Diurnal Variation in Mental Activities of French Pupils and Influence of Test Protocol

The aim of the study was to determine the influence of the test protocol (individual vs. group) on the diurnal variations in mental activity of 18 11-year-old pupils. Number cancellation, a spatial orientation test, and mathematical problems were tested four times on three successive Fridays at 08:45, 11:15, 13:45 and 16:45 h. On the first and third Fridays the tests were performed on the group of subjects, whereas individual subjects were tested on the second Friday. Results indicated a possible influence of the test protocol (individual vs. group) on intellectual rhythmicity. Only in the group protocol did we find the psychological profile which is normally observed, namely, a performance increase during the morning, a postlunch fall, and then an increase in the afternoon. We suggest the existence of some group effect in these performance tests.     

Diurnal Variation in Heart Rate Variability before and after Maximal Exercise Testing

As heart-rate variability (HRV) is under evaluation in clinical applications, the authors sought to better define the interdependent impact of age, maximal exercise, and diurnal variation under physiologic conditions. The authors evaluated the diurnal changes in HRV 24-h pre- and post-maximal aerobic exercise testing to exhaustion in young (19–25 yrs, n?=?12) and middle-aged (40–55 yrs, n?=?12) adults. Subjects wore a portable 5-lead electrocardiogram holter for 48?h (24?h prior to and following a maximal aerobic capacity test). Time-, frequency-, time-frequency-, and scale-invariant-domain measures of HRV were computed from RR-interval data analyzed using a 5-min window size and a 2.5-min step size, resulting in a different set of outputs every 2.5?min. Results were averaged (mean?±?SE) over four prespecified time periods during the morning, afternoon, evening, and night on Day 1 and Day 2. Diurnal changes in HRV in young and middle-aged adults were compared using a two-way, repeated-measures analysis of variance (ANOVA). Young adults demonstrated higher HRV compared to middle-aged adults during periods of wakefulness and sleep prior to maximal exercise stress testing (i.e., high-frequency power during Day 1: young adults: morning 1862?±?496?ms², afternoon 1797?±?384?ms², evening 1908?±?431?ms², and night 3202?±?728?ms²; middle-aged adults: morning 341?±?53?ms², afternoon 405?±?68?ms², evening 469?±?80?ms², and night 836?±?136?ms²) (p < .05). Exercise resulted in reductions in HRV such that multiple measures of HRV were not significantly different between age groups during the afternoon and evening periods. All measures of HRV demonstrated between-group differences overnight on Day 2 (p < .05). Young adults are associated with higher baseline HRV during the daytime. Sleep increases variability equally and proportionally to daytime variability. Given the higher baseline awake HRV and equal rise in HRV during sleep, the change in HRV from sleep to morning with exercise is greater in younger subjects. These physiologic results have clinical significance in understanding the pathophysiology of altered variability in ill patients. (Author correspondence: aseely@ohri.ca)     

Human Core Temperature Responses during Exercise and Subsequent Recovery: An Important Interaction between Diurnal Variation and Measurement Site

Chronobiological investigations into core temperature during and after exercise can involve ambulatory measurements of intestinal temperature during actual competitions, esophageal temperature measurements in laboratory simulations, or rectal temperature, which can be measured in both the field and laboratory. These sites have yet to be compared during both morning and afternoon exercise and subsequent recovery. At 08∶00 and 17∶00 h, seven recreationally active males exercised at 70% peak oxygen uptake for 30 min and then recovered passively for 30 min. During the experiment, esophageal, rectal, intestinal, and skin temperatures, plus sweat loss, heart rate, and ratings of perceived exertion (RPE), were monitored. We found that the diurnal variation in intestinal temperature responses (0.45±0.32°C; mean±SD) was significantly larger compared with rectal (0.33±0.24°C) and, particularly, esophageal temperature responses (0.21±0.20°C; p= 0.019). This reflected a greater difference of 0.25–0.40°C between the esophagus and the other two sites in the afternoon, compared to inter‐site differences of only 0.13–0.16°C in the morning. Diurnal variation was small for skin temperature, heart rate, sweat loss, and RPE responses during exercise (p>0.05). Our data suggest that the relative differences between intestinal, rectal, and esophageal temperature during exercise and subsequent recovery depend on time of day to the extent that inferences from studies on experimental and applied chronobiology will be affected.     

