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1.
World J Microbiol Biotechnol ; 39(9): 254, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37462834

RESUMO

Spent coffee grounds (SCG) are wastes generated in high amounts worldwide. Their composition makes them a promising feedstock for biotechnological processes. Here we show that the production of the biosurfactant surfactin by submerged culture of a Bacillus subtilis strain growing on SCG is possible, reaching concentrations up to 8.8 mg/L when using SCG at 8.3 g/L in the medium. In addition, we report a synergy between the production of surfactin and the recovery of melanoidins, an added-value compound already present in SCG. More specifically, the concentration of melanoidins in the culture medium increased between 2.1 and 2.5 times thanks to the presence of the B. subtilis in the culture. Furthermore, we have observed a strong interaction between surfactin and melanoidin aggregates through dynamic light scattering measurements, and that both of them can be co-purified with an acid precipitation. We have also characterized the interfacial and antioxidant properties of the cell-free supernatant and surfactin extract, as well as the distribution of the congeners of the biosurfactant. Altogether, this work describes a promising approach to obtain biosurfactants and antioxidant molecules in a single operation, which can be used to design several new formulations of interest for bioremediation, amendment of soils, food and cosmetics.


Assuntos
Antioxidantes , Café , Polímeros , Biotecnologia
2.
J Environ Manage ; 302(Pt B): 114075, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34800772

RESUMO

SCG are a bio-waste generated in great amount worldwide which are attractive as soil amendment for their high content of organic matter and nutritive elements. Nevertheless, several studies have shown that soil application of untreated SCG has detrimental agronomic and environmental effects due to their high degradability and content of noxious compounds (phenols, caffeine, and tannins). However, SCG can be valorised, in the frame of circular economy, by extraction of energy and valuable products (carbohydrates, proteins, bio-oil, bio-diesel) and generation of solid by products (biochar, hydrochar, compost) that can be utilized as soil fertilizers and amendments. Therefore, the aim of this work was the characterization of different solid SCG by-products (as second-generation products) and their assessment as effective organic amendments. The novelty of this study is that for the first time 8 different by-products derived from the same SCG were characterized and comparatively evaluated for their impact on the C and N cycles of soil. SCG was collected and treated to generate 8 different SCG by-products (biochars produced at 270 and 400 °C, hydrochars produced at 160 and 200 °C, vermicompost, defatted SCG and biochars produced from defatted SCG at 270 and 400 °C). SCG and derived by-products were characterized for SEM micromorphology, pH and EC values, and C, N, H, O, volatile matter, fixed C, LOI, carbonates, water soluble C and N, NO3- and NH4+ content. SCG and SCG by-products assessment as organic amendments was performed with an incubation experiment. The residues were added (2.5%) to a moist Mediterranean agricultural soil and the amended soil samples were placed in mesocosms and incubated at 20 °C for 30 days. During incubation, CO2 and N2O emissions were measured every 6 h by means of a gas chromatography automated system for GHG sampling and measurement. The percentage of added C remaining (CR) in the soil was calculated by fitting the cumulative respiration of amended soil to a two-pool model. After 2, 7 and 30 days of incubation, the control and amended soils were sampled and analyzed for their content of extractable organic C, N, NO3- and NH4+ and microbial biomass C and N. Results showed that SCG by-products presented a great variability in their properties. SCG and hydrochars presented higher contents in volatile matter and water soluble C and N, and low content of fixed C, while biochars showed an opposite behaviour. SEM images confirmed the different characteristics of the SCG by-products: the biochar presented a porous structure, honeycomb-like form, due to the loss of the more soluble compounds, while the SCG and hydrochars' pores were filled with amorphous carbonaceous materials. Consequently, soil addition of SCG by-products showed a distinct impact on C and N cycle and microbial biomass content. Addition of SCG and hydrochars generated the highest cumulative CO2-C emissions (2103-2300 µg g-1), the lower amount of CR (86.8-88.6%), increased the soil extractable organic C and microbial biomass C and N and caused N immobilization. On the other hand, the addition of biochars generated lower CO2-C emissions (542-1060 µg g-1), higher amounts of CR (96. 3-99.9%) and lower amounts of extractable compounds and microbial biomass C and N, generating also N immobilization, but to a lesser extent. The addition of vermicompost generated 723 µg g-1 of CO2-C and 98% of CR remaining. However, this by-product did not generate N immobilization being able to act as N fertilizer. None of the residues generated N2O emissions. The different properties of the SCG by-products and their impact on C and N cycle indicated that they can be effectively applied to soil to exert different agronomical and environmental functions.


