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2.
Curr Microbiol ; 78(11): 3863-3871, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34508271

RESUMO

In previous in vitro studies, an inorganic additive (MCM3) showed a thermo-protective effect on the cell viability of Lacticaseibacillus rhamnosus CRL1505 (Lr-CRL1505). In this work, cultures of this probiotic strain were spray dried at lab scale using two carriers: maltodextrin (powder MA) and maltodextrin plus MCM3 (powder MA/MCM3). The cell survival was higher in powder MA/MCM3 (72.8%) than in powder MA (42.8%). Different rehydration media, including the additive MCM3, and two temperatures (37 °C and 45 °C) were evaluated. The best results were obtained in cells rehydrated at 37 °C in MCM3. During the storage of the powders, the highest cell counts were observed in the MA/MCM3 powder. Our results demonstrated that the presence of MCM3 in the carrier and in reconstitution media benefits the spray drying process and the recovery of dehydrated cells. Thus, the use of this additive of inorganic nature and low cost represents a promising technological alternative.


Assuntos
Probióticos , Meios de Cultura , Hidratação , Pós , Secagem por Atomização
3.
Sci Rep ; 11(1): 16467, 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34389759

RESUMO

We present a general qubit-boson interaction Hamiltonian that describes the Jaynes-Cummings model and its extensions as a single Hamiltonian class. Our model includes non-linear processes for both the free qubit and boson field as well as non-linear, multi-boson excitation exchange between them. It shows an underlying algebra with supersymmetric quantum mechanics features allowing an operator based diagonalization that simplifies the calculations of observables. As a practical example, we show the evolution of the population inversion and the boson quadratures for an initial state consisting of the qubit in the ground state interacting with a coherent field for a selection of cases covering the standard Jaynes-Cummings model and some of its extensions including Stark shift, Kerr-like, intensity dependent coupling, multi-boson exchange and algebraic deformations.

4.
Rev Gastroenterol Mex (Engl Ed) ; 86(2): 133-139, 2021.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33752942

RESUMO

INTRODUCTION: Clinical practice guidelines on the diagnosis and treatment of acute pancreatitis (CPGDTAP) have been designed in an effort to reduce the morbidity and mortality of that severe disease. AIM: To identify the knowledge acquired from CPGDTAP in hospitals in Veracruz. MATERIALS AND METHODS: A descriptive, observational, multicenter study was conducted at four hospitals in Veracruz, through the application of a survey to evaluate the knowledge of attending physicians and residents that treat patients with acute pancreatitis. Descriptive statistics were employed to analyze the results. RESULTS: A total of 74 physicians were surveyed: 55.41% of whom were attending physicians and 44.59% of whom were resident physicians. The majority of physicians (67.57%) were familiar with CPGDTAP from the Asociación Mexicana de Gastroenterología (AMG), followed by those of the General Health Council of the Mexican Department of Health (CENETEC, the Spanish acronym) (54.05%) and the American College of Gastroenterology (ACG) (48.65%). A total of 97.30% of the physicians routinely use a nasogastric tube, 79.73% considered early enteral nutrition to be very important, as did 98.65% regarding generous fluid replacement, 85.14% did not routinely use antimicrobials, 63.51% ordered a CAT scan at 72h or later, and 87.84% answered that infected necrosis was the indication for surgery, preferably after the third week. DISCUSSION AND CONCLUSIONS: In our hospital environment, the CPGDTAP issued by the AMG and CENETEC were the most well-known, but their recommended measures were given importance by under 85% of the physicians surveyed. Therefore, the diffusion of the knowledge they contain is advisable to guarantee optimal results in acute pancreatitis management.

