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... Since 2007, most people of the world live in cities. Urban agriculture, and more specifically urban horticulture may allow improvements in food supply and reduce the city ecological footprint. Furthermore, gardening practices are associated with social and therapeutic effects. In the last decades, as a consequence of the increased awareness on its related benefits, urban horticulture has assumed a ...
case studies; developing countries; domestic markets; entrepreneurship; farmers; farmers' markets; livelihood; nongovernmental organizations; organic foods; organic production; rural communities; Europe; North America; Peru
Abstract:
... Studies of alternative food networks have proliferated in Europe and North America while relatively little attention has been paid to similar networks in the global South. An organic farmers market in Lima, Peru, serves as a case study to examine developments in the domestic market for organic produce in Peru. Drawing from interview data and participant observations with pioneering organic farmers ...
advocacy; consumers (people); farm labor; females; qualitative analysis; restaurants; risk; slaughter; social inequality; social networks
Abstract:
... Agrifood movement literature largely represents food system labor through images, descriptions, and depictions of farm workers and other agriculture-related labor, such as slaughtering and meatpacking. Although engaging in a holistic dialogue that considers the continuum of labor abuse across the food system may be a difficult task, privileging production-oriented food system labor reinforces what ...
business planning; case studies; crops; cultivars; farmers; fruits; mangoes; markets; monopoly; protected designation of origin; India
Abstract:
... Intellectual property is all about monopoly in the market place and harnessing the maximum economic benefits by exercising the monopoly. Monopoly in the shape of goodwill, reputation and demand becomes the most formidable under the banner of Geographical Indication (GI) as GI is a monopoly of a guild unlike a private monopoly. Uttar Pradesh is a sacred land as the birth place of Lord Ram and Lord ...
... Since 1978 the development of triploid hybrids by crossing monoembryonic 2x female parents with 4x male parents has been the successful breeding strategy carried out by the CRA-ACM. Through this strategy hybrids issued in the past allowed the obtainment of seedless fruits, in some cases pigmented, of good size and maturation in different periods. In 2011 other two promising hybrids, âSweet Sicil ...
Pestalotiopsis; X-ray diffraction; alkaloids; antiviral properties; chemical reactions; chemical structure; corals; fungi; high performance liquid chromatography; inhibitory concentration 50; spectroscopy
Abstract:
... A pair of new enantiomeric alkaloid dimers, (+)- and (−)-pestaloxazine A (1), with an unprecedented symmetric spiro[oxazinane-piperazinedione] skeleton, consisting of 22 carbons and 12 heteroatoms, were isolated from a Pestalotiopsis sp. fungus derived from a soft coral. Separation of the enantiomeric alkaloid dimers was achieved by chiral HPLC. Their structures including absolute configurations w ...
catalysts; chemical reactions; chemical structure; organic chemistry; organic compounds; salts
Abstract:
... A new efficient and highly recyclable organocatalyst has been developed for asymmetric cross-aldol reactions under neat conditions in ketone–ketone, ketone–aldehyde, and aldehyde–aldehyde systems. The catalyst features two prolinamide fragments and a C₂-symmetrical (1,2-diaminoethane-1,2-diyl)bis(N-methylpyridinium) group. The catalyst retained high activity and excellent stereoselection over the ...
... Dental plaque is a highly diverse biofilm, which has an important function in maintenance of oral and systemic health but in some conditions becomes a cause of oral diseases. In addition to mechanical plaque removal, current methods of dental plaque control involve the use of chemical agents against biofilm pathogens, which however, given the complexity of the oral microbiome, is not sufficiently ...
... In order to produce highly purified (1→3)-β-d-glucan oligosaccharides ((1→3)-β-d-GOS) monomers, a hydrophilic interaction liquid chromatography (HILIC) system with X-Amide stationary phase was performed. Nine (1→3)-β-d-GOS monomers with degree of polymerization (DP) from 2 to 10 were successfully separated. Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) ...
... Recombinant Escherichia coli, carrying the crtE, crtB, crtI, crtY, and crtZ genes from the bacterium Pantoea ananatis in addition to the Haematococcus pluvialis idi gene, can dominantly produce zeaxanthin. Vigorous rotary-shaking culture of the recombinant cells to promote strong aeration led to the production of two structurally similar polar carotenoids [1 (3.7%) and 2 (2.9%)] and eschscholtzxan ...
