371 research outputs found

    Kratom: The analytical challenge of an emerging herbal drug

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    Mitragyna speciosa or kratom is emerging worldwide as a “legal” herbal drug of abuse. An increasing number of papers is appearing in the scientific literature regarding its pharmacological profile and the analysis of its chemical constituents, mainly represented by alkaloids. However, its detection and identification are not straightforward as the plant material is not particularly distinctive. Hyphenated techniques are generally preferred for the identification and quantification of these compounds, especially the main purported psychoactive substances, mitragynine (MG) and 7-hydroxymitragynine (7-OH-MG), in raw and commercial products. Considering the vast popularity of this recreational drug and the growing concern about its safety, the analysis of alkaloids in biological specimens is also of great importance for forensic and toxicological laboratories. The review addresses the analytical aspects of kratom spanning the extraction techniques used to isolate the alkaloids, the qualitative and quantitative analytical methods and the strategies for the distinction of the naturally occurring isomers

    Magnetic Levitation Patterns of Microfluidic-Generated Nanoparticle–Protein Complexes

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    Magnetic levitation (MagLev) has recently emerged as a powerful method to develop diagnostic technologies based on the exploitation of the nanoparticle (NP)–protein corona. However, experimental procedures improving the robustness, reproducibility, and accuracy of this technology are largely unexplored. To contribute to filling this gap, here, we investigated the effect of total flow rate (TFR) and flow rate ratio (FRR) on the MagLev patterns of microfluidic-generated graphene oxide (GO)–protein complexes using bulk mixing of GO and human plasma (HP) as a reference. Levitating and precipitating fractions of GO-HP samples were characterized in terms of atomic force microscopy (AFM), bicinchoninic acid assay (BCA), and one-dimensional sodium dodecyl sulfate–polyacrylamide gel electrophoresis (1D SDS-PAGE), and nanoliquid chromatography–tandem mass spectrometry (nano-LC-MS/MS). We identified combinations of TFR and FRR (e.g., TFR = 35 μL/min and FRR (GO:HP) = 9:1 or TFR = 3.5 μL/min and FRR (GO:HP) = 19:1), leading to MagLev patterns dominated by levitating and precipitating fractions with bulk-like features. Since a typical MagLev experiment for disease detection is based on a sequence of optimization, exploration, and validation steps, this implies that the optimization (e.g., searching for optimal NP:HP ratios) and exploration (e.g., searching for MagLev signatures) steps can be performed using samples generated by bulk mixing. When these steps are completed, the validation step, which involves using human specimens that are often available in limited amounts, can be made by highly reproducible microfluidic mixing without any ex novo optimization process. The relevance of developing diagnostic technologies based on MagLev of coronated nanomaterials is also discussed

    Peptidomic approach for the identification of peptides with potential antioxidant and anti-hyperthensive effects derived from Asparagus by-products

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    Asparagus waste represents products of great interest since many compounds with high biological value are located in the lower portion of the spears. The extraction of bioactive compounds from asparagus by-products is therefore crucial for the purpose of adding value to these by-products. In this paper, bioactive peptides from asparagus waste were extracted, digested, purified and identified. In particular, Alcalase® was chosen as the enzyme to use to obtain protein hydrolysate due to its low cost and, consequently, the possibility of implementing the method on a large scale. In order to simplify the peptide extract to reach better identification, the hydrolysate was fractionated by reversed-phase chromatography in 10 fractions. Two tests were carried out for antioxidant activity (ABTS-DPPH) and one for antihypertensive activity (ACE). Fractions with a higher bioactivity score were identified by peptidomics technologies and screened for bioactivity with the use of bioinformatics. For ACE-inhibitor activity, two peptides were synthetized, PDWFLLL and ASQSIWLPGWL, which provided an EC50 value of 1.76 µmol L-1 and 4.02 µmol L-1, respectively. For the antioxidant activity, by DPPH assay, MLLFPM exhibited the lowest EC50 value at 4.14 µmol L-1, followed by FIARNFLLGW and FAPVPFDF with EC50 values of 6.76 µmol L-1 and 10.01 µmol L-1, respectively. A validation of the five identified peptides was also carried out. The obtained results showed that peptides obtained from asparagus by-products are of interest for their biological activity and are suitable for being used as functional ingredients

    Surface evidence of active tectonics along the Pergola-Melandro fault: a critical

