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2.
J Adolesc ; 36(6): 1077-81, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24215954

RESUMO

The objective of this study was to develop a questionnaire to assess child-to-parent aggression in adolescents and to document the extent of the problem. The questionnaire developed in this study, the Child-to-Parent Aggression Questionnaire (CPAQ), includes forms of physical and psychological aggression directed at both the mother and the father. It also includes open questions about the reasons for the aggressive acts. The CPAQ was completed by a sample of 2719 adolescents (age range: 13-18 years old, 51.4% girls). Confirmatory factor analysis supported a four-factor correlated structure (physical aggression against mother, physical aggression against father, psychological aggression against mother, and psychological aggression against father). Psychological and physical aggression against the mother was more frequent than against the father. However, there were no differences with regard to severe forms of aggression. Girls scored significantly higher on all indicators of psychological aggression, including severe psychological aggression. Nevertheless, except for the prevalence of physical aggression against mothers, which was higher in females, there were no significant differences in physical aggression against parents. Finally, the reasons provided by the adolescents for the aggression included both instrumental (e.g., to obtain permission to get home late and to access their computers) and reactive reasons (e.g., anger and self-defense). These findings highlight the complexity of child-to-parent aggression in adolescence.


Assuntos
Comportamento do Adolescente/psicologia , Agressão/psicologia , Relações Pais-Filho , Inquéritos e Questionários , Adolescente , Análise Fatorial , Feminino , Humanos , Masculino , Psicometria , Reprodutibilidade dos Testes , Espanha
3.
Bioresour Technol ; 111: 460-7, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22386201

RESUMO

A non-wood raw material with high potential for pulp and paper applications (Hesperaloe funifera) was subjected to a steam explosion pre-treatment, and the subsequent effect of this pretreatment on biopulping and biobleaching was studied. An increase in the delignification rate, bigger than that reported for autohydrolysis and acid hydrolysis pre-treatments, and a reduction in chemical consumption were found during kraft pulping of the exploded samples. However, biopulping with the laccase-mediator system (LMS) did not lead to a reduction in the kappa number in either non-exploded or exploded unbleached pulps. On the other hand, the steam explosion pretreatment boosted the advantages of the LMS pre-treatment (decrease in kappa number and increase in brightness) favored biobleaching, with a 53.1% delignification rate and a final brightness of 67% ISO. Finally, the steam explosion pre-treatment also improved the color properties of the bleached pulp and reduced the hydrogen peroxide consumption by 24.6%.


Assuntos
Asparagaceae/química , Enzimas/química , Hidrólise
4.
Bioresour Technol ; 110: 371-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22349193

RESUMO

Laccase and xylanase were tested for their suitability for biobleaching of soda-anthraquinone pulp from oil palm empty fruit bunches (EFB). An enzymatic stage with xylanase (X) and/or laccase (L) was incorporated before the alkaline extraction stage (E) and the hydrogen peroxide bleaching stage (P). Compared with controls, the LEP sequence resulted in an improvement of optical properties (brightness and colorimetric properties) and a reduction of the kappa number. When xylanase and laccase were used jointly, no improvement was detected, however, when the xylanase application preceded the laccase stage, the beneficial effects of laccase were boosted. Thus, the final XLEP bleached pulp showed a kappa number of 5.4 and a brightness of 60.5% ISO, although the hydrogen peroxide consumption increased (77.0% vs. 64.5% and 73.8% for EP and LEP respectively). Finally, after subjecting the bleached pulps to accelerated ageing, the best optical properties were observed in the XLEP pulp.


Assuntos
Cor , Eucalyptus/metabolismo , Lacase/metabolismo , Xilosidases/metabolismo , Antraquinonas/metabolismo
5.
Bioresour Technol ; 102(14): 7183-9, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21570827

RESUMO

The effect of a pretreatment consisting of steam explosion (SE) followed by a laccase mediator system (LMS) stage on Eucalyptus globulus kraft pulping has been evaluated and compared with fungal pretreatments. Pretreatment with SE and LMS was more efficient than pretreatments using Pycnoporus sanguineus and Trametes sp. I-62. Steam explosion not only improved the enzyme penetration into the wood chips and shortened the pulping process by 60%, but also extracted around 50% of the hemicelluloses which could be converted into value-added products. The optimal conditions for the LMS treatment were 3h, 3UA/g and 40°C. Compared to SE, the SE/LMS treatment yielded an increase in delignification of 13.9% without affecting pulp properties, provided a similar screened kraft yield, and reduced consumption of chemical reagents Na(2)S and NaOH by 11.5% and 6.3%, respectively. Therefore, SE/LMS is a promising pretreatment for converting the pulp mill into a forest bio-refinery.


