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High-temperature superconducting (HTS) non-insulated (NI) coils have the unique capability to bypass current through conductive turn-to-turn contacts, mitigating the possibility of a catastrophic failure in the event of a quench. However, this turn-to-turn conductivity leads to a significant increase in the coil decay/charging time constant. To understand this phenomenon, several modeling techniques have been proposed, including the lumped and distributed network (DN) circuit models, and more recently the finite-element (FE) models. In this paper, the decay results obtained from modeling HTS NI pancake coils using both a DN model and a 2D FE model approach are evaluated and compared. Steady-state fields, and transient charging and decay behaviors are calculated with each model and the results compared. Key differences are highlighted, including the computation speed and the capturing of various physical phenomena. Both models exhibit non-exponential decay during initial coil discharge due to current redistribution between the inner and outer turns. In addition, the FE model exhibits other effects arising from current redistribution in both the radial and axial directions, including remanent magnetization, and variation of the "apparent total inductance" during charging. Simulations of sudden discharge have also been analyzed using the common "lumped circuit" formula. This shows that extracted values for the apparent surface contact resistance between coil windings can differ by more than a factor of 5 from the initial input value. Our results confirms the optimal choice of architecture for future NI coil models and emphasize that caution should be exercised when interpreting experimental results using the lumped circuit approach. [ABSTRACT FROM AUTHOR]

Background: Actigraphy is often used to measure sleep in pediatric populations, despite little confirmatory evidence of the accuracy of existing sleep/wake algorithms. The aim of this study was to determine the performance of 11 sleep algorithms in relation to overnight polysomnography in children and adolescents. Methods: One hundred thirty-seven participants aged 8–16 years wore two Actigraph wGT3X-BT (wrist, waist) and three Axivity AX3 (wrist, back, thigh) accelerometers over 24-h. Gold standard measures of sleep were obtained using polysomnography (PSG; Embletta MPRPG, ST + Proxy and TX Proxy) in the home environment, overnight. Epoch by epoch comparisons of the Sadeh (two algorithms), Cole-Kripke (three algorithms), Tudor-Locke (four algorithms), Count-Scaled (CS), and HDCZA algorithms were undertaken. Mean differences from PSG values were calculated for various sleep outcomes. Results: Overall, sensitivities were high (mean ± SD: 91.8%, ± 5.6%) and specificities moderate (63.8% ± 13.8%), with the HDCZA algorithm performing the best overall in terms of specificity (87.5% ± 1.3%) and accuracy (86.4% ± 0.9%). Sleep outcome measures were more accurately measured by devices worn at the wrist than the hip, thigh or lower back, with the exception of sleep efficiency where the reverse was true. The CS algorithm provided consistently accurate measures of sleep onset: the mean (95%CI) difference at the wrist with Axivity was 2 min (-6; -14,) and the offset was 10 min (5, -19). Several algorithms provided accurate measures of sleep quantity at the wrist, showing differences with PSG of just 1–18 min a night for sleep period time and 5–22 min for total sleep time. Accuracy was generally higher for sleep efficiency than for frequency of night wakings or wake after sleep onset. The CS algorithm was more accurate at assessing sleep period time, with narrower 95% limits of agreement compared to the HDCZA (CS:-165 to 172 min; HDCZA: -212 to 250 min). Conclusion: Although the performance of existing count-based sleep algorithms varies markedly, wrist-worn devices provide more accurate measures of most sleep measures compared to other sites. Overall, the HDZCA algorithm showed the greatest accuracy, although the most appropriate algorithm depends on the sleep measure of focus. [ABSTRACT FROM AUTHOR]

A correction to the article "Validation of actigraphy sleep metrics in children aged 8 to 16 years: Considerations for device type, placement and algorithms" that was published in a 2024 issue of the journal is presented.

A high temperature superconducting (HTS) dynamo is a type of device known as a "flux pump" that can inject DC into a closed superconducting circuit. Here, we report experimental results from a variable-temperature dynamo-type HTS flux pump operated within a cryo-cooled chamber. This device employs a "continuous stator" topology, whereby an HTS "coated conductor" is wrapped to form a cylinder around a mechanical rotor such that applied flux from the rotor magnet must always penetrate the stator. This leads to a high current device that can inject >1 kA into a series-connected HTS coil at 53 K. The open-circuit DC output voltage (Voc) from this HTS dynamo has been studied at stator temperatures between 35 and 95 K and attained a maxima at a temperature ∼5 K lower than the stator Tc. At lower temperatures, Voc decreases and falls to zero below ∼40 K. This non-intuitive effect is found to be due to flux-screening by critical currents flowing with the HTS stator, which increase with decreasing temperature. These shielding currents prevent flux from penetrating the HTS stator and, hence, reduce the magnitude of locally induced emf (and thus DC output) within the HTS film. A key implication of these results is that all magnetically driven HTS flux pumps should be operated at temperatures well above their flux-screening point, and this consideration must be taken into account for future designs of multi-kA class HTS flux pumps. [ABSTRACT FROM AUTHOR]

Temporal variation in selection has long been proposed as a mechanism by which genetic variation could be maintained despite short-term strong directional selection and has been invoked to explain the maintenance of consistent individual differences in behaviour. We tested the hypothesis that ecological changes through time lead to fluctuating selection, which could promote the maintenance of variation in female behavioural traits in a wild population of North American red squirrels. As predicted, linear selection gradients on female aggression and activity significantly fluctuated across years depending on the level of competition among juveniles for vacant territories. This selection acted primarily through juvenile overwinter survival rather than maternal fecundity. Incorporating uncertainty in individual measures of behaviour reduced the magnitude of annual selection gradients and increased uncertainty in these estimates, but did not affect the overall pattern of temporal fluctuations in natural selection that coincided with the intensity of competition for vacant territories. These temporal fluctuations in selection might, therefore, promote the maintenance of heritable individual differences in behaviour in this wild red squirrel population. [ABSTRACT FROM AUTHOR]

