Appropriate Levels Of Activity Research Articles

SY-Track: A tracking tool for measuring chicken flock activity level

Poultry farming plays a vital role in providing animal protein for human consumption. Implementing efficient automation in chicken farming while ensuring the welfare and health of the birds is crucial. Monitoring changes in chicken activity can reflect their welfare and overall health, and provide a basis for agricultural production systems. Thus, maintaining appropriate levels of activity is vital for successful poultry farming. This paper proposes a method for detecting the activity levels of chicken flocks based on object detection and tracking. Firstly, a dataset for chicken flock detection and tracking was established. Secondly, an improved algorithm named SY-Track was proposed, leveraging optimized YOLOv7-tiny and improved StrongSort to ensure accurate chicken flock detection, tracking, and calculation of activity indices. In the optimized YOLOv7-tiny algorithm, a new lightweight convolution named Spatial Separable and Ghost Convolution (SAGConv) was proposed, complemented by the incorporation of the Efficient Long-range Spatial Aggregation Network (ELAN-SA). SAGConv effectively reduced both model parameters and computational complexity. The proposed ELAN-SA significantly improved the performance of YOLOv7-tiny. Additionally, the adoption of SIOU improved the convergence of bounding box regression. In the improved StrongSort algorithm, the optimized Kalman filter with predicted width and height was employed to enhance tracking performance. Compared to the original model, the improved YOLOv7-tiny reduced the model size by 48.75 %, increased the FPS by 44.15 %, decreased the computational load by 44.62 %, while achieving an AP50 of 96.30 %. The improved StrongSort algorithm achieved impressive MOTA values of 84.33 %, 79.00 %, and 71.62 % on three videos with different camera angles and flock disturbances. Finally, the SY-Track algorithm was utilized for calculating the Unrest Index to reflect activity level of chicken flock. The lightweighting SY-Track algorithm demonstrates superior competitiveness compared to mainstream detection and tracking algorithms when applied to the chicken flock dataset. It effectively calculates the Unrest Index of the chicken flock, providing a foundation for intelligent agricultural production and automation in chicken farming worldwide.

Effects of hippotherapy on gross motor function in children and adolescents with cerebral palsy – a scoping review

Introduction: Cerebral palsy is one of the most commonly diagnosed neurological syndromes in children today. The most prevalent abnormalities in the development of patients with cerebral palsy are related to general motor skills, body posture and muscle tension. The sum of these disorders affects, inter alia, gross motor skills, which are movements involving either the entire body or a significant part of it. These include, for example, walking, running, jumping, swimming, and cycling. Nowadays, medicine offers many types of therapy to patients with cerebral palsy. Properly adjusted, they provide a chance to maintain appropriate levels of activity and physical fitness, and prevent the patient’s clinical condition from worsening. One of the supportive forms of therapy for people suffering from cerebral palsy is hippotherapy, which, thanks to its universal status, is an important complement to the rehabilitation process. The aim of the study was to assess the effects of hippotherapy on gross motor skills in children with cerebral palsy based on a literature review. Materials and methods: The MEDLINE PubMed medical database was reviewed as recommended by PRISMA, using the following keywords: “cerebral palsy” in combination with “hippotherapy” and “gross motor function.” The review included clinical trials examining the effects of hippotherapy on gross motor skills in children with cerebral palsy. Results: A total of 25 articles published between 1998 and 2021 were identified. The effects of hippotherapy on changes in gross motor activity were assessed using the Gross Motor Function Measure (GMFM), Functional Status Scale, Pediatric Balance Scale, Bruininks–Oseretsky Test of Motor Proficiency. Second Edition (BOT-2) scales, Gross Motor Function Classification System (GMFCS), and changes in selected gait determinants including walking speed and stride length. Conclusions: Hippotherapy improves gross motor skills in children and adolescents with cerebral palsy aged 3–19, classified as GMFCS levels I–V. However, more research is needed to establish the long-term effects of hippotherapy.

Isolation Related to the COVID-19 Pandemic in People Suffering from Parkinson's Disease and Activity, Self-Assessment of Physical Fitness and the Level of Affective Disorders.

