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1.
J Sci Food Agric ; 98(12): 4625-4633, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29516500

RESUMO

BACKGROUND: Glass frits with a P2 O5 /K2 O ratio equal to 0.65 and different concentrations of SiO2 (6.5-56.0 wt%), CaO (0-5.1 wt%) and Al2 O3 (0-14.6 wt%) have been prepared and analysed as potential glass fertilizers (GF). RESULTS: P2 O5 and K2 O were leached primarily within the first 5 days but the total amount was dependent on the SiO2 /Al2 O3 ratio of the glass frit. Sustained P2 O5 and K2 O leaching for more than 40 days could be obtained if the glass frit contained more than 7% Al2 O3 . A final glass frit composition (29% SiO2 , 5% CaO, 7% Al2 O3 , 30% P2 O5 , 25% K2 O) was selected and used in an experimental tomato crop of 1 ha area, where one half was fertilized with an NPK conventional fertilizer and the other half with the GF fertilizer. CONCLUSION: After harvesting the tomato crops, the GF fertilizer was found to result in a higher yield than the NPK conventional fertilizer: 59980 kg and 74 360 kg for NKP and GF, respectively. The general characteristics of the harvested tomato fruits and leaves were similar in the two cases and the differences fell within statistical error. No differences in any of the soil characteristics were detected as a result of the use of GF. © 2018 Society of Chemical Industry.


Assuntos
Fertilizantes/análise , Solanum lycopersicum/crescimento & desenvolvimento , Agricultura , Produtos Agrícolas/química , Produtos Agrícolas/crescimento & desenvolvimento , Frutas/química , Frutas/crescimento & desenvolvimento , Solanum lycopersicum/química , Dióxido de Silício/análise , Solo/química
2.
Inorg Chem ; 56(7): 4148-4156, 2017 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-28318233

RESUMO

The mechanism by which Zr-substituted and other transition metal-substituted polyoxometalates (POMs) form covalently linked dimers has been analyzed by means of static density functional theory (DFT) calculations with a continuous solvent model as well as Car-Parrinello molecular dynamics (CPMD) simulations with explicit solvent molecules. The study includes different stages of the process: the formation of the active species by alkalination of the solution and formation of intercluster linkages. CPMD simulations show that the Zr-triaqua precursor, [W5O18Zr(H2O)3]2-, under basic conditions, reacts with hydroxide anions to form Zr-aqua-hydroxo active species, [W5O18Zr(OH)(H2O)]3-. We computed the DFT potential energy profile for dimerization of [W5O18TM(OH)]n- [TM = ZrIV(H2O), ZrIV, TiIV, and WVI] anions. The resulting overall energy barrier is low for ZrIV, moderate for TiIV, and high for WVI. The computed thermodynamic balance favors the dibridged (µOH)2 linkages for ZrIV, the monobridged (µOH) linkage for TiIV, and the monomeric forms for WVI, in agreement with experimentally observed trends. The lowest energy barrier and largest coordination number of Zr-substituted POMs are both a consequence of the flexible coordination environment and larger radius of Zr.

3.
Chemistry ; 22(43): 15280-15289, 2016 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-27531593

RESUMO

The molecular interactions between the CeIV -substituted Keggin anion [PW11 O39 Ce(OH2 )4 ]3- (CeK) and hen egg-white lysozyme (HEWL) were investigated by molecular dynamics simulations. The analysis of CeK was compared with the CeIV -substituted Keggin dimer [(PW11 O39 )2 Ce]10- (CeK2 ) and the ZrIV -substituted Lindqvist anion [W5 O18 Zr(OH2 )(OH)]3- (ZrL) to understand how POM features such as shape, size, charge, or type of incorporated metal ion influence the POM⋅⋅⋅protein interactions. Simulations revealed two regions of the protein in which the CeK anion interacts strongly: cationic sites formed by Arg21 and by Arg45 and Arg68. The POMs chiefly interact with the side chains of the positively charged (arginines, lysines) and the polar uncharged residues (tyrosines, serines, aspargines) via electrostatic attraction and hydrogen bonding with the oxygen atoms of the POM framework. The CeK anion shows higher protein affinity than the CeK2 and ZrL anions, because it is less hydrophilic and it has the right size and shape for establishing interactions with several residues simultaneously. The larger, more negatively charged CeK2 anion has a high solvent-accessible surface, which is sub-optimal for the interaction, while the smaller ZrL anion is highly hydrophilic and cannot efficiently interact with several residues simultaneously.

