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Enrichment of the heavy rare earth elements (HREE) in carbonatites is rare as carbonatite petrogenesis favours the light (L)REE. We describe HREE enrichment in fenitized phonolite breccia, focusing on small satellite occurrences 1–2 km from the Songwe Hill carbonatite, Malawi. Within the breccia groundmass, a HREE-bearing mineral assemblage comprises xenotime, zircon, anatase/rutile and minor huttonite/thorite, as well as fluorite and apatite.
A genetic link between HREE mineralization and carbonatite emplacement is indicated by the presence of Sr-bearing carbonate veins, carbonatite xenoliths and extensive fenitization. We propose that the HREE are retained in hydrothermal fluids which are residually derived from a carbonatite after precipitation of LREE minerals. Brecciation provides a focusing conduit for such fluids, enabling HREE transport and xenotime precipitation in the fenite. Continued fluid–rock interaction leads to dissolution of HREE-bearing minerals and further precipitation of xenotime and huttonite/thorite.
At a maximum Y content of 3100 µg g−1, HREE concentrations in the presented example are not sufficient to constitute ore, but the similar composition and texture of these rocks to other cases of carbonatite-related HREE enrichment suggests that all form via a common mechanism linked to fenitization. Precipitation of HREE minerals only occurs where a pre-existing structure provides a focusing conduit for fenitizing fluids, reducing fluid – country-rock interaction. Enrichment of HREE and Th in fenite breccia serves as an indicator of fluid expulsion from a carbonatite, and may indicate the presence of LREE mineralization within the source carbonatite body at depth.
To develop and test–retest the reproducibility of an ethnic-specific FFQ to estimate nutrient intakes for South Asians (SA) in New Zealand (NZ).
Using culturally appropriate methods, the NZFFQ, a validated dietary assessment tool for NZ adults, was modified to include SA food items by analysing foods consumed by SA participants of the Adult Nutrition Survey, in-person audit of ethnic food stores and a web scan of ethnic food store websites in NZ. This was further refined via three focus group discussions, and the resulting New Zealand South Asian Food Frequency Questionnaire (NZSAFFQ) was tested for reproducibility.
Auckland and Dunedin, NZ.
Twenty-nine and 110 males and females aged 25–59 years of SA ethnicity participated in the focus group discussions and the test–retest, respectively.
The development phase resulted in a SA-specific FFQ comprising of 11 food groups and 180 food items. Test–retest of the NZSAFFQ showed good reproducibility between the two FFQ administrations, 6 months apart. Most reproducibility coefficients were within or higher than the acceptable range of 0·5–0·7. The lowest intraclass correlation coefficients (ICC) were observed for β-carotene (0·47), vitamin B12 (0·50), fructose (0·55), vitamin C (0·57) and selenium (0·58), and the highest ICC were observed for alcohol (0·81), iodine (0·79) and folate (0·77). The ICC for fat ranged from 0·70 for saturated fats to 0·77 for polyunsaturated fats. The ICC for protein and energy were 0·68 and 0·72, respectively.
The developed FFQ showed good reproducibility to estimate nutrient intakes and warrants the need for validation of the instrument.
To assess the relationship between food insecurity, sleep quality, and days with mental and physical health issues among college students.
An online survey was administered. Food insecurity was assessed using the ten-item Adult Food Security Survey Module. Sleep was measured using the nineteen-item Pittsburgh Sleep Quality Index (PSQI). Mental health and physical health were measured using three items from the Healthy Days Core Module. Multivariate logistic regression was conducted to assess the relationship between food insecurity, sleep quality, and days with poor mental and physical health.
Twenty-two higher education institutions.
College students (n 17 686) enrolled at one of twenty-two participating universities.