In 2010, the Management Stream of the Australasian Child and Adolescent Obesity Research Network ( ACAORN) undertook a Delphi survey asking 'What research questions remain to be addressed in the effective management of child and adolescent obesity?' Members of ACAORN, the Child and Adolescent Obesity Clinics of Australasia Network ( CAOCOA- Net) and attendees at the Child Obesity symposium at the annual scientific meeting for the Australian and New Zealand Obesity Society ( ANZOS) contributed to three rounds of survey development. Although reasonable concordance in ratings was evident for all 10 questions, 'determining the best strategies for long-term weight management' and 'how best to support the primary healthcare system to achieve these strategies' were clearly identified as the highest research priorities. Other priorities included 'how best to identify the right children with whom to intervene' and 'managing factors which impact on service delivery'. Identifying priority research areas from those working in the field offers the opportunity to stimulate research collaboration and provide justification for funding applications. [ABSTRACT FROM AUTHOR]

What is already known about this subject Factors associated with children's body mass index (BMI) include parents' BMIs, birth weight, maternal smoking, sleep duration and television watching., Few studies have attempted to quantify either changes in the association between risk factors and BMI or the contribution of changes in the risk factors to increases in BMI over a generation., What this study adds The magnitude of the association between most risk factors and children's BMIs has not changed over a 29-year period., Increases in the population level of mothers' body mass index (BMI) explains ∼20% of the increase in children's BMI whereas the smaller increase in fathers' BMI contributes only 6%., Maternal smoking, despite the decrease in prevalence, contributes ∼17%., Objective Using two cohorts born 29 years apart in Dunedin, New Zealand we aim to examine changes in risk factors and their associations with body mass index ( BMI) at ages 3 and 7 years, and estimate their contribution to the secular changes in BMI at age 7 years. Methods Birth weight and anthropometric measures at ages 3, 5 and 7 years were obtained for 974 participants in the Dunedin Multidisciplinary Health and Development Study ( DMHDS), born in 1972-1973, and 241 in the Family Lifestyle, Activity, Movement and Eating Study ( FLAME), born in 2001-2002. Information about maternal age, education and smoking in pregnancy, as well as breastfeeding, children's television time and time in bed, was obtained by questionnaire. Results The increase in BMI over the 29-year period was 0.84 (95% CI 0.61, 1.06) kg m−2 at age 7. A 1-unit difference in the mother's BMI was associated with a 0.06 (0.03, 0.08) kg m−2 difference in offspring in both studies; the 3.4 (2.8, 4.0) kg m−2 increase in the mothers' BMIs accounts for a change of 0.19 kg m−2 in the children's BMI. The much smaller generational increase in fathers' BMI (0.7 kg m−2) correspondingly had a more limited effect on change in child BMI over time (0.06 kg m−2). Although smoking in pregnancy decreased by 15% (8, 21) its association with BMI increased from 0.20 (−0.01, 0.42) in the DMHDS cohort to 1.24 (0.76, 1.71) kg m−2 in the FLAME cohort, contributing 0.18 kg m−2 to the increase in children's BMI. Conclusions Societal factors such as higher maternal BMI and smoking in pregnancy contribute most to the secular increase in BMI, with changes in behavioural factors, including sleep and television viewing, having little effect in this setting. [ABSTRACT FROM AUTHOR]

Consistent individual differences in behaviour, and behavioural correlations within and across contexts, are referred to as animal personalities. These patterns of variation have been identified in many animal taxa and are likely to have important ecological and evolutionary consequences. Despite their importance, genetic and environmental sources of variation in personalities have rarely been characterized in wild populations. We used a Bayesian animal model approach to estimate genetic parameters for aggression, activity and docility in North American red squirrels (Tamiasciurus hudsonicus). We found support for low heritabilities (0.08-0.12), and cohort effects (0.07-0.09), as well as low to moderate maternal effects (0.07-0.15) and permanent environmental effects (0.08-0.16). Finally, we found evidence of a substantial positive genetic correlation (0.68) and maternal effects correlation (0.58) between activity and aggression providing evidence of genetically based behavioural correlations in red squirrels. These results provide evidence for the presence of heritable variation in red squirrel behaviour, but also emphasize the role of other sources of variation, including maternal effects, in shaping patterns of variation and covariation in behavioural traits. [ABSTRACT FROM AUTHOR]

This study compared the adsorption behavior of Na+ and Ni2+ by zeolite minerals that differed only in the physical size of the nanopores in their interstitial regions. Any differences observed in the adsorption of these ions were interpreted in terms of how the physical variations of their nanopores might be involved. The adsorption strength of Ni2+ was weak with zeolite Y and ZSM-5 but strong with mordenite. The adsorption strength of Na+ was weak with zeolite Y but strong with ZSM-5 and mordenite. Even when Na+ adsorbed weakly, its adsorption strength was comparable to that of Ni2+ Similarly, when both adsorbed strongly, they both adsorbed with nearly the same strength. The adsorption reaction is a three-way competition between H+, Na+, and Ni2+ for the adsorption sites. We propose a new theory to explain the increase in adsorption by the ZSM-5 zeolite for Na+ and by mordenite for Na+ and Ni2+ The new theory states that a dehydrated inner sphere adsorbing ion will be stable if either the ion's attraction to the surface site is stronger than toward the bulk water or the ion's attraction to the bulk water is offset by hindering the presence of water in the region. This occurs when the nanopore diameters are larger than the ionic diameter of the ion but much smaller than the hydrated diameter of the ion, which occurs with interstitial cavities that are not greater than approximately 0.3 to 0.5 nm in size in at least one dimension. [ABSTRACT FROM AUTHOR]

