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1.
Sci Rep ; 12(1): 10529, 2022 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-35732864

RESUMO

Resource recovery and prevention of environmental pollution are key goals for sustainable development. It is widely reported that agro-industrial activities are responsible for the discharge of billions of liters of wastewater to the environment. Anaerobic digestion of these energy rich agro-industrial wastewaters can simultaneously mitigate environmental pollution and recover embedded energy as methane gas. In this study, an assessment of mono- and co-digestion of cheese whey wastewater (CWW) and poultry slaughterhouse wastewater (PSW) was conducted in 2.25-L lab-scale anaerobic digesters. Treatment combinations evaluated included CWW (R1), PSW (R2), 75:25 CWW:PSW (R3), 25:75 CWW:PSW (R4), and 50:50 CWW:PSW (R5). The digestion efficiencies of the mixed wastewaters were compared to the weighted efficiencies of the corresponding combined mono-digested samples. R4, with a mixture of 25% CWW and 75% PSW, achieved the greatest treatment efficiency. This corresponded with an average biodegradability of 84%, which was greater than for R1 and R2 at 68.5 and 71.9%, respectively. Similarly, R4 produced the highest average cumulative methane value compared to R1 and R2 at 1.22× and 1.39× for similar COD loading, respectively. The modified Gompertz model provided the best fit for the obtained methane production data, with lag time decreasing over progressive treatment cycles. PCoA and heatmap analysis of relative microbial abundances indicated a divergence of microbial communities based on feed type over the treatment cycles. Microbial community analysis showed that genus Petrimonas attained the highest relative abundance (RA) at up to 38.9% in the first two cycles, then subsequently decreased to near 0% for all reactors. Syntrophomonas was highly abundant in PSW reactors, reaching up to 36% RA. Acinetobacter was present mostly in CWW reactors with a RA reaching 56.5%. The methanogenic community was dominated by Methanothrix (84.3-99.9% of archaea). The presence of phosphate and Acinetobacter in CWW feed appeared to reduce the treatment efficiency of associated reactors. Despite Acinetobacter being strictly aerobic, previous and current results indicate its survival under anaerobic conditions, with the storage of phosphate likely playing a key role in its ability to scavenge acetate during the digestion process.


Assuntos
Queijo , Águas Residuárias , Matadouros , Anaerobiose , Animais , Reatores Biológicos , Digestão , Metano , Fosfatos , Aves Domésticas , Esgotos , Eliminação de Resíduos Líquidos/métodos , Soro do Leite , Proteínas do Soro do Leite
3.
Carbohydr Polym ; 249: 116868, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32933693

RESUMO

Cellulose/TiO2 nanocomposite was synthesized using coagulation in sodium hydroxide-thiourea-urea aqueous solution medium by precipitation method. This method was accomplished green and cost-effective for the fabrication of composite nanomaterials. Structure, morphology and optical properties of the nanocomposite were characterized by X-ray diffraction, energy dispersive X-ray spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, and ultraviolet diffuse reflectance spectra respectively. XRD results showed the anatase structure of TiO2 while FESEM micrograph showed evidence of particle size ranging from 20 to 40 nm for cellulose/TiO2 nanocomposite. The Fourier transfer infrared spectroscopy investigation reveals that the TiO2 is bound to hydroxyl groups to the cellulose by hydrogen bonding. The optical energy bandgap is found to be 2.71 eV for nanocomposite from the UV-DRS. The mechanical strength of the composites gently escalated with the addition of TiO2 nanoparticles into cellulose polymer matrix. Cellulose/TiO2 nanocomposite was screened for their in vitro antibacterial activity against Staphylococcus aureus and Escherichia coli bacteria have been investigated. Additionally, the results obtained from in silico molecular docking studies confirm the interaction of nanocomposite with proteins, were in good agreement with the experimental data. This finding provides a novel and simple method for the synthesis of cellulose/TiO2 nanocomposite as functional biomaterials.


Assuntos
Antibacterianos/farmacologia , Celulose/química , Escherichia coli/efeitos dos fármacos , Nanopartículas Metálicas/química , Nanocompostos/administração & dosagem , Staphylococcus aureus/efeitos dos fármacos , Titânio/química , Antibacterianos/química , Simulação por Computador , Técnicas In Vitro , Simulação de Acoplamento Molecular , Nanocompostos/química
4.
Curr Oncol ; 25(4): 262-274, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30111967

RESUMO

The annual Eastern Canadian Gastrointestinal Cancer Consensus Conference 2017 was held in St. John's, Newfoundland and Labrador, 28-30 September. Experts in radiation oncology, medical oncology, surgical oncology, and cancer genetics who are involved in the management of patients with gastrointestinal malignancies participated in presentations and discussion sessions for the purpose of developing the recommendations presented here. This consensus statement addresses multiple topics in the management of gastric, rectal, and colon cancer, including ■ identification and management of hereditary gastric and colorectal cancer (crc);■ palliative systemic therapy for metastatic gastric cancer;■ optimum duration of preoperative radiation in rectal cancer-that is, short- compared with long-course radiation;■ management options for peritoneal carcinomatosis in crc;■ implications of tumour location for treatment and prognosis in crc; and■ new molecular markers in crc.


