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Journal of Radioanalytical and Nuclear Chemistry
Authors:
J. Santana Romero
,
F. Martínez Luzardo
,
E. Codorniú Hernández
,
L. Vargas Guerra
,
P. Melo Cala
,
M. García Guillén
,
K. Isaac Olivé
,
P. Estevez
,
A. Roque Córdoba
, and
M. Benítez

Abstract  

Vegetable tannins are polyphenolic plants secondary metabolites, widely distributed in all parts of trees and herbs. The role of these substances in many metabolic processes is very important. Vegetable tannins have been implicated as probable antinutritional factors, decreasing the assimilation of diet protein assimilation by cattle. On the other hand, protective antioxidant and antimutagenic properties have been ascribed for these compounds. Characterization of vegetable tannins is important in order to find new sources of natural raw materials with medical and pharmaceutical applications. Protein precipitation capacity as a function of pH, competitive protein and ADN binding assays and the determination of tannins concentration are described. Radioisotope labeled protein and tannins were used in all of the determinations.

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Journal of Thermal Analysis and Calorimetry
Authors:
J. Botelho
,
A. Souza
,
L. Nunes
,
A. Chagas
,
I. Garcia dos Santos
,
M. da Conceição
, and
P. Dunstan

Abstract  

The standard molar enthalpies of formation of crystalline dialkyldithiocarbamates chelates, [Pd(S2CNR2)2], with R=C2H5, n-C3H7, n-C4H9 and i-C4H9, were determined through reaction-solution calorimetry in acetone, at 298.15 K. From the standard molar enthalpies of formation of the gaseous chelates, the homolytic (172.43.8, 182.53.2,150.93.1 and 162.63.1 kJ mol−1) and heterolytic (745.03.8, 803.73.3,834.33.1 and 735.23.0 kJ mol−1) mean palladium-sulphur bond-dissociation enthalpies were calculated.

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Journal of Thermal Analysis and Calorimetry
Authors:
J. Regis Botelho
,
A. Duarte Gondim
,
I. Garcia dos Santos
,
P. Dunstan
,
A. Souza
,
V. Fernandes
, and
A. Araújo

Abstract  

The standard molar enthalpy of formation of crystalline dialkyldithiocarbamate chelates, [Pd(S2CNR2)2], with R=CH3 and i-C3H7, was determined through reaction-solution calorimetry in 1,2-dichloroethane, at 298 K. Using the standard molar enthalpies of formation of the gaseous chelates, the homolytic (52618 and 66610) and heterolytic (269318 and 295710 kJ mol-1) mean enthalpies of palladium-sulphur bond dissociation were calculated.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
P. Lam Ramos
,
D. Frías Fonseca
,
M. González Garcia
,
D. Aguiar Lambert
,
J. Estévez Alvarez
,
I. Pupo González
, and
D. López Sánchez

Abstract  

The objective of the present study was the elaboration of a procedure for the determination of Y, La, Ce, Pr and Nd in soils by spectrophotometry with Arsenazo III preceded by a separation-concentration stage, which includes coprecipitation and ion exchange. Multielement analysis by energy dispersive X-ray fluorescence (including Y, La, Ce and Nd) and flame atomic absorption spectrophotometry was carried out simultaneously in order to obtain a general characterization of the soil samples. Certified reference materials and statistical intercomparison of the obtained results were used to evaluate the accuracy of the methods. The precision was examined by analyzing replicate samples.

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Acta Alimentaria
Authors:
J.M. Garcia
,
S. M. Castro
,
R. Casquete
,
J. Silva
,
R. Queirós
,
J.A. Saraiva
, and
P. Teixeira

The effect of sequential treatments of pressure (50–150 MPa, 10 ºC, 5 min) and temperature (57 ºC, 15 min) on the survival and bacteriocin production of Pediococcus acidilactici HA-6111-2 cells in the exponential growth phase was assessed. The growth curves were fitted with the modified Gompertz model, and the estimated maximum specific growth rate was considered to be pressure dependent. A delay in the maximum value of bacteriocin production was registered for more severe pressure conditions, but it was found more notorious for pressure followed by temperature treatments. At lower pressure intensity treatment, regardless of the application order, there was an enhancement of bacteriocin production per cell when compared to the control while maintaining the maximum production value. Bacteriocin production after the treatments can be described by an exponential model.

