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Learning is one of the activities that can be managed in education, with this discussion entitled Creative Learning Methods Through Educational Game Tools in Forming Early Childhood Character, we can make learning in education more creative so that students do not experience boredom in following the learning process given. Creative learning methods through educational play tools in shaping early childhood character, can help character formation of students in education levels ranging from kindergarten, elementary, junior high, high school and up to higher education, as for the educational game tool in question is a game tool that can be played without any burden for students and can be enjoyed by those entering the adult level. With this creative learning method through educational play tools in shaping early childhood character, it can be enjoyed when they enter adolescence and adulthood, because interesting learning will always be remembered and can be applied various kinds of learning models that can foster children's creative power, so that patterns think children are getting more advanced and modern.

The research hypothesis starts from the premise that the level of adult body fat positively influences the possibility of practising physical exercise by the adult population, by maintaining an optimal level of physical condition. The object of the research is the model of growth and development of the adult, FEFSM students from the final year. The purpose of the research is the model of growth and development by analysing the body fat of adults, FEFSM students in accordance with the ability to have an optimal level of the specific physical condition. The practical value of the research is given by the possibility of developing growth and development models for adults.

Both training volume and overall physical activity (PA) play a role in young athletes’ sports performance and athletic development. The purpose of this study was to describe the training volume and PA of young athletes in endurance, aesthetics, ball games, and power sports. Questionnaire data (n = 671) were obtained from 15-year-old Finnish athletes on sports participation, along with accelerometer data (n = 350) assessing the amount and intensity of their PA. The athletes’ mean weekly training volume was 11 h 41 min. Objectively assessed PA amounted to 4 h 31 min daily, out of which 1 h 31 min was at a level of moderate-to-vigorous intensity (MVPA). Among 24% of the athletes, the weekly training volume (in hours) exceeded the recommended level of age-in-years, which might increase their risk of sports injuries. At the same time, one in six athletes (16%) did not—on average—reach the internationally recommended threshold level of at least 60 minutes of MVPA per day. Compared to girls, boys averaged 2.5 more hours of training per week, and had 21 more minutes of MVPA per day. Moreover, boys had a higher goal orientation than girls, with 52% of the boys and only 29% of the girls focused on success at adult level. Although total training volume and PA did not differ among sports types, there were differences in training forms, and in the proportions of MVPA. The young athletes were found to vary greatly in training forms, training volumes, MVPA, and goal orientation; hence, training should be planned individually, both for team sports and individual sports. peerReviewed

The period of emancipation in seabirds, when juveniles change from a terrestrial existence to a life at sea, is associated with many challenges. Apart from finding favourable foraging sites, they have to develop effective prey search patterns and physiological capacities that enable them to capture sufficient prey to meet their energetic needs. Animals that dive to forage, such as king penguins (Aptenodytes patagonicus), need to acquire an adequate breath-hold capacity, allowing them to locate and capture prey at depth. To investigate the ontogeny of their dive capacity and foraging performance, we implanted juvenile king penguins before their first departure to sea and also adult breeders with a data-logger recording pressure and temperature. We found that juvenile king penguins possess a remarkable dive capacity when leaving their natal colony, enabling them to conduct dives in excess of 100 m within their first week at sea. Despite this, juvenile dive/foraging performance, investigated in relation to dive depth, remained below the adult level throughout their first year at sea, probably reflecting physiological limitations as a result of incomplete maturation. A significantly shallower foraging depth of juveniles, particularly during their first 5 months at sea, could also indicate differences in foraging strategy and targeted prey. The initially greater wiggle rate suggests that juveniles fed opportunistically and also targeted different prey from adults and/or that many of the wiggles of juveniles reflect unsuccessful prey-capture attempts, indicating a lower foraging proficiency. After 5 months, this difference disappeared, suggesting sufficient physical maturation and improvement of juvenile foraging skills.

Effective time-motion analysis can provide information directly applicable to the design of physical conditioning and testing programmes. The aim of the present study was to determine the external output of female beach volleyball players during tournament match-play and to assess the effect of competition level, margin of score differential and alterations of external output within matches. The external output profile of ten adult level (age 27 ± 3 y) and ten under 23 (‘U23’; age 19 ± 2 y) female beach volleyball players were determined using GPS technology (10 Hz) during 60 matches (n = 50 first and second sets and 20 third sets files) played during their respective Australian Beach Volleyball Championship tournaments. Comparisons between groups and the influence of contextual factors on the external output within matches were analysed using linear mixed models. Adult beach volleyball players covered a greater relative distance (i.e., m·min-1) in speed zone 2 (1.0-1.99 m·s-1; 42.0% of total relative distance) and zone 3 (≥2.0 m·s-1; 10.9% of total relative distance) compared to U23 players. Relative distance, mean acceleration/deceleration and the relative distance covered in acceleration zone 2 and deceleration zone 2 and 3 was greater in set 1 compared to set 2. Sets that were decided by smaller score margins (5-point score differential). The findings from this study suggest that there are contextual factors that influence the speed and acceleration/deceleration profile of female beach volleyball players such as tournament level, score margin and set-to-set variations that may have implications for the physiological and mechanical requirements of female players preparing for competition.

Objective Report eccentric knee flexor strength values of elite Gaelic football players from underage to adult level whilst examining the influence of body mass and previous hamstring injury. Design Cross-sectional study. Setting Team's training facility. Participants Elite Gaelic football players (n = 341) from under 14 years to senior age-grades were recruited from twelve teams. Main outcome measures Absolute (N) and relative (N·kg −1 ) eccentric hamstring strength as well as corresponding between-limb imbalances (%) were calculated for all players. Results Mean maximum force was 329.4N (95% CI 319.5–340.2) per limb. No statistically significant differences were observed in relative force values (4.4 N ·kg −1 , 95% CI 4.2–4.5) between age-groups. Body mass had moderate-to-large and weak associations with maximum force in youth (r = 0.597) and adult (r =0 .159) players, respectively. Overall 40% (95 CI 31.4–48.7) presented with a maximum strength between-limb imbalance >10%. Players with a hamstring injury had greater relative maximum force (9.3%, 95% CI 7.0–11.8; p > 0.05) and a 28% (95% CI 10.0–38.0) higher prevalence of between-limb imbalances ≥15% compared to their uninjured counterparts. Conclusions Overlapping strength profiles across age-groups, combined with greater strength in previously injured players, suggests difficulties for establishing cut-off thresholds associated with hamstring injury risk.

