Probing orographic controls in the Himalayas during the monsoon using satellite imagery

The linkages between the space-time variability of observed clouds, rainfall, large-circulation patterns and topography in northern India and the Himalayas were investigated using remote sensing data. The research purpose was to test the hypothesis that cloudiness patterns are dynamic tracers of rainstorms, and therefore their temporal and spatial evolution can be used as a proxy of the spatial and temporal organization of precipitation and precipitation processes in the Himalayan range during the monsoon. The results suggest that the space-time distribution of precipitation, the spatial variability of the diurnal cycle of convective activity, and the terrain (landform and altitudinal gradients) are intertwined at spatial scales ranging from the order of a few kms (1–5km) up to the continental-scale. Furthermore, this relationship is equally strong in the time domain with respect to the onset and intra-seasonal variability of the monsoon. Infrared and microwave imagery of cloud fields were analyzed to characterize the spatial and temporal evolution of mesoscale convective weather systems and short-lived convection in Northern India, the Himalayan range, and in the Tibetan Plateau during three monsoon seasons (1999, 2000 and 2001). The life cycle of convective systems suggests landform and orographic controls consistent with a convergence zone constrained to the valley of the Ganges and the Himalayan range, bounded in the west by the Aravalli range and the Garhwal mountains and in the East by the Khasi Hills and the Bay of Bengal, which we call the Northern India Convergence Zone (NICZ). The NICZ exhibits strong night-time activity along the south-facing slopes of the Himalayan range, which is characterized by the development of short-lived convection (1–3h) aligned with protruding ridges between 1:00 and 3:00 AM. The intra-annual and inter-annual variability of convective activity in the NICZ were assessed with respect to large-scale synoptic conditions, monsoon activity in the Bay of Bengal, and the modulating role of orography. Empirical orthogonal function (EOF) and canonical correlation (CC) analysis suggest that joint modes of variability of monsoon weather and topography, which we call orographic land-atmosphere interactions, modulate the space-time variability of cloudiness in the region. Finally, scaling analysis of cloudiness suggests three different scaling regimes of orographic land-atmosphere interactions: 1) a synoptic-scale regime (≥70-80km); 2) an orographic meso–β regime (30–70km) associated with the succession of wide valleys and bulky terrain features; and 3) an orographic meso–α regime (≤30km) associated with the complex succession of protruding south-facing ridges and narrow valleys that characterize the Himalayan foothills between altitudes of 3000 and 5000m elevations

Insights on the extraction performance of Alkanediols and Glycerol: ssing Juglans regia L. Leaves as a source of bioactive compounds

Glycerol and alkanediols are being studied as alternative solvents to extract phytochemicals from plant material, often as hydrogen bond donors in deep eutectic solvents (DESs). Many of those alcohols are liquid at room temperature, yet studies of their use as extraction solvents are scarce. In this work, glycerol and a series of alkanediols (1,2-ethanediol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,2-pentanediol, 1,5-pentanediol, and 1,2-hexanediol) were studied for the extraction of phenolic compounds from Juglans regia L. leaves, a rich source of this class of bioactive compounds. The extraction yield was quantified, and the bioactivity of both extracts and pure solvents was evaluated by measuring the anti-inflammatory and cytotoxic activities. The solvents showing the best combined results were 1,2 and 1,3-propanediol, as their extracts presented a high amount of phenolic compounds, close to the results of ethanol, and similar cytotoxicity against cervical carcinoma cells, with no impact on non-tumor porcine liver cells in the studied concentration range. On the other hand, none of the extracts (and solvents) presented anti-inflammatory activity. Overall, the results obtained in this work contribute to the study of alternative solvents that could potentially be used also as formulation media, highlighting the importance of walnut leaves as a source of bioactive compounds.This work was developed within the scope of the CIMO-Mountain Research Center UIDB/00690/2020 and CICECO-Aveiro Institute of Materials UIDB/50011/2020 & UIDP/50011/2020 projects, both financed by national funds through the Portuguese Foundation for Science and Technology (FCT)/MCTES, as well as POCI-01-0145-FEDER-006984 (LA LSRE-LCM), funded by ERDF, through POCI-COMPETE2020 and FCT. The authors also thank the national funding from FCT, P.I., through the individual scientific employment program-contract for L. Barros and R. C. Calhelha and V. Vieira’s grant (SFRH/BD/108487/2015). Support was also provided by project AllNat—POCI-01-0145-FEDER-030463 (PTDC/EQU-EPQ/30463/2017), funded by FEDER funds through COMPETE2020—Programa Operacional Competitividade e Internacionalização (POCI), and by national funds through the Foundation for Science and Technology (FCT/MCTES).info:eu-repo/semantics/publishedVersio