Background: Staying at home for long periods and limiting various types of activities and social contacts due to the COVID-19 pandemic may have negative consequences for health. This is especially true for people suffering from chronic diseases, in whom an appropriate level of activity and social contacts delay the progress of the disease. This group includes people diagnosed with Parkinson’s disease—PD. Aim: It was decided to investigate the effect of COVID-19 isolation related to self-assessment of physical fitness, physical activity, and the level of anxiety and depression in people with PD. Methods: The study included 30 patients diagnosed with Parkinson’s disease. We compared the results of the pre-pandemic questionnaire and the telephone interview with the same questions—after the period of isolation due to COVID-19. The questionnaire included questions about physical activity and fitness self-assessment. The level of affective disorders was tested using HADS. Results: There was a statistically significant decrease in the physical activity of the respondents after isolation related to COVID-19 (p < 0.05). Self-assessment of physical fitness also decreased, but the differences were not statistically significant. In the post-isolation study, only 50% of the respondents had normative values for anxiety and only 40% for depression. The analysis showed that the level of physical activity—the independent variable, explains anxiety in 30% and depression in 27%. Conclusions: Pandemic isolation has significantly reduced physical activity in PD patients. There was a certain drop in the self-esteem of physical fitness in these people. Physical fitness is an important predictor of preventing the affective disorders of anxiety and depression. The effects of isolation due to COVID-19 require further research.

Abnormal Lower Extremity Movements in a Term Infant.

Abnormal Lower Extremity Movements in a Term Infant.

A Domestication-Associated Gene GmPRR3b Regulates the Circadian Clock and Flowering Time in Soybean

Improved soybean cultivars have been adapted to grow at a wide range of latitudes, enabling expansion of cultivation worldwide. However, the genetic basis of this broad adaptation is still not clear. Here, we report the identification of GmPRR3b as a major flowering time regulatory gene that has been selected during domestication and genetic improvement for geographic expansion. Through a genome-wide association study of a diverse soybean landrace panel consisting of 279 accessions, we identified 16 candidate quantitative loci associated with flowering time and maturity time. The strongest signal resides in the known flowering gene E2, verifying the effectiveness of our approach. We detected strong signals associated with both flowering and maturity time in a genomic region containing GmPRR3b. Haplotype analysis revealed that GmPRR3bH6 is the major form of GmPRR3b that has been utilized during recent breeding of modern cultivars. mRNA profiling analysis showed that GmPRR3bH6 displays rhythmic and photoperiod-dependent expression and is preferentially induced under long-day conditions. Overexpression of GmPRR3bH6 increased main stem node number and yield, while knockout of GmPRR3bH6 using CRISPR/Cas9 technology delayed growth and the floral transition. GmPRR3bH6 appears to act as a transcriptional repressor of multiple predicted circadian clock genes, including GmCCA1a, which directly upregulates J/GmELF3a to modulate flowering time. The causal SNP (Chr12:5520945) likely endows GmPRR3bH6 a moderate but appropriate level of activity, leading to early flowering and vigorous growth traits preferentially selected during broad adaptation of landraces and improvement of cultivars.

Clinical Outcome after Anterior Cruciate Ligament Reconstruction Using Hamstring Tendon Autograft: A Prospective Study with 6 Months Follow-Up

Objective: The goal of our study is to show that after single-bundle anatomic ACL reconstruction technique using hamstring tendon autograft (quadrupled semitendinosus and gracillis tendons), there is excellent objective knee stability and the return of flexor muscles strength.Methods: 65 patients aged 13–46 entered our study and were operated with a single bundle ACL reconstruction technique using hamstring tendon autograft. The operation and postoperative protocol were standardized. Patients were evaluated at 3 and 6 months postoperatively with clinical examination, KT–1000 measurements, functional scores (Balance index, Hop index, IKDC, isokinetic testing) and subjective questionnaire (Lysholm score, Tegner score).Results: 65 patients were evaluated 3 and 6 months postoperatively. Lachman test was negative in 92% and the pivot-shift test was negative in 89% of patients at 6 months follow-up. KT–1000 stability testing revealed a difference of 1.05 mm ± 2.83. At final follow-up, overall IKDC evaluation grade A and B were obtained in 96% of patients. The mean Lysholm score, 6 months postoperative was 94. There was no statistically significant difference in the angle of peak torque inflexion at 60°/s at 6 months follow-up.Conclusion: Our study shows that the strength of knee flexion six months after harvesting both hamstring tendons returns. However, there is still a statistically significant difference in knee flexion peak torque, when comparing the operative and non-operative side. Single bundle anatomic ACL reconstruction gives excellent knee stability and good clinical results with normal knee range of motion and returns to the appropriate level of activity.

