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1.
Artículo en Inglés | MEDLINE | ID: mdl-36141765

RESUMEN

There have been reports of food hypersensitivity reactions to food additives (HFA) for many years. The mechanisms of HFA and their frequency are difficult to precisely define, as most of the data come from outdated studies with poor methodology. In 2020, the European Food Safety Authority completed a review of additives, examining their influence on the occurrence of HFA, but did not include all of them. The aim of this review is to systematise knowledge about selected groups of food additives (FAs) and the HFA induced by them. We also briefly discuss the issues of diagnosis and therapy in this disease. FAs are commonly used in prosscessed foods, but HFA appears to be a rare phenomenon. Identification of the FA responsible for hypersensitivity and its treatment is difficult. Diagnosis is a challenge for the clinician and for the patient. A food diary is a helpful diagnostic tool. It allows diet therapy to be monitored based on the partial or complete elimination of products containing a harmful additive. An elimination diet must not be deficient, and symptomatic pharmacotherapy may be necessary if its application is ineffective. Taking all this into account, we conclude that it is necessary to conduct randomised multicentre studies based on the double-blind placebo control protocol in this field.


Asunto(s)
Aditivos Alimentarios , Hipersensibilidad a los Alimentos , Antioxidantes , Aromatizantes , Aditivos Alimentarios/efectos adversos , Hipersensibilidad a los Alimentos/diagnóstico , Hipersensibilidad a los Alimentos/epidemiología , Conservantes de Alimentos , Humanos , Conservadores Farmacéuticos , Ensayos Clínicos Controlados Aleatorios como Asunto
2.
J Hum Kinet ; 78: 49-58, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34025863

RESUMEN

An effective visual perception strategy helps a fencer quickly react to an opponent's actions. This study aimed to examine and compare visual perception strategies used by high-performance foil fencers (experts) and beginners. In an eye tracking experiment, we analysed to which areas beginning and expert fencers paid attention during duels. Novices paid attention to all examined areas of interest comprising the guard, foil (blade and tip), armed hand, lower torso, and upper torso of their opponents. Experts, however, paid significantly less attention to the foil, picking up information from other areas, mainly the upper torso and the armed hand. These results indicate that expert fencers indeed engage different visual perception strategies than beginners. The present findings highlight the fact that beginner fencers should be taught already in the early stages of their careers how to pick up information from various body areas of their opponents.

3.
Foods ; 9(11)2020 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-33171600

RESUMEN

The relations of the antiradical capacity to oxidative stability parameters and the contents of fatty acids, sterols, tocopherols, phenols, flavonoids, chlorophyll, Cu, and Fe were assessed in 33 cold-pressed seed oils: Walnut (7 brands of oils), rosehip (3), camelina (6), milk thistle (5), flax (6), and pumpkin (6). The antiradical capacity of oils depended strongly on tocopherol contents with a synergistic effect with polyphenols. The efficacy of tocopherols in cold-pressed oils was accompanied by a negative correlation of their antioxidant capacity with the peroxide value increase after 3 months of shelf life. This study also showed a positive correlation between the content of phytosterols and the antiradical capacity in the lipophilic fraction of cold-pressed oils rich in n-3 polyunsaturated fatty acids (PUFAs). Multiple regression analysis identified groups of antioxidants naturally occurring in cold-pressed oils in relation to their fatty acid composition, which added to the cold-pressed oils could provide possible strategies to improve their stability. Achieving high stability is primarily a result of high phytosterol content exceeding the molar ratio of 1:100 for total phytosterols to α-linolenic acid. However, the molar ratios of tocopherols to linoleic acid below 1:2000 and polyphenols to linoleic acid below 1:3000 does not prevent oxidation in oils with the predominance of linoleic acid.

