Retarding oxidation of copper nanoparticles without electrical isolation and the size dependence of work function

Copper nanoparticles (CuNPs) are attractive as a low-cost alternative to their gold and silver analogues for numerous applications, although their potential has hardly been explored due to their higher susceptibility to oxidation in air. Here we show the unexpected findings of an investigation into the correlation between the air-stability of CuNPs and the structure of the thiolate capping ligand: Of the 8 different ligands screened, those with the shortest alkyl chain, -(CH2)2- , and a hydrophilic carboxylic acid end group are found to be the most effective at retarding oxidation in air. We also show that CuNPs are not etched by thiol solutions as previously reported, and address the important fundamental question of how the work function of small supported metal particles scales with particle size. Together these findings set the stage for greater utility of CuNPs for emerging electronic applications

Dietary restriction, caloric value and the accumulation of hepatic fat

<p>Abstract</p> <p>Background</p> <p>Studies using laboratory animals under what are considered to be "standard" conditions normally offer unrestricted amounts of food to the animals, which can lead to metabolic disorders. Moreover, standard diets have different compositions.</p> <p>Aim</p> <p>Therefore, the aim of the present study was to assess the effects of two non-isocaloric diets (commercial Purina^®and AIN-93M), which are considered standard diets, on the accumulation of fat in the liver of rats when offered ad libitum or in a restricted amount.</p> <p>Methods</p> <p>Thus, 40 Wistar rats (90 days old) were separated into 4 groups according to the amount of food offered (ad libitum or dietary restriction) and the type of diet (commercial diet, 3,028.0 kcal/g or AIN-93M, 3,802.7 kcal/g): animals fed the commercial Purina^®diet ad libitum (AP), animals fed restricted amounts of the commercial Purina^®diet (RP), animals fed the AIN-93M diet ad libitum (AD), and animals fed restricted amounts of the AIN-93M diet (RD). Dietary restriction consisted of pair-feeding the RP and RD groups with 60% of the total food consumed by the corresponding ad libitum groups.</p> <p>Results</p> <p>Because of its higher carbohydrate and calorie content, AIN-93M was found to accelerate weight gain, reduce glucose tolerance and peripheral insulin sensitivity, and increase the amount of fat in the liver when compared to the commercial diet. Conversely, a 40% dietary restriction assisted in weight loss without causing malnutrition, contributing to an improved glucose tolerance and higher levels of HDL cholesterol.</p> <p>Conclusion</p> <p>Therefore, differences in the amount of carbohydrates and calories provided by the diet can lead to important metabolic disorders, such as impaired tolerance and accumulation of hepatic fat, and dietary restriction improves serum and tissue lipid profiles in laboratory animals.</p

Designing a functional rice muffin formulated with prebiotic oligosaccharides and sugar reduction

Innovation of pastry products towards higher nutritional and commercial value remains a challenge to the growing field of healthy food. In this study, the prebiotic supplementation and sugar reduction were explored in a widely consumed pastry product with a low level of innovation. The prebiotic potential of commercial agave inulin and galacto-oligosaccharides (GOS) was evaluated and compared by an in vitro model using human fecal inocula. Rice muffins containing 100% of sugar or 75% of sugar supplemented with 0.8% GOS were produced and compared with commercial rice muffins regarding their physical and textural properties. GOS fermentation led to the highest production of lactate and short-chain fatty acids, besides the most significant reduction of the final pH value and of the ammonia and methane production. Inulin presented a higher selectivity towards Lactobacillaceae (51 ± 1% of all), while GOS are more efficient to stimulate Bifidobacteriaceae growth (65 ± 7% of all).This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and BioTecNorte operation (NORTE-01-0145-FEDER000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte; COMPETE 2020 (POCI-01-0145-FEDER-006684), FoSynBio (POCI-01-0145-FEDER-029549) and NewFood (NORTE-01-0246-FEDER000043). CA and BBC acknowledge their grants (UMINHO/BPD/4/2019 and SFRH/BD/132324/2017) from FCT. RM acknowledges the financial support to the Xunta de Galicia and FEDER by the project (EDD431B 2019/01).info:eu-repo/semantics/publishedVersio

Evaluation of the antioxidant activity of cis/trans-N-phenyl-1,4,4a,5,8,8a-hexahydro-3, 1-benzoxazin-2-imines