Compared with food-secure students, those classified as food insecure (43·4 %) had higher PSQI scores indicating poorer sleep quality (P < 0·0001) and reported more days with poor mental (P < 0·0001) and physical (P < 0·0001) health as well as days when mental and physical health prevented them from completing daily activities (P < 0·0001). Food-insecure students had higher adjusted odds of having poor sleep quality (adjusted OR (AOR): 1·13; 95 % CI 1·12, 1·14), days with poor physical health (AOR: 1·01; 95 % CI 1·01, 1·02), days with poor mental health (AOR: 1·03; 95 % CI 1·02, 1·03) and days when poor mental or physical health prevented them from completing daily activities (AOR: 1·03; 95 % CI 1·02, 1·04).
College students report high food insecurity which is associated with poor mental and physical health, and sleep quality. Multi-level policy changes and campus wellness programmes are needed to prevent food insecurity and improve student health-related outcomes.
Recently, many industrial exoskeletons for supporting workers in heavy physical tasks have been developed. However, the efficiency of exoskeletons with regard to physical strain reduction has not been fully proved, yet. Several laboratory and field studies have been conducted, but still more data, that cannot be obtained solely by behavioral experiments, are needed to investigate effects on the human body.
This paper presents an approach to extend laboratory and field research with biomechanical simulations using the AnyBody Modeling System. Based on a dataset recorded in a laboratory experiment with 12 participants using the exoskeleton Paexo Shoulder in an overhead task, the same situation was reproduced in a virtual environment and analyzed with biomechanical simulation.
Simulation results indicate that the exoskeleton substantially reduces muscle activity and joint reaction forces in relevant body areas. Deltoid muscle activity and glenohumeral joint forces in the shoulder were decreased between 54 and 87%. Simultanously, no increases of muscle activity and forces in other body areas were observed.
This study demonstrates how a simulation framework could be used to evaluate changes in internal body loads as a result of wearing exoskeletons. Biomechanical simulation results widely agree with experimental measurements in the previous laboratory experiment and supplement such by providing an insight into effects on the human musculoskeletal system. They confirm that Paexo Shoulder is an effective device to reduce physical strain in overhead tasks. The framework can be extended with further parameters, allowing investigations for product design and evaluation.
Dietary patterns describe the combination of foods and beverages in a diet and the frequency of habitual consumption. Better understanding of childhood dietary patterns and antenatal influences could inform intervention strategies to prevent childhood obesity. We derived empirical dietary patterns in 1142 children (average age 6·0 (sd 0·2) years) in New Zealand, whose mothers had participated in the Screening for Pregnancy Endpoints (SCOPE) cohort study and explored associations with measures of body composition. Participants (Children of SCOPE) had their diet assessed by FFQ, and dietary patterns were extracted using factor analysis. Three distinct dietary patterns were identified: ‘Healthy’, ‘Traditional’ and ‘Junk’. Associations between dietary patterns and measures of childhood body composition (waist, hip, arm circumferences, BMI, bioelectrical impedance analysis-derived body fat % and sum of skinfold thicknesses (SST)) were assessed by linear regression, with adjustment for maternal influences. Children who had higher ‘Junk’ dietary pattern scores had 0·24 (sd 0·08; 95 % CI 0·04, 0·13) cm greater arm and 0·44 (sd 0·05; 95 % CI 0·01, 0·10) cm greater hip circumferences and 1·13 (sd 0·07; 95 % CI 0·03, 0·12) cm greater SST and were more likely to be obese (OR 1·74; 95 % CI 1·07, 2·82); those with higher ‘Healthy’ pattern scores were less likely to be obese (OR 0·62; 95 % CI 0·39, 1·00). In a large mother–child cohort, a dietary pattern characterised by high-sugar and -fat foods was associated with greater adiposity and obesity risk in children aged 6 years, while a ‘Healthy’ dietary pattern offered some protection against obesity. Targeting unhealthy dietary patterns could inform public health strategies to reduce the prevalence of childhood obesity.
