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1.
Healthcare (Basel) ; 12(9)2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38727470

RESUMO

Pressure ulcers carry a significant risk in clinical practice. This paper proposes a practical and interpretable approach to estimate the risk levels of pressure ulcers using decision tree models. In order to address the common problem of imbalanced learning in nursing classification datasets, various oversampling configurations are analyzed to improve the data quality prior to modeling. The decision trees built are based on three easily identifiable and clinically relevant pressure ulcer risk indicators: mobility, activity, and skin moisture. Additionally, this research introduces a novel tabular visualization method to enhance the usability of the decision trees in clinical practice. Thus, the primary aim of this approach is to provide nursing professionals with valuable insights for assessing the potential risk levels of pressure ulcers, which could support their decision-making and allow, for example, the application of suitable preventive measures tailored to each patient's requirements. The interpretability of the models proposed and their performance, evaluated through stratified cross-validation, make them a helpful tool for nursing care in estimating the pressure ulcer risk level.

2.
J Hazard Mater ; 463: 132836, 2024 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-37931339

RESUMO

Microorganisms from L. terrestris gut previously exposed to different types of plastic (PET, LDPE, LLDPE, and PS) were studied to be used as probiotics of earthworms in plastic-contaminated soils (LDPE, LLDPE and recycled mulching film) at mesocosm-scale trials. The most abundant morphotypes with enzymatic capacities of interest were identified. Pseudomonas alkylphenolica (PL4) and Pseudomonas putida (PL5) strains were selected to be used as inoculants using Morus alba leaves as carriers to strengthen the intestinal microbiota of earthworms. Culture (selective cetrimide agar medium) and molecular (qPCR) techniques were used to trace the presence of the inoculum in the intestine of the earthworms. Additionally, a metataxonomic analysis was carried out to study the biodiversity and functionality of the earthworm microbiome, and their measure of survival and weight. Probiotics improved the survival rates of earthworms exposed to plastics, which also increased the abundance of microbial groups of interest in plastic bioremediation tasks.


Assuntos
Microbioma Gastrointestinal , Oligoquetos , Animais , Polietileno , Biodiversidade , Solo
3.
ACS Omega ; 8(1): 819-828, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36643454

RESUMO

A new selective fluorogenic chemosensor for Hg2+, which combines a calixarene derivative with a BODIPY core as a fluorescent reporter, is described. The remarkable change in its fluorogenic properties in DMSO and CHCl3 has been analyzed. A study of its spectral properties on dilution, along with molecular modeling studies, allowed us to explain that this behavior involves the formation of a J-dimer, as well as how the sensing mechanism of Hg2+ proceeds.

4.
RSC Adv ; 12(44): 28580-28585, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36330338

RESUMO

Synthetic cathinones are a class of new psychoactive substances whose consumption has increased a lot and is widespread throughout the world. Thus, there is currently a need for rapid and simple detection of these drugs. In particular, detection of synthetic cathinones in oral fluid in drivers can be of great importance in preventing traffic accidents. Herein, we report two probes, based on BODIPY derivatives combined with Cu(ii), which are able to detect these drugs both in water and in oral fluid, by changes in color and fluorescence. The determined limits of detection for ephedrone (as a model drug) are lower than the usual concentrations in saliva after intake of this type of drug. The sensing mechanism seems to be related to the cathinone induced reduction of Cu(ii) to Cu(i) with concomitants changes in the BODIPY structure.

5.
Chem Commun (Camb) ; 58(87): 12248, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36268824

RESUMO

Correction for 'Protection against chemical submission: naked-eye detection of γ-hydroxybutyric acid (GHB) in soft drinks and alcoholic beverages' by Silvia Rodríguez-Nuévalos et al., Chem. Commun., 2020, 56, 12600-12603, https://doi.org/10.1039/D0CC05387B.

6.
Artigo em Inglês | MEDLINE | ID: mdl-36141434

RESUMO

Applications where data mining tools are used in the fields of medicine and nursing are becoming more and more frequent. Among them, decision trees have been applied to different health data, such as those associated with pressure ulcers. Pressure ulcers represent a health problem with a significant impact on the morbidity and mortality of immobilized patients and on the quality of life of affected people and their families. Nurses provide comprehensive care to immobilized patients. This fact results in an increased workload that can be a risk factor for the development of serious health problems. Healthcare work with evidence-based practice with an objective criterion for a nursing professional is an essential addition for the application of preventive measures. In this work, two ways for conducting a pressure ulcer risk assessment based on a decision tree approach are provided. The first way is based on the activity and mobility characteristics of the Braden scale, whilst the second way is based on the activity, mobility and skin moisture characteristics. The results provided in this study endow nursing professionals with a foundation in relation to the use of their experience and objective criteria for quick decision making regarding the risk of a patient to develop a pressure ulcer.