5.
J Dairy Sci ; 104(5): 5229-5238, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33685676

RESUMO

Enterohemorrhagic Escherichia coli (EHEC) O157:H7 is a major etiologic agent that causes bloody diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome (HUS). Shiga toxin (Stx) is the main virulence factor of EHEC responsible for the progression to HUS. Although many laboratories have made efforts to develop an effective treatment for Stx-mediated HUS, a specific therapy has not been found yet. Human consumption of bovine colostrum is known to have therapeutic effects against several gastrointestinal infections because of the peptide and proteins (including antibodies) with direct antimicrobial and endotoxin-neutralizing effects contained in this fluid. We have previously demonstrated that colostrum from Stx type 2 (Stx2)-immunized pregnant cows effectively prevents Stx2 cytotoxicity and EHEC O157:H7 pathogenicity. In this study we evaluated the preservation of the protective properties of hyperimmune colostrum against Stx2 (HIC-Stx2) after pasteurization and spray-drying processes by performing in vitro and in vivo assays. Our results showed that reconstituted HIC-Stx2 colostrum after pasteurization at 60°C for 60 min and spray-dried under optimized conditions preserved specific IgG that successfully neutralized Stx2 cytotoxicity on Vero cells. Furthermore, this pasteurized/dehydrated and reconstituted HIC-Stx2 preserved the protective capacity against EHEC infection in a weaned mice model. The consumption of hyperimmune HIC-Stx2 bovine colostrum could be effective for HUS prevention in humans as well as in EHEC control in calves. However, further studies need to be done to consider its use for controlling EHEC infections.


Assuntos
Doenças dos Bovinos , Escherichia coli Êntero-Hemorrágica , Infecções por Escherichia coli , Animais , Bovinos , Doenças dos Bovinos/prevenção & controle , Chlorocebus aethiops , Colostro , Infecções por Escherichia coli/prevenção & controle , Infecções por Escherichia coli/veterinária , Feminino , Pasteurização , Gravidez , Células Vero , Virulência
6.
Rev Gastroenterol Mex (Engl Ed) ; 86(1): 28-35, 2021.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32345507

RESUMO

INTRODUCTION: Cirrhosis of the liver is a serious public health problem worldwide, with regional variations determined by cultural factors and economic development. AIM: To know the characteristics of the social, cultural, and economic factors of the patients with cirrhosis of the liver in Veracruz. MATERIALS AND METHODS: A multicenter, retrolective, relational research study was conducted on patients with cirrhosis of the liver at five healthcare institutions in Veracruz. The variables analyzed were etiology, age, sex, civil status, educational level, occupation, and income. Descriptive and inferential statistics were utilized, and statistical significance was set at a P<.05. The Windows IBM-SPSS version 25.0 program was employed. RESULTS: A total of 182 case records of patients with cirrhosis of the liver were included. The etiologic factors were chronic alcohol consumption (47.8%), viral disease (28.5%), nonalcoholic fatty liver disease (NAFLD) (8.79%), autoimmune liver disease (4.4%), cholestasis (1.64%), and cryptogenic liver disease (8.8%). Mean patient age was 66.14±13.91, with a predominance of men (58.79%). In comparing the socioeconomic and cultural factors related to etiology, secondary and tertiary education and singleness were statistically significant in male alcoholics (P<.05), viral diseases and NAFLD were significantly associated with women with no income (P<.05), cryptogenic liver disease was significantly associated with women (P<.05), and cholestasis and autoimmune liver disease were not significantly associated with any of the factors. CONCLUSIONS: The study results revealed the influence of socioeconomic and cultural factors related to the different causes of cirrhosis of the liver in our environment.

7.
BMC Nephrol ; 19(1): 89, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29665795

RESUMO

BACKGROUND: Removal of uraemic toxins is inadequate using current dialysis strategies. A new class of dialysis membranes have been developed that allow clearance of larger middle molecules. The REMOVAL-HD study (a tRial Evaluating Mid cut-Off Value membrane clearance of Albumin and Light chains in HaemoDialysis patients) will address safety, efficacy and the impact on patient-centred outcomes with the use of a mid cut-off (MCO) dialyser in a chronic haemodialysis (HD) population. METHODS: REMOVAL-HD is an open label, prospective, non-randomised, single-arm, multi-centre device study in 85 chronic HD participants. All visits will be conducted during regular HD sessions and participants will undergo a 1 month wash-in period using a standardised high flux dialyser, 6 months of intervention with a MCO dialyser and 1 month of wash-out using a high flux dialyser. The primary endpoint is change in pre-dialysis concentrations of serum albumin, with secondary endpoints including the efficacy of clearance of free light chains and ß-2 microglobulin, and patient-centred outcomes including quality of life, symptom burden, functional status, nutritional status, hospitalisation and death. DISCUSSION: MCO dialysers are a novel form of HD membrane. The REMOVAL-HD study is a pivotal study designed to monitor the immediate and medium-term effects following exposure to this dialyser. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry Number (ANZCTRN) 12616000804482 . Date of registration - 21/06/2016.


