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Abstract
This study deals with the characterization of a marine sediments profile from the Gulf of Tehuantepec, Mexico. Ten sediment samples obtained from a core of 18.3 m of length were analysed. Although there have been numerous marine sediments studies carried out in Mexico, more are needed to better understand the sea floor formation. Crystallographic, morphologic, physical, chemical and gamma ray activity analysis were carried out on the samples. The analysis results showed a decrease in organic matter content as a function of sea depth; this value is related to the specific surface area. Some hazardous materials as Cr, Mn, Ni, Sr and Hg were also identified by PIXE in some samples, probably due to anthropogenic activity. The presence of uranium a naturally occurring element was found in all the samples, suggesting a migration through all materials of strata, radioactive elements such as 226Ra, 235U, 212Pb, 214Pb, 228Ac, 208Ti, 214Bi, 228Ac and 40K were detected.
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.
The goal of this study was to determine whether traditional ergoespirometric incremental exercise testing carried out to the point of exhaustion could be useful in distinguishing the physiological profiles of elite runners that compete in races that lasted about 8 minutes versus those that lasted about 2 hours. Ten male marathon runners (performance time: 2:12:04, coefficient of variation (CV) = 2.33%) and 8 male 3000 m steeplechase runners (performance time: 8:37.83, CV = 2.12%) performed an incremental test on the treadmill (starting speed 10 km·h−1; increments, 2 km·h−1; increment duration, 3 min to exhaustion). Heart rate (HR), VO2, and lactate concentrations were measured at the end of each exercise level. At maximal effort, there were no differences between the groups regarding VO2max and maximal HR; however, the workload time, vVO2max and peak treadmill velocity were significantly higher in the 3000 m steeplechase group (p<0.05). At submaximal effort, there were no significant differences between groups for VO2 (ml·kg−1·min−1), HR, or lactate. Our results show that this type of testing was not sufficient for discriminating the physiological profiles of elite runners who competed in middle-distance versus long-distance events (e.g. in the marathon and the 3000 m steeplechase).
Abstract
This article reports the thermodynamic changes of lipid nanoparticles (LN) upon delivery of lipophilic vitamin E derivatives to the skin. Skin penetration of α-tocopherol (α-T) and α-tocopherol acetate (α-Ta) into and across porcine ear skin was investigated in vitro using tape-stripping test in modified Franz diffusion cells. Wide angle X-ray scattering (WAXS) and differential scanning calorimetry (DSC) have been used to characterize the polymorphism of the solid matrix of LN before and after in vitro skin penetration assay. Cetyl palmitate LN with a loading capacity of 20% of vitamin E derivatives (with regard to the lipid matrix) have shown the typical β’ modification of waxes, with a crystallinity index (%CI) between 30 and 40%. Mean particle size and shelf life stability was assessed by static (laser diffractometry, LD) and dynamic (photon correlation spectroscopy, PCS) light scattering techniques. Submicron-sized LN were produced, i.e., 99% of LN showed a size below 600 nm immediately after production. A mean size between 180 and 350 nm (polydispersity index < 0.25) was obtained for LN stored at both 8 and 22 °C, and this size range was kept constant for at least 20 days of shelf life. Quantification of α-T and α-Ta in the skin using tape-stripping provided a 3.4-fold increase in the level of actives within the stratum corneum (SC) and 1.3-fold increase in the viable epidermis (VE). LN increased skin penetration of both actives, following a cumulative release during 8 h in modified Franz diffusion cells. The differences in the distribution levels observed between α-T and α-Ta when delivered via LN was due to the different thermodynamic activity of both actives, i.e., following increased partition coefficient of α-Ta into SC and VE, in comparison to α-T.
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.
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.
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.
Abstract
The solubility of europium at 0.02M, 0.1M and 0.7M NaClO4 ionic strength solutions was determined by a radiometric method and pEus-pCH diagrams were obtained. Hydrolysis constants were also determined at the same ionic strengths by pH titration and the values found were log *
1 = -7.68±0.11, -8.07±0.10 and -8.20±0.11. The log K
sp values were -23.5±0.2, -22.7±0.2 and -21.9±0.2 for 0.02M, 0.1M and 0.7M NaClO4 ionic strengths, respectively, at 303 K under CO2-free conditions and the extrapolated value at zero ionic strength was log K
sp
0 = -24.15. The working pCH ranges for the calculation of the hydrolysis constants were selected from the pEus-pCH diagrams in the region where precipitation of europium oxide or hydroxide was less than 20%. Europium removal from aqueous solutions with zeolites was explored.
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.
Abstract
Background and aims
Compulsive Sexual Behavior Disorder (CSBD) is characterized by a persistent failure to control intense and recurrent sexual impulses, urges, and/or thoughts, resulting in repetitive sexual behavior that causes a marked impairment in important areas of functioning. Despite its recent inclusion in the forthcoming ICD-11, concerns regarding its assessment, diagnosis, prevalence or clinical characteristics remain. The purpose of this study was to identify participants displaying CSBD through a novel data-driven approach in two independent samples and outline their sociodemographic, sexual, and clinical profile.
Methods
Sample 1 included 1,581 university students (females = 56.9%; M age = 20.58) whereas sample 2 comprised 1,318 community members (females = 43.6%; M age = 32.37). First, we developed a new composite index to assess the whole range of CSBD symptoms based on three previously validated scales. Based on this new composite index, we subsequently identified individuals with CSBD through a cluster analytic approach.
Results
The estimated occurrence of CSBD was 10.12% in sample 1 and 7.81% in sample 2. Participants with CSBD were mostly heterosexual males, younger than respondents without CSBD, reported higher levels of sexual sensation seeking and erotophilia, an increased offline and especially online sexual activity, more depressive and anxious symptoms, and poorer self-esteem.
Conclusions
This research provides further evidence on the occurrence of CSBD based on an alternative data-driven approach, as well as a detailed and nuanced description of the sociodemographic, sexual, and clinical profile of adults with this condition. Clinical implications derived from these findings are discussed in detail.