BackgroundEmergency department (ED) crowding is a critical problem in the delivery of acute unscheduled care. Many causes are external to the ED, but antiquated operational traditions like triage also contribute. A physician intake model has been shown to be beneficial in a single-centre study, but whether this solution is generalisable is not clear. We aimed to characterise the current state of front-end intake models in a national sample of EDs and quantify their effects on throughput measures.MethodsWe performed a descriptive mixed-method analysis of ED process changes implemented by a cross section of self-selecting institutions who reported 2 years of demographic/operational data and structured process descriptions of any ‘new front-end processes to replace traditional nurse-based triage’.ResultsAmong 25 participating institutions, 19 (76%) provided data. While geographically diverse, most were urban, academic adult level 1 trauma centres. Thirteen (68%) reported implementing a new intake process. All were run by attending emergency physicians, and six (46%) also included advanced practice providers. Daily operating hours ranged from 8 to 16 (median 12, IQR 10.25–15.85), and the majority performed labs, imaging and medication administration and directly discharged patients. Considering each site’s before-and-after data as matched pairs, physician-driven intake was associated with mean decreases in arrival-to-provider time of 25 min (95% CI 13 to 37), ED length of stay 36 min (95% CI 12 to 59), and left before being seen rate 1.2% (95% CI 0.6% to 1.8%).ConclusionsIn this cross section of primarily academic EDs, implementing a physician-driven front-end intake process was feasible and associated with improvement in operational metrics.

Background. Latvian sports authorities under the Ministry of Education and Science are the main organisers of the sports life in Latvia. However, they have not been successful in providing equally good support to all athletes who need it. It is especially difficult to receive support for improving skills of individual athletes engaged in team sports. Often it is the individual mastery of an athlete that prohibits them from moving on to the adult level of sports of high achievement, even if the athlete was very talented and one of the best in the country when he/she was young. Methods. The descriptive statistics method and content analysis were used to assess shortcomings in the allocation of finances in the Latvian sports industry. Conclusions were drawn on the data collected, on the basis of which a new method was developed in sports management, the efficiency of which was verified by performing an experiment. Results. After analysing the most popular sports among young people in the country, as well as the available infrastructure, it may be suggested which sports are the most attractive for investors. It may be concluded that the state is able to successfully solve this problem by attracting private investors who would be personally interested in the development of athletes and also carry out successful investment management. The study demonstrated that a successful process of private investments ensures a positive return on the investments, as well as the development of athletes. One way to build successful cooperation is by creating high-quality sports development centres or sports investment management companies which will efficiently contribute to athletes’ transition from youth to professional sports. The efficiency of the methodology developed can be demonstrated by creating a company which would act as an example for attracting private investments in the development of athletes. Conclusion. The development of athletes would become more efficient and purposeful if sports could attract potential investments with promising returns. This would create a tripartite cooperation among the state, athletes and private investors, which would benefit each of the three cooperating parties. Additional funding in the development of Latvian athletes would have a positive impact on the entire sports industry as a whole. Keywords: Latvian sports, private investments, sports funding, massive sports system, investment criteria, high-class sports, sports development, efficient investment management

In human, no studies are available regarding changes in kisspeptin1 receptor (KISS1R) sensitivity during pubertal transition. In this study, healthy boys were classified into 5 Tanner stages of puberty (n=5/stage). Human kisspeptin-10 was administered to boys at each Tanner stage and to adult men (n=5) as an IV bolus for comparison. Serial blood samples were collected for 30 min pre- and 120 min post-kisspeptin injection periods at 30 min interval for measuring plasma LH and testosterone levels. There was insignificant effect of kisspeptin on LH and testosterone levels in boys of Tanner stages I–III. At Tanner stage IV, the effect of kisspeptin on plasma LH was insignificant. However, a paired t-test on a log-transformed data showed a significant (P<0.05) increase in mean peak post-kisspeptin testosterone level. In Tanner stage V, a significant (P<0.05) increase was observed in mean post-kisspeptin peak LH level as compared to the mean basal LH value. Post-kisspeptin plasma testosterone levels were also significantly (P<0.05) increased as compared to the pre-kisspeptin level in Tanner stage V. Our data suggest that sensitivity of KISS1R on GnRH neurons with reference to LH stimulation in boys develops during the later part of puberty reaching to adult level at Tanner stage V. This trial is registered with WHO International Clinical Trial Registration ID NCT03286517.

The physical activity (PA) plays an important role in the fight against the chronic noncommunicable diseases.The objective of this study was to assess the level of physical activity in an adult population in rural and urban area in Côte d'Ivoire. To achieve this goal, a group of 1046 participants was submitted to the Global Physical Activity Questionnaire (GPAQ). The data analysis was done according to the GPAQ guidelines. The prevalence of the recommended level of the physical activity during the work, the leisure and the displacement was calculated.This assessment has showed that the intense Physical Activity (PA) decreased with age, from 34% (19-29 years) to 14% (50-60 years).Then the results have showed that the workers had the highest intensity Physical Activity Level (NAP) at 70%, versus 13% for the office workers.Moreover, more the Level of Study (LS) was higher, more the physical activity practiced decreased, whatever the area of living. Finally, it has been shown that men were more active than women. Also, the level of physical activity was higher in rural than in urban areas, and the limited physical activity level was present in the adult population. This work has shown that the level of physical activity and the contexts of practice vary according to the socio-demographic characteristics. At that fact, targeted interventions to promote the physical activity are necessary.

The aim of this study was to develop a children's version of the Cantonese Hearing in Noise Test (CHINT-C). This was accomplished in two stages. First, a total of 120 sentences understood by children aged 6-7 years were selected from the original pool of CHINT sentences and were grouped into 12 lists, each containing 10 sentences composed of 10 characters. Following this, 260 primary and secondary school children, with ages ranging from 6 to 17 years, and 21 adults of age 18 or older were administered the CHINT-C to determine its reliability/validity, normative data, and age-specific correction factors. The result showed good interlist reliability, and test–retest reliability for the CHINT-C. The speech perception skills assessed using the CHINT-C do not reach adult level until after 11-13 years of age. Correction factors were established that could be used to determine age-specific norms for the evaluation of speech intelligibility of children in various sound fields.