Tailloring deep eutectic solvents for the extraction of valuable compounds from natural sources using choline chloride and carboxylic acids mixtures: optimization of the extraction of phenolic compounds from Juglans regia L. leaves

Phenolic compounds are a wide group of plant secondary metabolites with increasing interest due to their antioxidant ability and marked effects on oxidative processes related to several chronic diseases. Nowadays, they find applications in pharmaceutical products, functional foods and natural-based cosmetics. Therefore, the extraction and identification of these valuable compounds from different plants have become a major research area. Nevertheless, conventional solid-liquid extraction of phenolics usually involves the use of flammable, toxic and volatile organic solvents. Deep eutectic solvents (DES) are gaining much interest as alternative solvents to extract valuable compounds from natural matrices. DES can be considered “designer solvents” due to the possibility of combining different HBA (hydrogen bond acceptor) and HBD (hydrogen bond donor) to obtain solvents with specific properties to the target application. In this study, DES composed of choline chloride (CC) and different groups of organic acids were prepared, in order to extract phenolic compounds from leaves of Juglans regia L. (walnut leaves). The initial screening involved monocarboxylic (acetic, propionic, butyric, valeric, lactic and glycolic acids), dicarboxylic (malonic, glutaric and malic acids), tricarboxylic (citric) and aromatic acids (phenylacetic acid, 3-phenylpropanoic acid). The initial extraction conditions were: 50 ºC, 60 min extraction time and 20% water content. The main phenolic compounds (neochlorogenic acid, quercetin 3-O-glucoside and quercetin O-pentoside) were quantified by high performance liquid chromatography coupled to a diode de array detector (HPLC-DAD at 280 and 370 nm). Higher extraction yields were obtained using CC:butyric acid and CC:3-phenylpropanoic acid. For these systems, the stoichiometric ratio of HBA and HBD as well as the water content in the DES solutions were further evaluated. Better results were obtained using DES compared to the conventional water + ethanol mixed solvent. The present work contributes to the valorization of walnut leaves extracts using alternative solvents that could be tailored for potential applications in the food and pharmaceutical areas.The authors thank the Foundation for Science and Technology (FCT, Portugal) and FEDER under Programme PT2020 for financial support to CIMO (UID/AGR/00690/2013), L. Barros (SFRH/BPD/107855/2015) and V. Vieira (SFRH/BD/108487/2015) grants. To POCI-01-0145-FEDER-006984 (LA LSRE-LCM), funded by ERDF, through POCI-COMPETE2020 and FCT. To Xunta de Galicia for financial support for the post-doctoral researcher of M.A. Prieto.info:eu-repo/semantics/publishedVersio

Enhanced extraction of phenolic compounds using choline chloride based deep eutectic solvents from Juglans regia L.