Assuntos
Úlcera por Pressão , Árvores de Decisões , Humanos , Avaliação em Enfermagem/métodos , Úlcera por Pressão/epidemiologia , Úlcera por Pressão/prevenção & controle , Qualidade de Vida , Medição de Risco/métodos , Fatores de Risco
7.
Analyst ; 146(18): 5601-5609, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34378566

RESUMO

Drug-Facilitated Sexual Assault (DFSA) is a problem of considerable dimensions on a global scale. Among the different compounds used in DFSA assaults, 4-hydroxybutyric acid (GHB) is one of the most elusive due to its physical and biological characteristics. Therefore, the development of real-time detection methods to detect GHB not only in drinks but also in urine is very important for personal and social security. Here, we report two new heteroditopic chemosensors capable of recognizing and detecting GHB in soft drinks, alcoholic beverages and synthetic urine. The compounds have two moieties: a trifluoroacetyl group and a thiourea, which are able to interact respectively with the hydroxyl and the carboxylic groups present in the GHB structure. In addition, the distance between these two groups has been optimized to allow a double interaction which guarantees the recognition even in very competitive media such as beverages or urine samples.


Assuntos
Oxibato de Sódio , Bebidas Alcoólicas/análise , Bebidas/análise , Bebidas Gaseificadas , Hidroxibutiratos/análise
8.
J Environ Manage ; 279: 111810, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33341726

RESUMO

Olive Mill Wastewater (OMW) is a polluting residue from the olive oil industry. It is usually stored in open-air unprotected evaporation ponds where their sediments accumulate. This study compares the characteristics of OMW sludges stored for long-time in evaporation ponds and assesses their impact on the underlying soil layer. Physicochemical parameters, toxicity bioassays, and full characterization of the microbial community were analyzed. The extension of the polluting effects was assessed by analysis of toxicity, microbial biomass carbon, and respiration. Geostatistics was used to predict their spatial distribution. Organic matter and polyphenol content besides toxicity levels determine variations between OMW sludges and have a high impact on the microbiota they contain. The microbial community was abundant, diverse, and functionally active. However, the biodegradability of the sludges was hindered by the toxicity levels. Toxicity and biomass carbon were higher on the surface of the ponds than in the soil layer revealing a reduced leach flow and depletion of contaminants. The natural microbiota might be biostimulated by means of applying sustainable and feasible biological treatments in order to favor the OMW sludges bioremediation. These results open up the possibility of solving the environmental concern caused by its storage in similar scenarios, which are common in olive oil-producing countries.


Assuntos
Microbiota , Olea , Biodegradação Ambiental , Resíduos Industriais/análise , Azeite de Oliva , Lagoas , Esgotos , Eliminação de Resíduos Líquidos , Águas Residuárias
9.
Sci Rep ; 10(1): 14912, 2020 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-32913249

RESUMO

The controls that affect the structure and timing of terminations are still poorly understood. We studied a tufa deposit from the Iberian Peninsula that covers Termination II (T-II) and whose chronology was synchronized to speleothem records. We used the same chronology to synchronize ocean sediments from the North Atlantic to correlate major climate events in a common timescale. We identify two stages within T-II. The first stage started with the increase of boreal summer integrated solar insolation, and during this stage three millennial climate oscillations were recorded. These oscillations resulted from complex ocean-atmosphere interactions in the Nordic seas, caused by the progressive decay of Northern Hemisphere ice-sheets. The second stage commenced after a glacial outburst that caused the collapse of the Thermohaline Circulation, a massive Heinrich event, and the onset of the Bipolar Seesaw Mechanism (BSM) that eventually permitted the completion of T-II. The pace of the millennial oscillations during the first stage of T-II controlled the onset of the second stage, when the termination became a non-reversible and global phenomenon that accelerated the deglaciation. During the last the two terminations, the BSM was triggered by different detailed climate interactions, which suggests the occurrence of different modes of terminations.