... Ternary oxides have gained increasing attention due to their potential use as solid lubricants at elevated temperatures. In this work, the tribological properties of three ternary oxidesAgTaO₃, CuTaO₃, and CuTa₂O₆were studied using a combination of density-functional theory (DFT), molecular dynamics (MD) simulations with newly developed empirical potential parameters, and experimental measuremen ...
... (Carboxy-3-oxopropylamino)-3-propylsilylcellulose (COPAPSC), a novel organocatalyst, has been prepared by a synthesis grafting of –COOH functionalized organosilanes on a cellulose using surface hydroxyl groups as anchor points. The –CO₂H group-functionalized cellulose was synthesized via the consecutive surface functionalization with 3-aminopropyltriethoxysilane (3-APTES) followed by the condensat ...
... The astonishing efficiency with which living organisms build complex molecules from simple starting materials has inspired chemists for centuries. Among the synthetic strategies that nature uses to achieve this efficiency, the combination of several enzymatic transformations in cascading sequences is of outstanding importance. With the rise of biocatalysis, researchers now have the tools at hand t ...
... Efficient access to α,α′-diacetoxy ketones has been developed from ethynylcarbinols and PhI(OAc)₂. A plausible mechanism for this was proposed on the basis of experimental studies. The usefulness of α,α′-diacetoxy ketone products has been documented, and glycerol derivatives can be easily synthesized in good yields via a one-pot reaction. ...
... A facile approach is reported to synthesize (Fe,Co)@nitrogen-doped graphitic carbon (NGC) nanocubes (NCs) via the pyrolysis of polydopamine-encapsulated Fe₃[Co(CN)₆]₂ NCs at 700 °C. Besides the comparable catalytic activity for oxygen reduction reaction (ORR) to the Pt/C catalyst, it showed much more outstanding catalytic selectivity and superior durability. ...
... A recent study links N-terminal acetylation and N-end rule degradation to blood pressure regulation. N-terminal mutants of Rgs2, a key G-protein regulator, are differentially processed by N-terminal acetyltransferases and the two branches of the N-end rule pathway. This leads to an imbalance in the signaling governing blood pressure. ...
... A self-powered active strain sensor based on well-aligned (K,Na)NbO₃ piezoelectric nanofibers is successfully fabricated through the electrospinning and polymer packaging process. The device exhibits a fast, active response to dynamic strain by generating impulsive voltage signal that is dependent on the amplitude of the dynamic strains and the vibration frequency. When the frequency is fixed at 1 ...
... Due to rapidly increasing resistance development against conventional antibiotics, as well as problems associated with diseases either triggered or deteriorated by infection, antimicrobial and anti-inflammatory peptides have attracted considerable interest during the last few years. While there is an emerging understanding of the direct antimicrobial function of such peptides through bacterial mem ...
Morus alba; Morus nigra; antioxidant activity; antioxidants; chlorogenic acid; clones; flavonols; food matrix; leaves; mulberries; new products; pharmaceutical industry; phenolic compounds; phytopharmaceuticals; principal component analysis; value added; Spain
Abstract:
... The (poly)phenolic fingerprint and antioxidant activities of the leaves of white and black mulberry clones grown in Spain, one of the main European producers, were evaluated for the first time in order to examine their phytochemical potential. Data showed that mulberry leaves are rich in caffeoylquinic acids (6.8–8.5 mg/g dw) and flavonols (3.7–9.8 mg/g dw). It was also evidenced that a wide intra ...
... (R)-phenylacetylcarbinol or (R)-PAC is a pharmaceutical precursor of (1R, 2S) ephedrine and (1S, 2S) pseudoephedrine. Biotransformation of benzaldehyde and glucose by pyruvate decarboxylase produces (R)-PAC. This biotransformation suffers from toxicity of the substrate, product [(R)-PAC] and by-product (benzyl alcohol). In the present study, ionic liquid/aqueous biphasic system was employed to enh ...
... Organic thin film transistor (OTFT) devices fabricated by the solution-based QLS technique from a mixed (phthalocyaninato)(porphyrinato) europium complex (TFPP)Eu[Pc(OPh)₈]Eu[Pc(OPh)₈] exhibit air-stable ambipolar performance with mobilities of 6.0 × 10–⁵ cm² V⁻¹ s⁻1 for holes and 1.4 × 10–⁴ cm² V–¹ s–¹ for electrons, respectively. In good contrast, the two-component bilayer heterojunction thin fi ...
acids; buffers; chemical speciation; metal ions; metals; pH; zwitterions
Abstract:
... The use of buffers to maintain the pH within a desired range is a very common practice in chemical, biochemical and biological studies. Among them, zwitterionic N-substituted aminosulfonic acids, usually known as Good’s buffers, although widely used, can complex metals and interact with biological systems. The present work reviews, discusses and updates the metal complexation characteristics of th ...
