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381.
The plastination technique produces non-toxic human tissues, ensuring their safe handling in educational settings. This investigation aimed to understand if visually impaired students profit from the use of plastinated anatomical specimens in learning the anatomy of the nervous system. For this purpose, their learning performance was compared to sighted and blindfolded students recruited from three primary schools in Fortaleza city, in the state of Ceará. Initially, a questionnaire was applied before carrying out the pedagogical practice, followed by an anatomy lecture with practical components with the use of plastinated anatomical specimens and synthetic anatomical models of the nervous system. After these steps, the students answered the questionnaire previously applied. Our results showed that the tactile perception of the visually impaired participants was significantly more developed compared to sighted (p < 0.001) and the blindfolded (p < 0.0001) students. The average of correct answers in the reapplied questionnaire was higher in the groups that used plastinated specimens (p < 0.05). In conclusion, the use of plastinated specimens has proven to be an effective tool in promoting a better understanding of anatomical structures, mainly for students with or without visual impairments, making it a valuable asset in anatomy teaching.  相似文献   
382.
Post-scandal effects in public management point to the occurrence of overcompliance in the work of public managers, leading to reluctance and paralysis in decision-making. This article discusses the proposition of an artifact in the form of a warning system to aid the analysis process and issuing of opinions (APIO) by public managers, providing more information and, consequently, less risk and fear. The Design Science Research method was used to exapt a scientific artifact to the context of public management. The textual structure of 178 opinions issued by public agencies was analyzed, as was the perception of 17 public managers of the characteristics of the APIO. Exaptating the artifact from a technological perspective is simple and feasible, as it involves processes with strong functional similarities. The greatest challenges to operationalize the artifact broadly and without restrictions, as occurs in scientific academia, are associated with informational behaviors.  相似文献   
383.
This study investigated the effects of different reduced strength training (RST) frequencies on half-squat 1 RM and quadriceps cross-sectional area (QCSA). Thirty-three untrained males (24.7?±?3.9 years; 1.73?±?0.08?m; 74.6?±?8.4?kg) underwent a 16-week experimental period (i.e. eight weeks of strength training [ST] followed by additional eight weeks of RST). During the ST period, the participants performed 3–4 sets of 6–12 RM, three sessions/week in half-squat and knee extension exercises. Following ST, the participants were randomly allocated to one of three groups: reduced strength training with one (RST1) or two sessions per week (RST2), and ceased training (CT). Both RST1 and RST2 groups had their training frequency and total training volume-load (i.e. RST1?=?50.3% and RST2?=?57.1%) reduced, while the CT group stopped training completely. Half-squat 1 RM (RST1?=?27.9%; RST2?=?26.7%; and CT?=?28.4%) and QCSA (RST1?=?6.1%; RST2?=?6.9%; and CT?=?5.8%) increased significantly (p?<?.05) in all groups after eight weeks of ST. No significant changes were observed in 1 RM and QCSA for RST1 and RST2 groups after the RST period, while the CT group demonstrated a decrease in half-squat 1 RM (22.6%) and QCSA (5.4%) when compared to the ST period (p?<?.05). In conclusion, different RST frequencies applied were able to maintain muscle mass and strength performance obtained over the regular ST period. Thus, it appears that RST frequency does not affect the maintenance of muscle mass and strength in untrained males, as long as volume-load is equated between frequencies.  相似文献   
384.
385.
The development of local technology-intensive suppliers (t-suppliers) may contribute to both reinforcing the industrial base and supporting the competitiveness of primary production in developing countries. This article explores the role of t-suppliers in natural resource-based economies and outlines a theoretical framework for the analysis of the factors which foster or constrain their development and defines areas for an effective promotion. The proposed model of analysis distinguishes between factors influencing the development of t-suppliers on the level of the main industry, the level of supplier firms or firm-level and the level of external determinants with special reference to industrial policy factors.  相似文献   
386.
