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Trialeurodes vaporariorum (Westwood, 1856) (Greenhouse whitefly) is an agricultural pest of global importance. It is associated with damage to plants during feeding and subsequent virus transmission. Yet, global phylogenetic relationships, population structure, and estimation of the rates of gene flow within this whitefly species remain largely unexplored. In this study, we obtained and filtered 227 GenBank records of mitochondrial cytochrome c oxidase I (mtCOI) sequences of T. vaporariorum, across various global locations to obtain a final set of 217 GenBank records. We further amplified and sequenced a ~750 bp fragment of mtCOI from an additional 31 samples collected from Kenya in 2014. Based on a total of 248 mtCOI sequences, we identified 16 haplotypes, with extensive overlap across all countries. Population structure analysis did not suggest population differentiation. Phylogenetic analysis indicated the 2014 Kenyan collection of samples clustered with a single sequence from the Netherlands to form a well-supported clade (denoted clade 1a) nested within the total set of sequences (denoted clade 1). Pairwise distances between sequences show greater sequence divergence between clades than within clades. In addition, analysis using migrate-n gave evidence for recent gene flow between the two groups. Overall, we find that T. vaporariorum forms a single large group, with evidence of further diversification consisting primarily of Kenyan sequences and one sequence from the Netherlands forming a well-supported clade.
Technology-based dietary assessment offers solutions to many of the limitations of traditional dietary assessment methodologies including cost, participation rates and the accuracy of data collected. The 24-h dietary recall (24HDR) method is currently the most utilised method for the collection of dietary intake data at a national level. Recently there have been many developments using web-based platforms to collect food intake data using the principles of the 24HDR method. This review identifies web- and computer-based 24HDR tools that have been developed for both children and adult population groups, and examines common design features and the methods used to investigate the performance and validity of these tools. Overall, there is generally good to strong agreement between web-based 24HDR and respective reference measures for intakes of macro- and micronutrients.
Intakes of micronutrient-rich foods are low among Indian women of reproductive age. We investigated whether consumption of a food-based micronutrient-rich snack increased markers of blood micronutrient concentrations when compared with a control snack. Non-pregnant women (n 222) aged 14–35 years living in a Mumbai slum were randomised to receive a treatment snack (containing green leafy vegetables, dried fruit and whole milk powder), or a control snack containing foods of low micronutrient content such as wheat flour, potato and tapioca. The snacks were consumed under observation 6 d per week for 12 weeks, compliance was recorded, and blood was collected at 0 and 12 weeks. Food-frequency data were collected at both time points. Compliance (defined as the proportion of women who consumed ≥ 3 snacks/week) was >85 % in both groups. We assessed the effects of group allocation on 12-week nutrient concentrations using ANCOVA models with respective 0-week concentrations, BMI, compliance, standard of living, fruit and green leafy vegetable consumption and use of synthetic nutrients as covariates. The treatment snack significantly increased β-carotene concentrations (treatment effect: 47·1 nmol/l, 95 % CI 6·5, 87·7). There was no effect of group allocation on concentrations of ferritin, retinol, ascorbate, folate or vitamin B12. The present study shows that locally sourced foods can be made into acceptable snacks that may increase serum β-carotene concentrations among women of reproductive age. However, no increase in circulating concentrations of the other nutrients measured was observed.
In the present study, structural changes in the milk protein α-lactalbumin (α-LA) and its proteolysis were investigated for the potential formation of protein–fatty acid complexes during in vivo gastric digestion. Capsule endoscopy allowed visualisation of the digestion of the test drinks, with nasogastric tubes allowing sampling of the gastric contents. A total of ten healthy volunteers had nasogastric tubes inserted into the stomach and ingested test drinks containing 50 g/l of sucrose and 25 g/l of α-LA with and without 4 g/l of oleic acid (OA). The samples of gastric contents were collected for analysis at 3 min intervals. The results revealed a rapid decrease in the pH of the stomach of the subjects. The fasting pH of 2·31 (sd 1·19) increased to a pH maxima of pH 6·54 (sd 0·29) after ingestion, with a subsequent decrease to pH 2·22 (sd 1·91) after 21 min (n 8). Fluorescence spectroscopy and Fourier transform IR spectroscopy revealed partial protein unfolding, coinciding with the decrease in pH below the isoelectric point of α-LA. The activity of pepsin in the fasting state was found to be 39 (sd 12) units/ml of gastric juice. Rapid digestion of the protein occurred: after 15 min, no native protein was detected using SDS–PAGE; HPLC revealed the presence of small amounts of native protein after 24 min of gastric digestion. Mirocam® capsule endoscopy imaging and video clips (see the online supplementary material) revealed that gastric peristalsis resulted in a heterogeneous mixture during gastric digestion. Unfolding of α-LA was observed during gastric transit; however, there was no evidence of a cytotoxic complex being formed between α-LA and OA.
There is evidence that subclinical vitamin B12 (B12) deficiency is common in India. Vegetarianism is prevalent and therefore meat consumption is low. Our objective was to explore the contribution of B12-source foods and maternal B12 status during pregnancy to plasma B12 concentrations.