Localization of tactile stimuli to the hand and digits is fundamental to somatosensory perception. However, little is known about the development or genetic bases of this ability in humans. We examined tactile localization in normally developing children, adolescents, and adults and in people with Williams syndrome (WS), a genetic disorder resulting in a wide range of severe visual-spatial deficits. Normally developing 4-year-olds made large stimulus-localization errors, sometimes across digits, but nevertheless their errors revealed a structured internal representation of the hand. In normally developing individuals, errors became exponentially smaller over age, reaching the adult level by adolescence. In contrast, people with WS showed large localization errors regardless of age and a significant proportion of cross-digit errors, a profile similar to that of normally developing 4-year-olds. Thus, tactile localization reflects internal organization of the hand even early in normal development, undergoes substantial development in normal children, and is susceptible to developmental, but not organizational, impairment under genetic deficit.

Normative data on the simple acoustic reaction time were obtained from 56 children without neurological or psychiatric symptoms aged between four and 14 years, and the results were compared with those for an adult reference group. Mean reaction times declined precipitously from 465 msec at age five to 190 msec at 15 years. The relationship between reaction time and age during childhood can be described by a linear equation in a log-log system. The adult level is achieved at 16 years.

Physical and psychological differences related to birthdate amongst athletes of the same selection year have been characterised as the “relative age effects” (RAEs). RAEs have been identified in a variety of sports, both at youth and adult level, and are linked with dropout of athletes and a reduction of the talent pool. This study examined the existence, mechanisms and possible solutions to RAEs using qualitative methodology. Seven experts in the field of talent identification and development were interviewed. Inductive analysis of the data showed that, while there was mixed evidence for the existence of RAEs across sports, the eradication of RAEs was attributed to controllable features of the development environment. The factors reported included the structure of “categories” used to group athletes within the sport (e.g. age, weight, size, skills), recognition and prioritisation of long-term development over “short term win focus.” Education of relevant parties (e.g. coaches, scouts, clubs) about RAEs and the nature of “talent” within a long-term context was suggested, along with careful consideration of the structure of the development environment (e.g. delayed selection, provision for late developers, focus on skills not results, use of challenge). Implications for research and practice are discussed.

We investigated the impact of early childhood and adulthood bilingualism on the attention system in a group of linguistically and culturally homogeneous children (5- and 6-year olds) and young adults. We administered the child Attention Network Test (ANT) to 63 English monolingual and Korean-English bilingual children and administered the adult ANT to 39 language- and culture-matched college students. Advantageous bilingual effects on attention were observed for both children and adults in global processing levels of inverse efficiency, response time, and accuracy at a magnitude more pronounced for children than for adults. Differential bilingualism effects were evident at the local network level of executive control and orienting in favor of the adult bilinguals only. Notably, however, bilingual children achieved an adult level of accuracy in the incongruent flanker condition, implying enhanced attentional skills to cope with interferences. Our findings suggest that although both child and adult bilinguals share cognitive advantages in attentional functioning, age-related cognitive and linguistic maturation differentially shapes the outcomes of attentional processing at a local network level.

O objetivo deste trabalho foi avaliar a capacidade de sustentação de uma floresta nativa explorada, mediante o conhecimento da estrutura da floresta antes e após a exploração florestal, buscando recomendar medidas para minimizar os impactos causados pelas atividades de exploração sobre a vegetação adulta remanescente. Observou-se aumento no número de espécies e famílias dois anos após a exploração, em nível das adultas, ou seja, DAP > 5 cm, em razão do ingresso de espécies, o mesmo não sendo observado para classes menores que esta. O padrão de distribuição das espécies foi bastante afetado pela exploração, mas devido ao dinamismo da floresta ele deverá ser avaliado na época da próxima exploração. The objective of this study was to evaluate the sustainability capacity of a logging native forest based on the knowledge of its structure before and after logging, aiming to determine measures to minimize the impacts caused by harvesting on the remaining vegetation. It was observed an increase in the number of families and species two years after logging at the adult level, i.e., DBH > 5 cm, due to ingrowth, the same not being observed in the lowest level. The distribution pattern was affected by logging but due to the dynamism of the forest, it should be evaluated before the next logging.

This study aimed to explore the neural development status of the visual system of children (around 8 years old) using contrast sensitivity. We achieved this by eliminating the influence of higher order aberrations (HOAs) with adaptive optics correction. We measured HOAs, modulation transfer functions (MTFs) and contrast sensitivity functions (CSFs) of six children and five adults with both corrected and uncorrected HOAs. We found that when HOAs were corrected, children and adults both showed improvements in MTF and CSF. However, the CSF of children was still lower than the adult level, indicating the difference in contrast sensitivity between groups cannot be explained by differences in optical factors. Further study showed that the difference between the groups also could not be explained by differences in non-visual factors. With these results we concluded that the neural systems underlying vision in children of around 8 years old are still immature in contrast sensitivity.

The purpose of this study was to clarify characteristics of age-related changes in body shape in adolescence, in 11- to 19-year-old boys and girls, by using previously reported physique models of adult men and women as the scale. The scale consisted of four factors obtained by factor analysis using 30 items as variables, such as the values measured for the physique, skinfold thickness and body composition. The four factors were Factor 1: body fat, Factor 2: mass, Factor 3: Ieg length to height ratio, and Factor 4: Iength, and were interpreted in the men and women in a similar manner. The subjects were 307 boys and 368 girls; all were healthy. Thirty items were measured and included the values measured for the physique, skinfold thickness and body composition, as in the men and women. Factor scores in the subjects were standardized by mean and standard deviation for each item in the adult subjects, and calculated for individuals by using the coefficient of factor score in the adult subjects. The body shapes of the boys and girls were investigated from the factor score by age calculated for each factor. The following results were obtained: 1. Factor 1 tended to gradually decrease and reached the adult level at 15 years of age in the boys. But it tended to gradually increase and reached the adult level at 15 years of age in the girls; 2. Factor 2 rapidly increased with age in the first half of the teen years in the boys and girls, and it reached the adult level at 18 years of age in the girls, whereas this factor did not reach the adult level even at 19 years of age in the boys; 3. with regard to Factor 3, Ieg length tended to be temporarily somewhat long at 13-15 years of age in the boys, whereas the girls showed changes at approximate-ly the level of the adult subjects; 4. Factor 4 rapidly increased with age in the first half of the teen years in the boys and girls, and reached approximately the adult level at 17 and 15 years of age in the boys and girls, respectively. These results suggest that, the physique in adolescence is almost equivalent to that of adults and that body shape is essentially fully formed in the early 20s in boys and by about 18 years in girls through rapid growth in both mass and length during the first half of the teen years., Applied human science : journal of physiological anthropology. 1995, 14(5), p.227-234

