474 research outputs found

    Supported magnetic nanoclusters: Softlanding of Pd clusters on a MgO surface

    Full text link
    Low-energy deposition of neutral Pd_N clusters (N=2-7 and 13) on a MgO(001) surface F-center (FC) was studied by spin-density-functional molecular dynamics simulations. The incident clusters are steered by an attractive "funnel" created by the FC, resulting in adsorption of the cluster, with one of its atoms bonded atop of the FC. The deposited Pd_2-Pd_6 clusters retain their gas-phase structures, while for N>6 surface-commensurate isomers are energetically more favorable. Adsorbed clusters with N > 3 are found to remain magnetic at the surface.Comment: 5 pages, 2 figs, Phys.Rev.Lett., accepte

    Electronic-structure-induced deformations of liquid metal clusters

    Full text link
    Ab initio molecular dynamics is used to study deformations of sodium clusters at temperatures 5001100500\cdots 1100 K. Open-shell Na14_{14} cluster has two shape isomers, prolate and oblate, in the liquid state. The deformation is stabilized by opening a gap at the Fermi level. The closed-shell Na8_8 remains magic also at the liquid state.Comment: REVTex, 11 pages, no figures, figures (2) available upon request (e-mail to hakkinen at jyfl.jyu.fi), submitted to Phys. Rev.

    Effects of upper body eccentric versus concentric strength training and detraining on maximal force, muscle activation, hypertrophy and serum hormones in women

    Get PDF
    Effects of eccentric (ECC) versus concentric (CON) strength training of the upper body performed twice a week for 10 weeks followed by detraining for five weeks on maximal force, muscle activation, muscle mass and serum hormone concentrations were investigated in young women (n = 11 and n = 12). One-repetition bench press (1RM), maximal isometric force and surface electromyography (EMG) of triceps brachii (TB), anterior deltoid (AD) and pectoralis major (PM), cross-sectional area (CSA) of TB (Long (LoH) and Lateral Head (LaH)) and thickness of PM, as well as serum concentrations of free testosterone, cortisol, follicle-stimulating hormone, estradiol and sex hormone-binding globulin were measured. ECC and CON training led to increases of 17.2 ± 11.3% (p \u3c 0.001) and 13.1 ± 5.7% (p \u3c 0.001) in 1RM followed by decreases of-6.6 ± 3.6% (p \u3c 0.01) and-8.0 ± 4.5% (p \u3c 0.001) during detraining, respectively. Isometric force increased in ECC by 11.4 ± 9.6 % (p \u3c 0.05) from week 5 to 10, while the change in CON by 3.9±6.8% was not significant and a between group difference was noted (p \u3c 0.05). Maximal total integrated EMG of trained muscles increased only in the whole subject group (p \u3c 0.05). CSA of TB (LoH) increased in ECC by 8.7 ± 8.0% (p \u3c 0.001) and in CON by 3.4 ± 1.6% (p \u3c 0.01) and differed between groups (p \u3c 0.05), and CSA of TB (LaH) in ECC by 15.7 ± 8.0% (p \u3c 0.001) and CON by 9.7 ± 6.6% (p \u3c 0.001). PM thickness increased in ECC by 17.7 ± 10.9% (p \u3c 0.001) and CON by 14.0 ± 5.9% (p \u3c 0.001). Total muscle sum value (LoH + LaH + PM) increased in ECC by 12.4 ± 6.9% (p \u3c 0.001) and in CON by 7.1 ± 2.9% (p \u3c 0.001) differing between groups (p \u3c 0.05) and decreased during detraining in ECC by-6.5 ± 4.3% (p \u3c 0.001) and CON by-6.1 ± 2.8% (p \u3c 0.001). The post detraining combined sum value of CSA and thickness was in ECC higher (p \u3c 0.05) than at pre training. No changes were detected in serum hormone concentrations, but baseline free testosterone levels in the ECC and CON group combined correlated with changes in 1RM (r = 0.520, p \u3c 0.016) during training. Large neuromuscular adaptations of the upper body occurred in women during ECC, and CON training in 10 weeks. Isometric force increased only in response to ECC, and total muscle sum value increased more during ECC than CON training. However, no changes occurred in serum hormones, but individual serum-free testosterone baseline concentrations correlated with changes in 1RM during strength training in the entire group. Both groups showed significant decreases in neuromuscular performance and muscle mass during detraining, while post detraining muscle sum value was only in ECC significantly higher than at pre training