Lamb live weight is one of the key drivers of profitability on sheep farms. Previous studies in Ireland have estimated genetic parameters for live weight and carcass composition traits using a multi-breed population rather than on an individual breed basis. The objective of the present study was to undertake genetic analyses of three lamb live weight and two carcass composition traits pertaining to purebred Texel, Suffolk and Charollais lambs born in the Republic of Ireland between 2010 and 2017, inclusive. Traits (with lamb age range in parenthesis) considered in the analyses were: pre-weaning weight (20 to 65 days), weaning weight (66 to 120 days), post-weaning weight (121 to 180 days), muscle depth (121 to 180 days) and fat depth (121 to 180 days). After data edits, 137 402 records from 50 372 lambs across 416 flocks were analysed. Variance components were derived using animal linear mixed models separately for each breed. Fixed effects included for all traits were contemporary group, age at first lambing of the dam, parity of the dam, a gender by age of the lamb interaction and a birth type by rearing type of the lamb interaction. Random effects investigated in the pre-weaning and weaning weight analyses included animal direct additive genetic, dam maternal genetic, litter common environment, dam permanent environment and residual variances. The model of analysis for post-weaning, muscle and fat depth included an animal direct additive genetic and litter common environment effect only. Significant direct additive genetic variation existed in all cases. Direct heritability for pre-weaning weight ranged from 0.14 to 0.30 across the three breeds. Weaning weight had a direct heritability ranging from 0.17 to 0.27 and post-weaning weight had a direct heritability ranging from 0.15 to 0.27. Muscle and fat depth heritability estimates ranged from 0.21 to 0.31 and 0.15 to 0.20, respectively. Positive direct correlations were evident for all traits. Results revealed ample genetic variation among animals for the studied traits and significant differences between breeds to suggest that genetic evaluations could be conducted on a per-breed basis.
Folic acid (FA) supplementation is recommended in the periconceptional period, for the prevention of neural tube defects. Limited data are available on the folate status of New Zealand (NZ) pregnant women and its association with FA supplementation intake. Objectives were to examine the relationship between plasma folate (PF) and reported FA supplement use at 15 weeks’ gestation and to explore socio-demographic and lifestyle factors associated with PF. We used data and blood samples from NZ participants of the Screening for Pregnancy Endpoints cohort study. Healthy nulliparous women with singleton pregnancy (n 1921) were interviewed and blood samples collected. PF was analysed via microbiological assay. Of the participants, 73 % reported taking an FA supplement at 15 weeks’ gestation – of these, 79 % were taking FA as part of/alongside a multivitamin supplement. Of FA supplement users, 56 % reported consuming a daily dose of ≥800 μg; 39 % reported taking less than 400 µg/d. Mean PF was significantly higher in women reporting FA supplementation (54·6 (se 1·5) nmol/l) v. no FA supplementation (35·1 (se 1·6) nmol/l) (P<0·0001). Reported daily FA supplement dose and PF were significantly positively correlated (r 0·41; P<0·05). Younger maternal age, Pacific and Maori ethnicity and obesity were negatively associated with PF levels; vegetarianism was positively associated with PF. Reported FA supplement dose was significantly associated with PF after adjustment for socio-demographic, lifestyle confounders and multivitamin intake. The relationship observed between FA supplementation and PF demonstrates that self-reported intake is a reliable proxy for FA supplement use in this study population.
The mouth may be presented and understood in different ways, be subject to judgement by others and, as we age, may intrude on everyday life due to problems that affect oral health. However, research that considers older people's experiences concerning their mouths and teeth is limited. This paper reports on qualitative research with 43 people in England and Scotland, aged 65–91, exploring the significance of the mouth over the lifecourse. It uses the concept of ‘mouth talk’ to explore narratives of maintaining, losing and replacing teeth. Participants engaged in ‘mouth talk’ to downplay the impact of the mouth, demonstrate socially appropriate ageing, and distance themselves from ‘real’ old age by retaining a moral identity and sense of self. They also found means to challenge dominant discourses of ageing in how they spoke about missing teeth. Referring to Leder's notion of ‘dys-appearance’ and Gilleard and Higgs’ work on the social imaginary of the fourth age, the study illustrates the ways in which ‘mouth talk’ can contribute to sustaining a sense of self in later life, presenting the ageing mouth, with and without teeth, as an absent presence. It also argues for the importance of listening to stories of the mouth in order to expand understanding of people's approaches to oral health in older age.
