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We aimed to describe the natural history of heavy episodic drinking (HED) and associated harms from adolescence to young adulthood in a large Australian population cohort study.
The Australian Temperament Project consists of mothers and babies (4–8 months) recruited from Infant Welfare Centres and followed every 2 to 4 years until age 28 years. Analyses were based on data from 1156 young people (497 male; 659 female) surveyed repeatedly at ages 16, 18, 20, 24 and 28 years. We used dual processes latent class growth analysis to estimate trajectories of HED and associated harms, employing a piecewise approach to model the hypothesized rise and subsequent fall across adolescence and the late twenties, respectively.
We identified four sex-specific trajectories and observed little evidence of maturing-out across the twenties. In males, a normative pattern of increasing HED across the twenties with little related harm was observed (40% of the male sample). Early and late starter groups that peaked in harms at age 20 years with only minor attenuation in binging thereafter were also observed (6.1% and 35%, respectively). In females, a normative pattern of increasing, but moderate, HED with little related harm was observed (44% of the female sample). Early and late starter groups were also identified (18% and 17%, respectively); however, unlike males, the female late starter group showed a pattern of increasing HED and related harms.
Continued patterns of risky alcohol use and related harms are apparent for both males and females across the twenties.
Shortening the dry period (DP) has been proposed as a strategy to improve energy balance (EB) in cows in early lactation. This study evaluated the effects of shortening the DP on milk yield (MY), EB and residual feed intake (RFI) in two breeds; Swedish Red (SR) and Swedish Holstein (SH). Cows were blocked by breed and parity and then randomly assigned to one of two treatments; short DP of 4 weeks (4W, n=43) or conventional DP of 8 weeks (8W, n=34). Cows were kept and fed under the same conditions, except for the 4 weeks when the 4W group were still lactating prepartum and thus kept with the lactating cows. Milk yield and BW were recorded and body condition score (BCS) was rated from 10 weeks prepartum to 12 weeks postpartum. Dry matter intake (DMI) was recorded for lactating cows postpartum. Milk yield was reduced by 6.75 kg/day during the first 12 weeks postpartum (P<0.001) for the 4W cows compared with 8W cows, but there was no significant difference in total MY (3724 kg compared with 3684 kg, P=0.7) when the milk produced prepartum was included. Protein content was higher in 4W cows (3.42%) than in 8W cows (3.27%) (P<0.001) postpartum. In the 8W group, cows lost more BCS after calving (P<0.05). Cows of SR breed had higher BCS than cows of SH breed (SR=3.7, SH=3.2, P<0.001), but no differences in BW were found between breed and treatment. Energy balance was improved for cows in the 4W group (P<0.001), while feed efficiency, expressed as RFI, was reduced for 4W cows than for 8W cows (5.91 compared with −5.39, P<0.01). Shortening the DP resulted in improved EB postpartum with no difference between the breeds and no milk losses when including the milk produced prepartum.
The aims of the study were to describe the patterning and persistence of anxiety and depressive symptoms from adolescence to young adulthood and to examine long-term developmental relationships with earlier patterns of internalizing behaviours in childhood.
We used parallel processes latent growth curve modelling to build trajectories of internalizing from adolescence to adulthood, using seven waves of follow-ups (ages 11–27 years) from 1406 participants of the Australian Temperament Project. We then used latent factors to capture the stability of maternal reported child internalizing symptoms across three waves of early childhood follow-ups (ages 5, 7 and 9 years), and examined relationships among these patterns of symptoms across the three developmental periods, adjusting for gender and socio-economic status.
We observed strong continuity in depressive symptoms from adolescence to young adulthood. In contrast, adolescent anxiety was not persistent across the same period, nor was it related to later depressive symptoms. Anxiety was, however, related to non-specific stress in young adulthood, but only moderately so. Although childhood internalizing was related to adolescent and adult profiles, the associations were weak and indirect by adulthood, suggesting that other factors are important in the development of internalizing symptoms.
Once established, adolescent depressive symptoms are not only strongly persistent, but also have the potential to differentiate into anxiety in young adulthood. Relationships with childhood internalizing symptoms are weak, suggesting that early adolescence may be an important period for targeted intervention, but also that further research into the childhood origins of internalizing behaviours is needed.
Light-emitting diodes (LEDs) based on the conventional III-V compound semiconductors are known to exhibit internal quantum efficiencies (IQE) that are very close to unity. Ideally, the high IQE is expected to enable electroluminescent cooling with a cooling capacity of several Watts per cm2 of emitter area. One key requirement in enabling such cooling is the ability to fabricate high quality large area LEDs. However, detailed information on the performance of relevant large area devices and their yield is extremely scarce. In this report we present data on the yield and related large area scaling of InP/InGaAs LEDs by using current-voltage measurements performed on LED wafers fabricated at five different facilities. The samples were processed to contain square shaped mesas of sizes 0.25 mm2 and 16 mm2 operating as LEDs. While most of the smaller mesas showed relatively good electrical characteristics and low leakage current densities, some of them also exhibited very large leakage currents. In addition, in some cases the large area devices exhibited large, and even almost linearly behaving leakage currents. Such information on the scaling and unidealities of diodes fabricated using established fabrication technologies is crucial for the development of the optical cooling technologies relying on large area devices.