The DALICO Study

Introduction: Physical activity as a treatment is gravely under-used in health care. One problem is determining the appropriate level of activity for the individual patient; another is maintaining activity over time. We have chosen to introduce a computer-based questionnaire to give the health-care provider a better overview of the patient's health status, activity level and motivation to change. This information will enable the care-giver (physiotherapist, psychologist, physician, etc.) to tailor the intervention to his/her patients.

Targeted physiotherapy treatment for low back pain based on clinical risk can improve clinical and economic outcomes when compared with current best practice

Does a stratified primary care approach for patients with low back pain result in clinical and economic benefits when compared with current best practice? A randomised, controlled trial with stratification for three risk groups and a targeted treatment according to the risk profile. Group allocation was carried out by computer-generated block randomisation in a 2:1 ratio. Ten general practices in England. Men and women at least 18 years old with low back pain of any duration, with or without associated radiculopathy. Exclusion criteria were potentially serious disorders, serious illness or comorbidity, spinal surgery in the past 6 months, pregnancy, and receiving back treatments (except primary care). In the intervention group decisions about referral to risk group were made by use of the STarT Back Screening Tool. The 30-min assessment and initial treatment focused on promotion of appropriate levels of activity, including return to work, a pamphlet about local exercise venues and self-help groups, the Back Book, and a 15-min educational video Get Back Active. Low-risk patients were only given this clinic session. Medium-risk patients were referred for standardised physiotherapy to address symptoms and function. High-risk patients were referred for psychologically informed physiotherapy to address physical symptoms and function, and psychosocial obstacles to recovery. In the control group a 30-min physiotherapy assessment and initial treatment including advice and exercises was provided, with the option of onward referral to further physiotherapy, based on the physiotherapist's clinical judgement. The 12 months score of Roland and Morris Disability Questionnaire (RMDQ). Secondary measures were referral for further physiotherapy, back pain intensity, pain catastrophising, fear-avoidance beliefs, anxiety, depression, health-related quality of life, reduction of risk-subgroup, global change of pain, number of physiotherapy treatment sessions, adverse events, health-care resource use and costs over 12 months, number of days off work because of back pain, and satisfaction with care. Of 851 patients assigned to the intervention (n=568) and control groups (n=283) a total of 649 completed the 12 months follow-up. Adjusted mean changes in RMDQ scores were significantly higher in the intervention group than in the control group at 4 months (4.7 [SD 5.9] vs 3.0 [5.9], between-group difference 1.8 [95% CI 1.6 to 2.6]) and at 12 months (4.3 [6.4] vs 3.3 [6.2], 1.1 [0.6 to 1.9]). At 12 months, stratified care was associated with a mean increase in generic health benefit (0.039 additional QALYs) and cost savings (£240.01 vs £274.40) compared with the control group. There were significant differences in favour of the intervention group in many of the secondary outcomes. A stratified management approach including a prognostic screening and treatment targeting, showed improved clinical and economic benefits when compared with current best practice.

Determining Exercise Intensities of Gardening Tasks as a Physical Activity Using Metabolic Equivalents in Older Adults

The objective of this study was to determine the exercise intensities of 15 gardening tasks in older adults using a portable indirect calorimeter. Twenty older Korean adults (16 females, four males) older than 65 years of age (average 67.3 ± 2.7 years) were recruited from the community of Gwangjin-gu, Seoul, South Korea. The subjects visited a garden created for the study at Konkuk University, Seoul, South Korea, three times and performed a total 15 gardening tasks. Subjects wore a portable calorimetric monitoring system (Cosmed K4b2) with telemetry that allowed measurement of oxygen consumption as they conducted each gardening task over a 5-min period and during a subsequent 5-min rest period while seated on a chair between each task. Their heart rate was also continuously measured using radiotelemetry (Polar T 31) during the test. The gardening tasks performed were of low to moderate intensity physical activities [1.7–4.5 metabolic equivalents (METs)]. Tasks using both upper and lower body (e.g., digging, fertilizing, weeding, raking, tying plants to stakes) required moderate-intensity physical activity (3–4.5 METs); those using the upper body while standing or squatting (e.g., pruning, mixing soil, planting seedlings, sowing, watering using a watering can or hose, harvesting) were low-intensity physical activities (1.7–2.9 METs); and tasks requiring limited use of the upper body while standing (e.g., filling containers with soil, washing harvested produce) were the least demanding physical activities of the gardening tasks tested. The results will allow more precise tailoring of gardening activities of older individuals to achieve appropriate levels of activity for good health.