Effect of Pedal Rate on Diurnal Variations in Cardiorespiratory Variables

Recently, it was observed that the freely chosen pedal rate of elite cyclists was significantly lower at 06:00 than at 18:00 h, and that ankle kinematics during cycling exhibits diurnal variation. The modification of the pedaling technique and pedal rate observed throughout the day could be brought about to limit the effect of diurnal variation on physiological variables. Imposing a pedal rate should limit the subject's possibility of adaptation and clarify the influence of time of day on physiological variables. The purpose of this study was to determine whether diurnal variation in cardiorespiratory variables depends on pedal rate. Ten male cyclists performed a submaximal 15 min exercise on a cycle ergometer (50% W_max). Five test sessions were performed at 06:00, 10:00, 14:00, 18:00, and 22:00 h. The exercise bout was divided into three equivalent 5 min periods during which different pedal rates were imposed (70 rev · min^?1, 90 rev · min^?1 and 120 rev · min^?1). No significant diurnal variation was observed in heart rate and oxygen consumption, whatever the pedal rate. A significant diurnal variation was observed in minute ventilation (p=0.01). In addition, the amplitude of the diurnal variation in minute ventilation depended on pedal rate: the higher the pedal rate, the greater the amplitude of its diurnal variation (p=0.03). The increase of minute ventilation throughout the day is mainly due to variation in breath frequency (p=0.01)—the diurnal variation of tidal volume (all pedal rate conditions taken together) being non‐significant—but the effect of pedal rate×time of day interaction on minute ventilation specific to the higher pedal rate conditions (p=0.03) can only be explained by the increase of tidal volume throughout the day. Even though an influence of pedal rate on diurnal rhythms in overall physiological variables was not also evidenced, high pedal rate should have been imposed when diurnal variations of physiological variables in cycling were studied.     

Diurnal Variation in Wingate-Test Performance and Associated Electromyographic Parameters

The present study was designed to evaluate time-of-day effects on electromyographic (EMG) activity changes during a short-term intense cycling exercise. In a randomized order, 22 male subjects were asked to perform a 30-s Wingate test against a constant braking load of 0.087?kg·kg^?1 body mass during two experimental sessions, which were set up either at 07:00 or 17:00?h. During the test, peak power (P_peak), mean power (P_mean), fatigue index (FI; % of decrease in power output throughout the 30 s), and evolution of power output (5-s span) throughout the exercise were analyzed. Surface EMG activity was recorded in both the vastus lateralis and vastus medialis muscles throughout the test and analyzed over a 5-s span. The root mean square (RMS) and mean power frequency (MPF) of EMG were calculated. Neuromuscular efficiency (NME) was estimated from the ratio of power to RMS. Resting core temperature, P_peak, P_mean, and FI were significantly higher (p?<?.05) in the evening than morning test (e.g., P_peak: 11.6?±?0.8 vs. 11.9?±?1 W·kg^?1). The results showed that power output decreased following two phases. During the first phase (first 20s), power output decreased rapidly and values were higher (p?<?.05) in the evening than in the morning. During the second phase (last 10s), power decreased slightly and appeared independent of the time of day of testing. This power output decrease was paralleled by evolution of the MPF and NME. During the first phase, NME and MPF were higher (p <?.05) in the evening. During the second phase, NME and MPF were independent of time of day. In addition, no significant differences were noticed between 7:00 and 17:00?h for EMG RMS during the whole 30 s. Taken together, these results suggest that peripheral mechanisms (i.e., muscle power and fatigue) are more likely the cause of the diurnal variation of the Wingate-test performance rather than central mechanisms. (Author correspondence: n_souissi@yahoo.fr)     