10.
Chem Commun (Camb) ; 56(83): 12600-12603, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32945322

RESUMO

Two new oxazole derivatives, able to detect γ-hydroxybutyric acid (GHB) in soft drinks and alcoholic beverages, by color and fluorescence changes, are reported.

11.
Sci Total Environ ; 703: 135537, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31761371

RESUMO

The common method for the disposal of olive oil mill wastewater (OMW) has been its accumulation in evaporation ponds where OMW sediments concentrate. Due to the phytotoxic and antimicrobial effect of OMW, leaks from ponds can pollute soils and water bodies. This work focuses on the search for microorganisms that can be used as inocula for bioremediation of polluted matrices in OMW ponds by means of in situ composting. Two fungi isolated from OMW sediments, Aspergillus ochraceus H2 and Scedosporium apiospermum H16, presented suitable capabilities for this use as a consortium. Composting eliminated the phyto- and ecotoxicity of OMW sediments by depleting their main toxic components. Inoculation with the fungal consortium improved the bioremediation efficacy of the technique by hastening the decrease of phytotoxicity and ecotoxicity and enhancing phytostimulant property of compost produced. This procedure constitutes a promising strategy for bioremediation of OMW polluted sites.


Assuntos
Biodegradação Ambiental , Compostagem , Olea , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias , Poluentes Químicos da Água
12.
Water Environ Res ; 91(3): 177-184, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30698899

RESUMO

Water purification is a crucial process in the operation of a municipality. Ensuring that water treatment plants are meeting regulatory requirements is a vital, but complicated and costly process. Because water treatment plant influent and effluent rates are demand driven, and vary both diurnally and seasonally, controlling flow rates for the disinfection stage can be challenging both operationally and economically. Thus, performing large-scale field experiments to verify water quality regulatory criteria such as modal transport time of conservative tracers in a chlorine disinfection contact tank under extreme operating conditions can range from difficult and costly to impossible. In this paper, a computational fluid dynamics (CFD) approach is used to verify the compliance of a water reclamation plant disinfection stage with respect to modal time. CFD allows a large parameter space to be tested without the need to build large physical models or taking functioning systems in a treatment plant offline. This can save facilities large amounts of time and money when designing, optimizing, and developing plants or checking compliance. This paper introduces a hybrid approach of computational analysis of a water reclamation plant's chlorine contact tank in Southern California. The method uses a hybrid approach which combines three-dimensional CFD with hydraulic grade line analysis of the open water surface. Verification cases were compared to experimental measurements at a functioning, full-scale plant with modal contact time differences below 15%. The method was then used to predict residence time distributions (RTDs) for cases which could not be artificially induced at the plant, but represented peak flow conditions that could be expected. PRACTITIONER POINTS: The hybrid 3-dimensional CFD method allows low cost simulation of the disinfection stage. By using head loss calculations to properly define the water level at each section, a steady-state single phase flow simulation can be run in 3D without the need to scale down geometries. This allows for more accurate transport results and parameter studies.


Assuntos
Simulação por Computador , Desinfecção , Hidrodinâmica , Reciclagem , Purificação da Água , Cloro/isolamento & purificação
13.
J Environ Manage ; 192: 57-67, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28135588

RESUMO

The changes in livestock production systems towards intensification frequently lead to an excess of manure generation with respect to the agricultural land available for its soil application. However, treatment technologies can help in the management of manures, especially in N-surplus areas. An integrated slurry treatment system based on solid-liquid separation, aerobic treatment of the liquid and composting the solid fraction was evaluated in a pig farm (sows and piglets) in the South of Spain. Solid fraction separation using a filter band connected to a screw press had low efficiency (38%), which was greatly improved incorporating a rotatory sieve (61%). The depuration system was very efficient for the liquid, with total removal of 84% total solids, 87% volatile solids, and 98% phosphorus. Two composting systems were tested through mechanical turning of: 1- a mixture of solid fraction stored for 1 month after solid-liquid separation and cereal straw; 2- recently-separated solid fraction mixed with cotton gin waste. System 2 was recommended for the farm, as it exhibited a fast temperature rise and a long thermophilic phase to ensure compost sanitisation, and high recovery of nutrients (TN 77%, P and K > 85%) and organic matter (45%). The composts obtained were mature, stable and showed a high degree of humification of their organic matter, absence of phytotoxicity and concentrations of nutrients similar to other composts from pig manure or separated slurry solids. However, the introduction of slurry from piglets into the solid-liquid separation system should be avoided in order to reduce the content of Zn in the compost, which lowers its quality. The slurry separation followed by composting of the solid fraction using a passive windrow system, and aeration of the liquid phase, was the most recommendable procedure for the reduction of GHG emissions on the farm.