Mechanisms of GABAergic Homeostatic Plasticity

Homeostatic plasticity ensures that appropriate levels of activity are maintained through compensatory adjustments in synaptic strength and cellular excitability. For instance, excitatory glutamatergic synapses are strengthened following activity blockade and weakened following increases in spiking activity. This form of plasticity has been described in a wide array of networks at several different stages of development, but most work and reviews have focussed on the excitatory inputs of excitatory neurons. Here we review homeostatic plasticity of GABAergic neurons and their synaptic connections. We propose a simplistic model for homeostatic plasticity of GABAergic components of the circuitry (GABAergic synapses onto excitatory neurons, excitatory connections onto GABAergic neurons, cellular excitability of GABAergic neurons): following chronic activity blockade there is a weakening of GABAergic inhibition, and following chronic increases in network activity there is a strengthening of GABAergic inhibition. Previous work on GABAergic homeostatic plasticity supports certain aspects of the model, but it is clear that the model cannot fully account for some results which do not appear to fit any simplistic rule. We consider potential reasons for these discrepancies.

“Imaging of the Intervention” a new paradigm for our specialty

Interventional Radiology (IR) is a subspecialty of diagnostic Radiology. It has dramatically developed in the recent past and has became part of daily practice in most Health Care centres in Europe and worldwide. Because of its major role in various diseases, IR has gained wide acceptance and despite turf battles on some intervention, IR are in a central position to create, perform, determine the indication and the follow-up of mini-invasive image guided interventions. It is common sense that optimized results and appropriate levels of activity of Interventional Radiology relies on sound clinical judgement but also in a large part on the results of Imaging workup. Unfortunately, Interventional Radiologists today share the experience that imaging is not optimized in several aspects and that there is a need for better understanding of the principle, the indications, results and complications of Interventional procedures. First of all, there is not enough awareness of the indications for IR procedures among diagnostic radiologists. How many cases are not referred to IR for advice, despite obvious feasibility? How many pelvic MR patients are not referred for possible Uterine Fibroid Embolization? How many aortic imaging studies are not referred for possible EVAR/TEVAR? How many typical osteoporotic fractures? How many complex biliary stenoses ?…. These missed opportunities are patients who lose the potential benefit of undergoing minimally invasive intervention. In addition the field of IR does not develop appropriately. Secondly, when reading the report from our diagnostic radiology colleagues, we know that we often have to re-analyse/re-interpret the images for our own purpose, in order to answer our own specific IR related questions. Examples include: CTA workup for Abdominal Aortic Aneurysms reporting on the “length of the aneurysm” but not on the infra-renal neck; Lower limb CTA reporting on “calcified arteries” and “infiltration” of the Superficial Femoral Artery with no attempt to search for a tight stenosis that could be amenable for balloon dilatation; Liver imaging reporting on “2 metastasis in the left liver” or HCC workup before chemo-embolisation that do not search for extra hepatic feeding arteries. There are many other examples covering the whole field of IR with all types of imaging techniques. Such reports which do not consider IR factors do not prompt referring clinicians to propose Intervention Radiological procedures for their patients, thereby reducing the appropriate growth and appreciation of IR. If all this is true for pre operative imaging it is certainly equally important for follow- up imaging. How many reports will really help us when we see the patient in consultation after an intervention? How many of our diagnostic colleagues truly understand which complications needs to be ruled out. How many diagnostic radiologists specifically assess tumour response the way Interventional Radiologists require it according to international consensus and to the way a specific intervention was performed in a specific patient? Here again, we often need to re-analyse the images and use our own “diagnostic radiology hat” to ensure that optimum/ focused information is derived from the images. All these considerations demonstrate each day that there is a need for a specific effort of teaching and training of all radiologists toward a better understanding of imaging tailored to the need of IR. The concept of “Imaging of the Intervention” that we propose today is a way to address this problem in all its aspect. “Imaging of the Intervention” would concentrate on proposing tailored training opportunities on all its aspects including lectures, courses, focused review articles, books and virtual material. This effort would deserve dedicated time during pre a post graduate programs of all Radiologists in order to widespread this specific knowledge in all its aspects in our Radiological Community world wide. We believe that the Radiology community must identify this need and this new opportunity for both diagnostic and Interventional Radiologists: the demand on diagnostic imaging and the expertise will increase just as the number and quality of intervention will increase in parallel for the global benefit of our specialty. Both diagnostic and interventional communities are missing major opportunities each day due to this absence of specific knowledge. All of us need to push forward the agenda on the concept of “Imaging of the Intervention” and put it into practice not only in our daily clinical practice but also at the academic level in national and European scientific societies.