Background: We aimed to evaluate the influence of the level of effort during four basic resistance exercises leading to muscular failure on intraocular pressure (IOP) and ocular perfusion (OPP), as well as the role of exercise type and sex. Methods: Twenty-five young adults (12 women) performed 10 repetitions against their 10-RM (repetition maximum) load in the squat, military press, biceps curl and calf raise exercises. IOP was measured before, during and after exercise, whereas OPP was indirectly assessed before and after each exercise. Results: There was a progressive IOP rise during exercise (p?η²?=?0.531), which was dependent on exercise type (p?=?0.020, η²?=?0.125). The squat exercise induced higher IOP increments in comparison to the other exercises (corrected p-values?p-values?=?0.012 and 0.002). OPP exhibited a significant reduction when leading to muscular failure (p?=?0.001, η²?=?0.364), being statistically significant for the squat and military press exercises (corrected p-values?=?0.037 and 0.047). No effect of sex was found for IOP and OPP (p?>?0.05). Conclusions: A single set of resistance training leading to muscular failure causes an instantaneous and progressive IOP rise in healthy young individuals. These IOP rises depend on exercise type (squat?>?military press?=?biceps curl?>?calf raise), but not on participant´s sex. OPP diminished as a consequence of performing resistance training exercise, being statistically significant for the squat and military press exercises. Future studies should include glaucoma patients aiming to corroborate the generalizability of our findings.  相似文献   
387.
Effective force and economy of triathletes and cyclists   总被引:1,自引:0,他引:1  
The effective force applied on the crank, the index of pedalling effectiveness, and the economy of movement at 60, 75, 90, and 105 rev/min cadences were examined in nine cyclists and eight triathletes. Tests were performed on two days. Maximal oxygen uptake was measured and the second ventilatory threshold was estimated on day 1 using a stationary bicycle. On day 2, the four different cadences were tested at about 5% below the second ventilatory threshold. A strain gauge instrumented clip-less pedal mounted on the bicycle enabled us to measure the normal and tangential forces exerted on the pedal, while the pedal and crank angles were monitored with the aid of a video system. Based on this information, the effective force and the index of pedalling effectiveness were calculated. Cyclists produced significantly more effective force and a higher index of pedalling effectiveness at 60 and 75 rev/min and were significantly more economic at all cadences than triathletes. The significant and positive correlation between effective force and economy at all cadences suggests that improvement of the effective force would reflect on economy.  相似文献   
388.
This study shows that the sandstone used in the construction of the Church of San Mateo in Tarifa (Cádiz, Spain) is highly sensitive to processes of decay because of a combination of factors that are intrinsic and extrinsic to the material. The mineralogy, texture and porous system of the sandstone and the proximity of the church to the sea all play a part in these processes. X-ray diffraction reveals that there are interstratified chlorite/smectite clays among the minerals that make up the rock. These mixed layer clays have been shown to undergo hydric expansion. This phenomenon may be accompanied and augmented by the presence of NaCl which acts as an electrolyte in osmotic swelling processes. Two varieties of sandstone were used in the construction of the church, namely grey sandstone and brown sandstone. The latter is more porous and undergoes greater hydric expansion, showing a higher degree of deterioration. Ultrasound analysis has demonstrated that both varieties are anisotropic because they contain bedding planes and are affected by the preferred orientation of the phyllosilicates in the rock. The anisotropic nature of these stones was confirmed by capillary suction tests. The capillary front reaches a relatively low height which means that when water is absorbed, the anisotropic textural properties combined with the presence of chlorite–smectite mixed layers in the sandstone result in mechanical (shear) stress between the first few centimetres of the wet stone and the dry area behind. The latter effect favours the development of flakes, so causing the decay of the ornamental stone and the church façade.  相似文献   
389.
390.
ABSTRACT

The purpose of this study was to investigate the validity of a smartphone app to measure biomechanical barbell parameters during the snatch. Ten collegiate NCAA division I athletes performed two repetitions each at 40, 50, 60, 70, and 80% of their 1-repetition maximum snatch. Barbell motions were simultaneously recorded with a motion capture system and the smartphone app. The motion capture system recorded the 3-D position of a reflective marker attached to the end of the barbell while the smartphone app was used to record sagittal plane video and track the shape of the weight plate from which the barbell center was derived. Peak forward (PFD) and backward (PBD) displacements and peak vertical displacement (PVD) and velocity (PVV) were calculated from both sets of data. Significant, strong to very strong Pearson’s product-moment correlation coefficients between both systems were noted for all parameters (r = 0.729–0.902, all p < 0.001). Small significant biases between systems were observed for PVD (ES = 0.284, p < 0.001) and PFD (ES=0.340, p < 0.01), while trivial to small, non-significant biases were observed for PBD (ES = 0.143) and PVV (ES = –0.100). Collectively, the results suggest that the app can provide biomechanical data of barbell motions similar to a 3-D motion capture system.  相似文献   
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