Objective: To ascertain whether body mass index (BMI) cutoffs calculated according to age and pubertal stage are superior to BMI cutoffs calculated on the basis of age alone at correctly identifying children and adolescents with high levels of adiposity. Design: Cross-sectional study. Setting: Dunedin, a university city in New Zealand. Subjects and measurements: In total, 368 healthy Caucasian children and adolescents (179 males, 189 females) aged 8.5-15.5 y had their percentage body fat measured by dual-energy X-ray absorptiometry (DXA). High adiposity was defined as ⩾25% body fat in males and ⩾35% body fat in females. The sensitivity, specificity and areas under the receiver operating characteristic curves of two Z-score distributions of BMI were calculated for each gender. Results: Forty-nine males (27.3%) and 43 females (22.8%) had high DXA-measured percentage body fat. In all, 86% of males and females with high adiposity were correctly identified by BMI cutoffs calculated according to age alone, with 89% of males and 97% of females with low adiposity being correctly classified. Similar results were observed when BMI cutoffs utilising both age and stage of pubertal development were used; 90% of males and 88% of females with high adiposity and 92% of both males and females with low adiposity were correctly classified according to BMI. Conclusions: Categorisation of BMI according to both age and pubertal stage of development does not produce cutoffs that are superior to BMI cutoffs calculated on the basis of age alone at identifying children with high DXA-measured adiposity. Sponsorship: University of Otago and the Health Research Council, New Zealand. [ABSTRACT FROM AUTHOR]

BACKGROUND:: Dual-energy X-ray information (DXA) quantitating body fat mass and percentage fat in healthy children of preschool age is scarce. OBJECTIVE:: To study the initial variability in body composition and subsequent longitudinal changes in absolute fat mass (kg) and relative adiposity (fat percentage) in a sample of contemporary young New Zealand girls. DESIGN:: Cross-sectional study with a longitudinal component. SETTING:: University research unit. SUBJECTS:: A total of 89 Caucasian girls aged 4-5?y were recruited by advertisement at baseline and 4-y changes in body composition were evaluated in 23 of these girls. METHODS:: Total body composition was measured by DXA, height and weight by anthropometry. RESULTS:: Baseline values for fat mass varied more than values for lean mass or bone mass. Girls from the upper third of our fat percentage distribution (% fat >19.2%) had more than twice the fat mass (5.34 vs 2.31?kg, P<0.001) of those from the lowest third (% fat <15.4%). The percentage gain in fat mass over 4?y (124 (95% CI 90-163) also exceeded the percentage gain of lean mass (55 (95% CI 51-59). In data adjusted for age and height, 63.5% of the variance in percentage body fat at time 2 was explained by fat mass at time one. CONCLUSIONS:: In girls, the trajectory of fat gain appears to be established at a young age. Our results support the view that body fatness tracks strongly before puberty. Since preventing the accumulation of excessive fat is preferable to reduction of existing excessive fat stores, it is important to put in place strategies to limit excessive fat gain early in life.International Journal of Obesity (2003) 27, 410-415. doi:10.1038/sj.ijo.0802236 [ABSTRACT FROM AUTHOR]

Mitochondrial DNA (mtDNA) is the only autonomously replicating source of DNA outside the nucleus. The mitochondrial genome encodes thirteen essential polypeptides of the mitochondrial respiratory chain. Defects of the mitochondrial genome can cause severe neurological and multi-systemic disorders. In many patients there is a mixture of mutated and wild-type mtDNA in the same cell (a situation termed heteroplasmy). In these patients the ratio of mutated to wild-type mtDNA is crucial and a biochemical defect only occurs with relatively high levels of mutated mtDNA within an individual cell. This threshold also seems to be critical in the development of mtDNA disease. Since the genetic defect causes a dysfunction in the terminal stage of oxidative metabolism, there is little potential for pharmacological intervention. Molecular techniques must be developed to reverse the ratio of mutated and wild-type mtDNA. In this paper we summarise our approach using both antigenomic peptide nucleic acids and cell necrosis. [ABSTRACT FROM AUTHOR]

OBJECTIVES: To determine whether girls and boys categorized from body mass index (BMI) values as overweight or obese for their age have lower bone mineral content (BMC) or lower bone area in relation to total body weight than children of normal adiposity. DESIGN: Cross-sectional study in a university bone research unit. SUBJECTS: Two hundred girls and 136 boys aged 3-19 y recruited from the general population by advertisement. MEASUREMENTS: Total body BMC (g) and bone area (cm²) measured by dual energy X-ray absorptiometry (DXA) in relation to body weight (kg), lean tissue mass (kg) and fat mass (kg) in boys and girls of three different BMI percentile groupings: normal weight (BMI <85th percentile); overweight (85 to 94th BMI percentile); obese (≥95th BMI percentile). RESULTS: Obese children had higher BMC, bone area, and fat mass for chronological age than those of normal body weight (P<0.001). In spite of this the observed values for age-adjusted total body BMC and bone area relative to body weight were each lower than predicted values, in both overweight and obese children (2.5-10.1% less, P<0.05) than in children of lower adiposity. CONCLUSION: In overweight and obese boys and girls there is a mismatch between body weight and bone development during growth: their bone mass and bone area are low for their body weight. [ABSTRACT FROM AUTHOR]

Peptide nucleic acids (PNAs) are synthetic polynucleobase molecules, which bind to DNA and RNA with high affinity and specificity. Although PNAs have enormous potential as anti-sense agents, the success of PNA-mediated gene therapy will require efficient cellular uptake and sub-cellular trafficking. At present these mechanisms are poorly understood. To address this, we have studied the uptake of biotinylated PNAs into cultured cell lines using fluorescence confocal microscopy. In human myoblasts, initial punctate staining was followed by the release of PNAs into the cytosol and subsequent localisation and concentration in the nucleus. To determine whether PNAs could also be used as therapeutic agents for mtDNA disease, we attempted to localise PNAs to the mitochondrial matrix. When attached to the presequence peptide of the nuclear-encoded human cytochrome c oxidase (COX) subunit VIII, the biotinylated PNA was successfully imported into isolated organelles in vitro. Furthermore, delivery of the biotinylated peptide-PNA to mitochondria in intact cells was confirmed by confocal microscopy. These studies demonstrate that biotinylated PNAs can be directed across cell membranes and to a specific sub-cellular compartment within human cells – highlighting the importance of these novel molecules for human gene therapy. [ABSTRACT FROM AUTHOR]