Objective: To determine the range and variation in costs and service characteristics between different levels of specialist neurorehabilitation services in England, and to determine key predictors of service costs. Design: A retrospective analysis of service costs, staffing and activity levels, with comparison across service types. Setting: Specialist neurorehabilitation services ( n = 17) from different areas of England, were divided into three types according to predefined criteria: adult level 1 (tertiary) ( n = 8) and level 2a (supra-district) ( n = 7) services; and children’s services ( n = 2). Main measures: Annual service costs were collated using a standard costing template, and divided according to principal cost type (direct/indirect/overheads) and behaviour (variable/non-variable). For comparison between the level 1 and 2a services, costs and service characteristics were calculated per occupied bed. Results: The percentage breakdown of costs was consistent across all three service types, with direct costs making up 83%, indirect 10%, and overheads 7% of total costs. The median variable component ranged from 75 to 76%. Staff pay made up 66% and accounted for 95% of the variance of the total costs in adult services. Level 1 services had higher total staffing costs, mainly reflecting higher therapy staff numbers ( z = –2.0, P = 0.05). The median total costs/bed-day were: level 1 £530 (interquartile range (IQR) 435–574) (equivalent to US$860 or €650) and level 2a £402 (US$650 or €459) (IQR 326–451) ( z = –2.5, P = 0.009). Children’s services cost almost twice that (£1017–1177). Conclusions: Expected variations in cost are largely due to differences in staff costs. Total staff costs projected by 150% provided a reasonable estimate of total unit costs.

Adolescence is a transitional stage of development characterized by protracted refinements in the neural circuits required for adult level proficiency of working memory. Because impaired working memory is a hallmark feature of several psychiatric disorders that have their onset during adolescence, model systems that can be used to assess the maturation of working memory function, and of disease-related risk factors that disrupt its development, are of particular importance. However, few studies have investigated the maturation of working memory in nonhuman primates. Thus in the present study, we adapted two working memory tests that are among the most widely used in human and adult nonhuman primates, for adolescent rhesus monkeys. Using a touch-screen apparatus, monkeys were trained on a spatial delayed-response task to assess spatial working memory and a delayed match-to-sample task to assess object working memory. The results indicate that adolescent rhesus monkeys readily and efficiently acquire the ability to perform touch-screen based, complex tests of working memory. These data establish that distinct components of adult prefrontal cortex-dependent cognitive functions can be effectively modeled and evaluated in adolescent monkeys. As such, this approach should be useful for assessing the influence of environmental risk factors on the protracted maturation of working memory in adolescent macaques.

Change blindness describes the surprising difficulty of detecting large changes in visual scenes when changes occur during a visual disruption. In order to study the developmental course of this phenomenon, a modified version of the flicker paradigm, based on Rensink, O’Regan & Clark (1997), was given to three groups of children aged 6–12 years and to a group of adults.This paradigm tested the ability to detect single colour, presence/absence and location changes of both high and low semantic importance in a complex scene. Semantically important changes were detected more quickly and accurately than less semantically important changes, by all age groups, indicating that children had the same attentional priorities as adults. Older children achieved more efficient and accurate detection of changes than younger children and reached almost adult level at 10–12 years old. Theseimprovements parallel age-related developments in attention and visual perception.

From measurements of metabolizable energy (ME) intake (doubly labeled water technique), prey capture rates, and time spent foraging, we calculated both foraging efficiency (FE) and rate of energy gained while foraging (t,) of adult Yellow-eyed Juncos (Junco phaeonotus) and their offspring throughout the breeding season. , (kJ ME acquired per hr spent foraging) of adult Yellow-eyed Juncos varied 1.7 fold over the breeding cycle, as adults adjusted both the amount of time they spent foraging and their FE to meet changing energy demands and time constraints. Males paired to incubating females, and males and females feeding fledglings acquired energy at substantially lower rates (ca. 15-17 kJ/hr) than incubating females (26 kJ/hr) or than males and females feeding nestlings (21 kJ/hr). From this, we infer that adult juncos may reduce their FE when energy demands and/or time constraints are relaxed, either because the costs of inefficient foraging are negligible during these periods or because there are hidden costs or risks associated with foraging more efficiently. f of juvenile juncos increased 2.1 fold from a low of 5.3 kJ/hr during their first week of parental independence (a period of marked juvenile mortality due to starvation) to 10.9 kJ/hr (about 75% of the lowest adult level) by six-weeks post-independence. Juvenile FE increased linearly with age as the young gained proficiency at foraging. By extrapolation, juvenile FE would not have reached adult levels until the young were about four months old.

Deze studie vergelijkt de reclamewijsheid van kinderen en volwassenen. Door middel van een computergestuurde vragenlijst is nagegaan op welke leeftijd kinderen een volwassen niveau van reclameherkenning en begrip van de verkoop- en persuasieve intentie van reclame bereiken.This study examines the specific age at which children reach adult levels of cognitive advertising competences. In a computer-assisted survey of 296 children (8-12 years) and 198 adults (18-30 years), we investigated at what age children reach adult levels of (a) advertising recognition, and (b) understanding of advertising's selling and persuasive intent. Our findings showed that around the age of 10-11, most children have reached an adult level of advertising recognition. However, at age 12, children have still not acquired an adult-like understanding of advertising's selling and persuasive intent. Finally, children's understanding of the selling intent of advertising develops before their understanding of its persuasive intent.

Com o propósito de avaliar o efeito da refrigeração sobre o exame hemogasométrico, foram utilizados 12 ovinos machos, hígidos, da raça Santa Inês, com cerca de quatro meses de idade e peso variando entre 30 e 45 kg. As amostras de sangue destinadas ao exame hemogasométrico foram coletadas em duplicata utilizando-se agulhas descartáveis acopladas à seringas plásticas contendo cerca de 1000UI de heparina sódica. Durante e após a coleta tomou-se o cuidado de evitar a entrada de bolhas de ar no interior da seringa. As amostras não conservadas foram mantidas a temperatura ambiente, entre 23 e 25°C, e aquelas destinadas à refrigeração foram acondicionadas em isopor contendo 3kg de água gelada e 3kg de gelo, mantendo-se assim uma temperatura entre 0 e 4º C. As análises hemogasométricas foram determinadas imediatamente após coleta e com 1,2,3,4,5,6,8,10,12 e 24 horas. As análises dos resultados indicaram alterações significativas nas amostras mantidas a temperatura ambiente, caracterizado-se por diminuições, a partir da 4, 8 e 10 horas após coleta, para os valores do pH, BE e StB, respectivamente, e por aumento, a partir da 6 hora, para os valores da PCO2. Com relação as amostras conservadas, não foram evidenciadas variações significativas dos parâmetros ao longo dos tempos de análise. Conclui-se, portanto, que amostras de sangue venoso de ovinos são viáveis, para a realização do exame hemogasométrico, até 24 horas após coleta, desde que mantidas sob adequada refrigeração.

