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Although there is growing interest in mental health problems in university students there is limited understanding of the scope of need and determinants to inform intervention efforts.
To longitudinally examine the extent and persistence of mental health symptoms and the importance of psychosocial and lifestyle factors for student mental health and academic outcomes.
Undergraduates at a Canadian university were invited to complete electronic surveys at entry and completion of their first year. The baseline survey measured important distal and proximal risk factors and the follow-up assessed mental health and well-being. Surveys were linked to academic grades. Multivariable models of risk factors and mental health and academic outcomes were fit and adjusted for confounders.
In 1530 students surveyed at entry to university 28% and 33% screened positive for clinically significant depressive and anxiety symptoms respectively, which increased to 36% and 39% at the completion of first year. Over the academic year, 14% of students reported suicidal thoughts and 1.6% suicide attempts. Moreover, there was persistence and overlap in these mental health outcomes. Modifiable psychosocial and lifestyle factors at entry were associated with positive screens for mental health outcomes at completion of first year, while anxiety and depressive symptoms were associated with lower grades and university well-being.
Clinically significant mental health symptoms are common and persistent among first-year university students and have a negative impact on academic performance and well-being. A comprehensive mental health strategy that includes a whole university approach to prevention and targeted early-intervention measures and associated research is justified.
Dairy products are sources of protein and micronutrients important in a healthy diet. The purpose of the present analysis was to estimate consumption of dairy products by Brazilians and identify contributions of dairy products to nutrient intakes.
Dairy consumption data were obtained from 24 h dietary records. Dairy products were defined as milk (including flavoured), cheese and yoghurt. Estimates of dairy product intakes were generated for all individuals, individuals in urban and rural households and for age groups 10–18 years, 19–59 years and ≥60 years. Contributions to nutrient intakes were estimated for the total sample and sub-populations.
Nationwide cross-sectional survey, 2008–2009.
Nationally representative sample of individuals aged ≥10 years in the Individual Food Intake survey, a component of the Brazilian Household Budget Survey (n 34 003).
Among individuals aged ≥10 years, per capita intake of dairy products was 142 (se 2·1) g/d. Dairy product intake was higher among individuals in urban compared with rural areas and among groups 10–18 years and ≥60 years compared with adults aged 19–59 years. Dairy products accounted for 6·1 % of daily energy intake, 7·3 % of protein, 16·9 % of saturated fat, 11·1 % and 4·3 % of total and added sugars, respectively, and 10·2–37·9 % of daily Ca, vitamin D, P, vitamin A and K.
Dairy products were substantial contributors to daily intakes of selected nutrients of concern in Brazil, although mean daily dairy product consumption was less than a typical portion. Education efforts in Brazil to raise awareness about the nutritional role of dairy foods may serve to improve overall diet quality.
Dientamoeba fragilis is a pathogenic protozoan parasite that is implicated as a cause of human diarrhoea. A case-controlled study was conducted to determine the clinical signs associated with D. fragilis infection in children presenting to a Sydney Hospital. Treatment options are also discussed. Stool specimens were collected from children aged 15 years or younger and analysed for the presence of D. fragilis. In total, 41 children were included in the study along with a control group. Laboratory diagnosis was performed by microscopy of permanently stained, fixed faecal smears and by real-time PCR. Gastrointestinal symptoms were present in 40/41 (98%) of these children with dientamoebiasis, with diarrhoea (71%) and abdominal pain (29%) the most common clinical signs. Chronic gastrointestinal symptoms were present in 2% of cases. The most common anti-microbial used for treatment was metronidazole (n=41), with complete resolution of symptoms and clearance of parasite occurring in 85% of cases. A treatment failure rate occurred in 15% of those treated with metronidazole. Follow-up treatment comprised of an additional course of metronidazole or iodoquinol was needed in order to achieve complete resolution of infection and symptoms in this group. This study demonstrates the pathogenic potential of D. fragilis in children and as such it is recommended that all laboratories must routinely test for this organism and treat if detected.