A greenhouse experiment was carried out using a Decatur silt loam soil to assess the availability and recovery of algal nitrogen (labeled) which was previously grown in simulated inorganic‐wastewater medium by grain sorghum . Dried green or blue‐green algal biomass providing 175, 350 and 525 mg labeled N/kg of soil was used as sources of nitrogen. Application of 175, 350 and 525 mg N/Kg of soil as algal biomass resulted in the release of 73.2, 126.7 and 181.6 mg N for green and 85.9, 147.6 and 183.3 mg N for blue‐green algal biomass, respectively, via mineralization over a 6‐week period. These values correspond to 35 to 42% of total N applied as green and 35 to 49% of total N applied as blue‐green algal biomass. Grain sorghum plants assimilated 25 to 34% of total N applied as green algae and 24 to 45% as blue‐green algae during 6 weeks of growth. The application of above mentioned rates increased the shoots yield by 94, 82, and 65% for green algae and 88, 61, and 61% for blue‐green algae, respectively. No significant increase was observed for the application of algal biomass at a rate higher than 175 mg N/kg of soil. Total N uptake by grain sorghum increased significantly due to the addition of algal biomass to the soil. About 58 to 65% of total green algal N and 51 to 65% of total blue‐green algal N remained in the soil. Six to 12% of the total N applied as green algae and 4 to 11% as blue‐green algae biomass was unaccounted for. The results indicated that there was no significant difference between green and blue‐green algal biomass with regard to their use as a source of plant nutrients. The results also encourage the use of algae as cleaning microorganisms for wastewater facilities and lagoons because the harvested algal biomass may be used as a source of plant nutrients to help reduce the cost of operations. [ABSTRACT FROM PUBLISHER]

Waist-to-height ratio (WHtR) is purported to offer a simpler index of health risk than body mass index (BMI) in children as it requires no adjustment for age or sex. Little is known regarding the usefulness of WHtR in different ethnic groups. The aim of this study was to compare the WHtR cutpoints associated with BMI definitions of overweight and obesity in a nationally representative sample of New Zealand children. Height, weight and waist circumference were measured in 3006 children (51.5% male) aged 5–14 years (n=1107 Māori, n=985 Pacific and n=924 New Zealand European and Others (NZEO)). A WHtR >0.5 was more common in Pacific (43.4%) and Māori (33.1%) children than in NZEO children (20.8%, P<0.001), with 25.6% of children overall being above this cutoff. Although ethnicity influenced the relationship between BMI and WHtR (P<0.01), differences were clinically insignificant as illustrated by the similarity in WHtR values for a given BMI (WHtR of 0.47 in Māori, 0.46 in Pacific and 0.48 in European boys at the 85th BMI percentile). The present results suggest that having WHtR values >0.5 should be equally useful in evaluating cardiovascular health risks in groups of Māori, Pacific and NZEO children. [ABSTRACT FROM AUTHOR]

Provides information on mitochondrial DNA (mtDNA) disease. Presence of mitochondria in all nucleated cells, which are the principal generators of cellular adenosine triphosphate by oxidative phosphorylation and are the only location of extrachromosomal DNA within the cell; Reason why mtDNA disease is only transmitted down the maternal line; Reason why patients with mtDNA disease develop diabetes.

To determine whether gender differences in body fat could be detected in prepubertal children using dual energy X-ray absorptiometry (DEXA), body composition was measured in 20 healthy boys aged 3–8 y matched for age, height and weight with 20 healthy girls. Although boys and girls did not differ in age, height, weight, body mass index (BMI) or bone mineral content, the boys had a lower percentage of body fat (13.5±5.1 vs 20.4±6.1%, P<0.01), a lower fat mass (3.2±2.0 vs 4.9±3.1 kg, P<0.01), and a higher bone-free lean tissue mass (18.6±4.3 vs 17.0±3.5 kg, P<0.01) than the girls. Girls had approximately 50% more body fat than the boys. This is the first DEXA study to show that boys aged 3–8 y have less body fat than girls of similar age, height and weight. Thus, this technology demonstrates that significant gender differences in body composition are evident, well before the onset of puberty. [ABSTRACT FROM AUTHOR]

Background and objectives The ability of bioelectrical impedance ( BIA) to measure change in body composition in children has rarely been examined. Methods Body composition was estimated by BIA (Tanita BC-418) and dual-energy x-ray absorptiometry ( DXA) in 187 children aged 4-8 years at baseline and at 12 months. Change in body composition was compared between the two methods using mixed models. Results Estimates of change in fat mass did not differ between BIA and DXA for overweight girls (mean difference between methods, 95% confidence interval: 0.04 kg, −0.19 to 0.28) or boys (0.07 kg, −0.14 to 0.27). BIA was also able to accurately detect change in fat-free mass, with no significant differences between methods (−0.14 kg, −0.10 to 0.38 in girls and −0.07 kg, −0.35 to −0.20 in boys). Change in percentage fat produced similar estimates in both genders (0.18%, −0.82 to 0.46 in girls and 0.38%, −0.37 to 1.13 in boys). BIA/ DXA comparisons in normal weight children were also not significantly different, with the exception of percentage fat in girls, where BIA slightly underestimated change compared with DXA (0.7%, 0.02-0.37). Conclusion BIA performed well as a measure of change in body composition, providing confidence for its use as an outcome measure in children. [ABSTRACT FROM AUTHOR]