Assuntos
Fazendas , Animais , Feminino , Esterco , Solo , Sus scrofa , Suínos
14.
Environ Monit Assess ; 187(3): 58, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25647802

RESUMO

Stratification and loading of fecal indicator bacteria (FIB) were assessed in the main tidal channel of the Ballona Wetlands, an urban salt marsh receiving muted tidal flows, to (1) determine FIB concentration versus loading within the water column at differing tidal flows, (2) identify associations of FIB with other water quality parameters, and (3) compare wetland FIB concentrations to the adjacent estuary. Sampling was conducted four times during spring-tide events; samples were analyzed for FIB and turbidity (NTU) four times over a tidal cycle at pre-allocated depths, depending on the water level. Additional water quality parameters measured included temperature, salinity, oxygen, and pH. Loadings were calculated by integrating the stratified FIB concentrations with water column cross-sectional volumes corresponding to each depth. Enterococci and Escherichia coli were stratified both by concentration and loading, although these variables portrayed different patterns over a tidal cycle. Greatest concentrations occurred in surface to mid-strata levels, during flood tides when contaminated water flowed in from the estuary, and during ebb flows when sediments were suspended. Loading was greatest during flood flows and diminished during low tide periods. FIB concentrations within the estuary often were significantly greater than those within the wetland tide channel, supporting previous studies that the wetlands act as a sink for FIB. For public health water quality monitoring, these results indicate that more accurate estimates of FIB concentrations would be obtained by sampling a number of points within a water column rather than relying only on single surface samples.


Assuntos
Bactérias/crescimento & desenvolvimento , Monitoramento Ambiental/métodos , Microbiologia da Água , Poluição da Água/análise , Áreas Alagadas , Bactérias/classificação , Estudos Transversais , Enterococcus/crescimento & desenvolvimento , Escherichia coli/crescimento & desenvolvimento , Estuários , Fezes/microbiologia , Poluição da Água/estatística & dados numéricos
16.
Org Biomol Chem ; 13(7): 2034-43, 2015 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-25520216

RESUMO

The molecular mechanism of the reaction between N-methyl-3-chloroindole and methyl coumalate yielding carbazole has been studied using DFT methods at the MPWB1K/6-311G(d,p) level in toluene. This reaction is a domino process that comprises three consecutive reactions: (i) a polar Diels-Alder (P-DA) reaction between indole and methyl coumalate yielding two stereoisomeric [2 + 4] cycloadducts (CAs); (ii) the elimination of HCl from these CAs affording two stereoisomeric intermediates; and (iii) the extrusion of CO2 in these intermediates, finally yielding the carbazole. This P-DA reaction proceeds in a completely regioselective and slightly exo selective fashion. In spite of the highly polar character of this P-DA reaction, it presents a high activation enthalpy of 21.8 kcal mol(-1) due to the loss of the aromatic character of the indole during the C-C bond formation. Thermodynamic calculations suggest that the P-DA reaction is the rate-determining step of this domino reaction; in addition, the initial HCl elimination in the formal [2 + 4] CAs is kinetically favoured over the extrusion of CO2. Although the P-DA reaction is kinetically and thermodynamically very unfavourable, the easier HCl and CO2 elimination from the [2 + 4] CAs together with the strong exergonic character of the CO2 extrusion makes the P-DA reaction irreversible. An ELF topological analysis of the bonding changes along the P-DA reaction supports a two-stage one-step mechanism. An analysis of the global DFT reactivity indices at the ground state of the reagents confirms the highly polar character of this P-DA reaction. Finally, the complete regioselectivity of the studied reactions can be explained using the Parr functions.

17.
Org Biomol Chem ; 12(42): 8428-32, 2014 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-25223340

RESUMO

The radical anions of ß-lactams, photogenerated in the presence of DABCO as an electron donor, undergo cycloreversion via N-C4 bond cleavage, back electron transfer and final C2-C3 bond cleavage, leading to olefins. The involved intermediates are 1,4-radical anions and 1,4-biradicals. The experimental observations are consistent with the results of DFT calculations.