Diurnal Variation in the Function of Serotonin Terminals in the Rat Hypothalamus

The high-affinity binding of [3H]imipramine is associated with the serotonin (5-hydroxytryptamine; 5-HT) transporter in the brain and in platelets. In the rat hypothalamus it has been reported that the density of these sites is increased in the dark period of the day, and this could result in an alteration in the release of 5-HT. The electrically evoked release of [3H]5-HT was thus studied in preloaded hypothalamic slices prepared from rats kept under 12:12 h light/dark or dark/light schedules. The fractional release of [3H]5-HT evoked by electrical stimulation, but not by the 5-HT releasing agent fenfluramine, was significantly decreased during the dark period when compared with the light period. The effects of the 5-HT reuptake blocker citalopram, of the two 5-HT autoreceptor agonists 5-methoxytryptamine and RU 24969, and of the 5-HT autoreceptor antagonist methiothepin on the release of [3H]5-HT were the same in both groups of rats. In conclusion, the release of [3H]5-HT from prelabelled rat hypothalamic slices is decreased during the dark period of the day. This modification is not reflected by changes in the effects of citalopram, an inhibitor of 5-HT reuptake, to modify the overflow of [3H]5-HT. The sensitivity and efficacy of agonists of the 5-HT autoreceptor are the same during the light and dark periods of the day.     

Diurnal light curves and landscape-scale variation in photosynthetic characteristics of Thalassia testudinum in Florida Bay

When using pulse-amplitude modulated (PAM) fluorometry to measure landscape-scale photosynthetic characteristics, diurnal variations in fluorescence during sampling may confound the assessment of the physiological condition. In this study, two photophysiological assessment techniques: Diurnal Yield and Diurnal Rapid Light Curve (RLC) were investigated in an attempt to incorporate the temporal and spatial scales of sampling into a physiological assessment of Thalassia testudinum in Florida Bay. Photosynthesis–irradiance (P–E) curves were calculated using both methods and the ability of each to predict the relationship between relative electron transport rates and irradiance was assessed. Both methods had limitations in providing consistent estimates of photosynthetic efficiency or capacity. The Diurnal Yield method produced unrealistically high predictions of photosynthetic capacity (relative electron transport rate (rETR_max), 417–1715) and saturation irradiance (I_k, 1045–4681 μmol photons m⁻² s⁻¹). In contrast, the Diurnal RLC method generally produced predictions of rETR_max (100–200) and I_k (300–500 μmol photons m⁻² s⁻¹) which were similar to average values calculated from each day's RLCs. The Diurnal RLC method was unable to predict photosynthetic efficiency () only when ambient irradiances were continuously >I_k during the sampling period. We believe that with sampling modifications in high-light or shallow environments, such as starting sampling earlier in the morning, extending sampling later in the day, or using the average from each day's RLCs, that the Diurnal RLC method can produce representative estimates of rETR_max, , and I_k, providing a method to characterize seagrass photosynthesis at the landscape-level. The Diurnal RLC method does not negate Diurnal variation but it produces a curve that incorporates the changing ambient light environment into the assessment of seagrass physiological status.     

番茄叶片糖与转化酶的日变化研究

为探讨转化酶在叶片糖分含量和光合作用日变化中的作用,测定了番茄(Lycopersicon esculentumL.)叶片光合速率、转化酶活性、淀粉、蔗糖、葡萄糖和果糖含量,并分别分析了12:00前后它们间的相关关系.结果表明:番茄日间叶片净光合速率在10:00和16:00出现一大一小两个高峰;6:00~18:00叶片中淀粉和果糖呈现持续升高,而蔗糖和葡萄糖为先升后降趋势;光合速率同叶片蔗糖含量和胞质转化酶活性存在高度正相关,淀粉和果糖含量同光合速率未表现出显著相关性.由此可知,胞质转化酶在蔗糖代谢方面有明显的作用;果糖可能是通过抑制胞壁转化酶活性,促进了蔗糖外运.     