Objective: Mitochondrial disease is a disorder of energy metabolism that affects 1 in 4300 adults in the UK. Pregnancy is associated with physiological demands that have implications for energy metabolism. We were interested to know how pregnancy was affected in women with mitochondrial disease, particularly those with the most common pathogenic mutation m.3243A>G.Design: Retrospective case-comparison study.Population/setting: Sixty-seven women with genetically confirmed mitochondrial disease from the UK Mitochondrial Diseases Cohort and 69 unaffected women participated.Methods: Participants answered questionnaires regarding each of their pregnancies. Patients were divided into two groups according to genetic mutation, with those harbouring m.3243A>G comprising a single group.Main Outcome Measures: Pregnancy-related complications, mode of delivery, gestational age and birthweight of newborns.Results: Of 139 live births in the comparison group, 62 were in the m.3243A>G group and 87 were in the 'all other mutations' group. Pregnancies of women with the m.3243A>G mutation had significantly more gestational diabetes (odds ratio [OR] = 8.2, 95% CI 1.3-50.1), breathing difficulties (OR = 7.8, 95% CI 1.0-59.1) and hypertension (OR = 8.2, 95% CI 3.1-21.5) than the comparison group. Only half of the pregnancies in the m.3243A>G group had normal vaginal delivery, with emergency caesarean section accounting for 24.2% of deliveries. Babies were born significantly earlier to mothers harbouring m.3243A>G with 53.3% of them preterm (<37 weeks). These babies were also more likely to require resuscitation and admission.Conclusion: Women who carried the m.3243A>G mutation appeared to be at higher risk of complications during pregnancies, caesarean section and preterm delivery than the unaffected women or those with other forms of mitochondrial disease.Tweetable Abstract: Pregnant women with mitochondrial disease - m.3243A>G mutation - are at greatly increased risk of complications and preterm delivery. [ABSTRACT FROM AUTHOR]

Objective: To assess the validity of a short calcium food frequency questionnaire (FFQ) for use in young children.Design: Calcium intake from an estimated 4 d diet record (4DDR) was compared with the calcium intake from a 35 item FFQ specifically designed to assess habitual calcium intake and previously validated for adult women.Subjects: Forty-one girls and 26 boys aged 3-6 y recruited by advertisement for studies of nutrition and bone health.Results: Mean (s.d.) calcium intakes were 798 mg (271) and 942 mg (419) for the 4DDR and FFQ respectively, (r = 0.52). Mean difference (s.d. of difference) in calcium intake between the two methods was 144 mg (355), showing that the FFQ may estimate calcium intakes 565 mg below to 854 mg above diet record values. 84% of subjects when classified by the 4DDR fell into the same or adjacent quartiles when classified by the FFQ. Only two subjects were classified in extreme quartiles for the two methods. The FFQ correctly identified 68% of children with recorded intakes less than 800 mg.Conclusions: The short calcium FFQ tended to overestimate actual calcium intakes in young children, and would not be appropriate for determining calcium intake of individuals. However, the FFQ demonstrated good ability to classify subjects into extremes of calcium intake. Moreover, the predictive value of the FFQ in identifying children with intakes below the current recommended intake of 800 mg was reasonably high (79%). [ABSTRACT FROM AUTHOR]

Defects of the mitochondrial genome cause a wide variety of clinical disorders. Except for rare cases where surgery or transplant is indicated, there is no effective treatment for patients. Genetic-based therapies are consequently being considered. On account of the difficulties associated with mitochondrial (mt) transfection, alternative approaches whereby mitochondrial genes can be engineered and introduced into the nucleus (allotopic expression) are being attempted with some success, at least in cultured cells. Defects in the activities of multi-subunit complexes of the oxidative phosphorylation apparatus have been circumvented by the targeted expression of simple single subunit enzymes from other species (xenotopic expression). Although far from the clinic, these approaches show promise. Similarly, nuclear transfection with genes encoding restriction endonucleases or sequence-specific zinc finger-binding proteins destined for mitochondria has also proved successful in targeting mtDNA-borne pathogenic mutations. This is particularly important, as mutated mtDNA is often found in cells that also contain normal copies of the genome, a situation termed heteroplasmy. Shifting the levels of heteroplasmy towards the normal mtDNA has become the goal of a variety of invasive and non-invasive methods, which are also highlighted in this review.Gene Therapy (2008) 15, 1017–1023; doi:10.1038/gt.2008.91; published online 22 May 2008 [ABSTRACT FROM AUTHOR]

Objective:High-carbohydrate (HC)–high-fibre diets are recommended for weight loss and for treating and preventing diseases such as diabetes and cardiovascular disease. We report a randomised trial comparing high-fat (HF) and high-protein (HP) diets with the conventional approach.Research design and methods:A total of 93 overweight insulin-resistant women received advice following randomisation to HF, HP or HC dietary regimes, to achieve weight loss followed by weight maintenance over 12 months. Weight, body composition and measures of carbohydrate and lipid metabolism were investigated.Results:Retention rates were 93% for HP and 75% for HC and HF. Features of the metabolic syndrome improved in all groups during the first 6 months, to a greater extent on HF and HP than an HC. During the second 6 months the HF group had increases in waist circumference (mean difference 4.4 cm (95% CI 3.0, 5.8)), fat mass (2.3 kg (1.5, 3.1)), triglycerides (0.28 mmol/l (0.09, 0.46)) and 2 h glucose (0.70 mmol/l (0.22, 1.18)). Overall there was substantial sustained improvement in waist circumference, triglycerides and insulin in the HP group and sustained but more modest changes on HC. Dietary compliance at 12 months was poor in all groups.Conclusions:HP and HC approaches appear to be appropriate options for insulin-resistant individuals. When recommending HP diets appropriate composition of dietary fat must be ensured. HC diet recommendations must include advice regarding appropriate high-fibre, low glycaemic index foods.International Journal of Obesity (2006) 30, 342–349. doi:10.1038/sj.ijo.0803075; published online 13 September 2005 [ABSTRACT FROM AUTHOR]