Assuntos
beta-Lactamas/química , Alcenos/síntese química , Ânions/química , Transporte de Elétrons , Modelos Moleculares , Processos Fotoquímicos , Piperazinas/química , Espectrometria de Fluorescência
18.
Org Biomol Chem ; 12(6): 895-904, 2014 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-24343422

RESUMO

The NHC catalysed nucleophilic additions of enols to α,ß-unsaturated acyl-azolium intermediates have been investigated using DFT methods at the MPWB1K/6-31G** computational level. In the direct and the conjugate additions, formation of a hydrogen bond (HB) with the carboxyl oxygen is not sufficient to favour the C-C bond formation as a consequence of the low nucleophilic character of enols. Interestingly, when enols form a HB with the chloride counterion, the activation energies associated with the conjugate addition decrease as a consequence of the increased nucleophilic character of enols and the increased electrophilic character of the 'acyl-azolium + Cl' ion pair. Analysis of the DFT reactivity indices allows establishing a base catalysed C-C bond-formation step promoted by the chloride counterion.

19.
Org Biomol Chem ; 11(48): 8357-65, 2013 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-24170110

RESUMO

The thermal and Lewis acid (LA) catalyzed cyclizations of quinone 1 involved in the synthesis of Colombiasin A and Elipsaterosin B have been theoretically studied using DFT methods at the B3LYP/6-311G(d,p) computational level. B3LYP calculations suggest that the formal endo [4 + 2] cycloadduct allowing the synthesis of Colombiasin A is preferentially formed under thermal conditions, while in the presence of the BF3 LA catalyst the formal [5 + 2] cycloadduct is seen, allowing the synthesis of Elipsaterosin B. The BF3 LA catalyst not only accelerates the nucleophilic attack on the C2 carbon of the quinone framework through a more polar C-C bond formation, but also provokes a different electron density rearrangement along the nucleophilic attack favoring the subsequent C-C bond formation at the C4 carbon with the formation of the formal [5 + 2] cycloadduct. ELF bonding analysis along these cyclizations indicates that the C-C single bond formation takes place in the range of 1.91-2.1 Å by C-to-C coupling of two pseudoradical centers. Along the formation of the first C2-C9 single bond, these pseudoradical centers appear at one of the most electrophilic and at one of the most nucleophilic centers of quinone 1, C2 and C9 carbons, respectively. Analysis of the Parr functions suggests that although the most favorable electrophilic/nucleophilic interaction is that involving the C2 carbon of quinone and the C12 carbon of the butadiene framework, the intramolecular nature of the cyclization prevents the corresponding reactive channel.

20.
Photochem Photobiol Sci ; 12(8): 1460-5, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23739752

RESUMO

The aim of the present work is to determine the influence of C5 substitution on the photophysical properties of 2-thiopyrimidines (2-TPyr). For this purpose, 2-thiouracil, 5-t-butyl-2-thiouracil and 2-thiothymine (TU, BTU and TT, respectively) have been selected as target thionucleobases for the experimental studies and, in parallel, for DFT theoretical calculations. The UV spectra displayed by TU, BTU and TT in EtOH were very similar to each other. They showed a maximum around 275 nm and a shoulder at ca. 290 nm. The three 2-TPyr exhibited a strong phosphorescence emission; from the recorded spectra, triplet excited state energies of ca. 307, 304 and 294 kJ mol(-1) were determined for TU, BTU and TT, respectively. Laser excitation at 308 nm gave rise to a broad transient absorption band from 500 nm to 700 nm, which was in principle assigned to triplet-triplet absorption. This assignment was confirmed by energy transfer experiments using biphenyl (ET = 274 kJ mol(-1)) as an acceptor. The triplet lifetimes were 70 ns, 1.1 µs and 2.3 µs, for TU, BTU and TT, respectively. The obtained photophysical data, both in phosphorescence and transient absorption measurements, point to significantly different properties of the TT triplet excited state in spite of the structural similarities. Theoretical calculations at the B3LYP/aug-cc-pVDZ/PCM level agree well with the experimental range of excited state energies and support the ππ* nature of the lowest triplet states.


Assuntos
Tiouracila/química , Timina/análogos & derivados , Modelos Moleculares , Conformação Molecular , Teoria Quântica , Espectrofotometria Ultravioleta , Tiouracila/análogos & derivados , Timina/química
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