Assuntos
Neoplasias Colorretais , Canadá , Neoplasias Colorretais/patologia , Consenso , História do Século XXI , Humanos
5.
Ultrasonics ; 64: 162-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26385842

RESUMO

A fully non-contact single-sided air-coupled and laser ultrasonic non-destructive system based on the generation and detection of Lamb waves is implemented for the characterization of A0 Lamb wave mode dispersion in a composite plate. An air-coupled transducer (ACT) radiates acoustic pressure on the surface of the composite and generates Lamb waves within the structure. The out-of-plane velocity of the propagating wave is measured using a laser Doppler vibrometer (LDV). In this study, the non-contact automated system focuses on measuring A0 mode frequency-wavenumber, phase velocity dispersion curves using Snell's law and group velocity dispersion curves using Morlet wavelet transform (MWT) based on time-of-flight along different wave propagation directions. It is theoretically demonstrated that Snell's law represents a direct link between the phase velocity of the generated Lamb wave mode and the coincidence angle of the ACT. Using Snell's law and MWT, the former three dispersion curves of the A0 mode are easily and promptly generated from a set of measurements obtained from a rapid ACT angle scan experiment. In addition, the phase velocity and group velocity polar characteristic wave curves are also computed to analyze experimentally the angular dependency of Lamb wave propagation. In comparison with the results from the theory, it is confirmed that using the ACT/LDV system and implementing simple Snell's law method is highly sensitive and effective in characterizing the dispersion curves of Lamb waves in composite structures as well as its angular dependency.

6.
Ultrasonics ; 61: 62-70, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25847611

RESUMO

A rapid, fully non-contact, hybrid system which encompasses an air-coupled transducer (ACT) and a laser Doppler vibrometer (LDV) is presented for profiling A0 Lamb wave dispersion of an isotropic aluminum plate. The ACT generates ultrasonic pressure incident upon the surface of the plate. The pressure waves are partially refracted into the plate. The LDV is employed to measure the out-of-plane velocity of the excited Lamb wave mode at some distances where the Lamb waves are formed in the plate. The influence of the ACT angle of incidence on Lamb wave excitation is investigated and Snell's law is used to directly compute Lamb wave dispersion curves including phase and group velocity dispersion curves in aluminum plates from incident angles found to generate optimal A0 Lamb wave mode. The measured curves are compared to results obtained from a two-dimensional (2-D) Fast Fourier transform (FFT), Morlet wavelet transform (MWT) and theoretical predictions. It was concluded that the experimental results obtained using Snell's law concept are well in accordance with the theoretical solutions. The high degree of accuracy in the measured data with the theoretical results proved a high sensitivity of the air-coupled and laser ultrasound in characterizing Lamb wave dispersion in plate-like structures. The proposed non-contact hybrid system can effectively characterize the dispersive relation without knowledge of neither the materials characteristics nor the mathematical model.

7.
Transl Psychiatry ; 4: e387, 2014 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-24780921

RESUMO

Elevated glucocorticoid levels and sign tracking (ST) in Pavlovian conditioning are potential biomarkers of compulsive behaviors such as addiction. As overeating is sometimes viewed as a form of addictive behavior, we hypothesized that murine Pavlovian sign trackers would have a greater propensity to overeat and develop obesity. Using a food reward in the classical conditioning paradigm, we show that ST behavior is a robust conditioned response but not a predictor of eating and growth trajectories in mice, thus challenging the view that the development of obesity and drug addiction depend on identical mechanisms. This interpretation was supported by experiments which showed that overweight mice do not display cross-sensitization to an addictive drug (morphine), and conversely, that overweight morphine-sensitized animals do not overconsume a highly rewarding food. Although the rewarding/motivational effects of both food and drugs of abuse are mediated by similar neurochemical mechanisms, obesity and drug addiction represent a summation of other dysfunctional input and output pathways that lead to the emergence of two distinct disorders, each of which would deserve a specific pharmacotherapeutic approach.