Concern about the topic of civic engagement has centered on the increasing reduction of voter turnout and the apparent alienation and “disconnect” of the general population with the process of government. This study, undertaken at the request of the leaders of a small town in southern New Hampshire is a two-step research plan (one quantitative, one qualitative). Results of both the survey portion of the research and the focus groups reveal an electorate (both adult and youth) which is concerned and informed, but mildly alienated and which register mild levels of efficacy. Suggestions made to try and build unity and an overall spirit of cooperation not just on the adult level but for the youth population as well, include the use of study circles increasing town wide involvement and opening a dialog among those who most acutely feel this disconnect.

We used a visual evoked-potential measure to study the development of two components of pattern vision, vernier acuity and grating acuity, in humans from early infancy through adolescence. These two visual functions develop at similar rates and have nearly the same absolute values between 1 month and 6 years of age. After age 6, grating acuity is constant at the adult level, but vernier acuity continues to improve, becoming a hyperacuity. Vernier acuity reaches asymptotic levels around age 14 years. These results suggest that adultlike vernier hyperacuity is not limited by spatial resolution or sensitivity of small receptive fields, but rather that the limitation is imposed by higher-level processing. Sensitivity, connections in visual cortical areas, or both therefore retain plasticity throughout childhood and into adolescence.

In recent years, the use of CT has increased rapidly both in adults and children. This development is of special concern for the paediatric radiologist, since ionising radiation carries a higher risk in children compared with adults. This is due to higher tissue radio-sensitivity and longer life expectancy. Therefore, the development of age-adjusted or weightadjusted CT protocols in children is of major importance. Dose reduction, by obtaining the lowest acceptable (appropriate) image quality for answering the clinical questions, has to be the central goal of such efforts. Several articles have been published in recent years giving recommendations on dose-reduction techniques in paediatric CT, but only sparse information is available regarding the resulting image quality. Furthermore, there is no definition of what constitutes appropriate image quality in paediatric CT, in particular with regard to age, body region and clinical setting. CT protocols for children were primarily based on empirical data from adult protocols; in many cases, only tube current (mAs) was reduced, while either keeping the voltage (kVp) at adult level or reducing it without knowledge of the resulting image quality, in particular low-contrast detectability. It is well known that CT image quality can be evaluated by mathematically measurable quality indices such as quantum noise, signal-to-noise ratio, contrast-to-noise ratio, dose efficiency and so on. Even at the beginning of CT application in children in the late 1970s, it was well known that the greatest challenge in paediatric CT is to cope with low contrast and lack of fat, in particular in infants and young children. But, even today, very limited data are available on what is an appropriate low-contrast detectability. Our vision was to optimise paediatric CT technique, in particular radiation dose and image quality, based on a systematic scientific approach using semi-anthropomorphic phantoms for different age groups. The idea was to challenge the “top-down” approach (empirical extrapolation of adult protocols) by developing a reproducible and widely applicable standard via a “bottom-up” approach. For this purpose, phantoms were developed and a project was started.

Aims: The aim of the following study is to establish the incidence contributing factors and impact of the missed injuries in pediatric trauma patients at adult trauma center on the prognosis and overall outcome of these children. Settings and Design: Longitudinal prospective cohort study involving 603 patients in over 06 months. Materials and Methods: The relevant data (as defined) of all included patients were recorded. These patients were then followed to document the total length of hospital stay and the injury list defined at the discharge or on the 7 th day of admission; whichever came first. The injury severity score (ISS) at admission was compared with final ISS (multivariate regression analysis). Results: Total 115 (19.1%) missed injuries (adult + pediatric both) were discovered, out of which 71 (61.7%) were pediatric trauma missed injuries. The pediatric trauma missed injuries were 32.2% of all pediatric trauma patients and 11.8% of all trauma patients. Main contributing factors were incomplete assessment (52.5%) and patients′ arrival time. None of the missed injuries led to any mortality, morbidity or increased length of hospitalization. Final ISS did not correlate with missed injury. Conclusions: Missed injuries are a significant problem in trauma patients especially the pediatric trauma patients. Though the majority of children with trauma were treated efficiently in the anaplastic thyroid carcinoma, but there is a need for improvement in patient assessment and monitoring, that is, extended tertiary survey; with special exposure to the attending residents at casualty about pediatric trauma and its pathophysiology.

Modifications at V-(D)-J junctions increase the diversity of T-cell receptors (TCR). It has been shown that the levels of N-nucleotide insertion at the V-(D)-J junction in TCR transcripts are different between fetal and adult stages. To clarify developmental stages and pathways of gamma delta T cells in the liver, we analysed the nucleotide sequence of V gamma 1.1-J gamma 4 junctions of intra-hepatic lymphocytes (IHL), spleen cells and developing thymocytes from normal and athymic nude mice. The level of N-insertion increased in thymocytes during ontogeny. The percentage of V gamma 1.1-J gamma 4 transcripts with N-insertion was 3% at day 16 of gestation, 42% at newborn, and 89% at 7 weeks. Transcripts from normal IHL showed intermediate levels of N-insertion between those of newborn and adult thymocytes. In contrast the percentage of N-insertion in nude IHL was 47%, and this value was comparable to that of newborn thymocytes. Among the transcripts of normal IHL, the sequences common with nude IHL showed a newborn level of N-insertion (38%), and the remaining sequences showed an adult level (89%). These results suggested the possibility that V gamma 1.1-expressing T cells in IHL might be a heterogeneous population consisting of the cells developed extrathymically as well as the cells developed intrathymically. The V gamma 1.1-J gamma 4 junctions from spleen cells showed less variability than those from IHL and adult thymocytes. It suggested that gamma delta T cells bearing specific V gamma 1.1 TCR develop and/or home in the spleen.