Bridging Scales: A Three-Dimensional Electromechanical Finite Element Model of Skeletal Muscle

This paper introduces a framework for skeletal muscles that couples outputs from a detailed biophysically based electrophysiological cell model to a three-dimensional continuum-based finite element model of muscle mechanics. Due to the unique manner in which a skeletal muscle is activated, specifically the fact that neighboring fibers are electrically isolated and can act independently of each other, a completely new and novel coupling framework has been created. Within this framework, the electrical activity within a fiber is modeled with a biophysically based cell model, which is itself an amalgamation of several existing cell models. From this amalgamated cell model, specific output parameters that describe the level of crossbridge activity are computed and stored within a lookup table. This lookup table is then used to map the appropriate level of activity to all fibers within the muscle. To link the level of activity to a three-dimensional finite flement model of a skeletal muscle, which is based on principles of continuum mechanics, an upscaling method is introduced to compensate for the fact that the finite element mesh does not attempt to separately represent each individual fiber. This upscaling method allows the stress equilibrium equations to be computed at each Gauss point based on different values of the cell model outputs in all the neighboring cells. Since adjacent fibers can operate independently, the cell model outputs used in the finite element solution of the finite elasticity equations are discontinuous. The behavior and performance of the entire coupling framework is carefully analyzed in some simple test cases analyzing the reduction of the discretization error with respect to a sequence of uniformly refined meshes and different activation patterns. The results show that the error-reduction factors obtained from the electromechanical framework using triquadratic Lagrange and tricubic Hermite basis functions in solving the Galerkin finite element stress equilibrium equations are very similar to those obtained from a mechanics-only continuum-based model. Following this, an example of this process applied to the lateral pterygoid muscle is presented. The proposed framework can be used, for example, to investigate the mechanical effects with respect to cellular changes or to analyze the effects of different neuromuscular activation patterns on the tissue response.

Calcium‐dependent inactivation of calcium channels in cochlear hair cells of the chicken

Voltage-gated calcium channels support both spontaneous and sound-evoked neurotransmitter release from ribbon synapses of cochlear hair cells. A variety of regulatory mechanisms must cooperate to ensure the appropriate level of activity in the restricted pool of synaptic calcium channels ( approximately 100) available to each synaptic ribbon. One potential feedback mechanism, calcium-dependent inactivation (CDI) of voltage-gated, L-type calcium channels, can be modulated by calmodulin-like calcium-binding proteins. CDI of voltage-gated calcium current was studied in hair cells of the chicken's basilar papilla (analogous to the mammalian cochlea) after blocking the predominant potassium conductances. For inactivating currents produced by 2.5 s steps to the peak of the current-voltage relation (1 mm EGTA internal calcium buffer), single exponential fits yielded an average decay time constant of 1.92 +/- 0.18 s (mean +/- s.e.m., n = 12) at 20-22 degrees C, while recovery occurred with a half-time of approximately 10 s. Inactivation produced no change in reversal potential, arguing that the observed relaxation did not result from alternative processes such as calcium accumulation or activation of residual potassium currents. Substitution of external calcium with barium greatly reduced inactivation, while inhibition of endoplasmic calcium pumps with t-benzohydroquinone (BHQ) or thapsigargin made inactivation occur faster and to a greater extent. Raising external calcium 10-fold (from 2 to 20 mm) increased peak current 3-fold, but did not alter the extent or time course of CDI. However, increasing levels of internal calcium buffer consistently reduced the rate and extent of inactivation. With 1 mm EGTA buffering and in 2 mm external calcium, the available pool of calcium channels was half-inactivated near the resting membrane potential (-50 mV). CDI may be further regulated by calmodulin-like calcium-binding proteins (CaBPs). mRNAs for several CaBPs are expressed in chicken cochlear tissue, and antibodies to CaBP4 label hair cells, but not supporting cells, equivalent to the pattern seen in mammalian cochlea. Thus, molecular mechanisms that underlie CDI appeared to be conserved across vertebrate species, may provide a means to adjust calcium channel open probability, and could serve to maintain the set-point for spontaneous release from the ribbon synapse.