The growing interest in the chemistry of unsaturated ring-fused 1,3-heterocycles, in this particular case 1,3-oxazines, arise in part from their versatile pharmacological applications. In the present article, the evaluation of the in vitro and ex vivo antioxidant activity of two cyclohexene-fused oxazines is discussed. The in vitro antioxidant activity was evaluated by trapping the ABTS and hydroxyl radicals as well as the inhibition of the enzyme acetyl-cholinesterase and hemolysis of erythrocytes by 2,2’-Azobis(2-amidinopropane) dihydrochloride (AAPH). The results suggest that both unsaturated 1,3-oxazines are auspicious sources of biologically active compounds with good antioxidant properties. In addition, a comprehensive analysis of the interaction between these heterocycles with 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radicals, as well as the measurements of redox potential, provided evidence for a mechanism of antioxidant activity that takes place through electron transfer (ET) processes.Fil: Firpo, Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Ramirez, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Faillace, Martín Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: de Brito, Maria Dos R. Mendes. Universidade Federal Do Piaui.; BrasilFil: Silva, Ana P. S. Correia Lima E.. Universidade Federal Do Piaui.; BrasilFil: Costa, Jessica Pereira. Universidade Federal Do Piaui.; BrasilFil: Rodríguez, Marcela C.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Argüello, Gustavo Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Szakonyi, Zsolt. Institute Of Pharmaceutical Chemistry Albert Szent-györ; HungríaFil: Fülöp, Ferenc. Institute Of Pharmaceutical Chemistry Albert Szent-györ; HungríaFil: Peláez, Walter José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentin

Safeguarding human–wildlife cooperation

Human–wildlife cooperation occurs when humans and free-living wild animals actively coordinate their behavior to achieve a mutually beneficial outcome. These interactions provide important benefits to both the human and wildlife communities involved, have wider impacts on the local ecosystem, and represent a unique intersection of human and animal cultures. The remaining active forms are human–honeyguide and human–dolphin cooperation, but these are at risk of joining several inactive forms (including human–wolf and human–orca cooperation). Human–wildlife cooperation faces a unique set of conservation challenges, as it requires multiple components—a motivated human and wildlife partner, a suitable environment, and compatible interspecies knowledge—which face threats from ecological and cultural changes. To safeguard human–wildlife cooperation, we recommend: (i) establishing ethically sound conservation strategies together with the participating human communities; (ii) conserving opportunities for human and wildlife participation; (iii) protecting suitable environments; (iv) facilitating cultural transmission of traditional knowledge; (v) accessibly archiving Indigenous and scientific knowledge; and (vi) conducting long-term empirical studies to better understand these interactions and identify threats. Tailored safeguarding plans are therefore necessary to protect these diverse and irreplaceable interactions. Broadly, our review highlights that efforts to conserve biological and cultural diversity should carefully consider interactions between human and animal cultures. Please see AfricanHoneyguides.com/abstract-translations for Kiswahili and Portuguese translations of the abstract

Safeguarding human–wildlife cooperation

Human–wildlife cooperation occurs when humans and free-living wild animals actively coordinate their behavior to achieve a mutually beneficial outcome. These interactions provide important benefits to both the human and wildlife communities involved, have wider impacts on the local ecosystem, and represent a unique intersection of human and animal cultures. The remaining active forms are human–honeyguide and human–dolphin cooperation, but these are at risk of joining several inactive forms (including human–wolf and human–orca cooperation). Human–wildlife cooperation faces a unique set of conservation challenges, as it requires multiple components—a motivated human and wildlife partner, a suitable environment, and compatible interspecies knowledge—which face threats from ecological and cultural changes. To safeguard human–wildlife cooperation, we recommend: (i) establishing ethically sound conservation strategies together with the participating human communities; (ii) conserving opportunities for human and wildlife participation; (iii) protecting suitable environments; (iv) facilitating cultural transmission of traditional knowledge; (v) accessibly archiving Indigenous and scientific knowledge; and (vi) conducting long-term empirical studies to better understand these interactions and identify threats. Tailored safeguarding plans are therefore necessary to protect these diverse and irreplaceable interactions. Broadly, our review highlights that efforts to conserve biological and cultural diversity should carefully consider interactions between human and animal cultures