The postnatal development of Peyer's patches was investigated using routine histological and immunohistochemical techniques, focusing especially on the formation and increase in number of lymphoid follicles. In addition, we studied the influence on the development of lymphoid follicles in Peyer's patches of a sublethal dose of whole-body X-irradiation at an earlier postnatal age. At 1 day after birth, surface-IgM (sIgM)-bearing cells (B lymphocytes) were scattered throughout the Peyer's patch. At Day 3, sIgM-bearing cells had accumulated to form primary follicles in association with domed elevations. OX2-positive reticular cells (FDC) were detected in the centers of primary follicles at Day 5. The first appearance of germinal centers within lymphoid follicles was noted at 18 days, and at 21 days almost every follicle contained a germinal center. At Day 5, each Peyer's patch contained 6-8 lymphoid follicles, with the lymphoid follicles subsequently increasing in size and number. The mean number of follicles per Peyer's patch became 11.1, the adult level, at 21 days, and remained at this level for the next 15 weeks, even though respective follicles continued to enlarge during the observation period.Three-week-old rats received 400rad whole-body X-irradiation. At 3 and 7 days after treatment, lymphocytes were largely depleted from Peyer's patches, leaving behind the structural framework of the lymphoid follicles, interfollicular zones and domes. Stromal cells in the follicle remnants retained a positive reaction to OX2. By 14 days after X-irradiation, lymphoid follicles together with their germinal centers had begun to repopulate, and the number of restored lymphoid follicles per Peyer's patch was comparable to that in non-irradiated 3-week-old rats.In conclusion, the present results show that the majority of lymphoid follicles and their stromata are well established in Peyer's patches during the first 3 weeks after birth and are maintained for weeks and even months.

Purpose: Serum alkaline phosphatase (sALP) levels show great variation with age and sex in children and adolescents. We aimed to study pediatric ageand sex-specific reference ranges for sALP and how the pattern changed according to age . Methods: Cross-sectional results from 1366 healthy Korean children and adolescents (10-19.9 years) from the Korean National Health and Nutrition Examination Survey were analyzed. We constructed ageand sex-specific reference data for sALP with a Hitachi Automatic Analyzer 7600 using Pureauto S ALP. We assessed its peak both in relation to age. Results: Reference values for sALP according to age were constructed. Peak sALP levels were found at 12-13 years in boys (P < 0.001). Total sALP levels decreased to the adult level at the age of 17 in boys and 15 in girls, respectively. Conclusion: This study provides reference values for sALP by age for Korean children and adolescents. This normative data that includes upper and lower limits will provide a basis from which to better evaluate sALP levels, especially for bone disorders such as rickets and vitamin D deficiency. However, caution should be made in interpreting sALP levels because different buffers might lead to different values in the same serum.

This study was performed to identify the chronological changes of the knee angle or the tibiofemoral angles in normal healthy Korean children. Full-length anteroposterior view standing radiographs of 818 limbs of 452 Korean children were analyzed. The overall patterns of the chronological changes in the knee angle were similar to those described previously in western or Asian children, but the knee angle development was delayed, i.e., genu varum before 1 yr, neutral at 1.5 yr, increasing genu valgum with maximum a value of 7.8 degrees at 4 yr, followed by a gradual decrease to approximately 5-6 degrees of genu valgum of the adult level at 7 to 8 yr of age. These normative data on chronological changes of knee angles should be taken into consideration when evaluating lower limb alignment in children.

All terrestrial mammals studied so far do maximal amounts of sleeping at birth, with sleep time gradually decreasing to adult levels. This has led to the concept that sleep, with its characteristic immobility and unresponsiveness, is necessary for brain and body development. We reported1 that dolphins and killer whales have a very unusual developmental pattern: neonates are maximally and continuously active at birth, and this activity diminishes over a period of months to the adult level; in the postpartum period, mothers also abruptly cease the characteristic ‘hanging’ that constitutes the typical sleep behaviour in bottlenose dolphins and killer whales2,3,4,5. We did not claim that all sleep was abolished in the postpartum period. Rather, we reported that immobility was absent and that typical sleep posture increases with age, a pattern opposite to that seen in all land mammals studied so far. Sekiguchi . 6 and Gnone . 7 challenge our conclusions.

The effect of nicotinic acid on the changes of rat brain cerebroside levels has been studied during brain development. There is a gradual increase in the concentration of cerebroside from 12 days of age to adult level at approximately 47 days of age. However, the concentration of cerebroside was significantly lower in brain of rat fed the nicotinic acid-deficient diet. Therefore, nicotinic acid may play an important role in cerebroside synthesis in brain of developing rat.

1. The number of muscle fibres innervated by individual motor neurones (motor unit size) was measured in lumbrical muscles of rats aged 0--28 days, during the period of elimination of polyneuronal innervation. Motor unit sizes were determined from twitch tension measurements combined with muscle fibre counts made from histological sections of the muscles. 2. The relative tensions contributed by individual motor units declined from about 25% of the total tension at birth, to about 9% at 28 days of age. Intracellular recordings showed that part of this decrease reflected the elimination of synapses from polyneuronally innervated muscle fibres. 3. During the same period, however, new muscle fibres were produced. The total number of muscle fibres present increased from about 500 at birth to about 950 fibres in mature muscles. 4. These two processes were offsetting: some synapses were eliminated (from polyneuronally innervated fibres) while simultaneously others were formed de novo (on newly produced muscle fibres). Quantitative measurements showed that for the first 10 days after birth, there was little change in motor unit size. Thereafter production of new muscle fibres ceased, and motor unit size decreased to the adult level. 5. It is concluded that during early post-natal development, a lumbrical motor neurone maintains a nearly constant number of synapses, but extensively reorganizes its synaptic field, retracting synapses from some muscle fibres, while forming new synapses with other fibres.

The estrous cycle of Baiomys taylori averages 4.9 days. The gesta-tion period is estimated to be 22 to 23 days. A postpartum estrus is frequent. Puberty occurs as early as 28 days of age. Seven of 10 females between 25 and 29 days of age conceived within a week after pairing. The average weight of 47 individuals at birth was 1.20 ± 0.08 (SD) grams. The adult level of body temperature could be maintained at ages between 10 and 15 or 15 and 20 days for neonates exposed to 30 and 28°C, respectively, for a period of 2 hours. Growth during the first 20 to 35 days occurred in two phases with the first phase exhibiting an instantaneous growth rate of 7.50 ± 0.32 and 7.29 ± 0.42 per cent of body weight per day for experimentals (those young used for metabolic as well as body temperature and body weight measurements) and controls (those young used only for body weight measurements), respectively. The second growth phase commenced at 11.3 days for the experimentals and 17.0 days for the controls. The second growth phase averaged only. 4.01 ± 0.26 and 3.30 °: 0.52 per cent of body weight per day for the experimentals and controls, respectively, and coincided with the full development of homeothermy. At a body temperature of 36 to 37°C and a body weight of 2.0 to 2.5 grams—the lower size limit for homeothermy—the oxygen consumption was 3.6 ° 0.40 (2 SE) cc O2/g/hr if the ambient temperature was 30°C. The oxygen consumption for neonates averaging 22.5 ± 0.7 days of age was 4.31 ± 0.16 cc O2/g/hr at an ambient temperature of 30°C. This relatively high level of oxygen consumption indicated that 30°C was below thermal neutrality, the ambient temperatures at which the oxygen consumption of adults is 1.95 ± 0.25 (2 SE).

