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Herbicides play a vital role in agriculture, contributing to increased crop productivity by minimizing weed growth, but their low degradability presents a threat to the environment and human health. Allelochemicals, such as DIBOA (2,4-dihydroxy-(2H)-1,4-benzoxazin-3(4 H)-one), are secondary metabolites released by certain plants that affect the survival or growth of other organisms. Although these metabolites have an attractive potential for use as herbicides, their low natural production is a critical hurdle. Previously, the synthesis of the biologically active analog D-DIBOA (4-hydroxy-(2H)-1,4-benzoxazin-3(4H)-one) was achieved, using an engineered E. coli strain as a whole-cell biocatalyst, capable of transforming a precursor compound into D-DIBOA and exporting it into the culture medium, although it cannot be directly applied to crops. Here a chromatographic method to purify D-DIBOA from this cell culture medium without producing organic solvent wastes is described. The purification of D-DIBOA from a filtered culture medium to the pure compound could also be automated. Biological tests with the purified compound on weed models showed that it has virtually the same activity than the chemically synthesized D-DIBOA.

Eight different compounds inspired by benzoxazinones were synthesized in one simple step with easy purification. These compounds have a sulfur atom instead of the oxygen atom present in benzoxazinones. Furthermore, a new derivative obtained by a Rutkauskas–Beresnevicius reaction was synthesized. These compounds were evaluated in vitro to assess their phytotoxicity in plant cells by the elongation of wheat coleoptiles. The novel compounds showed higher inhibition than benzoxazinones and the positive control, especially at higher concentrations (1000 and 300 μM). Benzoxazinones have been described as histidine deacetylase inhibitors and we therefore evaluated the effect of 1.4-benzothiazinones and 1.4-benzoxathianones against HDA6, one of the most important enzymes of the family, in silico by molecular docking and molecular dynamics. In vitro studies against Echinochloa crus-galli, Lolium rigidum and Portulaca oleracea weeds gave interesting results against the growth of the roots for both monocots and dicots. Specifically, the inhibition was more pronounced against dicots, as in the case of common purslane, whose inhibition at a concentration of 1000 μM was similar to that of the classical herbicide employed as a positive control. Higher inhibition was obtained when an aliphatic group was present in the C2 position of 1.4-benzothiazinones.

Phase transition temperatures of three ionic liquids (ILs) with ammonium cations of different alkyl chain length and nitrate common anion were determined in this paper by differential scanning calorimetry. Thermal stability of these ILs in air and nitrogen atmosphere and the maximum operation temperatures of the compounds were also studied using a thermogravimetric analyser. Furthermore, thermophysical properties as density, viscosity, thermal conductivity, and heat capacity against temperature of these pure ionic liquids were determined and compared with the corresponding values for water saturated samples. For this purpose, different techniques were employed: for density and viscosity a rotational automated viscodensimeter; for thermal conductivity measurements a thermal conductimeter that follows the transient hot-wire method; and for heat capacity measurements a microdifferential scanning calorimeter. Different behaviours were observed depending on the analysed thermophysical properties. In case of dried samples, density and thermal conductivity decrease with alkyl chain; for saturated samples, same tendency is observed for density but is the opposite in case of thermal conductivity. Isobaric specific heat and viscosity increase with alkyl chain length in case of dried samples; for saturated samples same tendency is observed for the viscosity, whereas the tendency is the contrary in case of isobaric specific heat.

This article studies the feasibility of using low-cost materials, techniques, and tools to manufacture a 1/100-scale model of a VLCC. For this purpose, three main aspects were considered to reduce the production costs: 1) the bypass to the fabrication of a mold, by building directly the final hull with mid-density fiber wood; 2) the use of a 3 degrees of freedom computer numerical control (CNC) milling machine to cut and shape the pieces of the hull, which can be easily rented at affordable prices; 3) the automation as much as possible of the process to avoid contracting highly skilled personnel to do manual tasks, which would increase substantially the fabrication costs. The article is based on the practical case study of the fabrication of the KVLCC2 (KRISO Very Large Crude Carrier 2) scale model, which is used to describe the digital models, the milling process, and the finishing work. At the end, the validation of the model is done by comparing the final physical hull surface with the original digital one. This study is mainly directed to small maritime research centers and/or universities, which are interested in performing maneuvering experiments with homemade ship scale models.