Herpetogramma; acetates; electroantennography; field experimentation; gas chromatography; males; mass spectrometry; moths; sex pheromones; spectral analysis; virgin females
Abstract:
... The sex pheromone of Herpetogramma submarginale (Swinhoe) was studied by gas chromatography (GC) with electroantennographic detection and GC coupled with mass spectrometry. Two pheromone candidates detected in the gland extracts of females were identified as (Z)-13-hexadecenyl acetate (Z13-16:OAc) and (E)-13-hexadecenyl acetate (E13-16:OAc) in a ratio of 87:13 by mass spectral analysis of the natu ...
... Green leaf volatiles (GLVs), the products of the hydroperoxide lyase (HPL) branch of the oxylipin pathway, play important roles in plant defense responses to both insect pests and pathogens. However, little is known about the role of GLVs in the defense responses of rice to the white-backed planthopper (WBPH, Sogatella furcifera (Horváth)). Here, we found that the rice HPL gene OsHPL3 was upregula ...
... The stereoselective transformation of α-alkoxyacetoaldehydes to the corresponding (Z)-vinyl triflates was achieved by treatment with phenyl triflimide and DBU. The stereochemistry was explained by the “syn-effect,” which was attributed primarily to an σ → π* interaction. The β-alkoxy vinyl triflates obtained were applied to the stereoselective synthesis of structurally diverse (Z)-allylic alcohols ...
Lu Yuanyuan; Xue Yongbo; Liu Junjun; Yao Guangmin; Li Dongyan; Sun Bin; Zhang Jinwen; Liu Yanfei; Qi Changxing; Xiang Ming; Luo Zengwei; Du Guang; Zhang Yonghui
... Three pairs of new 8-O-4′-type dinorneolignan enantiomers, (±)-acortatarinowins A–C (1a/1b–3a/3b), a pair of new 8-O-4′-type (4a/4b) and a pair of rare C7–C8′-type (5a/5b) neolignan enantiomers, (±)-acortatarinowins D and E, and a pair of new furofuran-type lignan enantiomers, (±)-acortatarinowin F (6a/6b), along with two pairs of known lignan enantiomers (7a/7b and 8a/8b), were obtained from the ...
... (+)- and (−)-Sinensilactam A (1), novel hybrid metabolites possessing a unique 2H-pyrrolo[2,1-b][1,3]oxazin-6(7H)-one ring system, were isolated from the fruit bodies of Ganoderma sinensis. The structures of these substances and absolute configurations at their stereocenters were assigned using spectroscopic and computational methods along with X-ray crystallographic analysis. A plausible pathway ...
... This work investigated the blood pressure (BP)-lowering effect of the flavanol (−)-epicatechin in a model of metabolic syndrome. Rats were fed a regular chow diet without (Control) or with 10% (w/v) fructose in the drinking water (high fructose, HF) for 8 weeks. A subgroup of the HF-fed rats was supplemented with (−)-epicatechin 20 mg/kg body weight (HF-EC). Dietary (−)-epicatechin reverted the in ...
... The aim of the present study was to assess the in vitro and in vivo activity of (−)-α-bisabolol (1) against the etiological agents of visceral leishmaniasis. Bone-marrow-derived macrophages were infected with Leishmania infantum or L. donovani promastigotes and incubated with (−)-α-bisabolol at different concentrations. Pentamidine isethionate and meglumine antimoniate were used as reference drugs ...
Western blotting; apoptosis; caspases; cytochrome c; death; diabetes mellitus; flow cytometry; gene expression regulation; glucose; islets of Langerhans; mammals; pathogenesis; patients; public health; reverse transcriptase polymerase chain reaction; risk factors; signal transduction; therapeutics; vitamin D deficiency; China
Abstract:
... Diabetes mellitus is a leading cause of death and disability worldwide, which presents a serious public health crisis in China nowadays. It has been well recognized that excessive β-cell apoptosis is the key pathogenesis of diabetes, of which the mammalian target of rapamycin (mTOR) serves as the critical signaling pathway. Emerging evidence indicates that vitamin D deficiency acts as a potential ...
chemical reactions; crystal structure; organic compounds
Abstract:
... An efficient method for the preparation of 1,1′-dihydroxy-2,2′-biimidazoles via cyclization of α,α′-dinitrones is reported. According to the X-ray crystal structure of the product, one ring adopts the 1-hydroxy form and the other ring exists in the N-oxide form. ...