Dientamoeba fragilis is a pathogen of the human gastrointestinal tract that is a common cause of diarrhoea. A paucity of knowledge on the in vitro cultivation and cryopreservation of Dientamoeba has meant that few studies have been conducted to investigate its biology. The objective of this study was to define, for the first time, in vitro culture conditions able to support the long-term in vitro growth of Dientamoeba. Also, we aimed to define a suitable method for cryopreserving viable Dientamoeba trophozoites. A modified BD medium, TYGM-9, Loeffler's slope medium, Robinson's medium, Medium 199, Trichosel and a Tritrichomonas fetus medium were compared, using cell counts, for their ability to support the growth of D. fragilis at various temperatures and atmospheric conditions. Loeffler's slope medium supported significantly better growth compared to other media. A temperature of 42°C and a microaerophilic atmosphere were also optimum for Dientamoeba growth. To our knowledge, this is the first study to describe and compare different culture media and conditions for the growth of clinical isolates of D. fragilis. This new technology will aid the development of diagnostics for dientamoebiasis as well as facilitate large-scale sequencing projects that will fast track molecular studies on D. fragilis.
We describe a new compilation of radiocarbon age measurements performed by the NERC Radiocarbon Laboratory that is freely available to access over the World Wide Web. The database contains 1000 14C measurements performed using the liquid scintillation counting method between 1996 and 2005, and further results will be added as the information is compiled. Contextual information including sampling location and the nature of sample material is provided, alongside 14C age results and publications codes. Hypertext links provide access to the original 14C age report associated with the samples, providing additional details. The 14C measurements were originally performed for earth and environmental science NERC projects and are therefore likely to be most relevant to the Quaternary research community.
For this analytical TEM study, nonmagnetic oxygen-rich boundaries were
introduced into Co-Pt-alloy perpendicular recording media by cosputtering
Co and Pt with TiO2. Increasing the TiO2 content
resulted in changes to the microstructure and elemental distribution
within grains and boundaries in these films. EFTEM imaging was used to
generate composition maps spanning many tens of grains, thereby giving an
overall depiction of the changes in elemental distribution occurring with
increasing TiO2 content. Comparing EFTEM with spectrum-imaging
maps created by high-resolution STEM with EDXS and EELS enabled both
corroboration of EFTEM results and quantification of the chemical
composition within individual grain boundary areas. The difficulty of
interpreting data from EDXS for these extremely thin films is discussed.
Increasing the TiO2 content of the media was found to create
more uniformly wide Ti- and O-rich grain boundaries as well as Ti- and
O-rich regions within grains.
the aim of this study was to establish the rate and spectrum of psychiatric disorder among children before and after temporal lobe surgery for epilepsy. data were examined for associations between psychopathology and seizure outcome following surgery, or association between psychopathology and other variables, such as laterality of lesion, sex, cognitive level, and underlying pathology. participants were 60 children (35 males, 25 females) who had focal seizures of temporal lobe origin and who had undergone temporal lobe resection between 1992 and 1998; mean age at time of operation 10y 7mo, (sd 4y 11mo) range 7mo to 17y 11mo. mean length of follow-up was 5.1 years (sd 2.3, range 2 to 10y). twenty-eight (47%) children had undergone right temporal lobectomy. diagnosis of a psychiatric disorder was present in 50/60 (83%) children at some point, with high rates of psychiatric comorbidity. common childhood psychiatric disorders of attention-deficit–hyperactivity disorder, oppositional defiant disorder/conduct disorder, and emotional disorders were present in about 25% of children. disorders rarely seen in the general child population were over-represented: disruptive behaviour disorder – not otherwise specified (30/60 [50%]), and pervasive developmental disorder (autistic spectrum disorder; 23/60 [38%]). there was no significant relationship between pathology, sex, seizure frequency, or postoperative seizure outcome and psychiatric disorder, other than for pervasive developmental disorder. the same proportion of children had psychiatric diagnoses pre- and postoperatively (43/60 [72%] and 41/57 [72%] respectively). although mental health problems are common in children undergoing temporal lobe resection, there are few predictors of psychiatric outcome following epilepsy surgery. parents require counselling on these issues in the preoperative work-up.
For more than 15 years, the radiocarbon community has participated in a series of laboratory intercomparisons in response to the issue of comparability of measurements as perceived within the wider user communities (Scott et al. 1990; Rozanski et al. 1992; Gulliksen and Scott 1995; Scott et al. 1997). In this report, we provide an update on the current 14C laboratory intercomparison and reflect on future issues linked to the laboratory intercomparison program, not least those resulting from a significant growth in the number of accelerator mass spectrometry (AMS) facilities providing routine dating of small samples (milligram size).
This paper outlines a dating program designed to test the reproducibility of radiocarbon dates on different materials of Late-Glacial age (plant macrofossils, fossil beetle remains, and the “humic” and “humin” chemical fractions of limnic sediments) using a combination of radiometric (beta counting) and accelerator mass spectrometry (AMS) techniques. The results have implications for the design of sampling strategies and for the development of improved dating protocols, both of which are important if a high-precision 14C chronology for the Late-Glacial is to be achieved.