Diurnal Variation in the Symptoms of Colds and Influenza

The present research examined diurnal variation in the severity of symptoms of experimentally-induced colds and influenza. Nasal secretion was greatest in the morning, decreased over the day, and then showed a slight increase in the late evening. Colds did not change the average temperature, nor did they alter the temperature rhythm. Similar, negative results were found with alertness ratings.

Influenza B illnesses produced an increase in nasal secretion and systemic effects. The average temperature increased during this illness and subjects reported that they felt more drowsy. Diurnal variation in the severity of local and central symptoms was observed, with nasal secretion and the temperature increase being greatest in the early morning. These results have important implications for the assessment and treatment of the illnesses.     

Diurnal Variation in the Symptoms of Colds and Influenza

The present research examined diurnal variation in the severity of symptoms of experimentally-induced colds and influenza. Nasal secretion was greatest in the morning, decreased over the day, and then showed a slight increase in the late evening. Colds did not change the average temperature, nor did they alter the temperature rhythm. Similar, negative results were found with alertness ratings.

Influenza B illnesses produced an increase in nasal secretion and systemic effects. The average temperature increased during this illness and subjects reported that they felt more drowsy. Diurnal variation in the severity of local and central symptoms was observed, with nasal secretion and the temperature increase being greatest in the early morning. These results have important implications for the assessment and treatment of the illnesses.     

Diurnal variation in physical-chemical properties and primary production in the interconnected marine,mangrove and freshwater biotopes of Kakinada coast,Andhra Pradesh,India

Diurnal variation in hydrological variables and dissolved inorganic nutrients such as PO _inf4 ^sup3– -P, N O _inf2 ^sup– -N, NO _inf3 ^sup– -N and NH _inf4 ^sup+ -N were studied in three interconnected biotopes including freshwater, marine and mangrove brackish water of the Kakinada coastal zone, Andhra Pradesh. Samples were collected at intervals of 3 hours, for a period of 24 hours. In the marine environment salinity varied from 26 to 32 whereas in the mangrove waters it fluctuated from 12 to 20 and in both biotopes salinity showed bimodal type of oscillation. Dissolved oxygen content was high in the mangrove waters during day time but decreased rapidly during the night hours. In the marine environment PO_f4 ^p3–-P concentration varied from 0.345 to 1.195 g at l^–1, NO _inf3 ^sup– -N from 1.03 to 6.62 g at l^–1 and NO _inf2 ^sup– -N from 0.086 to 0.506 g at l^–1. The highest and the lowest concentrations of PO _inf4 ^sup3– -P, NO _inf3 ^sup– -N, NO _inf2 ^sup– -N recorded in the mangrove waters were 0.790 and 0.325 g at l^–1, 7.10 and 1.60 g at l^–1 and 0.278 and 0.060 g at l^–1, respectively. The concentration of PO _inf4 ^sup3– -P, NO _inf3 ^sup– -N and NO _inf2 ^sup– -N were high in the freshwater canal, the maximum and minimum values being 1.110 and 0.730 g at l^–1, 26.40 and 9.98 g at l^–1 and 0.520 and 0.252 g at l^–1 respectively. The concentration of ammonia was relatively high in the mangrove water. Gross and net primary production in the mangrove water was 4 times higher than in the marine biotope. There was no export of dissolved nutrients from the mangrove environment to the adjacent marine waters.     

Diurnal, seasonal and sex variations in rectal temperature of African giant rats (Cricetomys gambianus, Waterhouse)

(1)

Rectal temperature (T_r) was measured in captive African giant rats (Cricetomys gambianus, Waterhouse), live-trapped in the Savannah during the harmattan, hot-dry and rainy seasons with the aim of determining diurnal, seasonal and sex patterns.