A simple screening method for determining knowledge of the appropriate levels of activity and risk behaviour in young people with congenital cardiac conditions

To assess a novel method for assessing risk and providing advice about activity to children and young people with congenital cardiac disease and their parents. Questionnaire survey in outpatient clinics at a tertiary centre dealing with congenital cardiac disease, and 6 peripheral clinics. Children or their parents completed a brief questionnaire. If this indicated a desire for help, or a serious mismatch between advised and real level of activity, they were telephoned by a physiotherapist. MAIN MEASURES OF OUTCOME: Knowledge about appropriate levels of activity, and identification of the number exercising at an unsafe level, the number seeking help, and the type of help required. 253/258 (98.0%) questionnaires were returned, with 119/253 (47.0%) showing incorrect responses in their belief about their advised level of exercise; 17/253 (6.7%) had potentially dangerous overestimation of exercise. Asked if they wanted advice 93/253 (36.8%) said "yes", 43/253 (17.0%) "maybe", and 117/253 (46.2%) "no". Of those contacted by phone to give advice, 72.7% (56/77) required a single contact and 14.3% (11/77) required an intervention that required more intensive contact lasting from 2 up to 12 weeks. Of the cohort, 3.9% (3/77) were taking part in activities that put them at significant risk. There is a significant lack of knowledge about appropriate levels of activity, and a desire for further advice, in children and young people with congenital cardiac disease. A few children may be at very significant risk. These needs can be identified, and clinical risk reduced, using a brief self-completed questionnaire combined with telephone follow-up from a suitably knowledgeable physiotherapist.

The Physician as Disability Advisor for Patients with Musculoskeletal Complaints

Literature review. To review the literature about the performance of physicians as mediators of temporary and permanent disability for patients with chronic musculoskeletal complaints. To assess specifically the nature and variance of recommendations from physicians, factors influencing physician performance, and efforts to influence physician behavior in this area. While caring for patients with musculoskeletal injuries, physicians are often asked to recommend appropriate levels of activity and work. These recommendations have significant consequences for patients' general health, employment, and financial well-being. Medical literature search. Physician recommendations limiting activity and work after injury are highly variable, often reflecting their own pain attitudes and beliefs. Patients' desires strongly predict disability recommendations (i.e., physicians often acquiesce to patients' requests). Other influences include jurisdiction, employer, insurer, and medical system factors. The most successful efforts to influence physician recommendations have used mass communication to influence public attitudes, while reinforcing the current standard of practice for physicians. Physician recommendations for work and activity have important health and financial implications. Systemic, multidimensional approaches are necessary to improve performance.

Understanding the relationship between body temperature and activity patterns in the giant Solomon Island skink, Corucia zebrata, as a contribution to the effectiveness of captive breeding programmes

The behaviour and body temperatures of the Giant Solomon Islands skink, Corucia zebrata , have been observed in a semi-naturalistic enclosure. Corucia zebrata is a non-basker that thermoregulates by selecting microhabitats where operative temperatures enable body temperatures of around 30°C to be maintained. Body temperatures were significantly higher during sunny weather, but there was no significant difference in body temperature variance. Body temperatures were significantly lower than operative temperatures in open locations or dappled sunlight, but higher than operative temperatures in shaded locations. Coefficients of determination ( r 2 ) showed that lizard body temperatures had less association with operative temperatures during sunny weather. The frequency of activity was greater in sunny weather, but the distances travelled during locomotory activity were not significantly different between weather conditions. The lizards were observed less frequently at the upper levels of the canopy during sunny weather. Enclosure design for captive animals should reflect both thermal and structural diversity to enable target body temperatures and appropriate levels of activity to be achieved. Captive breeding programmes may be the only means left for conserving C. zebrata , and information on the relationship between activity and thermal biology is crucial for effective captive breeding programmes.