... A new class of bioorthogonal reagents, 1,2,4-triazines, is described. These scaffolds are stable in biological media and capable of robust reactivity with trans-cyclooctene (TCO). The enhanced stability of the triazine scaffold enabled its direct use in recombinant protein production. The triazine–TCO reaction can also be used in tandem with other bioorthogonal cycloaddition reactions. These featu ...
catalytic activity; gas chromatography-mass spectrometry; isomers; xylene; zeolites
Abstract:
... While 1,2,4-trimethylbenzene (TMB) disproportionation is one of the potential technologies for p-xylene production, its reaction intermediates have been neither experimentally observed nor identified yet. Here we present GC–MS evidence that not only pentamethylated diphenylmethane (5mDPM) derivatives but also hexamethylated diphenylmethane (6mDPM) ones are serving as key reaction intermediates of ...
boron; carbon; moieties; nuclear magnetic resonance spectroscopy; regioselectivity; stable isotopes
Abstract:
... Alkynyl(ferrocenyl)vinylsilanes containing up to three alkynyl units were prepared and treated with 9-borabicyclo[3.3.1]nonane (9-BBN). All reactions proceeded in the beginning by regioselective 1,2-hydroboration of the vinyl group, with boron attached to the terminal carbon. This was followed by intra-molecular 1,1-carboboration, leading to fused silacarbacycles, depending on the number of C≡C bo ...
... Substantial studies have demonstrated the protective effect of 1,25-Dihydroxyvitamin D3 (1,25(OH)2D3) on intestinal barrier function, but the mechanisms are not fully illustrated. In this study, the effect of 1,25(OH)2D3 on TNF-α induced barrier dysfunction was further investigated in Caco-2 cell monolayers. The barrier function of Caco-2 monolayers was evaluated by measuring trans-epithelial elec ...
... A new series 3-{2-[N′-(1,3-disubstituted-1H-pyrazol-4-yl-methylene)-hydrazino]-thiazol-4-yl}-chromen-2-one (10a–l) was synthesized by a multi-step reaction. All the synthesized compounds were characterized by IR, NMR, and mass spectral studies, followed by elemental analysis. The newly synthesized thiazole compounds were screened for their in vitro antibacterial and antifungal studies against vari ...
... A facile synthesis of 1,3-diiodocalix[4]arene 6 has been achieved by copper-catalyzed iodination of the 1,3-bistriflate ester 2a of p-tert-butylcalix[4]arene. After protection of the hydroxy groups with iodomethane, diiodide 6 is subjected to halogen–lithium exchange with butyllithium, followed by carbonation with CO₂ or formylation with N-formylpiperidine and subsequent deprotection of the hydrox ...
chemical structure; cycloaddition reactions; imines; indolizines
Abstract:
... The thermal 1,3-dipolar cycloadditions of 4-acetoxyallenoates 1 with various dipoles have been reported. When azomethine imines and nitrones are used as the 1,3-dipole partner, the corresponding reactions afford 2,3-dihydropyrazole and 2,3-dihydroisoxazole derivatives, respectively. These reactions might proceed via a thermal 1,3-dipolar cycloaddition and the subsequent elimination of HOAc. In add ...
X-radiation; bromides; chemical structure; cycloaddition reactions; nuclear magnetic resonance spectroscopy; organic compounds
Abstract:
... 1,3-Dipolar cycloaddition reaction of sydnone-N-ylides, as model bis(1,3-dipoles), with acetylenic dipolarophiles in 1,2-epoxybutane under reflux gave exclusively pyrroloazines containing a sydnone moiety that resulted by preferred reaction of the N-ylide 1,3-dipole with the acetylenic dipolarophiles. The assembled sydnone-ylide hybrid structures were generated in situ from N-heteroaromatic bromid ...
chemical reactions; chemical structure; heterocyclic compounds
Abstract:
... A series of 1,2-diaza-1,3-butadienes with terminal S,N-acetal function were obtained and reacted with N-methyl- and N-phenylmaleimides. As a result of the 1,3-dipolar cycloaddition, a range of new functionalized nonaromatic heterocyclic compounds including: octahydro-1H-pyrrolo[3,4-a]indolizine, octahydropyrrolo[3′,4′:3,4]pyrrolo[1,2-a]azepine, hexahydropyrrolo[3′,4′:3,4]pyrrolo[2,1-c][1,4]oxazine ...