4.
Cephalalgia ; 36(4): 346-50, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26111946

RESUMO

BACKGROUND: Cranial autonomic symptoms (CAS) seem to appear in around half of migraine patients. OBJECTIVE: Our aim was to analyse the prevalence and profile of CAS, mainly of cranial autonomic parasympathetic symptoms (CAPS), in a series of patients with chronic migraine (CM) according the new criteria for autonomic symptoms in the current IHS classification. PATIENTS AND METHODS: We recruited consecutive CM patients attending our headache clinic. Five CPAS were surveyed: lacrimation, conjunctival injection, eyelid oedema, ear fullness and nasal congestion. They were graded as 0 (absent), 1 (present and mild) and 2 (present and conspicuous); therefore the score in this CAPS scale ranges from 0 to 10 points. As a cranial autonomic sympathetic symptom (CSAS), we also asked about the presence of ptosis. RESULTS: We interviewed 100 CM patients. Their mean age was 45 years (18-63 years); 93 were females. Eighteen had no CAPS, while 82 reported at least one CAPS. There were only six patients with scores higher than 5, the mean and median CAPS being 2.1 and 2, respectively. Prevalence of CAPS was lacrimation (49%), conjunctival injection (44%), eyelid oedema (39%), ear fullness (30%) and nasal congestion (20%). Ptosis was reported by 42. CONCLUSION: These results, by using for the first time an easy quantitative scale, confirm that (mild) CAPS are not the exception but the rule in CM patients. The score in this CAPS scale could be of help as a further endpoint in clinical trials or to be correlated with potential biomarkers of parasympathetic activation in primary headaches.


Assuntos
Doenças do Sistema Nervoso Autônomo/epidemiologia , Transtornos de Enxaqueca/complicações , Adolescente , Adulto , Doenças do Sistema Nervoso Autônomo/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Índice de Gravidade de Doença , Adulto Jovem
5.
Inorg Chem ; 55(12): 6080-4, 2016 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-27232155

RESUMO

A DFT study revealed that the mechanism of alkene epoxidation with hydrogen peroxide catalyzed by Ti-containing polyoxometalates (POMs) depends on the Ti coordination environment: For rigid and hindered Ti centers, the unprecedented ß-oxygen transfer from the titanium hydroperoxo species becomes favored over the α-oxygen one. Improving the model for catalyst description, the calculations were able to reproduce the Arrhenius activation energy values determined in kinetic studies. Unlike protonation, the possible ion-pairing between POMs and countercations has a minor effect on the electrophlicity of the catalyst and, consequently, on the activity of epoxidation.

6.
Angew Chem Int Ed Engl ; 55(51): 15766-15770, 2016 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-27897413

RESUMO

We introduce the class of discrete silver(I)-palladium(II)-oxo nanoclusters with the preparation of {Ag4 Pd13 } and {Ag5 Pd15 }. Both polyanions represent the first examples of noble metal-capped polyoxo-noble-metalates in a fully inorganic assembly, featuring an unprecedented host-guest mode containing hetero- and homometallic Ag-Pd and Ag-Ag bonding interactions. Comprehensive theoretical calculations suggest that the Ag-Pd metallic bonds originate partially from surface confinement of AgI guest ions onto the anionic polyoxopalladate host that is induced by strong electrostatic forces. This work opens the field of fully inorganic silver-palladium-oxo nanoclusters, which can be considered as discrete mixed noble metal precursors for the formation of monodisperse core-shell nanoparticles, with high relevance for catalysis.