(2)

Mean (±SEM) T_r in the morning (37.16±0.04 °C) was lower (P<0.001) than the afternoon (37.49±0.03 °C) and evening (37.66±0.03 °C). There was no significant difference (P>0.05) between afternoon and evening T_r during the harmattan and rainy seasons, but the difference was significant (P<0.001) during the hot-dry season. Overall T_r was higher (P<0.001) during the hot-dry (38.03±0.03 °C) than harmattan (37.17±0.03 °C) and rainy (37.21±0.03 °C) seasons. T_r of bucks was lower than that of does (P<0.0001) during the harmattan and rainy seasons, but sex difference during the hot-dry season was not significant (P>0.05).

(3)

Base-line T_r values for the African giant rats are shown for the first time. Season, time of day and sex influence fluctuations in T_rs of African giant rats, and should be considered during diagnostic and clinical evaluations.

     

Variation in the temperature preference and growth rate of individual fish reconciles differences between two growth models

1. A growth model, originally developed for brown trout (Salmo trutta), has now been fitted to data for Atlantic salmon (S. salar) and stone‐loach (Barbatula barbatula) from English populations, and Arctic charr (Salvelinus alpinus) from Sweden. The model relates growth rate to temperature for a fish of standard size and the functional relationship has a triangular shape with a sharp peak at the optimal temperature for growth and zero growth at the base of the triangle. It was unsuitable for growth data for Norwegian salmon, and a curvilinear Ratkowsky model provided a better fit, though the experimental protocol was different in the Norwegian and English experiments. 2. The Norwegian salmon were kept in groups in each tank, had to compete for food, and had to be divided into slow, moderate and fast growers before the Ratkowsky model could be fitted. Each English salmon was kept in its own tank and fed individually. For replicate experiments, fish of similar size were selected. Variation among fish kept under similar conditions was therefore small, and the triangular model was essentially for individual fish, not groups of fish. 3. The present simulation study tests the hypothesis that individual differences in the growth response could account for the curvilinear growth‐temperature relationship for the Norwegian salmon. The triangular model was used to generate the growth response to temperature for a group of salmon, each fish having a slightly different temperature preference and growth rate. The result was a curvilinear response, well approximated by the Ratkowsky model (adjusted R² = 0.96). When the variability in individual temperature preference was increased, the Ratkowsky model was an even better fit (adjusted R² = 0.98). Therefore, the apparent discrepancy between the two models was reconciled by allowing for individual differences in temperature preference and growth rate within groups of fish.     

Seasonal Variation in Amount of Unabsorbed Dietary Carbohydrate from the Intestine after Breakfast in Japanese Subjects

We previously showed that daytime dim‐light exposure has a negative effect on the efficiency of dietary carbohydrate absorption in the evening, whereas evening‐time dim‐light exposure has a beneficial effect. These results suggest that seasonal changes in the environmental light may affect gastrointestinal activity, and that there might, therefore, be seasonal variation in the efficiency of dietary carbohydrate absorption from the intestine. In order to prove this hypothesis, we measured the amount of dietary carbohydrate unabsorbed from the intestine after a breakfast in healthy female Japanese subjects during the four seasons of the year. We estimated the amount of unabsorbed dietary carbohydrate by the breath hydrogen test, which measures the amount of hydrogen in exhaled air. A 6 g solution of lactosucrose, an indigestible trisaccharide, was used for comparison. Two groups of subjects, 12 subjects in Osaka and 14 subjects in Nagano, were studied in the winter (January to February), spring (April to May), summer (July to August), and autumn (October to November) of 2004. We found the following results: (1) In no season were there any significant differences between the two subgroups in the orocecal transit time of the breakfast and the lactosucrose solution. Nor were there any significant differences in the amount of unabsorbed dietary carbohydrate from the breakfast. (2) Using the pooled data of the total of 26 subjects, there was no significant seasonal variation in the orocecal transit time of the breakfast or the lactosucrose solution. (3) There was a significant seasonal variation in the amount of unabsorbed dietary carbohydrate from the breakfast. (4) The amount of unabsorbed dietary carbohydrate from the breakfast was largest in winter and smallest in autumn. Results in spring and in summer were similar and intermediate between those in winter and autumn. Post hoc multiple comparison tests showed that the amount of unabsorbed dietary carbohydrate in winter was significantly larger than in autumn. (5) In winter, the average ratio of the amount of unabsorbed dietary carbohydrate to the total amount of carbohydrate in the breakfast was about 12%; in autumn it was about 6%. These results clearly show that there is seasonal variation in the efficiency of intestinal dietary carbohydrate absorption among young female Japanese subjects.     