4.
Artículo en Inglés | MEDLINE | ID: mdl-32818057

RESUMEN

BACKGROUND: According to research, fast skating on short distances increases functional asymmetry of leg muscles. As has been proven in many sporting disciplines, this asymmetry can increase the risk of injury. The aim of the study was to analyze the level of right and left myolectrical manifestations of fatigue asymmetry of gluteus maximus muscle in elite skaters on a short track and to compare this phenomenon to a control group. The muscles were chosen deliberately, due to their influence in maintaining the right position during training on ice. METHODS: The experiment compared a group of eight members of the Polish Women's National Team in short track with a group of eight non-training people. The subjects did the Biering-Sorensen test, in which sEMG (surface electromyography) signal frequency was measured in the gluteus maximus muscles during an isometric contraction. Myolectrical manifestations of fatigue slopes were analyzed with a ANOVA with repeated measures. In the skaters, the myolectrical manifestations of fatigue differed between the right and the left gluteus maximus muscles. All the skaters had higher myolectrical manifestations of fatigue in the right leg. This phenomenon was not observed in the non-training subjects, who on average had similar myolectrical manifestations of fatigue in both legs. RESULTS: Results showed that the right and the left muscles of the skaters in the experimental group differed in myolectrical manifestations of fatigue, but this difference was non-significant in the control group.The subjects from the two groups did not differ in the myolectrical manifestations of fatigue of the left muscle, they did in the myolectrical manifestations of fatigue of the right muscle. The elite speed-track skaters had higher myolectrical manifestations of fatigue in the right muscle than the non-training subjects. CONCLUSIONS: Training should thus be planned in a way that minimizes the risk of causing muscle myolectrical manifestations of fatigue asymmetry in skaters despite the typically asymmetrical muscle work during training on ice and competition, thus new training protocols should be developed or considered to decrease that asymmetry. TRIAL REGISTRATION: The tests were previously approved by the Bioethical Commission of the Chamber of Physicians in Opole. (Resolution No. 235 of 13 December 2016).

5.
Biomed Res Int ; 2020: 4636271, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32420345

RESUMEN

Left handers have long held the edge over right handers in one-on-one interactive combat sports. Particularly in fencing, top rankings show a relatively strong overrepresentation of left handers over right handers. Whether this can be attributed to perceptual strategies used by fencers in their bouts remains to be established. This study aims to verify whether right-handed fencers assess their opponents' behaviour based on different perceptual strategies when fencing a left vs. right hander. Twelve top-level (i.e., Olympic fencers, Junior World Team Fencing Champions, and top Polish senior foil fencers) right-handed female foil fencers (aged 16-30 years) took part in the study. They performed a total of 40 actions: 10 repetitions of offensive actions (attack) and 10 repetitions of defensive actions (defence), each type of action performed under 2 conditions (right- vs. left-handed opponent). While the participants were fencing, their eye movements were being recorded with a remote eye-tracker (SMI ETG 2.0). Both in their offensive and defensive actions, the fencers produced more fixations to the armed hand and spent more time observing the armed hand in duels with a left-handed (vs. right-handed) opponent. In defence, it was also the guard that attracted more fixations and gained a longer observation time in bouts with a left hander. In duels with a right-handed opponent, a higher number of fixations in attack and in defence, and longer observation times in defence were found for the upper torso. The results may point to different perceptual strategies employed in bouts with left- vs. right-handed individuals. The findings from this study may help to promote the implementation of specialized perceptual training programmes in foil fencing.


Asunto(s)
Movimientos Oculares/fisiología , Lateralidad Funcional/fisiología , Desempeño Psicomotor/fisiología , Deportes/fisiología , Adolescente , Adulto , Femenino , Humanos , Adulto Joven
6.
Artículo en Inglés | MEDLINE | ID: mdl-32013174

RESUMEN

This paper reports the results of an experiment that aimed to study transfer training in fencing. Fencers from the experimental group underwent six-week transfer training while those from the control group underwent regular fencing training. The fencers' performance was analyzed thrice: before the experimental training (pretest), immediately after it (posttest), and four weeks after it (retention test). Using a device that simulates fencing moves and analyzes the accuracy of such performance, participants completed, with both hands, three tests related to straight thrust accuracy. While no differences in hand grip strength was observed between the two groups across the three tests, significant differences occurred in terms of their performance on the device. The groups did not differ in the pretests and the retention tests. However, the fencers from the experimental group generally performed better in postests than prestests. These results show that bilateral transfer can be effective in foil fencing training, although its positive effects are short-term. In order to be effective, transfer training should be used as a regular training tool.