Assuntos
Compostagem , Solo , Agricultura , Carvão Vegetal , Café , Fertilizantes
3.
J Org Chem ; 86(4): 3344-3355, 2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33533618

RESUMO

We have proven that the biomimetic-like synthesis of cannabinoids from citral and the corresponding phenolic counterpart may well be carried out using water as a solvent. The influence of different additives such as surfactants was also analyzed. Rationalization of the reaction mode and regiochemistry of the processes were provided in terms of "on water" and "in water" reactions. The same reactions were conducted in organic media using Ga(III) salts as catalysts. Worthy of being underlined, an unprecedented formal [2+2+2] process was found to occur between two citral molecules and the corresponding phenolic species in both aqueous and organic environments. Computational studies were performed in order to gain a comprehensive mechanistic and energetic understanding of the different steps of this singular process. Finally, the influence of SDS micelles in the chemical behavior of olivetol and citral was also pursued using PGSE diffusion and NOESY NMR studies. These data permitted to tentatively propose the existence of a mixed micelle between olivetol and SDS assemblies.


Assuntos
Canabinoides , Micelas , Solventes , Tensoativos , Água
4.
Langenbecks Arch Surg ; 406(5): 1581-1589, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33409584

RESUMO

INTRODUCTION: There is still controversy regarding the ideal technique to close the appendicular stump in laparoscopic appendectomy (LA). The objective of this study was to determine the safety and efficiency of the use of an endoloop (EL) and endostapler (ES) in complicated and uncomplicated acute appendicitis. METHODS: Retrospective cohort study of patients undergoing LA from February 2013 to December 2019. Acute uncomplicated and complicated appendicitis were analysed separately, establishing two groups according to the stump closure technique: EL or ES. Seven hundred-nine patients were included (535 uncomplicated and 174 complicated). In uncomplicated appendicitis, an EL was used in 447 of the patients (83.55%) and an ES was used in 88 patients (16.45%). In complicated appendicitis, an EL was used in 85 patients (48.85%) and an ES was used in 89 patients (51.15%). An analysis of effectiveness and a cost analysis of each technique were performed. RESULTS: In uncomplicated appendicitis, we found no differences with respect to global complications, although there were significant differences in the total mean hospital stay (EL group 1.55 (SD 1.48) days; ES group 2.21 (SD 1.69) days; p = 0.046). This meant a savings of 514.12€ per patient using the EL p < 0.001). In complicated appendicitis, the reoperations classified as Clavien-Dindo IIIB in the EL group (6.4%) were greater than in the ES group (0%) (p = 0.012), although the rate of postoperative abscesses (p = 0.788) and the mean volume of abscesses (p = 0.891) were similar. CONCLUSION: The systematic use of an EL could reduce costs in uncomplicated appendicitis, while in complicated cases, both options are valid. Prospective studies with a greater number of patients are needed to observe differences in postoperative complications.


Assuntos
Apendicite , Laparoscopia , Apendicectomia/efeitos adversos , Apendicite/cirurgia , Humanos , Tempo de Internação , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos , Estudos Retrospectivos
5.
Surg Today ; 50(9): 1107-1112, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32700005

RESUMO

Quick implementation of specific protocols and protective measures in a tertiary hospital in Spain allowed for the early diagnosis and optimal management of patients with SARS-CoV-2 infection and proper protection of staff and inpatients. From the COVID-19 outbreak in this country until the time of writing, 14 patients in our hospital underwent surgery with COVID-19, or COVID-19 developed postoperatively. Their postoperative outcomes did not differ from those in our routine clinical practice, with a 0% respiratory failure rate and a 7.14% mortality rate, in contrast with other published series. COVID-19 did not develop in any of the healthcare workers present in the operating room during these procedures or in those who cared for these patients on the ward.


