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1.
J Sci Med Sport ; 25(6): 505-510, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35346580

RESUMEN

OBJECTIVES: To measure motor competence among a representative sample of Iranians aged 5-85 years. DESIGN: Cross-sectional. METHODS: Motor competence was assessed quantitatively by the Test of Motor Competence; two fine motor skills (placing and building bricks) and two gross motor skills (heel-to-toe-walking and walking/running in slopes) to assess dynamic balance. Task scores were summed and transformed into standardized scores (z-scores). Data were stratified by 12 chronological age groups and sex. RESULTS: Participants were 500 Iranians aged 5-85 years (females = 64%, age 5-35 years = 82%). There were significant age differences in motor competence and the distribution between age and z-score distribution was u-shaped. Between childhood and adolescence there was a rapid improvement in motor competence with maximal speed (-2 standard deviations) occurring among 19-25-year-olds. For each decade after age 25 years, z-scores progressively decreased approximately 1 standard deviations until age ≥56 years when performance decreased to approximately the same speeds as children (> +3 standard deviations). Sex differences were observed between children and adolescents. CONCLUSIONS: The sample characteristics constrain the generalizability of our findings. The Test of Motor Competence is easy to administer, uses a standardized test battery for people aged 5-85 years, and the quantitative outcome enables longitudinal monitoring of motor competence across the life course. As life expectancy and the proportion of populations aged >65 years increases, understanding how to maintain health in older age is an important public health issue in 21st century.


Asunto(s)
Longevidad , Destreza Motora , Adolescente , Niño , Estudios Transversales , Femenino , Humanos , Irán , Masculino , Caminata
3.
Nat Commun ; 10(1): 4859, 2019 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-31649270

RESUMEN

An invisibility cloak should completely hide an object from an observer, ideally across the visible spectrum and for all angles of incidence and polarizations of light, in three dimensions. However, until now, all such devices have been limited to either small bandwidths or have disregarded the phase of the impinging wave or worked only along specific directions. Here, we show that these seemingly fundamental restrictions can be lifted by using cloaks made of fast-light media, termed tachyonic cloaks, where the wave group velocity is larger than the speed of light in vacuum. On the basis of exact analytic calculations and full-wave causal simulations, we demonstrate three-dimensional cloaking that cannot be detected even interferometrically across the entire visible regime. Our results open the road for ultrabroadband invisibility of large objects, with direct implications for stealth and information technology, non-disturbing sensors, near-field scanning optical microscopy imaging, and superluminal propagation.

4.
Neotrop Entomol ; 46(2): 203-209, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27679495

RESUMEN

The resistance of 11 tomato cultivars (Ps-6515, Berlina, Poolad, Petoprid-5, Zaman, Matin, Golsar, Sandokan-F1, Golshan-616, Sadeen-95 and Sadeen-21) to the tomato moth, Tuta absoluta (Meyrick) (Lepidoptera:Gelechiidae) was investigated under field conditions. A randomized complete block design was used with three replications. Data analysis indicated that there were significant differences (P < 0.05) among cultivars regarding leaflet damage, leaf damage, overall plant damage, number of mines per leaf, number of holes on the stem, and fruit. Our findings revealed that the cultivars Berlina, Golsar, Poolad, and Zaman were less suitable cultivars, suggesting that they are more resistant to the tomato moth than the other cultivars. The high density of leaf trichomes present in the cultivars Berlina, Zaman, and Golsar can be one of the possible causes of resistance to T. absoluta. Knowledge of the extent of susceptibility or resistance of cultivars to a pest on a crop is one of the fundamental components of integrated pest management (IPM) programs for any crop.


Asunto(s)
Mariposas Nocturnas , Solanum lycopersicum , Animales , Control de Plagas , Hojas de la Planta
5.
Pak J Biol Sci ; 10(24): 4563-6, 2007 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-19093534

RESUMEN

Laboratory experiments were conducted to measure the functional and numerical responses of Stethorus gilvifrons Mulsant feeding on Tetranychus turkestani Ugarov and Nikolski. Adult ladybirds were isolated singly for 24 h in 8 cm petri dishes with either 4, 8, 12, 24, 48 or 96 adult females of T. turkestani. Results showed a typical type 3 functional response, with up to 65.2 preys attacked when 96 preys were provided. The rate of attack and handling time were 0.0012 and 0.415 (days), respectively. The number of eggs deposited by the predator depended on the density of the prey; up to maximum of 223.6 eggs female(-1) at prey density of 96 spider mites were recorded. No eggs were laid at densities of 4 and 8 prey/arena.


Asunto(s)
Escarabajos/patogenicidad , Ácaros/parasitología , Animales , Escarabajos/fisiología , Magnoliopsida/parasitología , Control Biológico de Vectores/métodos , Hojas de la Planta/parasitología , Densidad de Población , Conducta Predatoria
6.
J Res Health Sci ; 7(2): 25-30, 2007 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-23343921

RESUMEN

BACKGROUND: This study examined the applicability of trans-theoretical model (TTM) to understand exercise behavior among female college students in Hamadan University of Medical Sciences, Iran in 2007. METHODS: A cross-sectional descriptive study was conducted. The dependent variables analyzed were exercise efficacy expectation, decisional balance (pros and cons). The independent variable was stage of exercise behavior change. Five hundred and ninety female students representing various disciplines on campus completed a valid and reliable questionnaire (r = 0.78) during regularly scheduled classes. More than seventy-three percent of sample were sedentary (pre-contemplation, contemplation, or preparation) whereas 24.6% were in the action stage (regularly active < 6 months) and 2.2% were in the maintenance stage (regularly active > 6 months). RESULTS: All of the TTM constructs differed significantly across exercise stages. Students in pre-contemplation scored the lowest and those in maintenance stage scored highest on efficacy expectation and pros and reversed on cons. CONCLUSION: Results supported the use of the entire TTM in examining exercise behavior among female college students.

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