Maternal plasma B12 concentrations were measured during pregnancy. Children’s dietary intakes and plasma B12 concentrations were measured at age 9·5 years; B12 and total energy intakes were calculated using food composition databases. We used linear regression to examine associations between maternal B12 status and children’s intakes of B12 and B12-source foods, and children’s plasma B12 concentrations.
South Indian city of Mysore and surrounding rural areas.
Children from the Mysore Parthenon Birth Cohort (n 512, 47·1 % male).
Three per cent of children were B12 deficient (<150 pmol/l). A further 14 % had ‘marginal’ B12 concentrations (150–221 pmol/l). Children’s total daily B12 intake and consumption frequencies of meat and fish, and micronutrient-enriched beverages were positively associated with plasma B12 concentrations (P=0·006, P=0·01 and P=0·04, respectively, adjusted for socio-economic indicators and maternal B12 status). Maternal pregnancy plasma B12 was associated with children’s plasma B12 concentrations, independent of current B12 intakes (P<0·001). Milk and curd (yoghurt) intakes were unrelated to B12 status.
Meat and fish are important B12 sources in this population. Micronutrient-enriched beverages appear to be important sources in our cohort, but their high sugar content necessitates care in their recommendation. Improving maternal B12 status in pregnancy may improve Indian children’s status.
Recent community-based research has suggested that psychotic experiences act as markers of severity of psychopathology. There has, however, been a lack of clinic-based research. We wished to investigate, in a clinical sample of adolescents referred to a state-funded mental health service, the prevalence of (attenuated or frank) psychotic experiences and the relationship with (i) affective, anxiety and behavioural disorders, (ii) multimorbid psychopathology, (iii) global functioning, and (iv) suicidal behaviour.
The investigation was a clinical case–clinical control study using semi-structured research diagnostic psychiatric assessments in 108 patients newly referred to state adolescent mental health services.
Psychotic experiences were prevalent in a wide range of (non-psychotic) disorders but were strong markers of risk in particular for multimorbid psychopathology (Z = 3.44, p = 0.001). Young people with psychopathology who reported psychotic experiences demonstrated significantly poorer socio-occupational functioning than young people with psychopathology who did not report psychotic experiences, which was not explained by multimorbidity. Psychotic experiences were strong markers of risk for suicidal behaviour. Stratified analyses showed that there was a greatly increased odds of suicide attempts in patients with a major depressive disorder [odds ratio (OR) 8.89, 95% confidence interval (CI) 1.59–49.83], anxiety disorder (OR 15.4, 95% CI 1.85–127.94) or behavioural disorder (OR 3.13, 95% CI 1.11–8.79) who also had psychotic experiences compared with patients who did not report psychotic experiences.
Psychotic experiences (attenuated or frank) are an important but under-recognized marker of risk for severe psychopathology, including multimorbidity, poor functioning and suicidal behaviour in young people who present to mental health services.
The order in self-assembled block copolymer films with hexagonal structure is compared using an image analysis method and images taken by scanning electron microscopy and atomic force microscopy. The coordinates of the centres of cylindrical elements in the assembled array are assigned using image analysis software. The method is then used to calculate the amount of elements that symmetrically overlap with another element when mapped through an origin point. Order is compared based on a single numerical value which is dependent on radial distance from the origin and the overlap tolerance value that is assigned. Samples of PS-b-PEO diblock copolymer with a range of molecular weights are compared, and it is found that the degree of ordering achieved is not related to the size of the molecule.
The length-scales at which thermal transport crosses from the diffusive to ballistic regime are of much interest particularly in the design and improvement of nano-structured materials. In this work, we demonstrate that the departure from diffusive transport has been observed in Si and GaAs using an optical transient thermal grating technique where an arbitrary, experimentally set length scale can be imposed on a material. In a transient thermal grating experiment, crossed laser pulses interfere creating a well-defined periodic absorption and temperature profile. A probe beam is diffracted from this transient grating and length-scale dependent thermal transport properties can be determined from the signal decay. As the length scale is decreased to lengths shorter than the mean free paths of heat carrying phonons, quasi-ballistic heat transport effects become apparent allowing us to map out length scales and mean free paths relevant to nondiffusive thermal transport in Si and GaAs.
The objective of the study was to identify the extent and cause of an outbreak of epidemic keratoconjunctivitis (EKC). The study design was active case finding and a case-control study of clinic patients who developed symptoms of EKC between 31 December 2005 and 31 March 2006. The main outcome measures were clinical procedures carried out and clinicians seen during clinic visit. Significantly more cases than controls had tonometry with instillation of anaesthetic drops (OR 16·5, 95% CI 3·9–145·1, P<0·01), optical coherence tomography (OR 4·7, 95% CI 1·2–21·9, P=0·01), or instillation of dilating drops by an orthoptist (OR 2·3, 95% CI 1·1–4·7, P=0·01). Significantly more cases than controls were seen by one orthoptist (OR 21·8, 95% CI 8·2–60·0, P<0·01). Transmission of EKC within the clinic was probably due to contamination of either or both the anaesthetic drops and the tonometer head in the room used by an orthoptist. A comprehensive suite of strategies is required to prevent healthcare-associated EKC.