No previous longitudinal studies of calcium intake, anthropometry and bone health in young children with a history of avoiding cow’s milk have been undertaken. We report the 2-year changes of a group of 46 Caucasian children (28 girls, l8 boys) aged 8.1±2.0 years (mean ± SD) who had low calcium intakes at baseline and were short in stature, with elevated body mass index, poor skeletons and lower Z scores for both areal bone mineral density (BMD, in grams per square centimeter) and volumetric density (bone mineral apparent density, BMAD, in grams per cubic centimeter), compared with a reference population of milk drinkers. At follow-up, adverse symptoms to milk had diminished and modest increases in milk consumption and calcium intake had occurred. Total body bone mineral content (BMC) and bone area assessed by dual energy X-ray absorptiometry had increased ( P<0.05), and calcium intake from all sources was associated with both these measures ( P<0.05). However, although some catch-up in height had taken place, the group remained significantly shorter than the reference population (Z scores −0.39±1.14), with elevated body mass index (Z scores 0.46±1.0). The ultradistal radius BMC Z scores remained low (−0.31±0.98). The Z scores for BMD had improved to lie within the normal range at predominantly cortical sites (33% radius, neck of femur and hip trochanter) but had worsened at predominantly trabecular sites (ultradistal radius and lumbar spine), where values lay below those of the reference group ( P<0.05). Similarly, although volumetric BMAD Z scores at the 33% radius had normalized, BMAD Z scores at the lumbar spine remained below the reference population at follow-up (−0.67±1.12, P<0.001). Our results demonstrate persisting height reduction, overweight and osteopenia at the ultradistal radius and lumbar spine in young milk avoiders over 2 years of follow-up. [ABSTRACT FROM AUTHOR]

Summary: Background: Prevalence of childhood obesity is high in developed countries, and there is a growing concern regarding increasing socio‐economic disparities. Objectives: To assess trends in the prevalence of overweight, obesity and extreme obesity among New Zealand 4‐year olds, and whether these differ by socio‐economic and ethnic groupings. Methods: A national screening programme, the B4 School Check, collected height and weight data for 75–92% of New Zealand 4‐year‐old children (n = 317 298) between July 2010 and June 2016. Children at, or above, the 85th, 95th and 99.7th percentile for age and sex adjusted body mass index (according to World Health Organization standards) were classified as overweight, obese and extremely obese, respectively. Prevalence rates across 6 years (2010/11 to 2015/16) were examined by sex, across quintiles of socio‐economic deprivation, and by ethnicity. Results: The prevalence of overweight, obesity and extreme obesity decreased by 2.2 [95% CI, 1.8–2.5], 2.0 [1.8–2.2] and 0.6 [0.4–0.6] percentage points, respectively, between 2010/2011 and 2015/2016. The downward trends in overweight, obesity and extreme obesity in the population persisted after adjustment for sex, ethnicity, deprivation and urban/rural residence. Downward trends were also observed across sex, ethnicity and deprivation groups. Conclusions: The prevalence of obesity appears to be declining in 4‐year‐old children in New Zealand across all socio‐economic and ethnic groups. [ABSTRACT FROM AUTHOR]

Summary: Background: Parental inability to recognize child overweight and physician reluctance to instigate discussion prevents behaviour change. Objective: To evaluate parental acceptance of child overweight status following screening. Methods: Interviewers used motivational interviewing or best practice care to discuss overweight status of 271 young children (BMI ≥ 85th) with parents using simple traffic‐light BMI charts. Follow‐up sessions two weeks later (n = 251, 93%) were coded qualitatively to assess parental reactions to the information (overweight diagnosis) and how it was presented (feedback condition). Results: Eight‐two percent of parents rated the charts positively with few (8–10%) feeling judged. Motivational interviewing parents viewed feedback as more empathetic (relative risk, 95% CI: 4.07, 1.64–10.09), but more uncomfortable (12.2, 1.48–100.1) than best practice care parents. Overall, 65.2% of parents accepted their child was overweight, 22.1% were ambivalent and 12.7% rejected the information. Although motivational interviewing parents were less likely to accept it (OR, 95% CI: 0.49, 0.37–0.64) and more likely to be ambivalent (2.01, 1.17–3.47), the most important predictor of acceptance was a positive experience of feedback (P < 0.001). Conclusions: Simple traffic‐light charts facilitate discussion of child overweight status with parents. Style of feedback is less relevant than ensuring a positive experience for parents to increase acceptance of the weight information. [ABSTRACT FROM AUTHOR]

Background - Although several studies have shown that an early adiposity rebound (AR) is associated with an increased risk of adult obesity, it is not clear whether the rebound in body mass index (BMI) is actually attributable to changes in body fat. Objective - To determine the changes in body composition occurring in girls during AR. Design - Body composition was measured using dual-energy x-ray absorptiometry (DXA) at baseline, year one, year two and year four in 40 girls aged 3-6 years at baseline. Dietary intake was estimated by four-day diet records and physical activity by questionnaire. Age at AR was determined by modelling. The velocity of change (% per year) in height, weight and fat and lean tissues was estimated for each subject using random coefficient models. Early AR was defined as less than five years of age and late AR as five or more years of age. Outcomes - Early and late rebounders did not differ in age, height, weight, body composition, dietary protein intake or physical activity participation at baseline. Although height velocity was similar, weight velocity was significantly higher in early compared with late rebounders (13.5% vs 10.7, P<0.001). Differences in weight velocity were entirely due to change in body fat stores; early rebounders gained body fat at more than twice the rate of late rebounders (17.1 vs 6.5%, P<0.001) whereas no differences were observed in lean mass velocity. By the age of 9 years, girls with an early AR were more than 4 kg heavier than girls with an early AR, with considerably more body fat and a greater percentage classified as overweight. Conclusions - Our study demonstrates that the differences in BMI during AR are due specifically to alterations in body fat and not to alterations in lean mass or height. [ABSTRACT FROM AUTHOR]

Presents the correction of an error made in the article on peptide nucleid acid delivery to human mitochondria for gene therapy.