7.
Inorg Chem ; 53(2): 778-86, 2014 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-24364825

RESUMO

Static density functional theory (DFT) calculations with a continuous solvent model as well as classical and Car-Parrinello molecular dynamics (MD) simulations with explicit solvent molecules were performed to study the nature of Zr-monosubstituted monomeric and dimeric polyoxometalates (POMs) in water at different pHs. We have analyzed Zr-aqua, -hydroxo, and -aqua-hydroxo species derived from Linqvist- and Keggin-type anions. Both DFT and Car-Parrinello MD methods suggest that the Zr center tends to have coordination number greater than 6 and can bind up to 3 water molecules. Car-Parrinello MD simulations also show that the Zr atom fluctuates within the oxide POM framework, providing a flexible coordination environment. There is a small thermodynamic preference for the Zr-aqua species over the protonated Zr-hydroxo species; however the prevalence of one or the other species might depend on the pH. Classical MD simulations show that H3O(+) interacts mainly with hydroxo ligand, while OH(-) anions prefer the protons of the H2O ligands. In general, an increase of the acidity favors the formation of Zr-aqua species, explaining why dimer dissociation is promoted at low pH. At basic conditions Zr-hydroxo species are generated, providing the reactive groups to form Zr···Zr linkages.

8.
Inorg Chem ; 53(3): 1779-87, 2014 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-24437566

RESUMO

High-valent oxo compounds of transition metals are often implicated as active species in oxygenation of hydrocarbons through carbon-hydrogen bond activation or oxygen transfer and also in water oxidation. Recently, several examples of cobalt-catalyzed water oxidation have been reported, and cobalt(IV) species have been suggested as active intermediates. A reactive species, formally a dicobalt(IV)-µ-oxo polyoxometalate compound [(α2-P2W17O61Co)2O](14-), [(POMCo)2O], has now been isolated and characterized by the oxidation of a monomeric [α2-P2W17O61Co(II)(H2O)](8-), [POMCo(II)H2O], with ozone in water. The crystal structure shows a nearly linear Co-O-Co moiety with a Co-O bond length of ∼1.77 Å. In aqueous solution [(POMCo)2O] was identified by (31)P NMR, Raman, and UV-vis spectroscopy. Reactivity studies showed that [(POMCo)2O]2O] is an active compound for the oxidation of H2O to O2, direct oxygen transfer to water-soluble sulfoxides and phosphines, indirect epoxidation of alkenes via a Mn porphyrin, and the selective oxidation of alcohols by carbon-hydrogen bond activation. The latter appears to occur via a hydrogen atom transfer mechanism. Density functional and CASSCF calculations strongly indicate that the electronic structure of [(POMCo)2O]2O] is best defined as a compound having two cobalt(III) atoms with two oxidized oxygen atoms.


Assuntos
Cobalto/química , Oxigênio/química , Compostos de Tungstênio/química , Água/química , Cristalografia por Raios X , Ligação de Hidrogênio , Modelos Moleculares , Oxirredução , Ozônio/química , Análise Espectral
9.
Ecotoxicol Environ Saf ; 104: 294-301, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24726942

RESUMO

There is a need to develop efficient tools to prevent damage to marine ecosystems due to pollution. Since microalgae play a key role in marine ecosystems, they are considered potentially useful for quick and sensitive toxicity bioassays. In this study an integrative analysis has been carried out of the anti-oxidant enzyme activities of marine microalgae species. Three marine microalgae species (Cylindrotheca closterium, a benthic diatom; Phaeodactylum tricornutum, a diatom which has been used as model organism in toxicity bioassays; and Rhodomonas salina, a cryptophyceae which is considered to present a certain level of heterotrophy) were exposed to selected concentrations of three model pollutants: copper (5 and 10µg L(-1)), atrazine (25 and 50µg L(-1)) and Irgarol (0.5 and 1.0µg L(-1)). These pollutant concentrations are environmentally relevant for coastal ecosystems, and have been selected for checking the efficiency of the reactive oxygen intermediate (ROI) scavenging enzyme system of these organisms. Superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APx) and glutathione peroxidase (GPx) activities were measured at the end of 24h exposure. The integrated biomarker response (IBR) index - in our case for oxidative stress - has been employed to evaluate the ROI-scavenging enzyme system for each species and each treatment. In general, the SOD and CAT enzyme activities measured were higher in exposed populations than in controls, whereas APx and GPx activities showed the opposite trend. These microalgae showed significant responses of oxidative stress biomarkers at environmentally relevant concentrations for the assayed pollutants and short exposure periods, conditions that most other model organisms cannot match. Therefore microalgae present clear advantages over other species for their prospective employment in an "early warning system".