Assuntos
Comportamento Aditivo/fisiopatologia , Comportamento Animal/fisiologia , Sensibilização do Sistema Nervoso Central/fisiologia , Condicionamento Clássico/fisiologia , Hiperfagia/fisiopatologia , Sobrepeso/fisiopatologia , Animais , Comportamento Animal/efeitos dos fármacos , Sensibilização do Sistema Nervoso Central/efeitos dos fármacos , Alimentos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Morfina/administração & dosagem , Morfina/farmacologia , Entorpecentes/administração & dosagem , Entorpecentes/farmacologia , Recompensa
8.
Nano Lett ; 14(2): 541-6, 2014 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-24387246

RESUMO

The modified phonon dispersion is of importance for understanding the origin of the reduced heat conductivity in nanowires. We have measured the phonon dispersion for 50 nm diameter InSb (111) nanowires using time-resolved X-ray diffraction. By comparing the sound speed of the bulk (3880 m/s) and that of a classical thin rod (3600 m/s) to our measurement (2880 m/s), we conclude that the origin of the reduced sound speed and thereby to the reduced heat conductivity is that the C44 elastic constant is reduced by 35% compared to the bulk material.

9.
Struct Dyn ; 1(1): 014502, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26913673

RESUMO

We report on measurements of the light absorption efficiency of InSb nanowires. The absorbed 70 fs light pulse generates carriers, which equilibrate with the lattice via electron-phonon coupling. The increase in lattice temperature is manifested as a strain that can be measured with X-ray diffraction. The diffracted X-ray signal from the excited sample was measured using a streak camera. The amount of absorbed light was deduced by comparing X-ray diffraction measurements with simulations. It was found that 3.0(6)% of the radiation incident on the sample was absorbed by the nanowires, which cover 2.5% of the sample.

10.
BJOG ; 120(11): 1308-20, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23834505

RESUMO

BACKGROUND: Endometriosis is found in 0.5-5% of fertile women and 25-40% of infertile women. It is known that endometriosis is associated with infertility, but there is uncertainty whether women with endometriosis have adverse pregnancy outcomes in in vitro fertilisation (IVF) treatment. OBJECTIVES: To explore the association between endometriosis and IVF outcome. SEARCH STRATEGY: Searches were conducted on MEDLINE, EMBASE, Cochrane Library and Web of Science (inception, December 2012) in all languages, together with reference lists of retrieved papers. SELECTION CRITERIA: Studies comparing IVF outcome in women with endometriosis with women without endometriosis. Patients were classified by stage of endometriosis. The outcomes were fertilisation, implantation, clinical pregnancy and live birth rates. Study selection was conducted independently by two reviewers. The Newcastle-Ottawa Quality Assessment Scale was used for quality assessment. DATA COLLECTION AND ANALYSIS: Data extraction was conducted independently by two reviewers. Relative risks from individual studies were meta-analysed. MAIN RESULTS: Twenty-seven observational studies were included, comprising 8984 women. Meta-analysis of these studies showed that fertilisation rates were reduced in stage I/II of endometriosis (relative risk [RR] = 0.93, 95% confidence interval [95% CI] 0.87-0.99, P = 0.03). There was a decrease in the implantation rate (RR = 0.79, 95% CI 0.67-0.93, P = 0.006) and clinical pregnancy rate (RR = 0.79, 95% CI 0.69-0.91, P = 0.0008) in women with stage III/IV endometriosis undergoing IVF treatment. CONCLUSION: The presence of severe endometriosis (stage III/IV) is associated with poor implantation and clinical pregnancy rates in women undergoing IVF treatment.


Assuntos
Endometriose/complicações , Fertilização in vitro , Doenças Uterinas/complicações , Implantação do Embrião , Endometriose/classificação , Feminino , Humanos , Infertilidade Feminina/etiologia , Infertilidade Feminina/terapia , Nascido Vivo , Gravidez , Taxa de Gravidez , Índice de Gravidade de Doença , Doenças Uterinas/classificação
11.
Phys Rev Lett ; 110(18): 183001, 2013 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-23683194

RESUMO

In the 1980s Demkov, Kondratovich, and Ostrovsky and Kondratovich and Ostrovsky proposed an experiment based on the projection of slow electrons emitted by a photoionized atom onto a position-sensitive detector. In the case of resonant excitation, they predicted that the spatial electron distribution on the detector should represent nothing else but a magnified image of the projection of a quasibound electronic state. By exciting lithium atoms in the presence of a static electric field, we present in this Letter the first experimental photoionization wave function microscopy images where signatures of quasibound states are evident. Characteristic resonant features, such as (i) the abrupt change of the number of wave function nodes across a resonance and (ii) the broadening of the outer ring of the image (associated with tunneling ionization), are observed and interpreted via wave packet propagation simulations and recently proposed resonance tunneling mechanisms. The electron spatial distribution measured by our microscope is a direct macroscopic image of the projection of the microscopic squared modulus of the electron wave that is quasibound to the atom and constitutes the first experimental realization of the experiment proposed 30 years ago.