The extraction of phenolic compounds from walnut leaves (Juglans regia L.) was optimized using heat-assisted extraction and deep eutectic solvents based on choline chloride and carboxylic acids. A preliminary solvent screening was performed using a selected group of carboxylic acids as hydrogen bond donors, showing that the highest extraction yield of phenolic compounds was obtained using choline chloride mixtures with butyric or phenylpropionic acid at a mole ratio 1:2, with 20% of water (w/w). The extraction conditions (time, temperature and water proportion) were then optimized by an experimental design, assisted by response surface methodology. To evaluate the response, the three most abundant compounds identified by HPLC (neochlorogenic acid, quercetin 3-O-glucoside and quercetin O-pentoside) were quantified. Additionally, the solid/liquid ratio effect at the optimal conditions, in dose-response format, was studied in view of its upscale, not showing any significant decrease until 140 g/L. The results here presented provide valuable information towards the design of a process in a pre-industrial form for the extraction of phenolic compounds from J. regia leaves using deep eutectic solvents.The authors thank the Foundation for Science and Technology (FCT, Portugal) and FEDER under Programme PT2020 for financial support to CIMO (UID/AGR/00690/2013), V. Vieira (SFRH/BD/108487/2015) grant and L. Barros contract. To project POCI-01-0145-FEDER-006984 – Associate Laboratory LSRE-LCM funded by FEDER through COMPETE2020 – Programa Operacional Competitividade e Internacionalização (POCI) – and by national funds through FCT – Fundação para a Ciência e a Tecnologia. To project CICECO‐Aveiro Institute of Materials POCI‐01‐0145‐FEDER‐007679 (FCT Ref. UID/ CTM/50011/2013), financed by national funds through the FCT/MEC and when appropriate co‐financed by FEDER under the PT2020 Partnership Agreement. This work is funded by the European Structural and Investment Funds (FEEI) through POCI, within the scope of Project POCI nº 030463. To Xunta de Galicia for financial support for the postdoctoral researcher of M.A. Prieto.info:eu-repo/semantics/publishedVersio

Noise Sources in Photometry and Radial Velocities

The quest for Earth-like, extrasolar planets (exoplanets), especially those located inside the habitable zone of their host stars, requires techniques sensitive enough to detect the faint signals produced by those planets. The radial velocity (RV) and photometric transit methods are the most widely used and also the most efficient methods for detecting and characterizing exoplanets. However, presence of astrophysical "noise" makes it difficult to detect and accurately characterize exoplanets. It is important to note that the amplitude of such astrophysical noise is larger than both the signal of Earth-like exoplanets and state-of-the-art instrumentation limit precision, making this a pressing topic that needs to be addressed. In this chapter, I present a general review of the main sources of noise in photometric and RV observations, namely, stellar oscillations, granulation, and magnetic activity. Moreover, for each noise source I discuss the techniques and observational strategies which allow us to mitigate their impact.Comment: 11 pages, 2 tables, Lecture presented at the IVth Azores International Advanced School in Space Sciences on "Asteroseismology and Exoplanets: Listening to the Stars and Searching for New Worlds" (arXiv:1709.00645), which took place in Horta, Azores Islands, Portugal in July 201

Apoptosis induction by Pleurotus sajor-caju (Fr.) Singer extracts on colorectal cancer cell lines

Pleurotus sajor-caju (PSC) is an edible mushroom used in food supplements, presenting antitumor properties through induction of cell death pathways. The PSC potential against colorectal cancer was analyzed by exposing HCT116wt cells to different PSC extracts. The PSC n-hexane extract (PSC-hex) showed the highest cytotoxicity effect (IC50 value 0.05 mg/mL). The observed cytotoxicity was then associated to apoptosis-promoting and cell cycle-arrest pathways. PSC-hex was able to induce apoptosis related to breakdown of mitochondrial membrane potential and ROS generation. The absence of cytotoxicity in HTC116-p53 and HTC116-Bax cells, alongside with an increase in p53, Bax and Caspase-3 expression, and decrease in Bcl-2 expression, supports that the proapoptotic effect is probably induced through a p53 associated pathway. PSC-hex induced cell cycle arrest at G2/ M in HCT116wt without cytotoxicity in HTC116-p21 cells. These findings suggest that a p21/p53 cell cycle regulation pathway is probably disrupted by compounds present on PSC-hex. Identification of the major components was then performed with ergosta-5,7,22-trien-3β-ol representing 30.6% of total weight. In silico docking studies of ergosta-5,7,22-trien-3β against Bcl-2 were performed and results show a credible interaction with the Bcl-2 hydrophobic cleft. The results show that PSC-hex can be used as supplementary food for adjuvant therapy in colorectal carcinoma.The authors thank Dr. Larsen (Institut National de la Santé et de la Recherche Médicale) for the gift of HCT116-Bax, HCT116-p21 and HCT116-p53 cells. The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) and FEDER under Programme PT2020 for financial support to CIMO (UID/AGR/00690/2013) and L. Barros contract. T.C. Finimundy thanks CAPES Foundation, Ministry of Education of Brazil (CAPES fellow, process number 88881.134581/ 2016–01). This work is supported by a grant from Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) and Fundaçãoinfo:eu-repo/semantics/publishedVersio