Asunto(s)
Rendimiento Atlético/fisiología , Fuerza de la Mano , Mano , Deportes/fisiología , Lateralidad Funcional , Humanos , Destreza Motora
7.
J Mot Behav ; 52(1): 50-57, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-30849297

RESUMEN

Previous studies showed that motor asymmetries are reduced in left-handers and after a long-term fencing training in right-handers. Interestingly, left-handed athletes are substantially over-represented in elite fencing. These findings have been speculatively explained by imbalance in experience of fighting opposite handedness opponents resulted from skewed distribution of handedness, i.e. lefties encounter more righties than righties encounter lefties. Whereas these assumptions could be accurate, the underlying mechanisms remain ambiguous. In this study, we investigated effects of fencing training on motor performance and asymmetry with respect to handedness. We compared fencing performance of left- and right-handed fencers in both training and combat conditions. In the combat condition, left-handers won seven out of twelve matches consisted of twelve bouts each. They also showed a significantly longer hit detection time, a measure indicating better quality of fencing attack. In the training condition, left-handed fencers completed fencing board tests significantly faster than right-handers. These findings provide additional factor of superior motor performance to be considered when interpreting over-representation of lefties in elite fencing. Furthermore, our left-handers were less lateralized, which could explain that superior motor performance. This idea is consistent with previous findings of reduced asymmetry in right-handed fencers when comparing to non-athletes.


Asunto(s)
Rendimiento Atlético/fisiología , Ejercicio Físico/fisiología , Lateralidad Funcional/fisiología , Adolescente , Niño , Femenino , Humanos , Masculino
8.
J Chem Theory Comput ; 16(1): 211-223, 2020 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-31816237

RESUMEN

We extend the range-separated double-hybrid RSH+MP2 method (Ángyán, J. G.; et al. Phys. Rev. A 2005, 72, 012510), combining long-range HF exchange and MP2 correlation with a short-range density functional to a fully self-consistent version using the optimized-effective-potential technique in which the orbitals are obtained from a local potential including the long-range HF and MP2 contributions. We test this approach, that we name RS-OEP2, on a set of small closed-shell atoms and molecules. For the commonly used value of the range-separation parameter µ = 0.5 bohr-1, we find that self-consistency does not seem to bring any improvement for total energies, ionization potentials, and electronic affinities. However, contrary to the non-self-consistent RSH+MP2 method, the present RS-OEP2 method gives a LUMO energy which physically corresponds to a neutral excitation energy and gives local exchange-correlation potentials which are reasonably good approximations to the corresponding Kohn-Sham quantities. At a finer scale, we find that RS-OEP2 gives largely inaccurate correlation potentials and correlated densities, which points to the need of further improvement of this type of range-separated double hybrids.

9.
Percept Mot Skills ; 125(3): 612-625, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29764332

RESUMEN

This study sought to determine differences in fencers' visual perceptions during duels (preparatory actions) with right- versus left-handed opponents. Participants were 12 top-ranking right-handed female foil fencers (aged 16-30 years, M = 20.86, SD = 4.76) taking part in a training camp. Testing employed SensoMotoric Instruments Eye Tracking Glasses (SMI ETG 2.0) with eye-tracking analyses covering the visual attention time devoted to various areas of the opposing fencer's body (areas of interest), average fixation, number of glances, and number of fixations during preparatory actions in duels. Each test was conducted during preparatory actions in 20-second staged duels, first against a right-handed, and then against a left-handed opponent. Against left-handed (vs. right-handed) opponents, fencers spent significantly more time looking at and significantly more often fixated on the armed hand. When fighting against right-handed (vs. left-handed) opponents, fencers devoted more time and fixated more often on the opponent's upper torso. These results may point to an interesting phenomenon in which left-handed fencers benefit from weaker strategies adopted by their right-handed opponents who may fixate on the forearm and arm of the weapon hand.