... Organogels used as shape-stable phase change materials were prepared by impregnating a low molecular mass organogelator into organic phase change materials. 1,3:2,4-di-(3,4-dimethyl)benzylidene sorbitol (DMDBS) was used as the supporting material and n-octadecane, ethyl palmitate, 1-octadecanol and 1-tetradecanol were used as the phase change materials. The thermal properties, such as phase change ...
amino acids; carbonyl compounds; chemical reactions; chemical structure; esters; ketones; nitrogen
Abstract:
... A novel difunctionalization reaction is described. It uses N-trifluoromethylthio-4-nitrophthalimide as the reagent, which serves as both the nitrogen and SCF₃ sources. In the presence of DABCO (1,4-diazabicyclo[2.2.2]octane), the nitrogen and SCF₃ groups can be incorporated into α,β-unsaturated carbonyl compounds easily and give versatile β-amino ketones and esters in good yields. This difunctiona ...
... In this Letter, a chiral guanidine-catalyzed 1,4-addition reaction of 5H-oxazol-4-ones to vinyl ketones is described. The 1,4-addition reaction proceeded with a high enantioselectivity using 5H-oxazol-4-ones, substituted with a 3-chloro-5-methylphenyl group, as pronucleophiles and a newly developed chiral guanidine as a catalyst. The optimized reaction conditions were also effective in achieving e ...
... Two 1,8-naphthyridine-based N,O-chelated boron complexes (1 and 2) were designed as novel phosphate ion (Pi) probes, which are based on a methoxy oxalyl group reaction site. These two probes showed high selectivity for Pi detection without interference from ATP, PPi, or other anions. Dramatic color changes from colorless to light yellow were observed by addition of Pi to solutions of 1 and 2 in DM ...
... We utilized the potential applications of 1,8-naphthyridine-based sensors for the detection of various nitroaromatics such as picric acid (PA), 3-nitrophenol (NP), 2,4-dinitrotoluene (DNT), 1,3-dinitrobenzene (DNB), 4-nitrotoluene (NT), nitrobenzene (NB) and nitromethane (NM). Among the various nitroaromatic analogues, nap-OH (1) and nap-Cl (2) sense picric acid (PA) much more efficiently and with ...
... Hyperuralones C–H (1–6), six new 1,9-seco-bicyclic polyprenylated acylphloroglucinols (1,9-seco-BPAPs) derived from the normal polyprenylated acylphloroglucinols with a bicyclo[3.3.1]nonane-2,4,9-trione core, together with six known analogues, were isolated from the aerial parts of Hypericum uralum. The structures of 1–6 were elucidated on the basis of the interpretation of NMR and MS spectroscopi ...
... The systematic synthesis of five 1-, 3-, 6-, and 8-tetrasubstituted asymmetric pyrenes with electron donor and acceptor moieties is presented, together with an examination of their photophysical properties. Pyrene derivative PA1, containing one formyl and three piperidyl groups, showed bright solvatochromic fluorescence from green (λₑₘ = 557 nm, ΦFL = 0.94 in hexane) to red (λₑₘ = 648 nm, ΦFL = 0. ...
Adhikari Snehunsu; Chitrini Ghosal; Mamta Kandwal; Pramod K. Yadav; B. Satheesha Nayak; K. Raghavendra Rao; Shobha U. Kamath; Pabitra Sahoo; K.K. Srinivasan; Sareesh Naduvil Narayanan; Shiva Kumar; Alex Joseph
... Marsilea quadrifolia Linn. (MQ) has been used for insomnia and epileptic disorders in traditional Indian medicine. The present study is to isolate the active component responsible for antiepileptic property of MQ by evaluating its ability to minimize the reactive oxidative damage in brain due to chronic epilepsy in rat.1-Triacontanol cerotate (1TAC) was isolated after chromatography on a silica ge ...
... The search for safe, effective and affordable therapeutics against non-small cell lung cancer (NSCLC) and other lung cancers is important. Here we explored the potential effect of 1-o-acetylbritannilactone (ABL), a novel extract from Inula britannica-F, on angiogenesis and lung cancer cell growth. We demonstrated that ABL dose-dependently inhibited vascular endothelial growth factor (VEGF)-induced ...
... Estuarine systems are among the most impacted ecosystems due to anthropogenic contaminants; however, they present unique challenges to toxicity testing with regard to varying water quality parameters. The euryhaline amphipod species, Hyalella azteca, is widely used in toxicity testing and well suited for testing estuarine water samples. Nevertheless, the influence of relevant water quality paramet ...