Assuntos
Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Controle de Infecções/organização & administração , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Procedimentos Cirúrgicos Operatórios , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19 , Protocolos Clínicos , Estudos de Coortes , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Feminino , Humanos , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , SARS-CoV-2 , Espanha , Resultado do Tratamento
6.
Biotechnol Bioeng ; 116(4): 846-856, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30450554

RESUMO

Protein A chromatography is an effective capture step to separate Fc-containing biopharmaceuticals from cell culture impurities but is generally not effective for virus removal, which tends to vary among different products. Previous findings have pointed to the differences in feedstocks to protein A, composed of the products and other cell culture-related impurities. To separate the effect of the feedstock components on virus removal, and understand why certain monoclonal antibody (mAb) products have low virus log reduction values (LRVs) across protein A chromatography, we investigated the partitioning of three types of viruses on Eshmuno® A columns. Using pure mAbs, we found that low LRVs were correlated with the presence of the particular mAb product itself, causing altered partitioning patterns. Three virus types were tested, and the trend in partitioning was the same for retrovirus-like particles (RVLPs) expressed in the cell substrate, and its model virus xenotropic murine leukemia virus (XMuLV), whereas slightly different for murine minute virus. These results were extended from previous observation described by Bach and Connell-Crowley (2015) studying XMuLV partitioning on MabSelect SuRe columns, providing further evidence using additional types of viruses and resin. Other product-specific cell culture impurities in harvested cell culture fluid played a lesser role in causing low LRVs. In addition, using high throughput screening (HTS) methods and Eshmuno® A resin plates, we identified excipients with ionic and hydrophobic properties that could potentially alleviate the mAb-induced LRV reduction, indicating that both ionic and hydrophobic interactions were involved. More excipients of such nature or combinations, once optimized, can potentially be used as load and/or wash additives to improve virus removal by protein A. We have demonstrated that HTS is a valuable tool for this type of screening, whether to gain deeper understanding of a mechanism, or to provide guidance during the optimization of protein A process with improved virus removal.


Assuntos
Anticorpos Monoclonais/química , Vírus da Leucemia Murina/isolamento & purificação , Vírus Miúdo do Camundongo/isolamento & purificação , Retroviridae/isolamento & purificação , Proteína Estafilocócica A/química , Animais , Células CHO , Cromatografia de Afinidade/métodos , Cricetulus
7.
Biodegradation ; 28(4): 303-312, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28567707

RESUMO

Recently, anaerobic degradation has become a prevalent alternative for the treatment of wastewater and activated sludge. Consequently, the anaerobic biodegradability of recalcitrant compounds such as some surfactants require a thorough study to avoid their presence in the environment. In this work, the anaerobic biodegradation of amine-oxide-based surfactants, which are toxic to several organisms, was studied by measuring of the biogas production in digested sludge. Three amine-oxide-based surfactants with structural differences in their hydrophobic alkyl chain were tested: Lauramine oxide (AO-R12), Myristamine oxide (AO-R14) and Cocamidopropylamine oxide (AO-cocoamido). Results show that AO-R12 and AO-R14 inhibit biogas production, inhibition percentages were around 90%. AO-cocoamido did not cause inhibition and it was biodegraded until reaching a percentage of 60.8%. Otherwise, we fitted the production of biogas to two kinetic models, to a pseudo first-order model and to a logistic model. Production of biogas during the anaerobic biodegradation of AO-cocoamido was pretty good adjusted to the logistics model. Kinetic parameters were also determined. This modelling is useful to predict their behaviour in wastewater treatment plants and under anaerobic conditions in the environment.


Assuntos
Aminas/química , Óxidos/química , Tensoativos/química , Anaerobiose , Biodegradação Ambiental , Biocombustíveis , Cinética , Propilaminas/química , Esgotos/química , Fatores de Tempo , Águas Residuárias/química
8.
Cir Esp ; 94(7): 404-9, 2016.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-27402179

RESUMO

INTRODUCTION: The aim of this study is to demonstrate our experience at a volunteer surgical program in Cameroon, which is of special interest given to the inability to adopt international treatment guidelines for thyroid surgery in areas of limited resources due to the lack of preoperative testing and to the difficulty to obtain sustitutive hormonal treatment. METHODS: This is a prospective observational study that includes 16 cases of thyroid surgery in Dschang (Cameroon) during June 2015. The patients were previously selected by a local medical team. All patients were black, 15 women and one man, with a mean age of 41 years. The surgical technique used for the removal of unilateral disease was hemithyroidectomy with isthmectomy and bilateral subtotal thyroidectomy for bilateral disease. RESULTS: Five subtotal thyroidectomies, 9hemithyroidectomies and 2isthmectomies were performed. Prethyroid muscles were divided only in one case. We visualized 86% of the parathyroid glands and 84% of the recurrent laryngeal nerves. The main complications observed were one symptomatic cervical haematoma that required reoperation and 2surgical wound infections. There were no clinical episodes of hypocalemia or recurrent nerve lesion. The mean length of stay was 2.3 days. At follow-up, all bilateral thyroidectomies developed high TSH levels. CONCLUSIONS: Thyroid surgery is safe in developing countries adopting protocols and techniques we use in our environment (avoiding total thyroidectomy). Bilateral thyroidectomies should not be performed unless functional studies are available in the follow-up and a thyroid hormone supplement stock guaranteed whenever necessary.