Assuntos
Biotecnologia/métodos , Eucalyptus/química , Lacase/metabolismo , Papel , Vapor , Aspergillus/enzimologia , Fenômenos Ópticos , Pycnoporus/fisiologia , Hidróxido de Sódio/análise , Sulfetos/análise , Trametes/fisiologia
6.
Bioresour Technol ; 102(6): 4530-5, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21256741

RESUMO

The aim of this work was to evaluate the response to biobleaching of steam exploded kraft pulps and to compare the results with the controls. For this end, a laccase-mediator treatment using commercial laccase (Novozyme 51003) and a natural mediator (acetosyringone) were assayed, followed by alkaline extraction and hydrogen peroxide stages. Our approach resulted in exploded biobleached pulps with lower kappa number and improved optical properties compared to controls, even after subjecting pulps to accelerated ageing. Additionally, use of hydrogen peroxide was reduced. The LMS (laccase-mediator system) had a smaller impact on the properties of the bleached pulps and on hydrogen peroxide consumption than the steam explosion process did.


Assuntos
Biotecnologia/métodos , Eucalyptus/metabolismo , Papel , Vapor , Madeira/química , Álcalis/química , Peróxido de Hidrogênio/química , Lacase/metabolismo , Fatores de Tempo , Viscosidade
7.
Bioresour Technol ; 101(6): 1866-70, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19857961

RESUMO

The aim of this work was to obtain a LMS pre-treatment applicable to industrial TCF bleaching. Kraft pulp from Eucalyptus globulus was treated at 40 degrees C/pH 3 and 60 degrees C/pH 5 for 1h using an extracellular fluid enriched in laccase produced by Pycnoporus sanguineus and acetosyringone as mediator (HBT was used as a control mediator) (L). Alkaline extraction (E) and hydrogen peroxide (P) stages were then assayed. The LEP alternative was an efficient sequence to bleach kraft pulp since the enzymatic pre-treatment boosted the subsequent chemical bleaching. The best L pre-treatment was obtained with laccase-acetosyringone at 40 degrees C/pH 3. It reduces kappa number and hexenuronic acids, increases pulp viscosity, lowers hydrogen peroxide consumption down to an 87.4% (94.0% without L) and enhances brightness up to a 59% ISO (51% ISO without L).


Assuntos
Biotecnologia/métodos , Pycnoporus/metabolismo , Acetofenonas/química , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Resíduos Industriais , Lacase/química , Luz , Oxidantes/química , Papel , Temperatura , Fatores de Tempo , Eliminação de Resíduos Líquidos/métodos
8.
Metabolism ; 48(3): 390-4, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10094119

RESUMO

We examined the effect of acute exercise and reduced cortisol on pituitary and adrenal responsiveness and the impact of reduced plasma cortisol on maximal oxygen consumption (VO2max) in eight trained (T) and eight untrained (UT) males. Subjects completed two graded maximal exercise tests (GXT), each preceded by either overnight metyrapone (MET) or placebo (PLA) administration. Blood samples were collected before and after GXT. With PLA, resting corticotropin (ACTH) levels were higher in T versus UT men; however, cortisol and 11-deoxycortisol were similar between groups. Following GXT on PLA, cortisol was unchanged but 11-deoxycortisol increased in both groups; however, ACTH increased only in UT men. For both groups, cortisol, 11-deoxycortisol, and ACTH were different post-GXT with MET versus PLA. Furthermore, following GXT with MET, the ACTH response was greater in T versus UT subjects. VO2max was not altered by MET in either group. We conclude that (1) at rest, only ACTH levels differed between T and UT men; (2) individually, the GXT and MET provide a similar ACTH response in UT but not in T subjects; (3) when GXT and MET are superimposed, they provide a stronger stimulus to pituitary and adrenal reserve than either test alone; (4) the combination of MET and GXT elicits a greater ACTH response in T compared with UT men; and (5) an acute reduction in plasma cortisol does not alter VO2max.


Assuntos
Hormônio Adrenocorticotrópico/sangue , Exercício Físico/fisiologia , Hidrocortisona/fisiologia , Aptidão Física/fisiologia , Adulto , Teste de Esforço , Antagonistas de Hormônios/farmacologia , Humanos , Hidrocortisona/antagonistas & inibidores , Hidrocortisona/sangue , Masculino , Metirapona/farmacologia , Consumo de Oxigênio/fisiologia , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/metabolismo
9.
Rev Enferm ; 22(12): 882-4, 1999 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-10797774

RESUMO

The authors discuss treatment provided to children suffering from Acquired Immunodeficiency Syndrome (AIDS) and to their families. By means of checking the nursing files for hospitalized children, the authors observe alterations and omissions which are common to other diseases, plus those which are specifically related to this disease: psychosocial problems. A treatment plan and an assistance procedure are drawn up. In these, the role the family plays to support the patient as well as that of the multidisciplinary team are emphasized.


