDC)2(DMF)2], contains Mn4O20 clusters as SBUs, which also form Mn-O-C-O-Mn chains. In compound 3, [Mn3(BDC)3(DEF)2] (where DEF = N,N'-diethylformamide), the distorted MnO6 octahedra are linked to form a one-dimensional chain with Mn-O-Mn connectivity. The magnetic properties were investigated by means of magnetization and heat capacity measurements. The temperature dependent magnetic susceptibility of all the three compounds could be nicely fitted using a one-dimensional S = 5/2 Heisenberg antiferromagnetic chain model and the value of intra-chain exchange coupling (J/k(B)) between Mn(2+) ions was estimated to be â¼1.1 K, â¼0.7 K, and â¼0.46 K for compounds 1, 2, and 3, respectively. Compound 1 does not undergo any magnetic long-range-order down to 2 K while compounds 2 and 3 undergo long-range magnetic order at T(N) ≈ 4.2 K and ≈4.3 K, respectively, which are of spin-glass type. From the values of J/k(B) and T(N) the inter-chain coupling (J(â¥)/k(B)) was calculated to be about 0.1J/k(B) for both compounds 2 and 3, respectively.
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Ligand stabilized water soluble Pt nanoclusters were synthesized and characterized through electrospray ionization mass spectrometry. Glutathione was used as the ligand, and Pt5(SG)10, and Pt6(SG)12 clusters were synthesized. Theoretical investigations found that these clusters do not possess a metal core, but rather are most stable in a ring structure. The clusters are stabilized through the thiol ligands forming a square planar structure around each Pt atom to form a ring. The structural elucidation was confirmed through UV/Vis and IR spectroscopy.
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We have synthesized three Metal-Organic Frameworks (MOFs) in which Zn metal ions form the secondary building unit, and 4,4'-sulfonyldibenzoic acid (SDB) serves as the ligand: [[Zn(DMF)(SDB)](DMF), 1, [Zn(3)(DMF)(3)(SDB)(3)](DMF), 2 and [Zn(3)(OH)(2)(SDB)(2)] (DMF)(2), 3, where DMF = dimethyl formamide]. Compound contains a paddle-wheel type Zn dimer, compound contains a Zn trimer motif, and contains a one-dimensional Zn-OH-Zn chain. These building units may be considered to be Zn clusters. We have measured and theoretically calculated the band gap energy and by theoretical investigations we found that the cluster size plays an important role in the band gap energy, however additional effects are observed. The larger cluster size corresponds to a larger band gap energy, however the cavity of the trimer based compound (2) traps a solvent molecule that decreases the band gap energy.
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The crystal growth rate and morphology can be modulated by tuning the ratio of the solvent in mixed solvents during synthesis. We present here a solvothermal method to synthesize a Cd-FDC based metal-organic framework with different morphologies by tuning the ratio of water in the DMF-water mixed solvent system without adding any other additives. With the increasing water volume ratio a series of crystals with different morphologies were synthesized. Among these we have isolated two single crystal structures, [Cd3(FDC)3(DMF)4(H2O)], and [DMA]2[Cd3(FDC)4]·2H2O, . Compound was synthesized from DMF with small amounts of water while was formed from 25 vol% of water in the DMF-water mixed solvent. Compound contains trimer clusters as building units, which are linked by the furan dicarboxylate ligand to form a two-dimensional structure. Compound also contains trimer clusters which are linked to each other to form a one-dimensional chain with the Cd-O-Cd linkage. This one-dimensional chain in turn is connected by the furan dicarboxylate ligand to form a three-dimensional structure. All these structures are characterized by SEM, XRD, TGA and IR. We have measured the band gap energy and measurements show that the values are decreasing from to . The lower band gap energy of may be due to the presence of infinite Cd-O-Cd linkages which split the states of the conduction band and reduces the band gap energy.