Lung infections are a common cause of morbidity and mortality in neonates. To evaluate neonatal lung defenses against pneumococci, we challenged rats with aerosols of encapsulated pneumococci in an airborne infection apparatus. Whereas adult rats cleared greater than 95% of inhaled type 1 or type 25 pneumococci within 4 h, pneumococci proliferated in the lungs of newborn rats and reached 200-600% of the baseline value by 4 h and 1000-1700% by 24 h. As neonatal rats matured, their ability to clear inhaled pneumococci improved, but compared with adults some impairment in clearance was present until approximately 4 wk of age. Newborn rats had significantly fewer resident alveolar macrophages per g of lung tissue than did adults (p less than 0.001). Although the number of resident macrophages increased with time, a significant deficit in alveolar macrophages persisted for the first 3 wk of life (p less than 0.01). Aerosols of pneumococci caused an influx of granulocytes into the lungs of adult rats within 4 h, compared with 24 h for neonatal rats. Even at 24 h after pneumococcal challenge, newborn rats had significantly fewer granulocytes per g of lung tissue (p less than 0.05) than did adults, although 7-day-old rats had reached an adult level by this time. Significant (p less than 0.05) increases in granulocyte chemotactic activity were observed in lavage fluids of adult, but not newborn, rats after pneumococcal challenge. Thus, impaired clearance of pneumococcal aerosols by neonatal rats was associated with an age-dependent deficiency in numbers of resident alveolar macrophages and impaired generation of chemotactic activity and recruitment of granulocytes to the lung.

Twenty boys at each age level 7, 10, and 13 years and 20 adult males were tested for choice manual reaction times to photographs of faces or letter pairs tachistoscopically presented 3 1/2 degree to the left or 3 1/2 degree to the right of a central fixation point, in the left visual field (LVF) or the right visual field (RVF) respectively. All subjects were right-handed. Subjects were tested monocularly. They used a different hand and a different eye in the first and second half of trials. Eye order and hand order were randomized across subjects. Seven- and 10-year-olds were intermittently rewarded with a poker chip following fast correct responses. Analysis of correct reaction time scores indicated an overall LVF superiority for the speed of response to faces, but no significant field differences for responses to letter pairs. The interaction of these field-stimulus effects with age was not significant, suggesting that the obtained field effects with faces and letter pairs were consistent across the range of ages tested. The results of comparisons of field differences within individual subjects suggested a "switchover" from a left-field advantage with letter pairs at age 7 to a right-field advantage at the adult level; this tendency, however, was not significant. None of these results was influenced by the use of different hands or eyes or to frequencies of commission of errors. The results suggested that a left-field advantage in speed of response to familiarized faces is found as early as 7 years of age and does not change appreciably thereafter. The finding of a significant left-field advantage for faces in the 7-year-old group represented an earlier age of left-field, right hemisphere lateralization for face stimuli than that previously obtained by other investigators. The failure to find over field differences with letter pairs was attributed to a possible tendency among subjects to process to letters visually (i.e., graphemically), a tendency which may have been more marked in the 7-year-old group due to the relative inexperience of children of this age with alphabetical material.

As an extension of previous studies, we reexamined the developmental change in trophic activity of chicken serum on chicken myogenic cells in vitro and attempted to elucidate it on the basis of possible changes in serum transferrin (Tf), the myotrophic activity of which depends both on its concentration and on the level of its iron-saturation. The myotrophic activity was found to be low until the second week in ovo, then to increase rather abruptly to a plateau at about the time of hatching, and then to decrease to the adult level. Determination of the concentration and level of iron-saturation of serum Tf suggested that the change in myotrophic activity was mainly caused by these two parameters, though another factor(s) may also be involved.

The development of monoclonal antibodies to cell-surface antigens has provided method for characterizing distinct subpopulations of T-cells. In the present study we have quantified peripheral blood T-cell subpopulations in premature infants born weighing less than 1,500 g (1123 +/- 223 g) and ranging in gestational age from 25 to 32 weeks. The relative proportion of T4 cells in the very low birth weight (VLBW) infants was markedly higher at 1 week and 1 month of age (mean +/- SEM; 67.5 +/- 4.1 and 59.2 +/- 1.6) than in adult controls (47.2 +/- 1.5). The percentage of T4 cells remained elevated until 6 months of age, when it decreased to a level comparable to that in adults. In contrast, the proportion of T8 cells was significantly lower than the adult level at 1 week and 1 month of age. The T4/T8 ratio in the VLBW infants was higher at 1 week (4.3 +/- 0.5) and 1 month (3.5 +/- 0.2) than in adult controls (2.0 +/- 0.1). Thereafter, the T4/T8 ratio decreased but was still significantly higher than that in adult controls at 6 months of age (2.6 +/- 0.2). The absolute numbers of total T-cells (T3) and T8 and T4 cells were significantly higher in VLBW infants. The numbers of T8 cells were significantly lower in the first month of life than at 3-6 months of age. These alterations in the T-cell subsets in the first 6 months of life suggest that postnatal T-cell phenotypic changes in VLBW infants may parallel the T-cell ontogenetic process which occurs during the last trimester of pregnancy in full-term infants.

A sensitive solid phase radioimmunoassay method was established for the specific quantitative determination of secretory IgA (sIgA) by taking advantage of the dual antigenicities of sIgA, one specific for α-chain and the other for secretory component (SC). The sIgA and IgA in the sample were first bound by anti-IgA antibodies coated on the polystyrene tube, then the amount of bound sIgA was quantified by the use of 125I-labeled anti-SC antibodies. This method is quite sensitive and allows us to distinguish sIgA from IgA and free SC which usually coexist in exocrine secretions. Linear relationship was observed between the bound radioactivity of radioiodinated anti-SC and the amount of sIgA in the range of 5 to 60 ng of sIgA. With this method, the urinary sIgA levels in normal children and adults were measured. Urinary sIgA was detected in half of infants within 7 days after birth, while it could be demonstrated in almost all of the infants by 14th day. Then, it gradually increased and reached about a half of the adult level by the age of puberty. This method will be useful for the sensitive and specific measurement of sIgA in various exocrine secretions.