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    The Pergola-Melandro basin (southern Apennines) is characterized by a below-average release of seismic energy within a wider earthquake-prone region. In fact, it is placed between the maximum intensity areas of two of the most destructive earthquakes reported in the Italian seismic catalogue: the M ≥ 7.0 Agri Valley earthquake in 1857 and the Ma = 6.9 Irpinia earthquake in 1980. In this work, we present geomorphologic analysis, electrical resistivity surveys and field data, including paleoseismologic evidence, that provided the first direct constraints on the presence of a ~20 km long, seismogenic fault at the western border of the Pergola-Melandro basin. We also obtained geological information on the recent deformation history of the Pergola-Melandro fault that indicates the occurrence of at least four surface faulting earthquakes since Late Pleistocene age. The empirical relationships linking fault length and magnitude would assign to the Pergola- Melandro fault an event of M ≥ 6.5. These new data have important implication on the seismic hazard assessment of this sector of the Apennines, that also includes large cities such as Potenza, about 20 km far from the recognized Pergola-Melandro fault, and highlight the relevance of the geological approach in areas where the seismological records are poor. Finally, we discuss the Pergola-Melandro fault within the regional seismotectonic context. In particular, this fault belongs to the system of normal faults with an apenninic orientation, both NE and SW dipping, that accommodate the NE- crustal extension taking place in the area. Nearby faults, similarly oriented but with opposite dip, may coexist whether linked by secondary faults that act as slip transfer structures. This complex system of active faults would be more realistic than to consider a narrow band of faults, running along the belt axis, with an homogenous geometry and, moreover, more consistent with the high extension rate measured by historical earthquakes and geodetic data

    Surface evidence of active tectonics along the Pergola-Melandro

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    The Pergola-Melandro basin (southern Apennines) is characterized by a below-average release of seismic energy within a wider earthquake-prone region. In fact, it is placed between the maximum intensity areas of two of the most destructive earthquakes reported in the Italian seismic catalogue: theM≥7.0 Agri Valley earthquake in 1857 and the Ms = 6.9 Irpinia earthquake in 1980. In thiswork, we present geomorphologic analysis, electrical resistivity surveys and field data, including paleoseismologic evidence, that provided the first direct constraints on the presence of a∼20 kmlong, seismogenic fault at the western border of the Pergola-Melandro basin. We also obtained geological information on the recent deformation history of the Pergola-Melandro fault that indicates the occurrence of at least four surface faulting earthquakes since Late Pleistocene age. The empirical relationships linking fault length and magnitude would assign to the Pergola-Melandro fault an event of M≥6.5. These new data have important implication on the seismic hazard assessment of this sector of the Apennines, that also includes large cities such as Potenza, about 20 km far from the recognized Pergola-Melandro fault, and highlight the relevance of the geological approach in areas where the seismological records are poor. Finally, we discuss the Pergola-Melandro fault within the regional seismotectonic context. In particular, this fault belongs to the system of normal faults with an apenninic orientation, both NE and SW dipping, accommodating the NE-crustal extension taking place in the area. Nearby faults, similarly oriented but with opposite dip, may coexist whether linked by secondary faults that act as slip transfer structures. This complex system of active faults would be more realistic than a narrow band of faults running along the belt axis with an homogenous geometry, and moreover, it is more consistent with the high extension rate measured by historical earthquakes and geodetic data

    The Vallo di Diano Range-Bounding Fault-System (Southern Italy): New Evidence of Recent Activity From High-Resolution Seismic Profiling

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    The Vallo di Diano is the largest intermountain basin in the Southern Apennines (Italy). The basin evolution was controlled by the Quaternary activity of a range-bounding, SW-dipping normal fault system located to the east (Vallo di Diano Fault System, VDFS). Geological and oil industry data define the sin-sedimentary activity of the VDFS up to the Middle Pleistocene. However, commercial profiles do not resolve the shallower, eastern portion of the basin, due to strong lateral heterogeneities and unfavourable surface conditions. Therefore, Late Pleistocene-Holocene activity of the VDFS and its seismogenic potential are still uncertain. To better constrain the shallow structure of the basin, we performed four high-resolution seismic surveys, along its eastern side, where slope breccias and fans cover the Mesozoic carbonate bedrock and bury the VDFS. We also investigated some NW-trending flexures affecting Late Pleistocene fans, that we had previously detected and dubitatively ascribed to recent faulting. Seismic data were acquired with a dense wide-aperture geometry. Two high-resolution (HR) NE-trending profiles, about 1.5 km long, were collected using respectively 5 m and 10 m spaced receivers and sources. Two very high-resolution (VHR) NE-trending profiles, 400 and 350 m long, with densely spaced sources (4 m) and receivers (2 m) were also collected. HR profiling was aimed at imaging alluvial fan thickness and morphology of the underlying carbonate bedrock. VHR surveys targeted the flexures and their possible origin. All lines were acquired with a HR vibroseis source, except for the shortest profile, where we used a buffalo-gun, better suited for very near-surface imaging (z < 50 m depth). Seismic imaging consists of reflectivity images obtained by CDP-processing of reflection data complemented by Vp images obtained by multi-scale seismic tomography. The stack sections illuminated the basin down to 0.4-0.5 s TWT and reveal an array of high-angle, generally SW-dipping faults dissecting the bedrock and the alluvial fans. Faulting created accommodation space in the hanging-wall and displaced the different fan generations. Clear reflection truncations in the stack-sections correspond to significant Vp lateral changes in the tomographic images. VHR tomography is well defined along the shortest line down to 40 m depth, where two steps within slope breccias are visible. Moreover, two low-velocity wedges (colluvial packages) are imaged in the near surface (5-20 m depth). These data support recent faulting consistently with surface geomorphic features. We interpret these fault structures as splays of the range bounding master fault. Comparison with commercial reflection profiles nearby reveals a great improvement in seismic imaging achieved by HR surveys, which allow a detailed seismostratigraphic analysis of the basin.UnpublishedSan Francisco (CA), Moscone West, Howard Street3.2. Tettonica attivaope