    Actively open-minded thinking : development of a shortened scale and disentangling attitudes towards knowledge and people

    Get PDF
    Actively open-minded thinking (AOT) is often used as a proxy for reflective thinking in research on reasoning and related fields. It is associated with less biased reasoning in many types of tasks. However, few studies have examined its psychometric properties and criterion validity. We developed a shortened, 17-item version of the AOT for quicker administration. AOT17 is highly correlated with the original 41-item scale and has highly similar relationships to other thinking dispositions, social competence and supernatural beliefs. Our analyses revealed that the AOT is not a unitary construct, but comprises four distinct dimensions, some of which concern attitudes towards knowledge, and others concern attitudes towards people. This factor structure was replicated in another data-set, and correlations with other measures in four data-sets (total N = 3345) support the criterion validity of these dimensions. Different dimensions were responsible for the AOT's relationships with other thinking dispositions.Peer reviewe

    Structure and Magnetism of Neutral and Anionic Palladium Clusters

    Full text link
    The properties of neutral and anionic Pd_N clusters were investigated with spin-density-functional calculations. The ground state structures are three-dimensional for N>3 and they are magnetic with a spin-triplet for 2<=N<=7 and a spin nonet for N=13 neutral clusters. Structural- and spin-isomers were determined and an anomalous increase of the magnetic moment with temperature is predicted for a Pd_7 ensemble. Vertical electron detachment and ionization energies were calculated and the former agree well with measured values for anionic Pd_N clusters.Comment: 5 pages, 3 figures, fig. 2 in color, accepted to Phys. Rev. Lett. (2001

    Factors affecting young adults’ willingness to try novel health-enhancing nature-based products

    Get PDF
    One of the megatrends that affects consumers' preferences is a growing interest in health, well-being and self-care. This study explores consumer perceptions of a health-enhancing nature-based substance. Based on a survey data (N = 944) collected among national and international students in Finland, we examined factors that affect young adults' willingness to try products containing the substance. The results showed a relatively high willingness to try the products, particularly among female and non-Finnish respondents. Relationship to nature and beliefs related to the health benefits or risks of soil microbes influenced willingness to try products. The results highlight the importance of accounting for consumer perceptions in the innovation process.Peer reviewe

    Exercise medicine for cancer cachexia: Targeted exercise to counteract mechanisms and treatment side-effects

    Get PDF
    Purpose: Cancer-induced muscle wasting (i.e., cancer cachexia, CC) is a common and devastating syndrome that results in the death of more than 1 in 5 patients. Although primarily a result of elevated inflammation, there are multiple mechanisms that complement and amplify one another. Research on the use of exercise to manage CC is still limited, while exercise for CC management has been recently discouraged. Moreover, there is a lack of understanding that exercise is not a single medicine, but mode, type, dosage, and timing (exercise prescription) have distinct health outcomes. The purpose of this review was to examine the effects of these modes and subtypes to identify the most optimal form and dosage of exercise therapy specific to each underlying mechanism of CC. Methods: The relevant literatures from MEDLINE and Scopus databases were examined. Results: Exercise can counteract the most prominent mechanisms and signs of CC including muscle wasting, increased protein turnover, systemic inflammation, reduced appetite and anorexia, increased energy expenditure and fat wasting, insulin resistance, metabolic dysregulation, gut dysbiosis, hypogonadism, impaired oxidative capacity, mitochondrial dysfunction, and cancer treatments side-effects. There are different modes of exercise, and each mode has different sub-types that induce vastly diverse changes when performed over multiple sessions. Choosing suboptimal exercise modes, types, or dosages can be counterproductive and could further contribute to the mechanisms of CC without impacting muscle growth. Conclusion: Available evidence shows that patients with CC can safely undertake higher-intensity resistance exercise programs, and benefit from increases in body mass and muscle mass
    corecore