Mitochondrial aminoacyl‐tRNA synthetases (mtARSs) are essential, ubiquitously expressed enzymes that covalently attach amino acids to their corresponding tRNA molecules during translation of mitochondrial genes. Deleterious variants in the mtARS genes cause a diverse array of phenotypes, many of which involve the nervous system. Moreover, distinct mutations in mtARSs often cause different clinical manifestations. Recently, the gene encoding mitochondrial tryptophanyl tRNA synthetase (WARS2) was reported to cause 2 different neurological phenotypes, a form of autosomal recessive intellectual disability and a syndrome of severe infantile‐onset leukoencephalopathy. Here, we report the case of a 17‐year‐old boy with compound heterozygous mutations in WARS2 (p.Trp13Gly, p.Ser228Trp) who presented with infantile‐onset, Levodopa‐responsive Parkinsonism at the age of 2 years. Analysis of patient‐derived dermal fibroblasts revealed decreased steady‐state WARS2 protein and normal OXPHOS content. Muscle mitochondrial studies suggested mitochondrial proliferation without obvious respiratory chain deficiencies at the age of 9 years. This case expands the phenotypic spectrum of WARS2 deficiency and emphasizes the importance of mitochondrial protein synthesis in the pathogenesis of Parkinsonism. [ABSTRACT FROM AUTHOR]

We report the case of a 2-year-old boy with seizures who developed hepatic failure shortly after commencing sodium valproate. Unexpectedly, liver function returned to normal on stopping the drug. Sequencing of the mitochondrial polymerase γ gene (POLG1) revealed four heterozygous substitutions, two of which have been identified in cases of Alpers-Huttenlocher disease. [ABSTRACT FROM AUTHOR]

Background: "Hunger training", which aims to teach people to eat only when blood glucose is below a set target, appears promising as a weight loss strategy. As the ability of participants to adhere to the rigorous protocol has been insufficiently described, we sought to determine the feasibility of hunger training, in terms of retention in the study, adherence to measuring blood glucose, and eating only when blood glucose concentrations are below a set level of 4.7 mmol/L. Method: We undertook a two-week feasibility study, utilising an adaptive design approach where the specific blood glucose cut-off was the adaptive feature. A blood glucose cut-off of 4.7 mmol/L (protocol A) was used for the first 20 participants. A priori we decided that if interim analysis revealed that this cut-off did not meet our feasibility criteria, the remaining ten participants would use an individualised cut-off based on their fasting glucose concentrations (protocol B). Results: Retention of the participants in the study was 97 % (28/29 participants), achieving our criterion of 85 %. Participants measured their blood glucose before 94 % (95 % CI 91, 98) of eating occasions (criterion 80 %). However, participants following protocol A, which used a standard blood glucose cut-off of 4.7 mmol/L, were only able to adhere to eating when blood glucose was below the prescribed level 66 % of the time, below our within-person criterion of 75 %. By contrast, those participants following protocol B (individualised cut-off) adhered to the eating protocol 84 % of the time, a significant (p = 0.010) improvement over protocol A. Conclusion: Hunger training appears to be a feasible method, at least in the short-term, when an individualised fasting blood glucose is used to indicate that a meal can begin. [ABSTRACT FROM AUTHOR]

G. R. Campbell, A. Reeve, I. Ziabreva, T. M. Polvikoski, R. W. Taylor, R. Reynolds, D. M. Turnbull and D. J. Mahad (2013) Neuropathology and Applied Neurobiology 39, 377-389 Mitochondrial DNA deletions and depletion within paraspinal muscles Aims: Although mitochondrial abnormalities have been reported within paraspinal muscles in patients with axial weakness and neuromuscular disease as well as with ageing, the basis of respiratory deficiency in paraspinal muscles is not known. This study aimed to determine the extent and basis of respiratory deficiency in paraspinal muscles from cases undergoing surgery for degenerative spinal disease and post mortem cases without a history of spinal disease, where age-related histopathological changes were previously reported. Methods: Cervical and lumbar paraspinal muscles were obtained peri-operatively from 13 patients and from six post mortem control cases (age range 18-82 years) without a neurological disease. Sequential COX/SDH (mitochondrial respiratory chain complex IV/complex II) histochemistry was performed to identify respiratory-deficient muscle fibres (lacking complex IV with intact complex II activity). Real-time polymerase chain reaction, long-range polymerase chain reaction and sequencing were used to identify and characterize mitochondrial DNA (mtDNA) deletions and determine mtDNA copy number status. Mitochondrial respiratory chain complex subunits were detected by immunohistochemistry. Results: The density of respiratory-deficient fibres increased with age. On average, 3.96% of fibres in paraspinal muscles were respiratory-deficient (range 0-10.26). Respiratory deficiency in 36.8% of paraspinal muscle fibres was due to clonally expanded mtDNA deletions. MtDNA depletion accounted for further 13.5% of respiratory deficiency. The profile of immunohistochemically detected subunits of complexes was similar in respiratory-deficient fibres with and without mtDNA deletions or mtDNA depletion. Conclusions: Paraspinal muscles appeared to be particularly susceptible to age-related mitochondrial respiratory chain defects. Clonally expanded mtDNA deletions and focal mtDNA depletion may contribute towards the development of age-related postural abnormalities. [ABSTRACT FROM AUTHOR]

Mitochondrial diseases are heterogeneous in clinical presentation and genotype. The incidence of known pathogenic mitochondrial DNA mutations in the general population is 1 in 500. Little is known about the implications of pregnancy for women with mitochondrial disease. We undertook a systematic review of the literature on mitochondrial disease in pregnancy. Ten case reports were identified. The most common complications were threatened preterm labour (5 women) and preeclampsia (4 women). Two women experienced magnesium sulphate toxicity. Pregnancy had a varied effect on mitochondrial disease with some women being asymptomatic; others developing mild symptoms such as exercise intolerance or muscle weakness which resolved postnatally; and others developed more serious, persistent symptoms such as symptomatic Wolff-Parkinson-White syndrome, persistent paraesthesia and focal segmental glomerulosclerosis. Women with mitochondrial disease appear to be at increased risk of complications during pregnancy and labour but further prospective cohort studies are needed. [ABSTRACT FROM AUTHOR]