12.
Rev Sci Instrum ; 83(1): 013305, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22299943

RESUMO

DIAM (Dispositif d'Irradiation d'Agrégats Moléculaires) is a new experimental setup devoted to investigate processes induced by irradiation at the nanoscale. The DIAM apparatus is based on a combination of techniques including a particle beam from high-energy physics, a cluster source from molecular and cluster physics, and mass spectrometry form analytical sciences. In this paper, we will describe the first part of the DIAM apparatus that consists of an ExB double spectrometer connected to a cluster ion source based on a continuous supersonic expansion in the presence of ionizing electrons. This setup produces high intensities of energy-and-mass selected molecular cluster ion beams (1000 s of counts s(-1)). The performance of the instrument will be shown through measurements of 6-8 keV beams of protonated water clusters, (H(2)O)(n)H(+) (n = 0-21) and mixed protonated (or deprotonated) water-pyridine cluster ions: PyrH(+)(H(2)O)(n) (n = 0-15), Pyr(2)H(+) (H(2)O)(n) (n = 0-9), and (Pyr-H)(+) (H(2)O).


Assuntos
Gases/química , Espectrometria de Massas/instrumentação , Nanotecnologia/instrumentação , Aceleração , Prótons , Piridinas/química , Água/química
13.
Artigo em Inglês | MEDLINE | ID: mdl-22255669

RESUMO

In this paper, we present a new seizure detection algorithm and the associated CMOS circuitry implementation. The proposed low-power seizure detector is a good candidate for an implantable epilepsy prosthesis. The device is designed for patient-specific seizure detection with a one variable parameter. The parameter value is extracted from a single seizure that is subsequently excluded from the validation phase. A two-path system is also proposed to minimize the detection delay. The algorithm is first validated using MATLAB® tools and then implemented and validated using circuits designed in a standard 0.18-µm CMOS process with a total power dissipation of 7.08 µW. A total of 13 seizures from two drug-resistant epileptic patients are assessed using the proposed algorithm and resulted in 100% sensitivity and a mean detection delay of 9.7 s after electrical onset.


Assuntos
Algoritmos , Diagnóstico por Computador/instrumentação , Eletroencefalografia/instrumentação , Convulsões/diagnóstico , Processamento de Sinais Assistido por Computador/instrumentação , Transistores Eletrônicos , Adulto , Fontes de Energia Elétrica , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
14.
Rev Sci Instrum ; 81(12): 125111, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21198055

RESUMO

We propose a simple and general analytical model describing the operation of a velocity-map-imaging spectrometer. We show that such a spectrometer, possibly equipped with a magnifying lens, can be efficiently modeled by combining analytical expressions for the axial potential distributions along with a transfer matrix method. The model leads transparently to the prediction of the instrument's operating conditions as well as to its resolution. A photoelectron velocity-map-imaging spectrometer with a magnifying lens, built and operated along the lines suggested by the model has been successfully employed for recording images at threshold photoionization of atomic lithium. The model's reliability is demonstrated by the fairly good agreement between experimental results and calculations. Finally, the limitations of the analytical method along with possible generalizations, extensions, and potential applications are also discussed. The model may serve as a guide for users interested in building and operating such spectrometers as well as a tutorial tool.

15.
J Chem Phys ; 131(17): 174302, 2009 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-19895007

RESUMO

We present the structural, electronic, and optical properties of bimetallic Ag(n)Ni(n) (n

16.
J Chem Phys ; 129(19): 194108, 2008 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-19026046

RESUMO

We present a joint theoretical and experimental investigation of the absorption spectra of silver clusters Ag(n) (4

17.
Acta Paediatr ; 97(4): 425-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18363951

RESUMO

BACKGROUND: Midwives once used serial weighing to highlight lactation problems, but this is now discouraged for the fear of undermining maternal confidence. AIM: To explore weight changes in healthy newborn term babies, to gain information to aid interpretation of such measurements and to construct a centile chart for those exclusively breastfed during the first 2 weeks. METHOD: Two hundred ninety-nine mothers weighed their baby daily using the same electronic scales. In 46 cases, three or more consecutive measurements were omitted leaving 253 series to evaluate, of which 111 were exclusively breastfed. RESULTS: Breastfed babies lost a mean 6.4% of birthweight (95% CI: 5.5-7.3%) before starting to gain, and 54% took more than 8 days to regain birthweight. Artificially fed babies lost less (3.7%, 95% CI: 2.7-4.7%), but 39% had not regained their birthweight by 8 days. Once birthweight was regained, average gain was about 1% of birthweight per day in both breast- and artificially-fed babies. Measurements less than 5 days apart predicted average weight gain poorly. CONCLUSIONS: Feeding problems should be considered if weight is not increasing by 6 days, but some healthy babies take 17 days to regain their birthweight.