Funding: This work was supported by the Portuguese National Funds through FCT—Fundação para a Ciência e a Tecnologia, I.P., within: I&D units grants CFCUL—Centro de Filosofia das Ciências da Universidade de Lisboa (grant numbers FCT I.P.: UIDB/00678/2020 e UIDP/00678/2) and cE3c—Centre for Ecology, Evolution and Environmental Changes (grant number FCT I.P.: UID/BIA/00329/2013), and within Inês Órfão’s PhD grant (grant number SFRH/BD/90686/2012), and the Post-Doctoral research grants of Miguel Barbosa (grant number SFRH/BPD/82259/2011) and Susana AM Varela (grant number SFRH/BPD/66042/2009). Inês Órfão received financial support from ARDITI (M1420-09-5369-FSE-000002) and Miguel Barbosa received financial support from CESAM (UIDP/50017/2020þUIDB/50017/2020). This work was also supported by the European Research Council (ERC) within the project BioTIME (ERC grant number 250189). Background Evidence of male-male courtship display is widespread across the animal kingdom. Yet, its function and evolutionary origin remain unclear. Here, we hypothesise that male-male courtship display evolved in response to selection pressure exerted by intrasexual competition during male-female courtship interactions. Intrasexual competition can be caused by bystander male pressure through eavesdropping and exploiting on displayer male’s courtship interactions with females. This bystander pressure can lead to an audience effect by the displayer, who will change their courtship behaviour in the presence of bystanders and display directly towards them, even in the absence of females, as an intimidation strategy. In species where this selection pressure has taken place, we predict that the male courtship display will have a dual function: attract females and deter competitors. Therefore, we expected to find more evidence of bystander-related behaviours in species for which male-male courtship display is linked to intrasexual competition compared to species for which other explanatory hypotheses are more plausible (e.g., mistaken identity or courtship practice). Methodology We conducted two systematic reviews to test this hypothesis. First, we conducted a search for studies of species with courtship display between males and of the hypotheses provided to explain this behaviour. Our goal was to identify the species with male-male courtship display and evidence of intrasexual competition. Second, among the species with male-male courtship display, we searched for evidence of bystander-related behaviours, i.e., articles referring to eavesdropping, exploitation, and audience effect during male-female courtship interactions. Our goal was to test whether species with intrasexual competition are also more likely to show bystander-related behaviours. Results Although most studies reporting male courtship display towards other males do not suggest any explanatory hypothesis for this behaviour, the intrasexual competition hypothesis was largely mentioned and supported by some studies reviewed. Additionally, there is more evidence of eavesdropping and of all three bystander-related behaviours combined in species for which the intrasexual competition hypothesis was suggested. Conclusions Overall, our review supports the hypothesis that intrasexual competition can play a key role in male courtship display evolution, namely that male-male courtship display may have evolved as a secondary function of male-female courtship interactions via bystander male pressure. However, our review also shows that despite the increasing interest in same-sex sexual behaviours, and male-male courtship display in particular, most studies were found to be merely descriptive, and the hypotheses they suggested to explain courtship display between males mostly speculative. This highlights an important gap in the literature. To clarify both the evolution and the function of male-male courtship display, this behaviour needs to be empirically studied more often. Our review can help advancing this research area, as it makes the 20 species with male-male courtship display for which the intrasexual competition hypothesis was suggested excellent candidates for empirical research. Publisher PDF

Aqueous solubility and stability often limit the application of aminophenoxazinones and their sulfur mimics as promising agrochemicals in a sustainable agriculture inspired by allelopathy. This paper presents a solution to the problem using host-guest complexation with cucurbiturils (

The purpose of this study was to compare the composition and stability of bacteria and fungi communities during the propagation of sourdoughs prepared with organic or conventional whole wheat (Triticum aestivum) flours from South Brazil. Sourdoughs were prepared and samples were collected during different fermentation times (0 to 216 h). Total DNA of sourdough samples were extracted and the 16S rRNA gene and Internal Transcribed Spacer region were sequenced by MiSeq-Illumina. A total of 43 and 56 OTUs were identified and defined as core taxa in the bacterial and fungal communities, respectively. The analysis revealed increases in the relative abundances of the lactic acid (Pediococcus pentosaceus, Weissella hellenica and Limosilactobacillus pontis) and acetic acid bacteria (Gluconobacter frateurii and Acetobacter tropicalis) during the sourdough propagation. The filaments fungi, Alternaria tenuissima, Fusarium culmorum, Fusarium petersiae and Microdochium seminicola remained more stable in organic than conventional during propagation cycles. After 216 h of fermentation, both sourdoughs were dominated by acid- and salt-tolerant yeast Issatchenkia orientalis (syn Pichia kudriavzevii, and Candida glycerinogenes). In conclusion, there were no significant differences in microbial communities among the sourdough samples. This study revealed that both flours contain autochthonous LAB, AAB, and yeasts with biotechnological applications in sourdough bread-making.