Variation in primate decision-making under uncertainty and the roots of human economic behaviour

Uncertainty is a ubiquitous component of human economic behaviour, yet people can vary in their preferences for risk across populations, individuals and different points in time. As uncertainty also characterizes many aspects of animal decision-making, comparative research can help evaluate different potential mechanisms that generate this variation, including the role of biological differences or maturational change versus cultural learning, as well as identify human-unique components of economic decision-making. Here, we examine decision-making under risk across non-human primates, our closest relatives. We first review theoretical approaches and current methods for understanding decision-making in animals. We then assess the current evidence for variation in animal preferences between species and populations, between individuals based on personality, sex and age, and finally, between different contexts and individual states. We then use these primate data to evaluate the processes that can shape human decision-making strategies and identify the primate foundations of human economic behaviour.This article is part of the theme issue ‘Existence and prevalence of economic behaviours among non-human primates’.     

Effect of time of day on the offensive capability and aerobic performance in football game

The purpose of this study was to examine the time-of-day effects on the offensive capability and aerobic performance in football game in young subjects. In a randomized order, participants realized the Yo–Yo intermittent recovery test in two test sessions and a football game situations (two 15-min games), interspersed by a verbalization sequence (3 min) at 08:00 and 17:00 h on separate days. A recovery period of 24 h was permitted between two consecutive test sessions. The results revealed diurnal variations on the maximal aerobic velocity during the Yo–Yo test (MAV) and the oral temperature with higher values in the afternoon than morning (p < 0.05). Concerning offensive capability, the numbers of scored goals were significantly higher at 17:00 h in comparison with 08:00 h (p < 0.05). However, there was no significant difference between 08:00 and 17:00 h for the kicked balls (shooting parameter). In conclusion, our findings suggest that performance was improved in the evening and the parameters (shooting and Scored goals) can be used as a model to describe the offensive capacity in football game depending on the time of day.     

Seasonal Variation in the Amount of Dietary Carbohydrate Not Absorbed from the Intestine after Breakfast in Elderly Japanese Females

It was previously shown that there is seasonality in the amount of dietary carbohydrate not absorbed from the intestine after breakfast, the amount of carbohydrate in winter being significantly larger than that in autumn in young Japanese subjects. In order to investigate this phenomenon further, the experiment was repeated on 22 elderly Japanese female subjects (61–78 yrs of age) during the four seasons of the year. The amount of unabsorbed dietary carbohydrate by the breath hydrogen test, which measures the amount of hydrogen in exhaled air, was then esitmated. A 6 g solution of lactosucrose, an indigestible trisaccharide, was used for comparison. Two groups of subjects, 16 subjects in Osaka and 6 subjects in Nagano, were studied in the summer (July to August) and autumn (October to November) of 2005 and the winter (January to February) and spring (April to May) of 2006. The following results were found using the pooled data of the total of 22 subjects. With regard to the amount of breath hydrogen excretion of the lactosucrose solution, there was no significant difference between the four seasons. There was a significant seasonal change in the efficiency of dietary carbohydrate absorption from the intestine after breakfast. The percentage of total carbohydrate that was not absorbed was lowest in the spring and highest in the winter. A comparison of the results from studies on the elderly and young subjects revealed the percentage of total carbohydrate that was not absorbed in the elderly was significantly lower than in the young in the winter, spring, and summer. These results indicate that there is seasonal variation in the efficiency of dietary carbohydrate absorption from the intestine among elderly female Japanese subjects as well as young female Japanese subjects. They also suggest that the efficiency of dietary carbohydrate absorption from the intestine after breakfast is retained in these naturally active and healthy elderly subjects.     