The first appearance of spermatogenic cell types related to the age of the animal was studied in sections and tubular whole mounts of testes of normal mice (Cpb-N strain) up to 34 days pp. The first intermediate spermatogonia and leptotene spermatocytes were seen at days 4 and 7 p.p., respectively. It was found that the subsequent types of spermatogenic cells appear earlier than could be expected if spermatogenesis was to proceed at adult speed. [3H]thymidine labelling studies revealed that within a given interval of time, spermatocytes and spermatids in immature mice develop into more advanced cell types than in adults. The labelling studies and the observation that the cellular associations are always identical to those in the adult, indicate that the rate of acceleration in young mice is the same for spermatogonia, spermatocytes and spermatids. The mean duration of the cycle of the seminiferous epithelium during the age interval of 10 to 30 days p.p. is 7.51 +/- 0.10 days, compared to 8.61 +/- 0.08 in the adult. It increases gradually towards the adult level, reaching the value of 8.45 +/- 0.17 days between days 33 and 56 p.p.

Changes in hematological values were studied with 131 healthy cynomolgus monkeys aged less than 11 months. The parameters measured were erythrocyte count (RBC), hematocrit value (Ht), mean corpuscular volume (MCV), hemoglobin concentration (Hb), total leucocyte count (WBC), and differential leucocyte count. No remarkable change was found with RBC during the whole period of this study. Relatively high values were obtained with Ht, MCV, and Hb in the newborns aged 0 to 7 days. These values continued to decrease until 3 months of age, after which the values increased again attaining approximately adult levels at 11 months of age. WBC was very high at birth and then decreased to the minimum level at 3 days of age. It was followed by gradual increase until about 4 months of age at which a nearly adult level was attained. Lymphocyte counts were smaller than neutrophil counts on the day of birth. However, this numerical relation was inverted 2 days after birth and the lymphocyte counts became markedly larger than the neutrophil counts about 1 week after birth. Additionally, the values obtained from the cord blood of 6 Cesarean-delivered newborns were compared with those from the blood taken 5 hours after cesarean delivery.

The present study was planned on the basis of the exprimental results of the comparison of similarity of figures which change indirection and arrangement of elements in the previous paper (4, 5, 6, 7, 8, 9 10, 11). The purpose of the present study is an inquiry into the development of figure-recognition by proving the results of the comparison of similarity of figures through the analysis of the developmental curve of exact perception in the experimental situation of figure-identification and also of errors made in it.Two sets of figures used in the present experiment consits of the correct figure added to the figures used in the previous experiments (6, 9). Each set consists of a standard figure and seven elective figures. In the choice method, the subject was asked to select out of the latter the one which is the same as the former. In the recognition method, the former was first presented to the subject for ten second, and after its removal the latter was then presented. The subject was asked to select from the latter the one which is the same as the former. The number of subjects ranging in age from 3-4 to 13-14 years was 1276.The results were as follows:(1) In the developmental curve of exact perception in experimental situation of figure-identification, the critical period shifting to the adult level was found at about 8-9 years, and nearly 100% exactness was achieved at about 13-14 years. These ages coincide with those of operational level at the first and third stages in comparison of similarity of figures.(2) By analyzing the errors, we found whole-framework perception done in groups of children, 5-6 and 4-5 years of age, whereas simple-framework-perception done in a group of 3-4 year-old children. We can then say that children step from simple-framework-perception into whole-framework-perception of figures around the period of 4-5 years.

The experiment aimed to determine the second-order personality factor structure, in Q-data, as reliably at the child level as has been done at the adult level, and simultaneously to check on cross-cultural constancy. The HSPQ was administered to 209 12‐14 year‐old boys and girls in Australia and 296 in the U.S.A., and the 14 scales were intercorrelated and factored separately in each sample. Tests of factor number yielded five factors. Independent rotation to simple structure yielded four factors easily matched across cultures; these are the same as have been recognized in adults: exvia-invia, anxiety-adjustment, cortertia-pathemia, and independence. The practical utility of the result lies in providing weights to get scores from the HSPQ on second order factors such as anxiety and exvia. Among the theoretical outcomes are: (1) the evidence of cross-cultural constancy; (2) the finding that variance from anxiety in children, unlike adults, exceeds that due to exvia; and (3) the demonstration that ...

Most people who have aphasia are bewildered by their loss of power to express themselves through language and its many related skills. The person with aphasia may have difficulty not only in speaking or understanding the speech of others, but also in remembering what has been said, recognizing and using familiar objects, reading with comprehension, writing to communicate on an adult level, or coping with such numerical relationships as those of time, money, or calculation. Aphasia is most commonly seen in persons who have had a cerebral vascular accident, but may also be seen in persons with cerebral trauma. Word-finding difficulty (inability to recall a specific word) is one of the most frequent aphasic impairments. We all have this difficulty occasionally. Have you ever been out with a friend when you see someone else you know? You stop to chat and when you introduce your friends to each other, you draw a blank. You forget the name of one of your friends. Or, have you ever been talking and suddenly you are unable to find a word needed .to express your ideas? For us, this "forgetfulness" is an infrequent occurrence, but for the person with aphasia these word-finding difficulties are common. He wants to tell us something, but is unable to recall the word or the group of words he needs in order to convey his

The ratio of alpha to beta cells examined in rats and bats is at a high level in the young of each of these Apecies. It falls to lower values at about puberty because of an active mitotic multiplication of beta cells. After the adult level of the alpha/beta cell ratio has been reached in bats, carp and tench, it is not affected by changes in the body state arising from hibernation.

It has been found that children under eleven years of age attach little meaning to conventional names of time periods, especially dates.1 Their growth in the knowledge of conventional time is a slow process starting at the age of four and arriving at adult level after the age of thirteen. Children appear to learn first the meaning of time words in ordinary use, such as the day or the week. Passing from these to an understanding of chronology and the arrangement of historical periods is a difficult mat ter. Not until the pupils are eight years old are they able to distinguish the past from the present. For years after they find it difficult to under stand dates. Not until pupils are eleven years do they pay attention to subdivisions of the past, or period history.