Missions envisioned for micro air vehicles may require a high degree of autonomy to operate in unknown environments. As such, vision is a critical technology for mission capability. This paper discusses an autopilot that uses vision coupled with GPS and altitude sensors for waypoint navigation. The vision processing analyses a horizon to estimate roll and pitch information. The GPS and altitude sensors then command values to roll and pitch for navigation between waypoints. A flight test of a MAV using this autopilot demonstrates the resulting closed-loop system is able to autonomously reach several waypoints. The vehicle actually uses a telemetry link to a ground station on which all vision processing and related guidance and control is performed. Several issues, such as estimating heading to account for slow updates, are investigated to increase performance.
This study examines the acquisition of the voicing contrast in German-Spanish bilingual children, on the basis of the acoustic measurement of Voice Onset Time (VOT). VOT in four bilingual children (aged 2;0–3;0) was measured and compared to VOT in three monolingual German children (aged 1;9–2;6), and to previous literature findings in Spanish. All measurements were based on word-initial stops extracted from naturalistic speech recordings. Results revealed that the bilingual children displayed three different patterns of VOT development: 1. Delay in the phonetic realization of voicing: two bilingual children did not acquire long lag stops in German during the testing period; 2. Transfer of voicing features: one child produced German voiced stops with lead voicing and Spanish voiceless stops with long lag voicing; and 3. No cross-language influence in the phonetic realization of voicing. The relevance of the findings for cross-linguistic interaction in bilingual phonetic/phonological development is discussed.
Studies of vowel length acquisition indicate an initial stage in which phonological vowel length is random followed by a stage in which either long vowels (without codas) or short vowels and codas are produced. To determine whether this sequence of acquisition applies to a group of German-speaking children (three children aged 1;3–2;6), monosyllabic and disyllabic words were transcribed and acoustically analysed. The results did not support a stage in which vowel length was totally random. At the first time period (onset of word production to 1;7), one child's monosyllabic productions were governed by a bipositional constraint such that either long vowels, or short vowels and codas were produced. At the second (1;10 to 2;0) and third time periods (2;3 to 2;6), all three children produced target long vowels significantly longer than target short vowels. Transcription results indicated that children experienced more difficulty producing target long than short vowels. In the discussion, the findings are interpreted in terms of the representation of vowel length in children's grammars.
This study investigates acquisition of the rhyme using cross-sectional
and longitudinal data from 14 English-speaking children (aged 1;3–2;0).
It focuses on 4 questions pertaining to rhyme development, which are
motivated from current theories of prosodic acquisition: 1. Do children
make vowel length errors in early acquisition?; 2. Do children acquire
coda consonants before they learn the vowel length contrast?; 3. What
consonants are first acquired as codas?; and 4. Is there a size constraint
such that children's productions are minimally and maximally bimoraic?
The results indicate that the percentage of vowel length errors across all
children was low irrespective of the percentage of codas produced. In
particular, two children produced very few coda consonants and made
few vowel length errors, suggesting that mastery of vowel length was not
secondary to coda acquisition. With respect to coda segments, children
produced voiceless obstruents as codas before sonorants supporting
generally the claim that obstruents emerge before sonorants in coda
position. Children produced coda consonants more frequently after
short than long vowels consistent with a bimoraic size constraint in
syllable development. The paper concludes by comparing the English
findings with cross-linguistic work on vowel length acquisition.
No sensitive functional index is currently available to assess Cu status in healthy human populations. This study evaluated the effect of Cu supplementation on putative indices of Cu status in twelve women and twelve men, aged between 22 and 45 years, who participated in a double-blind placebo controlled crossover study. The study consisted of three 6-week supplementation regimens of 3 mg CuSO4, 3 mg Cu-glycine chelate and 6 mg Cu-glycine chelate, each separated by placebo periods of equal length. Women had significantly higher caeruloplasmin oxidase activity (P < 0·001), caeruloplasmin protein concentration (P < 0·05), and serum diamine oxidase activity (P < 0·01) at baseline than men. Erythrocyte and leucocyte superoxide dismutase activity, leucocyte cytochrome c oxidase activity, and erythrocyte glutathione peroxidase activity did not respond to Cu supplementation. Platelet cytochrome c oxidase activity was significantly higher (P < 0·01), after supplementation with 6 mg Cu-glycine chelate in the total group and in women but did not change in men. Caeruloplasmin oxidase activity was significantly higher (P < 0·05), in men after supplementation with 3 mg Cu-glycine chelate, while caeruloplasmin protein concentration was significantly lower in men after supplementation with 6 mg Cu-glycine chelate (P < 0·05). Serum diamine oxidase activity was significantly higher after all supplementation regimens in the total group and in both men and women (P < 0·01). These results indicate that serum diamine oxidase activity is sensitive to changes in dietary Cu intakes and may also have the potential to evaluate changes in Cu status in healthy adult human subjects.