内蒙古达赉湖地区蒙原羚昼间行为时间分配

2007年11月～2008年9月,在内蒙古达赉湖地区采用扫描取样法共对404只次蒙原羚Procapra gutturosa成年个体进行了19 385 min (323.1 h) 的昼间行为时间分配观察,将蒙原羚的行为分为采食、站立、移动、卧息、繁殖和其他等6类.结果 表明:蒙原羚晨昏各有一个采食高峰,在12:00前后还会发生1～2次采食小高峰.卧息常发生在采食高峰后,在晨昏所占比例低.单因素方差分析显示蒙原羚春夏秋冬采食、站立、移动、卧息和其他行为的时间分配均存在显著差异,这表明蒙原羚的行为时间分配有较大弹性,从而适应变化的环境.     

Orthogonal Test Design for Optimization of the Extraction of Polysaccharides from Inonotus cuticularis and Their Antioxidant Activities

Medical fungi polysaccharides belong to a very important species of biological macromolecules, which are the basic substances that effectively maintain and ensure the normal operation of biological life activities. However, research on extraction and biological activity of Inonotus cuticularis polysaccharides has never been reported. In this study, the optimum yield of Inonotus cuticularis polysaccharides was determined by the orthogonal experimental design. The highest yield of 3.10±0.06 % was obtained with extraction temperature of 80 °C, extraction time of 150 min, and water to raw material ratio of 30 mL/g and repeated twice. After deproteinization for 5 times, the protein removal rate reached 70.10±1.75 %, and the content of polysaccharides and protein were 46.64 and 0.42 %. Infrared spectrometer indicated that Inonotus cuticularis polysaccharides are typical β‐pyranose with characteristic peaks of polysaccharides. Subsequently, the activities of scavenging free radicals for the deproteinated polysaccharides were studied. When the concentration of Inonotus cuticularis polysaccharides was 0.3 mg/mL, the scavenging activities of the sample on DPPH^., ^.OH, ABTS^.+ and O₂^.? reached 83.67±0.27, 65.21±4.82, 43.45±1.36 and 80.28±2.30 %, respectively, and the reducing power reached 0.46±0.01. The IC₅₀ values scavenging DPPH^., ^.OH, ABTS^.+ and O₂^.? were 0.139±0.13, 0.162±0.14, 0.317±0.30 and 0.121±0.10 mg/mL, respectively. Results showed that Inonotus cuticularis polysaccharides present potential stronger antioxidant activities, especially ^.OH scavenging activity and reducing power. Experimental results could provide research basis of Inonotus cuticularis polysaccharides for further exploitation and utilization.     

Blocks and bodies: sex differences in a novel version of the Mental Rotations Test

A novel version of the Mental Rotations Test (MRT) that alternated the standard block figures with three-dimensional human figures was administered to 99 men and 129 women. Women and men differed predictably in their retrospective reports of childhood play and digit ratios, a putative measure of prenatal androgen action. Compared to the block figure items, human figure items on the modified MRT were associated with an improvement in performance in both sexes. However, consistent with the study hypothesis, the enhancing effect of the human figure condition on performance as measured by conventional scores was smaller in men compared to women and not at all evident in men when performance was measured by ratio scores. A closer inspection of the human figures effects on test scores showed performance in women improved for both male and female figure items. In contrast, relative to scores on block figure items, performance in men improved when stimuli were male figures but did not improve when stimuli were female figures. These results add to the evidence that the magnitude of sex differences in scores on the MRT may vary according to the test content and item properties. The findings suggest that online measures of cognitive processing in response to different classes of test stimuli (e.g., animate vs. inanimate objects, self-relevant vs. neutral stimuli) may prove useful in research aimed at understanding the hormonal and social factors contributing to the sex difference in performance on the MRT.