Asunto(s)
Atención/fisiología , Fijación Ocular/fisiología , Lateralidad Funcional/fisiología , Deportes/fisiología , Percepción Visual/fisiología , Adolescente , Adulto , Femenino , Humanos , Adulto Joven
10.
J Sports Med Phys Fitness ; 58(9): 1368-1374, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28738669

RESUMEN

BACKGROUND: A high level of motor coordination (with an emphasis on the accuracy of hand movements) is an important part of fencers' training. Research on motor coordination shows that both hemispheres of the brain are involved in controlling the action of each of the upper limbs. As the physical training of one hand is believed to significantly increase the performance of the other (untrained) hand, the authors attempt to verify the hypothesis that specialized training of the non-dominant limb can improve the performance of the dominant hand in fencing. METHODS: The study was carried out in Poznan, Poland, in 2015 and involved the experimental (N.=8) and control (N.=8) groups of cadets (12.7±0.5 years old); body mass 38.69±4.08; body height 153.47±6.17), who were randomly selected from fencers belonging to the Fencing Club "Warta" in Poznan, Poland. Participants in the study belonged to one training group with a similar training experience of about 6 years. All participants in the study (N.=16) declared right-handedness during trainings and duels. Their right lateralization was also confirmed in a survey, which was conducted using the Edinburgh Questionnaire. The experimental training program included six weeks of specialized training of the coordination skills of the non-dominant side. It was carried out five times a week. Each session took 30 minutes. The aim of the study was to determine the effect of transfer (interhemispheric) training with the use of the non-dominant hand in particular, on the performance of the dominant hand in fencing. RESULTS: The results indicate that the transfer (interhemispheric) training reduced test accomplishment time in tasks performed with the right upper limb during accuracy tests. The procedures applied in the study also reduced test accomplishment time in tasks performed with the left upper limb. CONCLUSIONS: The study demonstrates that an interhemispheric training program can effectively improve the accuracy of fencing actions, at least in the early stages of training.


Asunto(s)
Rendimiento Atlético/fisiología , Ejercicio Físico/fisiología , Lateralidad Funcional/fisiología , Destreza Motora/fisiología , Adolescente , Brazo/fisiología , Estudios de Casos y Controles , Niño , Femenino , Mano/fisiología , Humanos , Masculino , Encuestas y Cuestionarios
11.
Chir Narzadow Ruchu Ortop Pol ; 76(1): 41-6, 2011.
Artículo en Polaco | MEDLINE | ID: mdl-21850997

RESUMEN

AIM: The aim of this study is to find weak link or links of musculoskeletal system (locoutor system) occurred in fencers' body diagnosed by Performance Matrix Tests. ANALYSIS: The particular aim of this research is to estimate: if some weak links occur in a fencers' group, if all fencers in a group have the same weak links, if there is a correlation between weak links and training period length and if there is a connection between weak links and fencers' age. MATERIALS AND METHODS: Our research covered 14 f female and 14 male fencers from the Fencing Section at the Warta Club from Poznan. An average age of fencers was 13.81 +/- 2.84.Performance Matrix Test was used there as a research tool, due to which the presence of musculoskeletal system's weak links was measured. CONCLUSION: The obtained results allow us to formulate the following conclusions: weak links of musculoskeletal system occur in a fencers' group, but it can not be given the exact answer if all fencers suffer from the same weak links. The research has not shown any evidences that there is a correlation between training period length and a number of weak links. Fencers' examination has not confirmed any correlations between fencers' age and the number of weak links. The tests have indicated that the most weak links appeared in a group of 12 years old fencers. Performance Matrix Tests are an easy and cheap tool for diagnosis of musculoskeletal system's weak link appearance. The early diagnosis of weak link/links can protect the fencer from musculoskeletal system's injuries. A lot of weak links found in fencers point out the need for undertaking work on local and global stabilization within a trunk and distal joints.


Asunto(s)
Rendimiento Atlético/fisiología , Fuerza de la Mano/fisiología , Músculo Esquelético/fisiología , Análisis y Desempeño de Tareas , Adolescente , Niño , Femenino , Humanos , Masculino , Enfermedades Musculoesqueléticas/diagnóstico , Fenómenos Fisiológicos Musculoesqueléticos , Polonia , Valores de Referencia , Medicina Deportiva
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