Assuntos
Bócio/cirurgia , Tireoidectomia , Cuidados de Saúde não Remunerados , Adulto , Camarões , Feminino , Humanos , Cooperação Internacional , Masculino , Estudos Prospectivos
10.
Antioxidants (Basel) ; 13(4)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38671913

RESUMO

Spent coffee grounds (SCG) are a type of food waste and are produced in abundance around the world. However, their utilization as a soil organic amendment is challenging due to their phytotoxic effect. In the present work, the impact of agronomic biofortification on Dutch cucumbers was investigated using different chemically modified SCG and analyzing their effects on iron contents, their capacity for releasing antioxidants, and the production of short-chain fatty acids after in vitro digestion-fermentation. The results indicated variations in the iron contents and chemical compositions of cucumbers according to the treatment groups. Functionalized and activated hydrochar from SCG increased Fe levels in cucumbers. Although activated hydrochar obtained at 160 °C and functionalized with Fe showed the highest iron supply per serving, differences in antioxidant capacity and short-chain fatty acid production were observed between the groups. It is concluded that growing conditions and the presence of iron may significantly influence the contribution of these cucumbers to the dietary intake of nutrients and antioxidants, which could have important implications for human health and nutrition.

11.
Foods ; 13(8)2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38672819

RESUMO

Spent coffee grounds (SCGs) are a food waste with a large generation around the world. However, their utilization as a soil organic amendment is difficult due to their phytotoxic effect. In the present work, the impact of agronomic biofortification on Dutch cucumbers was studied by using different chemically modified SCGs, analyzing their effects on Zn content, the release of antioxidant capacity and the production of short-chain fatty acids after in vitro digestion-fermentation. The results indicated variations in the Zn content and chemical composition of cucumbers according to the treatment groups. The functionalized with Zn and activated SCGs were able to increase Zn levels in cucumbers. Meanwhile, the activated hydrochar obtained at 160 °C and the activated and functionalized with Zn SCGs showed the highest Zn supply per serving. Differences in the antioxidant capacity and short-chain fatty acid production were observed between the groups. It is concluded that the growing conditions and the presence of Zn may significantly influence the contribution of these cucumbers to the dietary intake of nutrients and antioxidants, which could have important implications for human health and nutrition.

12.
Zootaxa ; 3616: 345-56, 2013 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-24758815

RESUMO

We describe a new Pristimantis from La Libertad and Rumiloma, Reserva Mazar, Andes of Southeastern Ecuador, at elevations between 2895-3415 m. This species is assigned to the P. orestes group, from whose members it differs by its small body size (adult males ≤ 18.1 mm; adult females ≤ 23.7 mm), usually reticulated ventral pattern, and visible tympanum. The vocalization of the new species consists of a series of calls; each call is composed by a pulsed, non-modulated note in frequency, and with a dominant frequency of 3122-3171 Hz. A molecular phylogeny based on a fragment of the mitochondrial gene 12S shows that the new species is sister to Pristimantis simonbolivari.


Assuntos
Anuros/classificação , Estruturas Animais/anatomia & histologia , Animais , Anuros/anatomia & histologia , Anuros/crescimento & desenvolvimento , Anuros/fisiologia , Tamanho Corporal , Equador , Feminino , Masculino , Filogenia , Vocalização Animal
13.
Zookeys ; 1143: 1-49, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37234281

RESUMO

A molecular phylogeny of the Neotropical snail-eating snakes (tribe Dipsadini Bonaparte, 1838) is presented that includes 60 of the 133 species currently recognized. There is morphological and phylogenetic support for four new species of Sibon Fitzinger, 1826 and one of Dipsas Laurenti, 1768, which are described here based on their unique combination of molecular, meristic, and color pattern characteristics. PlesiodipsasHarvey et al., 2008 is designated as a junior synonym of Dipsas and additional evidence is presented to support the transfer of the genus Geophis Wagler, 1830 to the tribe Dipsadini. Two of the subspecies of S.nebulatus (Linnaeus, 1758) are elevated to full species status. Insight into additional undescribed cryptic diversity within the S.nebulatus species complex is provided. Evidence that supports the existence of an undescribed species previously confused with D.temporalis is provided, as well as the first country record of S.ayerbeorum Vera-Pérez, 2019 in Ecuador with a comment on the ontogenetic variation of the latter. Finally, photographs of Colombian, Ecuadorian, and Panamanian snail-eating snakes are provided.