Body condition score (BCS) is a subjective assessment of the proportion of body fat an animal possesses and is independent of frame size. There is a growing awareness of the importance of mature animal live-weight given its contribution to the overall costs of production of a sector. Because of the known relationship between BCS and live-weight, strategies to reduce live-weight could contribute to the favouring of animals with lesser body condition. The objective of the present study was to estimate the average difference in live-weight per incremental change in BCS, measured subjectively on a scale of 1 to 5. The data used consisted of 19 033 BCS and live-weight observations recorded on the same day from 7556 ewes on commercial and research flocks; the breeds represented included purebred Belclare (540 ewes), Charollais (1484 ewes), Suffolk (885 ewes), Texel (1695 ewes), Vendeen (140 ewes), as well as, crossbreds (2812 ewes). All associations were quantified using linear mixed models with the dependent variable of live-weight; ewe parity was included as a random effect. The independent variables were BCS, breed (n=6), stage of the inter-lambing interval (n=6; pregnancy, lambing, pre-weaning, at weaning, post-weaning and mating) and parity (1, 2, 3, 4 and 5+). In addition, two-way interactions were used to investigate whether the association between BCS and live-weight differed by parity, a period of the inter-lambing interval or breed. The association between BCS and live-weight differed by parity, by a period of the inter-lambing interval and by breed. Across all data, a one-unit difference in BCS was associated with 4.82 (SE=0.08) kg live-weight, but this differed by parity from 4.23 kg in parity 1 ewes to 5.82 kg in parity 5+ ewes. The correlation between BCS and live-weight across all data was 0.48 (0.47 when adjusted for nuisance factors in the statistical model), but this varied from 0.48 to 0.53 by parity, from 0.36 to 0.63 by stage of the inter-lambing interval and from 0.41 to 0.62 by breed. Results demonstrate that consideration should be taken of differences in BCS when comparing ewes on live-weight as differences in BCS contribute quite substantially to differences in live-weight; moreover, adjustments for differences in BCS should consider the population stratum, especially breed.
Semiconductors CulnSe2 (CIS) and alloys of Cu(ln,Ga)Se2 (CIGS) are often used as the light absorbing layer in thin film photovoltaic devices. These polycrystalline materials reach good conversion efficiencies despite the presence of grain boundaries, which can degrade device performance. Grain properties such as size distribution and orientation can be characterized using electron backscatter diffraction (EBSD). The EBSD method has been used extensively to determine texture and recrystallization in metal forming processes but to a lesser extent for characterization of CIGS thin film properties. This article describes measurements of grain properties for CIGS thin films grown under different reaction conditions.