Assuntos
Aleitamento Materno , Aumento de Peso , Redução de Peso , Adulto , Feminino , Humanos , Recém-Nascido , Paridade , Gravidez , Fatores de Tempo
18.
J Phys Chem A ; 111(32): 7726-31, 2007 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-17637046

RESUMO

Theoretical study on the structure and electronic properties of small AgmNip (m + p < or = 6) clusters has been carried out in the framework of density functional theory. Structural features, cohesive energies, vertical ionization potentials, and charge transfers are evaluated for each Ag/Ni ratio. In all the AgmNip clusters, the nickel atoms are brought together, yielding a maximum of Ni-Ni bonds, and the silver atoms are located around a Ni core with a maximum of Ag-Ni bonds. The ionization potential and the highest occupied molecular orbital shape are directly related to the two- or three-dimensional character of the cluster's geometry. A very low electronic charge transfer from Ni to Ag is found, and the magnetic moment is located on Ni atoms but with a low spin polarization on silver in the Ni-rich clusters.

19.
Col. med. estado Táchira ; 15(3): 8-13, jul.-sept. 2006. graf
Artigo em Espanhol | LILACS | ID: lil-530757

RESUMO

El Embarazo Ectópico es la implantación del óvulo fecundado en un sitio diferente al endometrio. Se realizó un estudio retrospectivo, descriptivo y longitudinal, para conocer el comportamiento de algunas variables clínico-epidemiológicas relacionadas con el Embarazo Ectópico durante los años 2000-2005 en el Hospital Central de San Cristóbal “Dr. José María Vargas”. El estudio estuvo compuesto por 200 pacientes ingresadas con diagnóstico de Embarazo Ectópico. El antecedente ginecológico encontrado más frecuente fue aborto incompleto (34,5 por ciento) seguido del uso de dispositivos intrauterinos (12 por ciento). La clínica más llamativa fue el dolor abdominal (46 por ciento). El método paraclínico predominante la ecografía (75 por ciento). A la mayoría de las pacientes se les diagnóstico Embarazo Ectópico en su forma accidentada (95,93 por ciento) y localización ampollar (0,29 por ciento).


Assuntos
Humanos , Feminino , Gravidez , Dor Abdominal/diagnóstico , Gravidez Ectópica/diagnóstico , Gravidez Ectópica/epidemiologia , Gonadotropina Coriônica Humana Subunidade beta/análise , Progesterona/análise , Ultrassonografia , Ginecologia , Dispositivos Intrauterinos , Inflamação/etiologia , Obstetrícia , Venezuela/epidemiologia
20.
Arch Dis Child Fetal Neonatal Ed ; 89(4): F325-7, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15210667

RESUMO

AIMS: To assess the variation in blood pressure (BP) between limbs in normal neonates. To assess whether comparison of arm and leg BP in neonates is reproducible enough to allow the difference to raise suspicion of coarctation of the aorta. METHODS: Infants recruited from the postnatal wards and the postnatal murmur clinic underwent echocardiography and BP measurement in each limb using a Dinamap Compact T 482210. The method of BP measurement was guided by a telephone survey of 40 UK neonatal units. RESULTS: Forty healthy neonates underwent echocardiography and all had a normal aortic arch. BP was measured in 39. In three, BP in the arms was 20 mm Hg higher than in the legs. This gave a specificity of comparison of the upper and lower limb BPs of 92 (36/39) or a false positive rate of 8% (3/39). The standard deviation in BPs was 15.7 mm Hg between arms, 14.5 mm Hg between legs, and 11 mm Hg when the nearest arm and leg were compared. CONCLUSIONS: With current measurement techniques, normal neonates may have a wide variation in BP between limbs. A difference of 20 mm Hg in isolation is more likely to be due to random variability in measurement than to coarctation of the aorta. If coarctation of the aorta is suspected, it can only be excluded or confirmed by echocardiography.


Assuntos
Braço/fisiologia , Determinação da Pressão Arterial/normas , Pressão Sanguínea/fisiologia , Recém-Nascido/fisiologia , Perna (Membro)/fisiologia , Humanos , Reprodutibilidade dos Testes
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