Assuntos
Cadeias lambda de Imunoglobulina/sangue , Membranas Artificiais , Diálise Renal/instrumentação , Insuficiência Renal Crônica/terapia , Projetos de Pesquisa , Albumina Sérica/metabolismo , Adulto , Efeitos Psicossociais da Doença , Hospitalização , Humanos , Estado Nutricional , Avaliação de Resultados da Assistência ao Paciente , Estudos Prospectivos , Qualidade de Vida , Diálise Renal/efeitos adversos , Diálise Renal/métodos , Insuficiência Renal Crônica/sangue , Análise de Sobrevida , Microglobulina beta-2/sangue
9.
Lett Appl Microbiol ; 62(2): 160-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26551056

RESUMO

UNLABELLED: The aim of this manuscript was to study the influence of water activity (aW ) and pH in the ecophysiological behaviour of Aspergillus fumigatus strains at human body temperature. In addition, gliotoxin production and enzymatic ability among environmental (n = 2) and clinical (n = 5) strains were compared. Ecophysiological study of environmental strains was performed on agar silage incubated at 37°C, studying the interaction at eight aW levels (0·8, 0·85, 0·9, 0·92, 0·94, 0·96, 0·98 and 0·99) and eight pH levels (3·5, 4, 4·5, 5, 6, 7, 7·5 and 8). Considering the influence of the assumed lung conditions on growth of A. fumigatus (aW 0·98/0·99 and pH of 7/7·5), the optimal condition for the development of A. fumigatus RC031 was at aW 0·99 at pH 7. At aW 0·98/0·99 and pH of 7/7·5, the highest growth rate and the lowest lag phase was reported, whereas there were no significant differences at aW 0·98/0·99 and pH 7/7·5 interactions on growth of A. fumigatus RC032. Gliotoxin production of A. fumigatus strains was evaluated. The gliotoxin production was similar in clinical and environmental strains. Elastin activity was studied in solid medium, highest elastase activity index was found for clinical strain A. fumigatus RC0676, followed by the environmental strain A. fumigatus RC031. Opportunistic environmental strains can be considered as pathogenic in some cases when rural workers are exposed constantly to handling silage. SIGNIFICANCE AND IMPACT OF THE STUDY: Aspergillus fumigatus is one of the main opportunist pathogen agents causing invasive aspergillosis. Rural workers present a constant exposition to A. fumigatus spores caused by feed-borne manipulation. In this study, environmental A. fumigatus strains were able to grow and produce gliotoxin onto the studied conditions including the lung ones. Environmental and clinical strains were physiologically similar and could be an important putative infection source in rural workers.


Assuntos
Aspergillus fumigatus/enzimologia , Aspergillus fumigatus/metabolismo , Elastina/metabolismo , Gliotoxina/biossíntese , Silagem/microbiologia , Aspergilose/microbiologia , Aspergilose/patologia , Aspergillus fumigatus/fisiologia , Humanos
10.
Artigo em Inglês | MEDLINE | ID: mdl-25599419

RESUMO

Environmental conditions play a key role in fungal development. During the silage production process, humidity, oxygen availability and pH vary among lactic-fermentation phases and among different silage sections. The aim of this work was to study the physiological behaviour of gliotoxicogenic Aspergillus fumigatus strains isolated from maize silage under simulated natural physicochemical conditions - different water activities (a(W)), temperatures (Tº), pH and oxygen pressure - on the growth parameters (growth rate and lag phase) and gliotoxin production. The silage was made with the harvested whole maize plant that was chopped and used for trench-type silo fabrication. Water activity and pH of the silage samples were determined. Total fungal counts were performed on Dichloran Rose Bengal Chloramphenicol agar and Dichloran 18% Glycerol agar. The morphological identification of A. fumigatus was performed with different culture media and at different growth temperature to observe microscopic and macroscopic characteristics. Gliotoxin production by A. fumigatus was determined by HPLC. All strains isolated were morphologically identified as A. fumigatus. Two A. fumigatus strains isolated from the silage samples were selected for the ecophysiological study (A. fumigatus sensu stricto RC031 and RC032). The results of this investigation showed that the fungus grows in the simulated natural physicochemical conditions of corn silage and produces gliotoxin. The study of the physiological behaviour of gliotoxigenic A. fumigatus under simulated environmental conditions allowed its behaviour to be predicted in silage and this will in future enable appropriate control strategies to be developed to prevent the spread of this fungus and toxin production that leads to impairment and reduced quality of silage.