Need satisfaction in intergroup contact:A multinational study of pathways toward social change

none43siFinanziamenti esterni a vari co-autoriWhat role does intergroup contact play in promoting support for social change toward greater social equality? Drawing on the needs-based model of reconciliation, we theorized that when inequality between groups is perceived as illegitimate, disadvantaged group members will experience a need for empowerment and advantaged group members a need for acceptance. When intergroup contact satisfies each group's needs, it should result in more mutual support for social change. Using four sets of survey data collected through the Zurich Intergroup Project in 23 countries, we tested several preregistered predictions, derived from the above reasoning, across a large variety of operationalizations. Two studies of disadvantaged groups (Ns = 689 ethnic minority members in Study 1 and 3,382 sexual/gender minorities in Study 2) support the hypothesis that, after accounting for the effects of intergroup contact and perceived illegitimacy, satisfying the need for empowerment (but not acceptance) during contact is positively related to support for social change. Two studies with advantaged groups (Ns = 2,937 ethnic majority members in Study 3 and 4,203 cis-heterosexual individuals in Study 4) showed that, after accounting for illegitimacy and intergroup contact, satisfying the need for acceptance (but also empowerment) is positively related to support for social change. Overall, findings suggest that intergroup contact is compatible with efforts to promote social change when group-specific needs are met. Thus, to encourage support for social change among both disadvantaged and advantaged group members, it is essential that, besides promoting mutual acceptance, intergroup contact interventions also give voice to and empower members of disadvantaged groups.mixedHässler, Tabea; Ullrich, Johannes; Sebben, Simone; Shnabel, Nurit; Bernardino, Michelle; Valdenegro, Daniel; Van Laar, Colette; González, Roberto; Visintin, Emilio Paolo; Tropp, Linda R; Ditlmann, Ruth K; Abrams, Dominic; Aydin, Anna Lisa; Pereira, Adrienne; Selvanathan, Hema Preya; von Zimmermann, Jorina; Lantos, Nóra Anna; Sainz, Mario; Glenz, Andreas; Kende, Anna; Oberpfalzerová, Hana; Bilewicz, Michal; Branković, Marija; Noor, Masi; Pasek, Michael H; Wright, Stephen C; Žeželj, Iris; Kuzawinska, Olga; Maloku, Edona; Otten, Sabine; Gul, Pelin; Bareket, Orly; Corkalo Biruski, Dinka; Mugnol-Ugarte, Luiza; Osin, Evgeny; Baiocco, Roberto; Cook, Jonathan E; Dawood, Maneeza; Droogendyk, Lisa; Loyo, Angélica Herrera; Jelić, Margareta; Kelmendi, Kaltrina; Pistella, JessicaHässler, Tabea; Ullrich, Johannes; Sebben, Simone; Shnabel, Nurit; Bernardino, Michelle; Valdenegro, Daniel; Van Laar, Colette; González, Roberto; Visintin, Emilio Paolo; Tropp, Linda R; Ditlmann, Ruth K; Abrams, Dominic; Aydin, Anna Lisa; Pereira, Adrienne; Selvanathan, Hema Preya; von Zimmermann, Jorina; Lantos, Nóra Anna; Sainz, Mario; Glenz, Andreas; Kende, Anna; Oberpfalzerová, Hana; Bilewicz, Michal; Branković, Marija; Noor, Masi; Pasek, Michael H; Wright, Stephen C; Žeželj, Iris; Kuzawinska, Olga; Maloku, Edona; Otten, Sabine; Gul, Pelin; Bareket, Orly; Corkalo Biruski, Dinka; Mugnol-Ugarte, Luiza; Osin, Evgeny; Baiocco, Roberto; Cook, Jonathan E; Dawood, Maneeza; Droogendyk, Lisa; Loyo, Angélica Herrera; Jelić, Margareta; Kelmendi, Kaltrina; Pistella, Jessic

A large-scale test of the link between intergroup contact and support for social change

Guided by the early findings of social scientists, practitioners have long advocated for greater contact between groups to reduce prejudice and increase social cohesion. Recent work, however, suggests that intergroup contact can undermine support for social change towards greater equality, especially among disadvantaged group members. Using a large and heterogeneous dataset (12,997 individuals from 69 countries), we demonstrate that intergroup contact and support for social change towards greater equality are positively associated among members of advantaged groups (ethnic majorities and cis-heterosexuals) but negatively associated among disadvantaged groups (ethnic minorities and sexual and gender minorities). Specification-curve analysis revealed important variation in the size—and at times, direction—of correlations, depending on how contact and support for social change were measured. This allowed us to identify one type of support for change—willingness to work in solidarity— that is positively associated with intergroup contact among both advantaged and disadvantaged group members