What causes complex information technology services engagements to fail? The root cause for the failure may derive from several sources, including unclear requirements, poor project management practices, underestimation of technical complexity, not accounting for the overhead in using global labor arbitrage, and rapid scope or schedule changes. In this paper, we explore how quantifiable measures of project progress gathered at several important stages of the life cycle of a project can aid in early identification of troubled projects. Specifically, we define derived statistical measures that can be used to predict the eventual outcome of a project. These predictions are used to initiate accelerated risk mitigation plans. In addition to the discussion surrounding the prediction models, we also discuss the importance of the Bpackaging[ and presentation of the statistical data that result in the successful use of our system. Our work has been adopted and used in a project health management system that is deployed worldwide by IBM Global Business Services. [ABSTRACT FROM AUTHOR]

Leukoencephalopathies with cystic changes in the white matter on magnetic resonance imaging are aetiologically heterogeneous neurological disorders seen in children. A group of leukoencephalopathies characterised by white matter lesions progressing to multifocal cystic degeneration has been reported in various disorders, including mitochondrial enzyme deficiencies, leukodystrophies, and infectious processes. We report two patients with leukoencephalopathy showing progressive cystic changes on serial MRI, and magnetic resonance spectroscopy resembling progressive cavitating leukoencephalopathy. [ABSTRACT FROM AUTHOR]

The article focuses on the Alpha-synuclein pathology and Parkinsonism associated with POLG1 mutations and multiple mitochondrial DNA deletions. It states that the dorsal nucleus of vagus and the other brainstem and subcortical nuclei showed only mild LB pathology. The authors speculated that high levels of mtDNA deletions present in that patient may have caused premature ageing and the earlier onset of AD, which usually occurs at a more advanced age.

Cytochrome c oxidase (COX) is the terminal enzyme of the respiratory chain, with subunits originating both from the mitochondrial and nuclear genome. An eleven-year-old female presented initially with a seizure followed two months later with tonic-clonic seizures, weakness and aphasia. MRI of the cerebral hemispheres showed multiple infarcts. Previous history suggested gross and fine motor control deficits with learning difficulties. A muscle biopsy showed a specific decrease of COX staining in all fibres and pleomorphic mitochondria. Respiratory chain studies confirmed an isolated complex IV defect in muscle, whilst fibroblasts showed an initial COX activity below normal which rapidly came up to the normal range on culture. Sequencing of mtDNA revealed an heteroplasmic m.7023G>A mutation in the COX1 gene, with levels of 96% in muscle, 70% in blood and 50% in the initial skin fibroblast culture dropping to 10% in later passages. The mutation was present in a critical region of the COX11 gene, the V374M change being close to the two histidine residues His376 and His378 co-ordinating with the heme a and a[sub3], and His367 which co-ordinates a magnesium ion. This case highlights that a MELAS-like syndrome can occur with isolated COX deficiency [ABSTRACT FROM AUTHOR]

Soybean severe stunt (SSS), caused by the Soybean severe stunt virus (SSSV), is a soilborne virus disease affecting soybean (Glycine max) first described in Delaware in 1988. Lack of breeding programs directed at incorporating resistance to SSSV in new cultivar releases necessitated alternative methods of SSS control. The effect of crops in 2-year rotations on the dagger nematode (Xiphinema americanum), the putative nematode vector of SSSV, and SSS severity were examined. Two years of continuous corn or grain sorghum, wheat followed by ‘HT-5203’ soybean, or 2-year fallow, reduced both dagger nematode density in the soil and SSS severity. Crop rotation to the SSSV-tolerant HT-5203 soybean as a single crop for 2 years increased dagger nematode populations and SSS severity. Greenhouse studies indicated that corn, wheat, marigold, castor, and fallow treatments reduced dagger nematodes the most after 14 weeks compared with ‘Essex’ and HT 5203 soybean. [ABSTRACT FROM AUTHOR]

Mitochondrial DNA (mtDNA) disease is an important genetic cause of neurological disability. A variety of different clinical features are observed and one of the most common phenotypes is MELAS (Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis and Stroke-like episodes). The majority of patients with MELAS have the 3243A>G mtDNA mutation. The neuropathology is dominated by multifocal infarct-like lesions in the posterior cortex, thought to underlie the stroke-like episodes seen in patients. To investigate the relationship between mtDNA mutation load, mitochondrial dysfunction and neuropathological features in MELAS, we studied individual neurones from several brain regions of two individuals with the 3243A>G mutation using dual cytochrome c oxidase (COX) and succinate dehydrogenase (SDH) histochemistry, and Polymerase Chain Reaction Restriction Fragment Lenght Polymorphism (PCR-RFLP) analysis. We found a low number of COX-deficient neurones in all brain regions. There appeared to be no correlation between the threshold level for the 3243A>G mutation to cause COX deficiency within single neurones and the degree of pathology in affected brain regions. The most severe COX deficiency associated with the highest proportion of mutated mtDNA was present in the walls of the leptomeningeal and cortical blood vessels in all brain regions. We conclude that vascular mitochondrial dysfunction is important in the pathogenesis of the stroke-like episodes in MELAS patients. As migraine is a commonly encountered feature in MELAS, we propose that coupling of the vascular mitochondrial dysfunction with cortical spreading depression (CSD) might underlie the selective distribution of ischaemic lesions in the posterior cortex in these patients. [ABSTRACT FROM AUTHOR]

We report the case of a 2-year-old boy with seizures who developed hepatic failure shortly after commencing sodium valproate. Unexpectedly, liver function returned to normal on stopping the drug. Sequencing of the mitochondrial polymerase gamma gene (POLG1) revealed four heterozygous substitutions, two of which have been identified in cases of Alpers-Huttenlocher disease. [ABSTRACT FROM AUTHOR]