Assuntos
Biomarcadores/metabolismo , Microalgas/efeitos dos fármacos , Microalgas/enzimologia , Poluentes Químicos da Água/toxicidade , Atrazina/toxicidade , Cobre/toxicidade , Monitoramento Ambiental , Estresse Oxidativo/efeitos dos fármacos , Oxirredutases/metabolismo , Espécies Reativas de Oxigênio , Triazinas/toxicidade
10.
Environ Monit Assess ; 186(8): 4647-54, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24648102

RESUMO

Marine epibionts are organisms that grow on submerged surfaces. Those found on seagrass leaves are especially important because of their interactions with the plants, their contribution to primary production in these ecosystems, and their role as food source for heterotrophic fauna. Given the relative lack of ecotoxicological studies on epibionts, the aim of this study is to evaluate the effect of environmental pollution on epiphytes experimentally attached to artificial devices (mimes) consisting of thermally-sealed silicone tubes supported on bamboo sticks that mimic the morphology of seagrasses and serve as an anchor surface for marine epibionts. Mimes were installed on the sea floor in subtidal waters of the Rio San Pedro (Cádiz), collected after 28 days, and incubated in the laboratory with environmental concentrations of atrazine (herbicide), Irgarol (anti-fouling substance), and copper. Tube-dwelling diatoms formed the major component of the epiphyte community. Average surface covering, chlorophyll, and biomass content did not show significant differences between controls and treatments. The glutathione peroxidase activity increased significantly with 4 µg L(-1) of atrazine and 5 µg L(-1) of copper. This enzymatic activity increase seems to be sufficient to prevent oxidative cellular damage by removing reactive oxygen substances produced by oxidative stress; in addition to this enzyme, there might be other antioxidant enzymes which have not been measured in this study, that have also protected the organism from oxidative damage. Thus, the measurement of antioxidant enzymatic activity in epiphytes may be a useful toxicity indicator for coastal biomonitoring.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/toxicidade , Atrazina/análise , Atrazina/toxicidade , Bioensaio , Clorofila/metabolismo , Cobre/toxicidade , Ecossistema , Ecotoxicologia , Estresse Oxidativo , Triazinas/toxicidade , Poluentes Químicos da Água/análise
11.
Angew Chem Int Ed Engl ; 53(44): 11974-8, 2014 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-25220307

RESUMO

The three novel, discrete palladium(II)-oxo clusters [CaPd12O8(PhAsO3)8](6-) (CaPd12), [SrPd12O6(OH)3(PhAsO3)6(OAc)3](4-) (SrPd12), and [BaPd15O10(PhAsO3)10](8-) (BaPd15) encapsulating alkaline earth metal ions were prepared and fully characterized by a multitude of solution and solid-state physicochemical techniques. We have discovered a structure-directing template effect induced by the respective size of the alkaline earth guest ion, which determines the detailed condensation arrangement of the peripheral Pd(II)-oxo shell. The unprecedented SrPd12 with an open-shell type structure is of particular importance and reflects a successful strategy for deliberate design of new structural classes of polyoxo-noble-metalates. Furthermore, the unusual acetate-water ligand exchange phenomenon renders SrPd12 as a promising candidate for noble-metal-based catalysis.

12.
An Sist Sanit Navar ; 47(1)2024 Mar 07.
Artigo em Espanhol | MEDLINE | ID: mdl-38451043

RESUMO

Catamenial pneumothorax is a spontaneous recurrent pneumothorax that occurs in women of reproductive age and in temporal relationship with the menses. It usually occurs within 24 hours before or 72 hours after the start of the menstrual cycle; however, multiple variations have been described in terms of the temporal relationship. To date, it is considered a rare condition; this may be justified by the limited available knowledge on this disease leading to misdiagnosis. Often, making a diagnosis of catamenial pneumothorax is complicated; it mainly depends on the medical history; also, it may be a surgical or histopathological diagnosis. Management strategies for catamenial pneumothorax may include combinations of hormonal therapy, pleurodesis, lung parenchyma resection, and diaphragm resection/repair. The aim of reporting this atypical case of catamenial pneumothorax is to highlight the relevance of having the adequate knowledge on this entity so it does not go unnoticed despite its apparent low incidence.