Introduction: Within Manitoba, little is known about the current state of pediatric emergency department (ED) use or the state of provincial data collection. This study sought to gain a baseline understanding of pediatric ED use in Manitoba, including child demographics, visit characteristics, variation across the province, drivers of ED use, and data completeness. Methods: A retrospective cohort study was conducted using administrative data from the Manitoba Centre for Health Policy, and included all children aged 0-17 who presented to a Manitoba ED between 2011/12 and 2015/16, as identified from the Emergency Department Information System (EDIS), the National Ambulatory Care Reporting System (NACRS) and physician billing claims. Frequency of use was defined as single, intermediate (2-6 visits) and frequent (7+) and regional trends in child characteristics, ED use, acuity, presenting complaints, and discharge dispositions were observed. Ordinal logistic regression will be used to identify predictors of ED use. Results: Overall, we were able to capture 250,620 ED visits made by 172,306 children; data sources and completeness varied by year. Provincially, children under 5 years of age were the most frequent users of the ED, and use <1 year of age was highest in the North. We observed higher use among low-income children, particularly in rural mid and north, and few differences by sex. By year, the majority of children made single-use of the ED (64.48%), while fewer were classified as intermediate (34.40%) or frequent users (1.11%). Overall, the top presenting complaints were for fever (10.27%), limb complaint/trauma (7.48%), abdominal pain (5.75%), nausea and/or vomiting (4.53%) and shortness of breath (3.68%), with variation by triage level. In rural but not urban areas, mental health assessments were a top presenting complaint and primary reason for transfer to larger centres. Results of predictors of ED use are pending. Conclusion: Results from this study will provide important information about the predictors and variation of ED use by region and top causes for visit, enabling us to better tailor knowledge mobilization efforts and tool development to the local context. Identified gaps in data collection are important to address to advance our knowledge and delivery of pediatric emergency care at the provincial level.
Early detection of karyotype abnormalities, including aneuploidy, could aid producers in identifying animals which, for example, would not be suitable candidate parents. Genome-wide genetic marker data in the form of single nucleotide polymorphisms (SNPs) are now being routinely generated on animals. The objective of the present study was to describe the statistics that could be generated from the allele intensity values from such SNP data to diagnose karyotype abnormalities; of particular interest was whether detection of aneuploidy was possible with both commonly used genotyping platforms in agricultural species, namely the Applied BiosystemsTM AxiomTM and the Illumina platform. The hypothesis was tested using a case study of a set of dizygotic X-chromosome monosomy 53,X sheep twins. Genome-wide SNP data were available from the Illumina platform (11 082 autosomal and 191 X-chromosome SNPs) on 1848 male and 8954 female sheep and available from the AxiomTM platform (11 128 autosomal and 68 X-chromosome SNPs) on 383 female sheep. Genotype allele intensity values, either as their original raw values or transformed to logarithm intensity ratio (LRR), were used to accurately diagnose two dizygotic (i.e. fraternal) twin 53,X sheep, both of which received their single X chromosome from their sire. This is the first reported case of 53,X dizygotic twins in any species. Relative to the X-chromosome SNP genotype mean allele intensity values of normal females, the mean allele intensity value of SNP genotypes on the X chromosome of the two females monosomic for the X chromosome was 7.45 to 12.4 standard deviations less, and were easily detectable using either the AxiomTM or Illumina genotype platform; the next lowest mean allele intensity value of a female was 4.71 or 3.3 standard deviations less than the population mean depending on the platform used. Both 53,X females could also be detected based on the genotype LRR although this was more easily detectable when comparing the mean LRR of the X chromosome of each female to the mean LRR of their respective autosomes. On autopsy, the ovaries of the two sheep were small for their age and evidence of prior ovulation was not appreciated. In both sheep, the density of primordial follicles in the ovarian cortex was lower than normally found in ovine ovaries and primary follicle development was not observed. Mammary gland development was very limited. Results substantiate previous studies in other species that aneuploidy can be readily detected using SNP genotype allele intensity values generally already available, and the approach proposed in the present study was agnostic to genotype platform.
Pre-school nutrition-related behaviours influence diet and development of lifelong eating habits. We examined the prevalence and congruence of recommended nutrition-related behaviours (RNB) in home and early childhood education (ECE) services, exploring differences by child and ECE characteristics.
Telephone interviews with mothers. Online survey of ECE managers/head teachers.
Children (n 1181) aged 45 months in the Growing Up in New Zealand longitudinal study.