Assuntos
Aspergillus fumigatus/química , Aspergillus fumigatus/isolamento & purificação , Gliotoxina/análise , Silagem/microbiologia , Zea mays/microbiologia , Aspergillus fumigatus/metabolismo , Físico-Química , Gliotoxina/biossíntese , Zea mays/metabolismo
11.
ScientificWorldJournal ; 2013: 402196, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23843734

RESUMO

This paper presents the next step in the evolution of multi-sensor wireless network systems in the early automatic detection of forest fires. This network allows remote monitoring of each of the locations as well as communication between each of the sensors and with the control stations. The result is an increased coverage area, with quicker and safer responses. To determine the presence of a forest wildfire, the system employs decision fusion in thermal imaging, which can exploit various expected characteristics of a real fire, including short-term persistence and long-term increases over time. Results from testing in the laboratory and in a real environment are presented to authenticate and verify the accuracy of the operation of the proposed system. The system performance is gauged by the number of alarms and the time to the first alarm (corresponding to a real fire), for different probability of false alarm (PFA). The necessity of including decision fusion is thereby demonstrated.


Assuntos
Redes de Comunicação de Computadores/instrumentação , Monitoramento Ambiental/instrumentação , Incêndios , Interpretação de Imagem Assistida por Computador/instrumentação , Termografia/instrumentação , Transdutores , Tecnologia sem Fio/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Raios Infravermelhos
12.
Arch. alerg. inmunol. clin ; 44(1): 7-13, 2013. tab
Artigo em Espanhol | LILACS | ID: biblio-947417

RESUMO

Las proteínas de superficie del merozoíto (MSP) son de importancia en la invasión parasitaria al glóbulo rojo. La proteína MSP-5, encontrada en merozoítos libres, tiene un papel en la inmunización de ratones al P. falciparum y P. yoelii, pese a lo cual algunos estudios cuestionan su rol en la invasión. La proteína MSP-6 forma junto con MSP-1 y MSP-7 un complejo en la superficie del merozoíto, liberado del parásito cerca del momento de la invasión al glóbulo rojo. Con el fin de predecir el fenómeno de unión de péptidos de las proteínas de superficie MSP-5 y MSP-6, se aplicó una teoría de unión al HLA clase II, a la totalidad de secuencias de 20 aminoácidos de tales moléculas. Se calcularon los valores de probabilidad, combinatoria y entropía de 168 secuencias nonámeras sobrelapadas de la proteína MSP-5 y 228 de MSP-6. Por último se aplicó la teoría de unión a todos los péptidos nonámeros de tres proteínas construidas computacionalmente, cada una con una longitud de 500 aminoácidos. Para la proteína MSP-5 se predijo un total de 31 secuencias asociadas al macroestado de unión y 137 al de no unión, mientras que se predijo la existencia de 35 secuencias asociadas al macroestado de unión para MSP-6 y 193 al de no unión. Se encontraron respectivamente 100, 111 y 91 secuencias predichas de unión para las tres proteínas teóricas construidas. La predicción teórica de unión de péptidos es útil para facilitar el desarrollo de vacunas, al evidenciar el orden físico-matemático subyacente al fenómeno.(AU)


Assuntos
Humanos , Teoria da Probabilidade , Proteína 1 de Superfície de Merozoito , Merozoítos , Peptídeos , Vacinas , Entropia
13.
J Phys Condens Matter ; 24(27): 276001, 2012 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-22713475