Assuntos
Pneumotórax , Humanos , Feminino , Pneumotórax/terapia , Doenças Raras
13.
Ecol Evol ; 14(2): e10879, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38343567

RESUMO

Stingless bees are important pollinators in tropical forests. Yet, we know little about their foraging behavior (e.g., their nutritional requirements or their floral sources visited for resource collection). Many stingless bees not only depend vitally on pollen and nectar for food but also on resin for nest building and/or defense. However, it is unclear whether the large effort devoted to collecting resin as a non-food resource by certain stingless bees affects their foraging behavior. Therefore, in this study, we analyzed differences in foraging patterns (i.e., foraging activity, proportion of collected resources, and specialization in plants visited) and resource nutritional composition (i.e., sucrose amount in nectar and amino acids in pollen) of seven different stingless bee species (eleven wild colonies) in north-western Ecuador with a particular focus on the role of resin collection. We found that species with a high resin intake tended to be more active than species with a low resin intake. The foragers per minute invested for pollen collection were similar across all species. Sucrose intake per minute differed between some species but was not affected by increased resin intake. Interestingly, high and low resin collectors partly differed in the plants visited for pollen collection. Pollen amino acid profiles largely, but not completely, overlapped between the two resin collection groups. Our findings show that the foraging patterns and plant choices of stingless bees may vary depending on their resin intake, highlighting the need for more research focusing on resin collection and use by stingless bees.


Las abejas sin aguijón son polinizadores importantes en los bosques tropicales. Sin embargo, sabemos poco acerca de su comportamiento de forrajeo (e.g., sus requisitos nutricionales o las fuentes florales visitadas para la recolección de recursos). Muchas abejas sin aguijón dependen vitalmente no solo de polen y de néctar como alimento, sino también de resinas para la construcción de su nido y/o defensa. Sin embargo, no está claro si el gran esfuerzo dedicado a la recolección de resina como recurso no alimentario de ciertas abejas sin aguijón afecta su comportamiento de forrajeo. Por lo tanto, en este estudio, analizamos las diferencias en los patrones de forrajeo (i.e., actividad de forrajeo, proporción de recursos recolectados y especialización en las plantas visitadas) y la composición nutricional de los recursos recolectados (i.e., cantidad de sacarosa en el néctar y de aminoácidos en el polen) de siete especies diferentes de abejas sin aguijón (once colonias silvestres) en el noroeste de Ecuador, con un enfoque particular en el rol de la recolección de resina. Encontramos que las especies con una recolección alta de resina tienden a ser más activas que las especies con una recolección baja de resina. La cantidad de forrajeadores por minuto dedicada a la recolección de polen fue similar en todas las especies. La ingesta de sacarosa por minuto difirió entre algunas especies, pero no se vio afectada por un aumento en la recolección de resina. Interesantemente, las abejas con una recolección alta y baja de resina difirieron parcialmente en las plantas que visitaron para la recolección de polen. Entre los dos grupos de recolección de resina también hubo diferencias con respecto al perfil de aminoácidos en el polen que recolectaron. El perfil de aminoácidos se sobrelapaba, pero no completamente, entre los dos grupos. Nuestros resultados muestran que los patrones de forrajeo y las elecciones de plantas de las abejas sin aguijón pueden variar según su consumo de resina, destacando la necesidad de hacer más investigaciones centradas en la recolección y el uso de resina por parte de las abejas sin aguijón.