The ensuing paper summarizes an investigation on the effect of target microstructural morphology on resultant sputter deposited media magnetic performance. Significant differences in media magnetic coercivity were obtained from Co–Cr–Pt–Ta targets possessing the same chemistry, sputtered under identical conditions, but possessing different microstructural phase and crystallographic texture characteristics. This result was most likely caused by the difference in sputter yields for the Ta-containing phases in the two distinct target microstructures. Results support enhanced chromium segregation yielding a decrease in the intergranuler exchange energy field for the deposited thin films.
AMS radiocarbon dates were obtained from Salix herbacea leaves, Carex seeds, and bulk organic detritus from a lake sediment profile of Wisconsinan (Weichselian) Lateglacial age in SW Ireland. There is a systematic age difference between the dated series from the two types of macrofossils, with ages obtained from Salix herbacea leaves being 900 to 1500 14C years younger than those obtained from Carex seeds. The latter tend to be more in accord with dates from the total organic detritus in the lake sediment, although the bulk organic fraction invariably registered the older ages. Intact survival of the fragile Salix leaves indicates that they are unlikely to have been physically transferred within the sediment matrix and/or otherwise reworked from the surrounding catchment. Hence, these macrofossils are the more likely to be contemporaneous with the time of deposition. However, there is no significant correlation between measured 14C age and depth in the Salix values, which scatter over a range of 700 14C years. In contrast, the age/depth relationship for Carex shows a significant reversal, possibly reflecting the redeposition of these macrofossils, and therefore giving radiocarbon ages that are anomalously old. The data have important implications for the dating of lake sediment sequences by AMS radiocarbon measurement of terrestrial plant macrofossils.
For the majority of dating laboratories and their respective user communities, the journal Radiocarbon is no longer regarded as the medium for primary publication of radiocarbon measurements. In compliance with editorial policy, the emphasis has long since moved towards the publication of research papers on technological enhancements and applications of 14C as well as other cosmogenic isotopes and this has left a requirement for an alternative medium for the publication of date lists per se. In the late 1980s, an International Radiocarbon Data Base was proposed by Renee Kra (then the managing editor) but limitations in computer and communications technologies together with the inevitable financial implications meant that this timely concept could not be taken to completion. In the last year, we have taken advantage of the development of the worldwide web to compile a database of 14C age measurements of a Scottish archaeological nature which can be found at the web address http://www.historic-scotland.gov.uk/.
In this short article, we summarize some milestones in the 50-yr-long development of natural 14C measurement. In the light of this appraisal we presume to hazard some personal opinions and forecasts as to where best opportunities might lie for future gains from the continued investment in applied 14C science. The technique and the journal are one and the same in this regard.
The thin films Co81−xCr15PtxTa4 with (0002) crystallographic texture have been sputter deposited with and without substrate bias. The lattice parameter of the thin films has been determined by a combination of x-ray diffraction and electron diffraction techniques. The resolution of the electron diffraction was enhanced by a digital imaging technique. The variation rate of the a lattice parameter with Pt content is consistent with Vegard's law. The change in the c lattice parameter is much greater than what is expected from Vegard's law.
Background. The stress generation hypothesis proposed
by Hammen (1991) holds that depressed
individuals generate stressful conditions for themselves, which lead to
recurrence. The original test
of this hypothesis compared dependent life events in women with recurrent
depression to medical
and normal controls. Two further research questions emerged from this work:
(a) do individuals
with a history of many depressive episodes generate more dependent life
events than depressives
with fewer episodes?; and (b) what is the aetiological relevance
of any stress that may be generated?
Methods. The present research tested differences in dependent
and independent events between
depressed individuals who had experienced: (a) no previous major
depressive episodes; (b) one
previous episode; and (c) two or more previous episodes. We predicted
that, based on the stress
generation hypothesis, recurrent depressives would show more dependent
events than people
without a depression history, and that these generated stressors would
be of aetiological importance
for precipitating recurrence (i.e. severe events in the 3 months preceding
Results. Recurrent depressives experienced significantly more
total dependent events than first-onset depressives in the 12 months, but
not the 3 months, preceding their episode.
Conclusions. Although the findings supported the general premise of stress
aetiological relevance of the generated stress for recurrence requires