RESUMO

Ferrous antimonite, FeSb(2)O(4), which is isostructural with Pb(3)O(4), and some lead- and cobalt-doped variants of composition FeSb(1.5)Pb(0.5)O(4) and Co(0.5)Fe(0.5)Sb(1.5)Pb(0.5)O(4) have been examined by (57)Fe and (121)Sb Mössbauer spectroscopy. Antimony is present as Sb(3+). The presence of Pb(2+) on the antimony site induces partial oxidation of Fe(2+) to Fe(3+). There is no Verwey-type transition in which electrons are shared between iron in different oxidation states. The quasi-one-dimensional magnetic structure gives rise to situations in which weakly coupled Fe(2+) ions can coexist in a non-magnetic state alongside Fe(3+) ions in a magnetically ordered state.


Assuntos
Antimônio/química , Ferro/química , Chumbo/química , Magnetismo , Teste de Materiais , Modelos Químicos , Espectroscopia de Mossbauer
14.
J Nanosci Nanotechnol ; 12(12): 9148-55, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23447970

RESUMO

The growth of Anatase nanostructured films using dc reactive magnetron sputtering and post-annealing treatment is reported. TiO2 has been deposited on Porous Anodic Alumina Films used as templates which were previously grown in phosphoric acid solution and etched to modify their pore diameters. This synthesis via results in the formation of vertically aligned and spatially ordered TiO2 nanostructures replicating the underlying template. Previously, the growth optimization of TiO2 thin films deposited by dc magnetron sputtering on flat silicon substrates was done. The crystalline structure and Ti in-depth concentration profile were determined by grazing incidence X-ray diffraction and Rutherford backscattering spectrometry, respectively. The surface morphology of the samples was explored by mean of a Field Emission Gun scanning electron microscope. Optical properties of the nanostructured samples were studied by using the reflectance spectra received in the UV-visible range. In these spectra different band gap values and complex light absorption features were observed.

15.
Curr Med Chem ; 18(31): 4761-85, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21919849

RESUMO

Chromenopyridines constitute a structurally diverse class of compounds with a wide range of bioactivities and increasing presence in drugs. Here we analyze the scope of the synthetic methodology to access this nucleus with emphasis on multicomponent reactions and robust methodologies. Reactivity issues, medicinal applications and other properties are also reviewed.


Assuntos
Piridinas/química , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Bactérias/efeitos dos fármacos , Benzopiranos/química , Humanos , Compostos Organometálicos/química , Fosfinas/química , Piridinas/síntese química , Piridinas/farmacologia
16.
Anal Chim Acta ; 699(1): 33-43, 2011 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-21704755

RESUMO

Cyclic voltammetry (CV) is a very useful electrochemical tool used to study reaction systems that include chemical steps that are coupled to electron transfers. This type of system generally involves the chemical reaction of an electrochemically generated free radical. Published methods exist that are used to determine the kinetics of electrochemically initiated chemical reactions from the measurements of the peak current ratio (i(pa)/i(pc)) of a cyclic voltammogram. The published method requires working curves to relate a kinetic parameter to the peak current ratio. In the presented work, a digital simulation package was used to obtain improved working curves for specific working conditions. The curves were compared with the published results for the first- and second-order chemical reactions following the charge transfer step mechanisms. According to the presented results, the previously published working curve is reliable for a mechanism with a first-order chemical reaction; however, a change in the switching potential requires a recalculation of the curve. In the case of mechanisms with a second-order step (dimerisation and disproportionation), several different views exist on how the second-order chemical term should be expressed so that different values of the constant are obtained. Parameters such as electrode type, electrode area, electroactive species concentration, switching potential, scan rate and method for peak current ratio calculation modify the working curves and must always be specified. We propose a standardised method to obtain the most reliable kinetic constant values. The results of this work will permit researchers who handle simulation software to construct their own working curves. Additionally, those who do not have the simulation software could use the working curves described here. The revelations of the presented experiments may be useful to a broad chemistry audience because this study presents a simple and low-cost procedure for the study of free radicals that otherwise should be studied with more sophisticated and expensive techniques, such as ESR or pulse radiolysis.