Assuntos
Síndrome da Imunodeficiência Adquirida/enfermagem , Criança Hospitalizada , Planejamento de Assistência ao Paciente , Enfermagem Pediátrica/métodos , Síndrome da Imunodeficiência Adquirida/psicologia , Fatores Etários , Criança , Criança Hospitalizada/psicologia , Pré-Escolar , Feminino , Humanos , Masculino , Auditoria de Enfermagem , Pesquisa em Avaliação de Enfermagem , Pais/educação , Pais/psicologia
10.
Int J Sports Med ; 14(6): 334-8, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8407064

RESUMO

The purpose of this study was to characterize the aerobic and anaerobic capabilities of United States Cycling Federation cyclists in different categories. To determine aerobic and anaerobic power, 38 competitive road cyclists (32 males, 6 females) performed a VO2max test and a Wingate anaerobic test, respectively. Male cyclists in category II had the highest VO2max, both in absolute and relative terms. Their VO2max was 6% and 10% higher than category III and IV cyclists, respectively (4.98 +/- 0.14 vs 4.72 +/- 0.15 vs 4.54 +/- 0.12 l/min). A significant difference existed between category II and IV male cyclists (p < 0.05). VO2max for female cyclists (3.37 +/- 0.13 l/min) was significantly (p < 0.05) lower than those for males. The Wingate anaerobic test revealed that male cyclists in category II also had the highest anaerobic power output. The peak power output in category II, III and IV was 13.86 +/- 0.23, 13.55 +/- 0.25, and 12.80 +/- 0.41 W/kg, respectively. The mean power output in category II, III, and IV was 11.22 +/- 0.18, 11.06 +/- 0.15, and 10.40 +/- 0.30 W/kg, respectively. The difference in the mean power output between category II and IV was significant (p < 0.05). Female cyclists recorded significantly less peak and mean power output than their male counterparts (p < 0.05). However, when expressed relative to lean body mass, anaerobic power was similar for both sexes. No inter-correlation was found in any measurement between the aerobic and anaerobic power values. On the whole, category II male cyclists were characterized by higher aerobic and anaerobic power outputs.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Limiar Anaeróbio/fisiologia , Ciclismo/fisiologia , Músculos/fisiologia , Consumo de Oxigênio/fisiologia , Adulto , Aerobiose , Anaerobiose , Ciclismo/classificação , Composição Corporal , Teste de Esforço , Fadiga/metabolismo , Fadiga/fisiopatologia , Feminino , Humanos , Masculino , Músculos/metabolismo , Aptidão Física , Fatores Sexuais , Espirometria , Estresse Mecânico , Estados Unidos
11.
J Appl Physiol (1985) ; 70(4): 1816-20, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2055859

RESUMO

The purpose of this study was to compare the rate of decline in blood lactate (La) levels in nine trained men [maximal O2 consumption (VO2max) 65.5 +/- 3.3 ml.kg-1.min-1] and eight untrained men (VO2max 42.2 +/- 2.8 ml.kg-1.min-1) during passive recovery from a 3-min exercise bout. Trained and untrained subjects cycled at 85 and 80% VO2max, respectively, to produce similar peak blood La concentrations. Twenty samples of arterialized venous blood were drawn from a heated hand vein during 60 min of recovery and analyzed in an automated La analyzer. The data were then fitted to a biexponential function, which closely described the observed data (r = 0.97-0.98). There was no difference in the coefficient expressing the rate of decline in blood La for trained and untrained groups (0.0587 +/- 0.0111 vs. 0.0579 +/- 0.0100, respectively). However, trained subjects demonstrated a faster time-to-peak La (P = 0.01), indicative of a faster efflux of La from muscle to blood. Thus the rate of decline in blood La after exercise does not appear to be affected by training. The faster decline previously reported for trained subjects may be due to the use of a linear rather than a biexponential curve fit.


Assuntos
Exercício Físico/fisiologia , Lactatos/sangue , Resistência Física/fisiologia , Adolescente , Adulto , Humanos , Cinética , Lactatos/metabolismo , Ácido Láctico , Masculino , Músculos/metabolismo , Educação Física e Treinamento
12.
Rev. cuba. hematol. inmunol. hemoter ; 1(1): 37-42, ene.- abr. 1985.
Artigo em Espanhol | CUMED | ID: cum-7100

RESUMO

Se presentan los resultados de los estudios de glucosa 6 fosfato deshidrogenasa (G6PD) realizados en Cuba en individuos aparentemente sanos y en pacientes con anemia hemolítica congénita no esferocítica (AHCNE) y/o episodios hemolíticos inducidos por agentes oxidantes o procesos infecciosos. Se pudo concluir que la G6PD es polimórfica en nuestra población con una frecuencia de 86 para la G6PD B, 7 para la G6PD A y 5 para la G6PD A-, así como el íctero del recién nacido es una de las formas clínicas de la deficiencia de G6PD más frecuentes en Cuba. Se muestran los resultados del estudio bioquímico realizado a 10 variantes nuevas encontradas en nuestra población (AU)


Assuntos
Cuba , Deficiência de Glucosefosfato Desidrogenase/enzimologia , Anemia Hemolítica Congênita
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