How active are we? Levels of routine physical activity in children and adults.

The accurate measurement of physical activity is fraught with problems in adults, but more especially in children because they have more complex and multi-dimensional activity patterns. In addition, the results of different studies are often difficult to interpret and compare, because of the diversity of methodological approaches, differences in data analysis and reporting, and the adoption of varying definitions of what constitutes an appropriate level of activity. Furthermore, inactivity is seldom quantified directly. Although there exists an extensive literature documenting the health benefits of regular physical activity in adults, activity-health relationships in children are not clear-cut. Current recommendations reinforce the concept of health-related activity, accumulating 30 min moderate-intensity exercise on at least 5 d/week (adults) and 1 h moderate-intensity exercise/d (children). Evidence suggests a high prevalence of inactivity in adults, but whether or not inactivity is increasing cannot be assessed currently. Similarly, no definite conclusions are justified about either the levels of physical activity of children, or whether these are sufficient to maintain and promote health. Data to support the belief that activity levels in childhood track into adulthood are weak. Inactivity is associated with an increased risk of weight gain and obesity, but causality remains to be established. In children there is strong evidence to demonstrate a dose response relationship between the prevalence and incidence of obesity and time spent viewing television. Future research should focus on refining methodology for physical activity assessment to make it more sensitive to the different dimensions and contexts of activity in different age-groups.

Physical Activity in Physical Education: Pupil Activity Rating, Reason and Reality

This paper reports research that has focusedon relationships between physical activity and physical education in the United Kingdom. How teachers might involve pupils, and pupils might involve themselves, in appropriate levels of activity during physical education was explored using pupils’ perceptions of physical activity level as a focus for teaching and learning in games. The research highlighted that attempts to integrate skills, knowledge and understanding relating to physical activity with ‘other learning’ in physical education need to consider a complex range of factors that influence pupils’ understandings of, and ability to, self‐monitor their physical activity level in varied and often unpredictable activitysettings. This paper draws attentionto the need for teaching concerned with physical activity levels to engage with the broader contexts of teaching and learning in physical education, the social dynamics of lessons and schooling, and wider social issues shaping pupils’ thinking about themselves and physical activity.

Phosphoenolpyruvate carboxykinase revisited: Insights into its metabolic role

Phosphoenolpyruvate carboxykinase revisited: Insights into its metabolic role

Neuronal Activity and Brain-Derived Neurotrophic Factor Regulate the Density of Inhibitory Synapses in Organotypic Slice Cultures of Postnatal Hippocampus

Hippocampal interneurons inhibit pyramidal neurons through the release of the neurotransmitter GABA. Given the importance of this inhibition for the proper functioning of the hippocampus, the development of inhibitory synapses must be tightly regulated. In this study, the possibility that neuronal activity and neurotrophins regulate the density of GABAergic inhibitory synapses was investigated in organotypic slice cultures taken from postnatal day 7 rats. In hippocampal slices cultured for 13 d in the presence of the GABA(A) receptor antagonist bicuculline, the density of glutamic acid decarboxylase (GAD) 65-immunoreactive terminals was increased in the CA1 area when compared with control slices. Treatment with the glutamate receptor antagonist 6,7-dinitroquinoxaline-2,3-dione decreased the density of GAD65-immunoreactive terminals in the stratum oriens of CA1. These treatments had parallel effects on the density of GABA-immunoreactive processes. Electron microscopic analysis after postembedding immunogold labeling with antibodies against GABA indicated that bicuculline treatment increased the density of inhibitory but not excitatory synapses. Application of exogenous BDNF partly mimicked the stimulatory effect of bicuculline on GAD65-immunoreactive terminals. Finally, antibodies against BDNF, but not antibodies against nerve growth factor, decrease the density of GAD65-immunoreactive terminals in bicuculline-treated slices. Thus, neuronal activity regulates the density of inhibitory synapses made by postnatal hippocampal interneurons, and BDNF could mediate part of this regulation. This regulation of the density of inhibitory synapses could represent a feedback mechanism aimed at maintaining an appropriate level of activity in the developing hippocampal networks.