Assuntos
Técnicas Eletroquímicas/métodos , Algoritmos , Eletrodos , Transporte de Elétrons , Cinética , Software
17.
Biochem Biophys Res Commun ; 393(4): 649-55, 2010 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-20153731

RESUMO

Gold nanoparticles (GNPs) offer a great promise in biomedicine. Currently, there is no data available regarding the accumulation of nanoparticles in vivo after repeated administration. The purpose of the present study was to evaluate the bioaccumulation and toxic effects of different doses (40, 200, and 400 microg/kg/day) of 12.5 nm GNPs upon intraperitoneal administration in mice every day for 8 days. The gold levels in blood did not increase with the dose administered, whereas in all the organs examined there was a proportional increase on gold, indicating efficient tissue uptake. Although brain was the organ containing the lowest quantity of injected GNPs, our data suggest that GNPs are able to cross the blood-brain barrier and accumulate in the neural tissue. Importantly, no evidence of toxicity was observed in any of the diverse studies performed, including survival, behavior, animal weight, organ morphology, blood biochemistry and tissue histology. The results indicate that tissue accumulation pattern of GNPs depend on the doses administered and the accumulation of the particles does not produce sub-acute physiological damage.


Assuntos
Ouro/farmacocinética , Ouro/toxicidade , Nanopartículas Metálicas/toxicidade , Animais , Ouro/administração & dosagem , Masculino , Nanopartículas Metálicas/administração & dosagem , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Tecidual
18.
Phys Rev Lett ; 103(15): 157401, 2009 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-19905665

RESUMO

We investigated magnetoelastic coupling through the field-driven transition to the fully polarized magnetic state in quasi-two-dimensional [Cu(HF2)(pyz)2]BF4 by magnetoinfrared spectroscopy. This transition modifies out-of-plane ring distortion and bending vibrational modes of the pyrazine ligand. The extent of these distortions increases with the field, systematically tracking the low-temperature magnetization. These distortions weaken the antiferromagnetic spin exchange, a finding that provides important insight into magnetic transitions in other copper halides.

19.
Talanta ; 75(3): 691-6, 2008 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-18585133

RESUMO

Finasteride in hydroalcoholic solutions (ethanol/Britton-Robinson buffer, 30/70) exhibits cathodic response in a wide range of pH (-0.5 to 12) using differential pulse (DPP) and test polarography (TP). The reduction peak of finasteride at acidic pH, is a catalytic proton peak resulting from a mechanism involving a first protonation of finasteride followed by the reduction of the protons combined with finasteride in order to regenerate finasteride and liberate hydrogen. Based on the catalytic hydrogen wave, a novel method for the determination of finasteride can be proposed. For analytical purposes we selected DPP technique in an ethanol/0.0625 mol L(-1) H(2)SO(4) (30/70) solution medium. In this condition the I(p) varied linearly with finasteride concentration between 5 x 10(-5) and 5 x 10(-4) mol L(-1). Within-day and inter-day reproducibility's were adequate with R.S.D. values lower than 2%. The selectivity of the method was checked with both accelerated degradation trials and typical excipients formulations. The developed method was applied to the assay and the uniformity content of finasteride tablets and compared with the standard HPLC method. The DPP-developed method was adequate for the finasteride determination in pharmaceutical forms as that exhibited an adequate accuracy, reproducibility and selectivity. Furthermore, treatment of the sample was not required as in HPLC; the method is not time-consuming and less expensive than the HPLC ones.


Assuntos
Finasterida/análise , Cromatografia Líquida de Alta Pressão/métodos , Eletroquímica , Eletrodos , Inibidores Enzimáticos/química , Finasterida/química , Mercúrio/química , Estrutura Molecular , Oxirredução , Reprodutibilidade dos Testes , Comprimidos/química , Fatores de Tempo
20.
Phys Rev Lett ; 100(17): 177205, 2008 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-18518332

RESUMO

Application of a magnetic field offers an incisive opportunity to tune competing interactions in complex materials. Here we probe field-induced changes in the local structure of DyMn2O5 by using magnetoinfrared spectroscopy. The high tunability of the dielectric constant and ferroelectric polarization with field is well documented in the literature, but the lattice response on the microscopic level remains unknown. In this work, we reveal the dynamic nature of the local structural response to field and analyze it in terms of calculated mode displacements and local lattice distortions.

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