Research article, Zooplankton grazing onphytoplankton promotes the release of particulate and dissolved organic matter (DOM) into the water column and therefore plays a key role in organic matter cycling in aquatic systems. Prokaryotes are the main DOM consumers in the ocean by actively remineralizing and transforming it, contributing to its molecular diversification. To explore the molecular composition of zooplankton-derived DOM and its bioavailability to natural prokaryotic communities, the DOM generated by a mixed zooplankton community in the coastal Atlantic off Spain was used as substrate for a natural prokaryotic community and monitored over a ~ 5-d incubation experiment. The molecular composition of solid-phase extracted DOM was characterized via Fourier-transform ion cyclotron resonance mass spectrometry. After ~ 4 d in the zooplankton-derived DOM amended incubation, the prokaryotic community demonstrated a 17-fold exponential increase in cell number. The prokaryotic growth resulted in a reduction in bulk dissolved organic carbon concentration and the zooplankton-derived DOM was considerably transformed at molecular and bulk elemental levels over the incubation period. The C : N ratio (calculated from the obtained molecular formulae) increased while the functional diversity decreased over the incubation time. In addition, molecular indices pointed to a reduced bioavailability of DOM at the end of the experiment. These findings show that zooplankton excreta are a source of labile organic matter that is quickly metabolized by the prokaryotic community. Therefore, a fraction of carbon is shunted from transfer to secondary consumers similarly to the viral shunt, suggesting that the zooplankton–prokaryotic interactions play an important role in the ocean's carbon cycle., IEO, XUNTA DE GALICIA (INGO7A 2018/2), DFG (CO 2218/2-1 and TRR51)

The closest environment of Al3+ cations was analyzed in detail in solutions of aluminum nitrate in the prototypical protic ionic liquid ethyl ammonium nitrate (EAN) using 1 H and 14 N nuclear magnetic resonance (NMR) spectra. For Al (NO3 )3 -EAN mixtures with different water content, a quantitative analysis of the integral intensities of the 1 H and 14 N signals was carried out and the composition of the first solvation shell of the aluminum cation was refined.

[Abstract] In this work, we deepen in the characterization of two protic ionic liquids (PILs), ethylammonium nitrate (EAN) and propylammonium nitrate (PAN). With this aim, we determined the influence of inorganic nitrate salts addition on their physical properties and their electrochemical potential window (EPW). Thus, experimental measurements of electrical conductivity, density, viscosity, refractive index and surface tension of mixtures of {EAN or PAN + LiNO3, Ca(NO3)2, Mg(NO3)2 or Al(NO3)3} at a temperature range between 5 and 95 °C are presented first, except for the last two properties which were measured at 25 °C. In the second part, the corresponding EPWs were determined at 25 °C by linear sweep voltammetry using three different electrochemical cells. Effect of the salt addition was associated mainly with the metal cation characteristics, so, generally, LiNO3 showed the lower influence, followed by Ca(NO3)2, Mg(NO3)2 or Al(NO3)3. The results obtained for the EAN + LiNO3 mixtures, along with those from a previous work, allowed us to develop novel predictive equations for most of the presented physical properties as functions of the lithium salt concentration, the temperature and the water content. Electrochemical results showed that a general order of EPW can be established for both PILs, although exceptions related to measurement conditions and the properties of the mixtures were found. This research was funded by the Spanish Ministry of Economy, Industry and Competitiveness, grant numbers MAT2017-89239-C2-1-P and MAT2017-89239-C2-2-P. D. Ausín thanks the funding support of Fundación Segundo Gil Dávila

Introduction Although alcohol cessation is the only effective treatment for alcohol-related liver disease, few data exist concerning its influence on the risk of hepatocellular carcinoma (HCC). We aimed to evaluate the effect of alcohol abstinence on the incidence of HCC in patients with alcohol-related cirrhosis. Methods We studied 727 patients with alcohol-related cirrhosis (247 with compensated disease and 480 with previous decompensation) who were included in a surveillance program for the early detection of HCC and prospectively followed. Baseline clinical and biological parameters and alcohol consumption during follow-up were recorded. Abstinence was defined as the absence of any alcohol use. Results During follow-up (median 54 months), 354 patients (48.7%) remained abstinent and 104 developed HCC (2.3 per 100 person-years). Factors independently associated with the risk of HCC among patients with previous decompensation were age, male gender, and aspartate aminotransferase, whereas abstinence was not linked to a reduced risk (hazard ratio 0.95; 95% confidence interval 0.59-1.52). However, among patients without previous decompensation, prothrombin activity and abstinence were independently associated with the risk of HCC. Abstinent patients had a significant decrease in the risk of developing tumor (hazard ratio 0.35; 95% confidence interval 0.13-0.94). These results did not change after applying a competing risk analysis where death and liver transplantation were considered as competing events. Discussion Alcohol abstinence reduced the risk of HCC in patients with alcohol-related cirrhosis, but only in those without a history of decompensated disease. This finding emphasizes the need for an early diagnosis of alcohol-related liver disease and for implementing strategies leading to an increase in the rate of achieving and maintaining abstinence among this population.