A mean 5·3 of 8 RNB were followed at home, with statistical differences by gender and ethnic group, but not socio-economic position. ECE services followed a mean 4·8 of 8 RNB, with differences by type of service and health-promotion programme participation. No congruence between adherence at home and in ECE services was found; half of children with high adherence at home attended a service with low adherence. A greater proportion of children in deprived communities attended a service with high adherence, compared with children living in the least deprived communities (20 and 12 %, respectively).
Children, across all socio-economic positions, may not experience RNB at home. ECE settings provide an opportunity to improve or support behaviours learned at home. Targeting of health-promotion programmes in high-deprivation areas has resulted in higher adherence to RNB at these ECE services. The lack of congruence between home and ECE behaviours suggests health-promotion messages may not be effectively communicated to parents/family. Greater support is required across the ECE sector to adhere to RNB and promote wider change that can reach into homes.
Accurate genomic analyses are predicated on access to a large quantity of accurately genotyped and phenotyped animals. Because the cost of genotyping is often less than the cost of phenotyping, interest is increasing in generating genotypes for phenotyped animals. In some instances this may imply the requirement to genotype older animals with greater phenotypic information content. Biological material for these older informative animals may, however, no longer exist. The objective of the present study was to quantify the ability to impute 11 129 single nucleotide polymorphism (SNP) genotypes of non-genotyped animals (in this instance sires) from the genotypes of their progeny with or without including the genotypes of the progenys’ dams (i.e. mates of the sire to be imputed). The impact on the accuracy of genotype imputation by including more progeny (and their dams’) genotypes in the imputation reference population was also quantified. When genotypes of the dams were not available, genotypes of 41 sires with at least 15 genotyped progeny were used for the imputation; when genotypes of the dams were available, genotypes of 21 sires with at least 10 genotyped progeny were used for the imputation. Imputation was undertaken exploiting family and population level information. The mean and variability in the proportion of genotypes per individual that could not be imputed reduced as the number of progeny genotypes used per individual increased. Little improvement in the proportion of genotypes that could not be imputed was achieved once genotypes of seven progeny and their dams were used or genotypes of 11 progeny without their respective dam’s genotypes were used. Mean imputation accuracy per individual (depicted by both concordance rates and correlation between true and imputed) increased with increasing progeny group size. Moreover, the range in mean imputation accuracy per individual reduced as more progeny genotypes were used in the imputation. If the genotype of the mate of the sire was also used, high accuracy of imputation (mean genotype concordance rate per individual of 0.988), with little additional benefit thereafter, was achieved with seven genotyped progeny. In the absence of genotypes on the dam, similar imputation accuracy could not be achieved even using genotypes on up to 15 progeny. Results therefore suggest, at least for the SNP density used in the present study, that it is possible to accurately impute the genotypes of a non-genotyped parent from the genotypes of its progeny and there is a benefit of also including the genotype of the sire’s mate (i.e. dam of the progeny).
The objective of the present study was to quantify the extent of genetic variation in three health-related traits namely dagginess, lameness and mastitis, in an Irish sheep population. Each of the health traits investigated pose substantial welfare implications as well as considerable economic costs to producers. Data were also available on four body-related traits, namely body condition score (BCS), live weight, muscle depth and fat depth. Animals were categorised as lambs (<365 days old) or ewes (⩾365 days old) and were analysed both separately and combined. After edits, 39 315 records from 264 flocks between the years 2009 and 2015 inclusive were analysed. Variance components were estimated using animal linear mixed models. Fixed effects included contemporary group, represented as a three-way interaction between flock, date of inspection and animal type (i.e. lamb, yearling ewe (i.e. females ⩾365 days but <730 days old that have not yet had a recorded lambing) or ewe), animal breed proportion, coefficients of heterosis and recombination, animal gender (lambs only), animal parity (ewes only; lambs were assigned a separate ‘parity’) and the difference in age of the animal from the median of the respective parity/age group. An additive genetic effect and residual effect were both fitted as random terms with maternal genetic and non-genetic components also considered for traits of the lambs. The direct heritability of dagginess was similar across age groups (0.14 to 0.15), whereas the direct heritability of lameness ranged from 0.06 (ewes) to 0.12 (lambs). The direct heritability of mastitis was 0.04. For dagginess, 13% of the phenotypic variation was explained by dam litter, whereas the maternal heritability of dagginess was 0.05. The genetic correlation between ewe and lamb dagginess was 0.38; the correlation between ewe and lamb lameness was close to zero but was associated with a large standard error. Direct genetic correlations were evident between dagginess and BCS in ewes and between lameness and BCS in lambs. The present study has demonstrated that ample genetic variation exists for all three health traits investigated indicating that genetic improvement is indeed possible.