14.
Zookeys ; 1145: 131-167, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37234698

RESUMO

A new species of Dipsas Laurenti, 1768, from Central Panama is described based on molecular analyses, hemipenial morphology, and external characters. This is the sixth species of Dipsas to be described for the country; the snake has been suspected to exist since 1977 and has not been thoroughly studied until now. Additionally, morphological comparations including scale counts are done with other species within the genus, and the current geographic distribution of Dipsastemporalis (Werner, 1909), the sister species, is updated. Finally, a key to the species of Dipsas currently known from Middle America is presented.


ResumenDescribimos una nueva especies de Dipsas Laurenti, 1768 de la región central de Panamá en base a análisis moleculares, morfología hemipenial y caracteres de morfología externa. Esta es la sexta especie del género Dipsas descrita para el país. Se sospechaba su existencia desde 1977 pero no había sido estudiada exhaustivamente hasta ahora. Adicionalmente, presentamos comparaciones morfológicas (incluyendo lepidosis) con otras especies del género y actualizamos la distribución geográfica de su especie hermana Dipsastemporalis (Werner, 1909). Finalmente, presentamos una clave para las especies de Dipsas distribuidas en Centroamérica.

15.
Sports (Basel) ; 11(10)2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37888517

RESUMO

BACKGROUND: The objective of this study was to investigate the impact of a customized exercise program on electromyographic (EMG) variables during side-cutting maneuvers. METHODS: Fifty-seven physically active volunteers were recruited and randomized into two groups: a control group (CG) and an experimental group (EG). The CG maintained their regular physical activity, while the EG followed an individualized, integrated exercise regimen that included strength, neuromuscular, proprioceptive, eccentric training, and whole-body vibration (WBV) exercises, lasting for 12 weeks. EMG-Root Means Square (RMS) values for the quadriceps (Q) and hamstrings (H) were measured immediately following initial foot contact at 50, 100, 150, and 200 milliseconds. Changes in EMG activity were evaluated before and after a twelve-week intervention, and the effect size (ES, 90% confidence limit [90%CL]) was calculated. RESULTS: The results showed that the EG participants exhibited enhanced co-contraction as measured by the hamstring/quadriceps ratio (H/Q ratio) during both open and cross-cutting side maneuvers after the twelve-week intervention. CONCLUSION: Furthermore, the customized, integrated exercise program that combined strength, neuromuscular, proprioceptive, eccentric training, and WBV exercises were could potentially serve as a beneficial neuromuscular and biomechanical strategy for addressing knee injury risk in non-professional, physically active populations at high risk for such injuries.

16.
Nat Commun ; 14(1): 6191, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37848442

RESUMO

Tropical forest recovery is fundamental to addressing the intertwined climate and biodiversity loss crises. While regenerating trees sequester carbon relatively quickly, the pace of biodiversity recovery remains contentious. Here, we use bioacoustics and metabarcoding to measure forest recovery post-agriculture in a global biodiversity hotspot in Ecuador. We show that the community composition, and not species richness, of vocalizing vertebrates identified by experts reflects the restoration gradient. Two automated measures - an acoustic index model and a bird community composition derived from an independently developed Convolutional Neural Network - correlated well with restoration (adj-R² = 0.62 and 0.69, respectively). Importantly, both measures reflected composition of non-vocalizing nocturnal insects identified via metabarcoding. We show that such automated monitoring tools, based on new technologies, can effectively monitor the success of forest recovery, using robust and reproducible data.


Assuntos
Aprendizado Profundo , Animais , Clima Tropical , Florestas , Biodiversidade , Árvores , Ecossistema , Conservação dos Recursos Naturais
17.
J Abdom Wall Surg ; 2: 11242, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38515586