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Acta Physiologica Hungarica
Authors:
Juan Martín-Hernández
,
P. Marín
,
H. Menéndez
,
J. Loenneke
,
M. Coelho-e-Silva
,
D. García-López
, and
A. Herrero

In order to ascertain whether differing structural mechanisms could underlie blood flow restricted training (BFRT) and high intensity training (HIT), this study had two aims: (i) to gain an insight into the acute variations of muscle architecture following a single bout of two different volumes of BFRT, and (ii) to compare these variations with those observed after HIT. Thirty-five young men volunteered for the study and were randomly divided into three groups: BFRT low volume (BFRT LV), BFRT high volume (BFRT HV) and traditional high intensity resistance training (HIT). All subjects performed a bilateral leg extension exercise session with a load of 20% of one repetition maximum (1RM) in the BFRT groups, whereas the load of the HIT group was equivalent to an 85% of their 1RM. Before and immediately after the exercise bout, ultrasound images were taken from the rectus femoris (RF) and the vastus lateralis (VL). All groups increased their RF (p < 0.001) and VL (p < 0.001) muscle thickness, while the increases in pennation angle were larger in HIT as compared to BFRT LV (p = 0.013) and BFRT HV (p = 0.037). These results support the hypothesis that acute muscle cell swelling may be involved in the processes underlying BFRT induced muscle hypertrophy. Furthermore, our data indicate differing structural responses to exercise between BFRT and HIT.

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Acta Physiologica Hungarica
Authors:
DJ Ramos-Campo
,
F Martínez-Sánchez
,
P Esteban-García
,
JA Rubio-Arias
,
VJ Clemente-Suarez
, and
JF Jiménez-Díaz

The aim of the present research was to analyze modifications on hematological and aerobic performance parameters after a 7-week intermittent hypoxia training (IHT) program. Eighteen male trained triathletes were divided in two groups: an intermittent hypoxia training group (IHTG: n: 9; 26.0 ± 6.7 years; 173.3 ± 5.9 cm; 66.4 ± 5.9 kg; VO2max: 59.5 ± 5.0 ml/kg/min) that conducted a normoxic training plus an IHT and a control group (CG: n: 9; 29.3 ± 6.8 years; 174.9 ± 4.6 cm; 59.7 ± 6.8 kg; VO2max: 58.9 ± 4.5 ml/kg/min) that performed only a normoxic training. Training process was standardized across the two groups. The IHT program consisted of two 60-min sessions per week at intensities over the anaerobic threshold and atmospheric conditions between 14.5 and 15% FiO2. Before and after the 7-week training, aerobic performance in an incremental running test and hematological parameters were analyzed. After this training program, the IHTG showed higher hemoglobin and erythrocytes (p < 0.05) values than in the CG. In terms of physiological and performance variables, between the two groups no changes were found. The addition of an IHT program to normoxic training caused an improvement in hematological parameters but aerobic performance and physiological variables compared to similar training under normoxic conditions did not increase.

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Journal of Behavioral Addictions
Authors:
William Van Gordon
,
Edo Shonin
,
Thomas J. Dunn
,
Javier Garcia-Campayo
,
Marcelo M. P. Demarzo
, and
Mark D. Griffiths

Background and aims

Workaholism is a form of behavioral addiction that can lead to reduced life and job satisfaction, anxiety, depression, burnout, work–family conflict, and impaired productivity. Given the number of people affected, there is a need for more targeted workaholism treatments. Findings from previous case studies successfully utilizing second-generation mindfulness-based interventions (SG-MBIs) for treating behavioral addiction suggest that SG-MBIs may be suitable for treating workaholism. This study conducted a controlled trial to investigate the effects of an SG-MBI known as meditation awareness training (MAT) on workaholism.

Methods

Male and female adults suffering from workaholism (n = 73) were allocated to MAT or a waiting-list control group. Assessments were performed at pre-, post-, and 3-month follow-up phases.

Results

MAT participants demonstrated significant and sustained improvements over control-group participants in workaholism symptomatology, job satisfaction, work engagement, work duration, and psychological distress. Furthermore, compared to the control group, MAT participants demonstrated a significant reduction in hours spent working but without a decline in job performance.

Discussion and conclusions

MAT may be a suitable intervention for treating workaholism. Further controlled intervention studies investigating the effects of SG-MBIs on workaholism are warranted.

Open access
Journal of Radioanalytical and Nuclear Chemistry
Authors:
J. D. T. Arruda-Neto
,
A. C. Cestari
,
C. B. Zamboni
,
M. Saiki
,
G. P. Nogueira
,
L. E. C. Fonseca
,
M. V. Manso-Guevara
,
A. Deppman
,
V. P. Likhachev
,
J. Mesa
,
O. A. M. Helene
,
S. A. C. Jorge
,
M. N. Martins
,
A. N. Gouveia
,
O. Rodriguez
,
F. Guzmán
, and
F. Garcia

Summary  

Neutron activation analysis has been used to study uranium incorporation in poultry bones as function of chow doped with: (a) uranium (20 ppm); (b) U-doped food (20 ppm) plus phytase (120 ppm) and (c) U-doped food (20 ppm) plus phytase (180 ppm). To investigate this situation experiments involving several groups of Cobb broilers was performed. Two animals per group were sacrificed weekly up to their adultness and uranium concentration in the tibia was measured. It was observed that the concentration of uranium (µg U/g bone) is decreasing all along the animal life spanning period of 14-42 days. This behavior suggests that the skeleton mass is growing faster than the corresponding accumulation of uranium. The administration of phytase seems not to alter this scenario.

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