Climate change is a growing international concern, and it is well established that the release of greenhouse gases (GHG) is a contributing factor. So far, within animal production, there is little or no concerted effort on long-term breeding strategies to mitigate against GHG from ruminants. In recent years, several consortia have been formed to collect and combine data for genetic evaluation. The discussion areas of these consortia focus on (1) What are methane-determining factors, (2) What are genetic parameters for methane emissions, (3) What proxies can be used, and what is their association with methane emission, and (4) How to move on with breeding for lower emitting animals? The methane-determining factors can be divided into four groups: (1) rumen microbial population, (2) feed intake and diet composition, (3) host physiology and (4) host genetics. The genetic parameters show that enteric methane is a heritable trait, and that it is highly genetically correlated with dry matter intake. So far, the most useful proxies relate to feed intake, milk mid IR spectral data and fatty acids in the milk. To be able to move on with a genetic evaluation and ranking of animals for methane emission, it is crucial to make measurements on commercial farms. In order to make that possible, it will be necessary to develop phenotypes that can be used by the farmer to optimise the production on farm level. Also, it is crucial to develop equipment that makes it possible to make measurements without interfering with everyday routines or identify proxies that are highly related to methane and which could easily be measured on a large scale. International collaboration is essential to make progress in this area. This is both in terms of sharing ideas, experiences and phenotypes, but also in terms of coming to a consensus regarding what phenotype to collect and to select for.
The number needed to treat (NNT) statistic was developed to facilitate the
practice of evidence-based medicine. Placebo was assumed to be
therapeutically inert when the NNT was originally conceived, but more recent
data for conditions such as major depressive disorder (MDD) suggest that the
placebo control condition can have considerable therapeutic effects.
Complications arise because the NNT calculated from randomised controlled
trials (RCTs) reflects a comparison between medication plus clinical
management and placebo plus clinical management, whereas, in the clinical
setting, physicians choose between prescribing open medication, observing a
patient over time with a supportive approach, and doing nothing. Thus, NNTs
derived from clinical trials are not directly relevant to clinical
decision-making, because they are based on control conditions that do not
exist in standard practice. Additional difficulties may arise when using
NNTs to compare alternative treatments for MDD, such as medication and
psychotherapy, since these comparisons require the control conditions upon
which the respective NNTs are based to be similar. Whereas pill placebo
conditions include intensive clinical management and elicit expectations of
improvement, attention control conditions for psychotherapy research are
less well developed. Often the effects of psychotherapy are gauged against a
wait-list control condition, which has substantially fewer therapeutic
components than a pill placebo control condition. To improve the clinical
utility of NNTs for the treatment of MDD, we advocate effectiveness studies
that include treatment conditions resembling actual clinical practice,
rather than using placebo-controlled RCTs for this purpose. Until such
studies are performed, the effect of bias in comparing NNTs across
treatments can be controlled by ensuring that the RCT control conditions
upon which the NNTs are based are comparable.
Photometric observations on the UBV system have been made of a number of optically identified radio sources. The measurements are basically of two types: (1) offset photometry with the Siding Spring 40-inch reflector of objects identified as probable quasars or N galaxies, and (2) observations with the Siding Spring 24-inch reflector of radio galaxies brighter than V = 14m.0.