14.
Chemistry ; 19(3): 950-6, 2013 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-23180690

RESUMO

The nature and magnitude of the magnetic anisotropy of heptacoordinate mononuclear Ni(II) and Co(II) complexes were investigated by a combination of experiment and ab initio calculations. The zero-field splitting (ZFS) parameters D of [Ni(H(2)DAPBH)(H(2)O)(2)](NO(3))(2)⋅2 H(2)O (1) and [Co(H(2)DAPBH)(H(2)O)(NO(3))](NO(3)) [2; H(2)DAPBH = 2,6-diacetylpyridine bis- (benzoyl hydrazone)] were determined by means of magnetization measurements and high-field high-frequency EPR spectroscopy. The negative D value, and hence an easy axis of magnetization, found for the Ni(II) complex indicates stabilization of the highest M(S) value of the S = 1 ground spin state, while a large and positive D value, and hence an easy plane of magnetization, found for Co(II) indicates stabilization of the M(S) = ±1/2 sublevels of the S = 3/2 spin state. Ab initio calculations were performed to rationalize the magnitude and the sign of D, by elucidating the chemical parameters that govern the magnitude of the anisotropy in these complexes. The negative D value for the Ni(II) complex is due largely to a first excited triplet state that is close in energy to the ground state. This relatively small energy gap between the ground and the first excited state is the result of a small energy difference between the d(xy) and d(x(2)-y(2)) orbitals owing to the pseudo-pentagonal-bipyramidal symmetry of the complex. For Co(II), all of the excited states contribute to a positive D value, which accounts for the large magnitude of the anisotropy for this complex.

15.
Chemphyschem ; 14(10): 2164-73, 2013 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-23592401

RESUMO

Lateral-flow immunosensing devices continue to be the most successful commercial realization of analytical microdevices. They owe their success to their simplicity, which significantly depends on the capillary-driven flow and versatile technological platform that lends itself to fast and low-cost product development. To compete with such a convenient product, microsystems can benefit from simple-to-operate fluid manipulation. We show that the capillary-driven flow in microchannels can be manipulated with electrochemically activated valves with no moving parts. These valves consist of screen-printed electrode pairs that are transversal to the flow. One of the electrodes is solvent-etched to produce a superhydrophobic surface that provides passive stopping and facilitates low-voltage (~1 V) actuation of the flow via electrowetting. The operation of such valves in the stop-go mode, with a response time between 2 and 45 sec depending on the type and concentration of salt, is demonstrated. Mechanistic investigations indicated that the response depends on at least three phenomena that contribute to electrocapillarity: the electrochemical double-layer capacitance, specific counterion adsorption, and possible electrohydrodynamic effects.


Assuntos
Equipamentos para Diagnóstico , Técnicas Eletroquímicas , Técnicas Analíticas Microfluídicas , Técnicas Eletroquímicas/instrumentação , Eletrodos , Técnicas Analíticas Microfluídicas/instrumentação , Tamanho da Partícula , Sistemas Automatizados de Assistência Junto ao Leito , Propriedades de Superfície
16.
Artigo em Inglês | MEDLINE | ID: mdl-24121740

RESUMO

Toxic effects of copper, atrazine and irgarol were evaluated on epiphytes attached to mimes (artificial devices that mimic the morphology of seagrasses) in order to check sensitivity of this biological group. Tube-dwelling diatoms were the major component of the epiphyte community. Superoxide dismutase activity was enhanced by exposure to 25 and 50 µg L-1 of atrazine; the organism generates this antioxidant response to prevent cellular damage by removing reactive oxygen substances produced by oxidative stress. The measurement of antioxidant enzymatic activity in epiphytes could be a useful technique for ecotoxicology monitoring in marine coastal environments.

17.
PNAS Nexus ; 2(1): pgac283, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36712929

RESUMO

Previous research suggests that it is difficult to maintain cooperation in a large society when there is a strong hierarchical structure. In this study, we implement online human experiments to study the effects of exogenous variation in a particular notion of hierarchy on cooperation and conflict within groups. We demonstrate how cooperation can be maintained when collective action is accompanied by dyadic conflicts whose outcome feeds back on the hierarchical rank of the contestants. We find that the majority of individuals take part in conflicts and that highly ranked individuals mostly cooperate and engage in conflicts as a way to punish noncooperators. As a consequence, stable hierarchical groups can arise and maintain high levels of cooperation. Our results are in agreement with the prediction of earlier theoretical models on hierarchical societies and are relevant to understanding the interplay of hierarchy, cooperation, and conflict.