Supported ionic liquids as customizable materials to purify immunoglobulin G

Over the past few years, antibodies such as immunoglobulin G, IgG, have increased their market share as alternative therapeutics. However, their production at high purity levels is still costly due to the absence of a cost-effective platform for their recovery and purification from the complex biological media in which they are produced. This work describes, for the first time, that materials modified with ionic liquids (ILs) can be designed for the effective capture and purification of antibodies from complex matrices, allowing both the selective adsorption of IgG or the selective adsorption of other proteins present in the media. The best results correspond to IgG with 59 % of yield and 84 % of purity in the aqueous solution, and IgG with 76 % of yield and 100 % of purity on the surface of one SIL due to the selective adsorption of IgG from human serum. The best conditions and materials were then applied to other IgG-containing matrices, namely rabbit serum and Chinese hamster ovary (CHO) cell culture supernatants, proving the robustness of the developed strategy. Furthermore, it is demonstrated that the secondary structure of IgG is preserved during the purification process and that these antibodies remain biologically active. In summary, it is shown that by only changing the IL chemical structure at the material surface it is possible to selectively adsorb IgG or to adsorb other proteins leaving IgG in solution. These findings prove that SILs are customizable materials with future potential to act in the flow-through or bind-andelute modes. Therefore, SILs can be envisioned as potential chromatographic columns capable of substituting the high-cost commercial chromatographic columns based on biological ligands currently used to purify IgG.publishe

Multifunctions of Pleurotus sajor-caju (Fr.) Singer: a highly nutritious food and a source for bioactive compounds

A study with Pleurotus sajor-caju was conducted to: evaluate the nutritional and chemical composition of the fruiting bodies; optimize the preparation of bioactive phenolic extracts; and characterize the optimized extract in terms of bioactive compounds and properties. P. sajor-caju revealed an equilibrated nutritional composition with the presence of hydrophilic (sugars and organic acids) and lipophilic (tocopherols and PUFA) compounds. p-Hydroxybenzoic, p-coumaric and cinnamic acids were identified in the extract obtained with ethanol (30 g/l ratio) at 55 °C for 85 min. This extract showed antioxidant properties (mainly reducing power and lipid peroxidation inhibition), antibacterial activity against MRSA and MSSA and cytotoxicity against NCI-H460, MCF-7 and HeLa. Furthermore, as the extract showed capacity to inhibit NO production in Raw 264.7 macrophages, molecular docking studies were performed to provide insights into the anti-inflammatory mechanism of action, through COX-2 inhibition by the phenolic acids identified.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) and FEDER under Program PT2020 for financial support to CIMO (UID/AGR/00690/2013) and for L. Barros and R. Calhelha contracts. T.C. Finimundy thanks CAPES Foundation, Ministry of Education of Brazil (CAPES fellow, process number 88881.134581/2016-01). To Xunta de Galicia for financial support for the post-doctoral researcher of M.A. Prieto.info:eu-repo/semantics/publishedVersio