    Evaluation of the carotenoid and fat-soluble vitamin profile of industrial hemp inflorescence by liquid chromatography coupled to mass spectrometry and photodiode-array detection

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    Industrial hemp (Cannabis sativa L.) is a plant matrix whose use is recently spreading for pharmaceutical and nutraceutical purposes. Detailed characterization of hemp composition is needed for future research that further exploits the beneficial effects of hemp compounds on human health. Among minor constituents, carotenoids and fat-soluble vitamins have largely been neglected to date despite carrying out several biological activities and regulatory functions. In the present paper, 22 target carotenoids and fat-soluble vitamins were analyzed in the inflorescences of seven Italian industrial hemp varieties cultivated outdoor. The analytes were extracted by cold saponification to avoid artifacts and analyzed by high-performance liquid chromatography coupled with Selected reaction monitoring mass spectrometry. Phytoene, phytofluene, and all-trans-β-carotene were the most abundant in all analyzed samples (31–55 μg g−1, 11.6–29 μg g−1, and 7.3–53 μg g−1, respectively). Besides the target analytes, liquid chromatography coupled with photodiode-array detection allowed us to tentatively identify several other carotenoids based on their retention behavior and UV–vis spectra with the support of theoretical rules and data in the literature. To the best of our knowledge, this is the first comprehensive characterization of carotenoids and fat-soluble vitamins in industrial hemp inflorescence

    Untargeted cannabinomics reveals the chemical differentiation of industrial hemp based on the cultivar and the geographical field location

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    Cannabis sativa has long been harvested for industrial applications related to its fibers. Industrial hemp cultivars, a botanical class of Cannabis sativa with a low expression of intoxicating Δ9-tetrahydrocannabinol (Δ9-THC) have been selected for these purposes and scarcely investigated in terms of their content in bioactive compounds. Following the global relaxation in the market of industrial hemp-derived products, research in industrial hemp for pharmaceutical and nutraceutical purposes has surged. In this context, metabolomics-based approaches have proven to fulfill the aim of obtaining comprehensive information on the phytocompound profile of cannabis samples, going beyond the targeted evaluation of the major phytocannabinoids. In the present paper, an HRMS-based metabolomics study was addressed to seven distinct industrial hemp cultivars grown in four experimental fields in Northern, Southern, and Insular Italy. Since the role of minor phytocannabinoids as well as other phytocompounds was found to be critical in discriminating cannabis chemovars and in determining its biological activities, a comprehensive characterization of phytocannabinoids, flavonoids, and phenolic acids was carried out by LC-HRMS and a dedicated data processing workflow following the guidelines of the metabolomics Quality Assurance and Quality Control Consortium. A total of 54 phytocannabinoids, 134 flavonoids, and 77 phenolic acids were annotated, and their role in distinguishing hemp samples based on the geographical field location and cultivar was evaluated by ANOVA-simultaneous component analysis. Finally, a low-level fused model demonstrated the key role of untargeted cannabinomics extended to lesser-studied phytocompound classes for the discrimination of hemp samples

    Using Image Planes on DC Motors to filter High Frequency Noise,”

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    Abstract-Traditionally, DC motors have only been filtered for narrow frequency bands of interest, such as the AM and FM bands. However, as more electronic devices are implemented in consumer applications such as automobiles, requirements now demand filtering from kilohertz to several gigahertz. Capacitors, inductors, and ferrites characteristically are used to filter narrow frequency bands. They are limited by their size and parasitics for broadband performance and are cost prohibitive in many DC motor applications that require broadband performance. The purpose of this paper is to investigate an alternative cost effective approach for broadband filtering performance. Image planes have been shown to provide good results on PCB applications for reducing radiated emissions. This paper examines the possibility of using image theory for filtering DC motors
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