18.
Cir Esp (Engl Ed) ; 101(3): 208-212, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35792247

RESUMO

Congenital diaphragmatic hernia incidence is one in 3000 live births, Bochdalek hernia occurs through a posterolateral defect. It is very rare in adults. We present a case of late relapsed one diagnosed in an adult male. He underwent an open intervention of Bochdalek hernia at first day of life and required reintervention at seventh month due to recurrence. Now, computerized tomography scan demonstrates a right diaphragmatic defect with intrathoracic hydronephrotic kidney. Nephrectomy was performed with Video-assisted Thoracic Surgery using laparoscopic ports and material. The diaphragmatic defect was closed with a polypropylene mesh. The patient was discharged after 72 h.


Assuntos
Hérnias Diafragmáticas Congênitas , Humanos , Masculino , Adulto , Hérnias Diafragmáticas Congênitas/cirurgia , Nefrectomia , Tomografia Computadorizada por Raios X , Cirurgia Torácica Vídeoassistida , Rim/anormalidades , Rim/cirurgia
19.
J Clin Pathol ; 76(4): 266-273, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34725195

RESUMO

AIMS: Several classification systems are used for pseudomyxoma peritonei. The four-tiered classification system proposed by Peritoneal Surface Oncology Group International (PSOGI) and the two-tiered proposed by the eighth edition of the American Joint Committee on Cancer (AJCC) result from evolution in terminology and pathological insight. The aim is to evaluate the impact of PSOGI and eighth edition of the AJCC classifications on survival. METHODS: Pathological slides were reviewed from a prospectively maintained database including patients treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for an appendiceal mucinous neoplasm with peritoneal dissemination between January 2009 and December 2019. Patients were reclassified according to PSOGI and AJCC eighth edition criteria. Survival analysis evaluated the impact of each classification system on overall survival (OS) and disease-free survival (DFS) while the concordance-index evaluated their predictive power. RESULTS: 95 patients were identified; 21.1% were reclassified as acellular mucin, 55.8% as low-grade mucinous carcinoma peritonei, 8.4% as high-grade MCP (HGMCP) and 14 as HGMCP with signet ring cells. Median OS was not reached, 5-year OS and DFS were 86.1% and 51.5%, respectively. Multivariate analysis revealed significant associations with OS (PSOGI: HR 10.2, p=0.039; AJCC: HR 7.7, p=0.002) and DFS (PSOGI: HR 12.7, p=0.001; AJCC: HR 3.7, p<0.001). The predictive capacity of both classification systems was unacceptable for OS and DFS (concordance-index values <0.7). CONCLUSIONS: Both classification systems behaved similarly when stratifying our series into prognostic groups. The PSOGI classification provides better histopathological description, but histology alone is insufficient for adequate patient prognostication.


Assuntos
Neoplasias do Apêndice , Apêndice , Neoplasias Císticas, Mucinosas e Serosas , Neoplasias Peritoneais , Pseudomixoma Peritoneal , Humanos , Apêndice/patologia , Neoplasias Peritoneais/terapia , Neoplasias Peritoneais/patologia , Neoplasias do Apêndice/terapia , Neoplasias do Apêndice/patologia , Pseudomixoma Peritoneal/terapia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
20.
Sci Data ; 10(1): 916, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38123598

RESUMO

Type 1 diabetes mellitus (T1D) patients face daily difficulties in keeping their blood glucose levels within appropriate ranges. Several techniques and devices, such as flash glucose meters, have been developed to help T1D patients improve their quality of life. Most recently, the data collected via these devices is being used to train advanced artificial intelligence models to characterize the evolution of the disease and support its management. Data scarcity is the main challenge for generating these models, as most works use private or artificially generated datasets. For this reason, this work presents T1DiabetesGranada, an open under specific permission longitudinal dataset that not only provides continuous glucose levels, but also patient demographic and clinical information. The dataset includes 257 780 days of measurements spanning four years from 736 T1D patients from the province of Granada, Spain. This dataset advances beyond the state of the art as one the longest and largest open datasets of continuous glucose measurements, thus boosting the development of new artificial intelligence models for glucose level characterization and prediction.


Assuntos
Diabetes Mellitus Tipo 1 , Humanos , Inteligência Artificial , Glicemia , Automonitorização da Glicemia/métodos , Glucose , Qualidade de Vida
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