RESUMO

There is currently no consensus or homogeneous recommendation about the role of the laparoscopic approach in emergent inguinal hernia surgery. The aim of this manuscript is showing our experience and results of laparoscopic approach for emergent groin hernia repair comparing with open approach. A retrospective review of a prospectively maintained database between January 2011 and December 2021 of acute incarcerated groin hernia that were operated at Virgen del Rocio University Hospital. In this period, they were identified 463 patients with groin hernia that required an emergency repair. 454 patients underwent open surgery (group 1) and 36 patients underwent laparoscopic approach (TAPP procedure) (group 2). Median length stay was 1 day in lap group and 2 days in open approach. Reintervention was necessary in 20 cases (4.40%) from group 1 and one (2.27%) from group 2. In laparoscopic approach, no mortality was described but in open approach, 10 patients (2.20%) died. Globally, 58 cases (12.77%) from group 1 and six patients (16.66%) from group 2 presented any complication. Wound infection was higher in group of open repairs (5.94% vs. 2.77%). Non-surgical complications were higher in open approach (19 vs. 0). There is no statistical significance in any of these items. Laparoscopic approach is a safe, feasible and effective therapeutic option for the treatment of incarcerated groin hernia that require emergency surgery, but prospective and randomized comparative studies are needed to establish the best approach.

18.
Molecules ; 17(2): 1448-67, 2012 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-22310167

RESUMO

Communic acids are diterpenes with labdane skeletons found in many plant species, mainly conifers, predominating in the genus Juniperus (fam. Cupresaceae). In this review we briefly describe their distribution and different biological activities (anti- bacterial, antitumoral, hypolipidemic, relaxing smooth muscle, etc.). This paper also includes a detailed explanation of their use as chiral building blocks for the synthesis of bioactive natural products. Among other uses, communic acids have proven useful as chirons for the synthesis of quassinoids (formal), abietane antioxidants, ambrox and other perfume fixatives, podolactone herbicides, etc., featuring shorter and more efficient processes.


Assuntos
Diterpenos/química , Ciclização
19.
Zookeys ; 1121: 175-210, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36760760

RESUMO

The genus Atractus includes 146 species of cryptozoic snakes occurring from Panama to northeastern Argentina. Here, a molecular phylogeny of this genus is presented, which encompasses 29% (= 42; six are included here for the first time) of the species currently recognized. Morphological and phylogenetic support is found for three new species of ground snakes, which are described here based on their unique combination of molecular, meristic, and color pattern characteristics. The name A.arangoi Prado, 1939 is revalidated for a Colombian snake species previously subsumed under A.major Boulenger, 1894 based on new material collected in Ecuador. Reidentifications are provided for Atractus voucher specimens and sequences deposited in GenBank. With these changes, the number of Atractus reported in Ecuador increases from 27 to 31 species. Finally, attention is given to the importance of using a biogeographical framework that includes molecular data and a comprehensive geographic sampling when proposing species limits in complex taxonomic groups.

20.
Environ Sci Pollut Res Int ; 29(56): 84125-84136, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35778662

RESUMO

Due to widespread use of nanoparticles in surfactant-based formulations, their release into the environment and wastewater is unavoidable and toxic for biota and/or wastewater treatment processes. Because of concerns over the environmental impacts of nanofluids, studies of the fate and environmental impacts, hazards, and toxicities of nanoparticles are beginning. However, interactions between nanoparticles and surfactants and the biodegradability of these mixtures have been little studied until now. In this work, the environmental impacts of nanofluids containing mixtures of surfactants and silica nanoparticles were valuated. The systems studied were hydrophilic silica nanoparticles (sizes 7 and 12 nm), a nonionic surfactant (alkyl polyglucoside), an anionic surfactant (ether carboxylic acid), and mixtures of them. The ultimate aerobic biodegradation and the interfacial and adsorption properties of surfactants, nanoparticles, and mixtures during biodegradation were also evaluated. Ultimate biodegradation was studied below and above the CMCs of the individual surfactants. The interfacial and adsorption properties of surfactant solutions containing nanoparticles were influenced by the addition of silica particles. It was determined that silica nanoparticles reduced the capability of the nonionic surfactant alkyl polyglucoside to decrease the surface tension. Thus, silica NPs promoted a considerable increase in the surfactant CMC, whereas the effect was opposite in the case of the anionic surfactant ether carboxylic acid. Increasing concentrations of surfactant and nanoparticles in the test medium caused decreases in the maximum levels of mineralization reached for both types of surfactants. The presence of silica nanoparticles in the medium reduced the biodegradability of binary mixtures containing nonionic and anionic surfactants, and this effect was more pronounced for larger nanoparticles. These results could be useful in modelling the behaviour of nanofluids in aquatic environments and in selecting appropriate nanofluids containing nanoparticles and surfactants with low environmental impact.


Assuntos
Nanopartículas , Dióxido de Silício , Tensoativos/toxicidade , Meio Ambiente , Éteres , Ácidos Carboxílicos
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