C-17-sesquiterpenoids are a group of natural products that have been recently discovered. These compounds have the peculiarity of lacking the alpha,beta-methylene butyrolactone system, which is known to be quite relevant for many of the biological activities reported for sesquiterpene lactones. Unfortunately, the biological interest of C-17-sesquiterpenoids has not been studied in-depth, mainly due to the poor isolation yields in which they can be obtained from natural sources. Therefore, in order to allow a deeper study of these novel molecules, we have worked out a synthetic pathway that provides C-17-sesquiterpenoids in enough quantities from easily accessible sesquiterpene lactones to enable a more thorough investigation of their bioactivities. With this synthesis method, we have successfully synthesized, for the first time, three natural C-17-sesquiterpenoids, pertyolides A, B, and C, with good overall yields. Furthermore, we have also evaluated their phytotoxicity against etiolated wheat coleoptiles and corroborated that pertyolides B and C present strong phytotoxic activity., This research was supported by the Ministerio de Economia, Industria y Competitividad (MINEICO), Spain, AGL2017-88083-R.

We report the structure and charge transport properties of a novel solid-state proton conductor obtained by acid-base chemistry via proton transfer from 12-tungstophosphoric acid to imidazole. The resulting material (henceforth named Imid3WP) is a solid salt hydrate that, at room temperature, includes four water molecules per structural unit. To our knowledge, this is the first attempt to tune the properties of a heteropolyacid-based solid-state proton conductor by means of a mixture of water and imidazole, interpolating between water-based and ionic liquid-based proton conductors of high thermal and electrochemical stability. The proton conductivity of Imid3WP·4H2O measured at truly anhydrous conditions reads 0.8 × 10-6 S cm-1 at 322 K, which is higher than the conductivity reported for any other related salt hydrate, despite the lower hydration. In the pseudoanhydrous state, that is, for Imid3WP·2H2O, the proton conductivity is still remarkable and, judging from the low activation energy (Ea = 0.26 eV), attributed to structural diffusion of protons. From complementary X-ray diffraction data, vibrational spectroscopy, and solid-state NMR experiments, the local structure of this salt hydrate was resolved, with imidazolium cations preferably orienting flat on the surface of the tungstophosphate anions, thus achieving a densely packed solid material, and water molecules of hydration that establish extremely strong hydrogen bonds. Computational results confirm these structural details and also evidence that the path of lowest energy for the proton transfer involves primarily imidazole and water molecules, while the proximate Keggin anion contributes with reducing the energy barrier for this particular pathway.

In the work described here, a number of sesquiterpenes and benzoxazinoids from natural sources, along with their easily accessible derivatives, were evaluated against the main protease, RNA replicase and spike glycoprotein of SARS-CoV-2 by molecular docking. These natural products and their derivatives have previously shown remarkable antiviral activities. The most relevant compounds were the 4-fluoro derivatives of santamarine, reynosin and 2-amino-3

The external surface microornament of the glass scallops Catillopecten natalyae and malyutinae is made by calcitic spiny projections consisting of a stem that later divides into three equally spaced and inclined branches (here called aerials). C. natalyae contains larger and smaller aerials, whereas C. malyutinae only secreted aerials of the second type. A remarkable feature is that aerials within each type are fairly similar in size and shape and highly co-oriented, thus constituting a most sophisticated microornament. We demonstrate that aerials are single crystals whose morphology is strongly controlled by the crystallography, with the stem being parallel to the c-axis of calcite, and the branches extending along the edges of the {104} calcite rhombohedron. They grow epitaxially onto the foliated prisms of the outer shell layer. The co-orientation of the prisms explains that of the aerials. We have developed a model in which every aerial grows within a periostracal pouch. When this pouch reaches the growth margin, the mantle initiates the production of the aerial. Nevertheless, later growth of the aerial is remote, i.e. far from the contact with the mantle. We show how such an extremely sophisticated microornament has a morphology and co-orientation which are determined by crystal growth., Instituto de Salud Carlos III Spanish Government CGL2017-85118-P PID2020-116660GB-I00, Unidad Cientifica de Excelencia of the University of Granada UCE-PP2016-05, Junta de Andalucia RNM363, Ministry of Science, ICT & Future Planning, Republic of Korea 13.1902.21.001 075-15-2020-796

Natural products are a promising source for the development of new pesticides with alternative mechanisms of action. In this study, we evaluated the phytotoxic and antifungal activity of a novel family of natural CMany tested compounds exhibited a strong phytotoxic activity. Lappalone and pertyolide B were the most potent molecules from the tested group. Lappalone displayed a strong inhibition profile against selected weed species, reaching a half-maximal inhibitory concentration (ICThe bioassays revealed that frequently the presence of the α-methylene-γ-butyrolactone system is not essential for the bioactivities of sesquiterpene lactones, and suggest that C