It is important to evaluate each step in radiocarbon analysis to ensure that the whole process is as efficient and accurate as possible. Aerosol filter samples contain a myriad of carbonaceous compounds with varying resistance to oxidation. Complete combustion of the sample is thus of great importance to ensure that the graphitized sample is representative of the original filter sample. We have evaluated sealed tube combustion of μg-sized aerosol samples using different types and amounts of reagents. Successful analysis of aerosol samples as small as 20 μg C was possible following small changes to our standard on-line method. The sealed tube combustion method performs well for standard samples containing 11 μg C.
Electrical transport and microstructure of interfaces between nm-thick films of various perovskite oxides grown by pulsed laser deposition (PLD) on TiO2- terminated SrTiO3 (STO) substrates are compared. LaAlO3/STO and KTaO3/STO interfaces become quasi-2DEG after a critical film thickness of 4 unit cell layers. The conductivity survives long anneals in oxygen atmosphere. LaMnO3/STO interfaces remain insulating for all film thicknesses and NdGaO3/STO interfaces are conducting but the conductivity is eliminated after oxygen annealing. Medium-energy ion spectroscopy and scanning transmission electron microscopy detect cationic intermixing within several atomic layers from the interface in all studied interfaces. Our results indicate that the electrical reconstruction in the polar oxide interfaces is a complex combination of different mechanisms, and oxygen vacancies play an important role.
To be able to successfully measure radiocarbon with accelerator mass spectrometry (AMS) in atmospheric aerosol samples, graphitization of small sample sizes (<50 μg carbon) must provide reproducible results. At Lund University, a graphitization line optimized for small samples has been constructed. Attention has been given to minimize the reduction reactor volume and each reactor is equipped with a very small pressure transducer that enables constant monitoring of the reaction. Samples as small as 25 μg of carbon have been successfully analyzed, and the mass detection limit of the system has probably not been reached.
There is a wide array of technologically significant materials whose response to electric and magnetic fields can make or break their utility for specific applications. Often, these electrical and magnetic properties are determined by nanoscale features that can be most effectively understood through electron microscopy studies. Here, we present an overview of the capabilities for transmission electron microscopy for uncovering information about electric and magnetic properties of materials in the context of operational devices. When devices are operated during microscope observations, a wealth of information is available about dynamics, including metastable and transitional states. Additionally, because the imaging beam is electrically charged, it can directly capture information about the electric and magnetic fields in and around devices of interest. This is perhaps most relevant to the growing areas of nanomaterials and nanodevice research. Several specific examples are presented of materials systems that have been explored with these techniques. We also provide a view of the future directions for research.
We investigated the physiological and behavioural strategies by which lactating Ethiopian Somali goats endure repeated periods of water deprivation. The experiment lasted for 32 days and was divided into four periods of 8 days each. Measurements were taken during the first 4 days in each period. Seven does (W1) were watered once daily and seven does (W4) were watered once every 4th day. Rectal temperature was taken at 0800 and 1715 h. Blood samples were taken in the evening and milk samples in the morning. The goats were on pasture between 0900 to 1215 h and 1315 to 1630 h with behaviour recorded every 5 min. The does were supplemented with 300 g of concentrates per head per day. Plasma and milk osmolality were determined by freezing point depression. Plasma total protein was measured on a TS refractometer. Plasma vasopressin concentrations were analysed by radio-immunoassay. The mean daily water intake of W1 was 1897 ml compared with the calculated mean of 1075 ml in W4 (P < 0.001). The mean diurnal variation of the rectal temperature was 3.5°C in both groups. Afternoon rectal temperature in W4 during period 1 was higher than that in the W1 on the days of water deprivation (P < 0.05). With repeated periods, plasma osmolality in W4 increased less over the days of water deprivation. It was 336, 321, 311 and 306 mosm/l on the 4th day at periods 1, 2, 3 and 4, respectively. The corresponding vasopressin concentrations were 10.0, 9.2, 4.2 and 4.4 pmol/l. Total plasma protein concentration during period 1 on days 3 and 4 were higher in W4 than in W1 (P < 0.01). During the subsequent periods, it did not increase more in W4 compared with W1, but it was lower in W4 on the days after watering. W4 milk production decreased by 22% compared with W1 in all periods. With increasing days of water deprivation, the W4 goats spent less time in the sun, grazed shorter time and frequently ate cactus (Opuntia ficus-indica) as compared with W1. Results suggested that dehydrated lactating Ethiopian Somali goats economised on water by diurnal variations of rectal temperature, storing water in the extracellular fluid, by changing behaviour at grazing and by decreasing milk production.
This is the first report of a major foodborne outbreak of enterohaemorrhagic Escherichia coli (EHEC) in Sweden. It occurred among the nursing staff at a children's hospital with approximately 1600 employees. Contaminated lettuce was the most likely source of infection. Nine persons were culture-positive for Escherichia coli (E. coli) O157 and verocytotoxin-positive by PCR and a further two were verocytotoxin-positive by PCR only. All 11 EHEC-positive individuals had attended a party for approximately 250 staff members, which was held at the hospital. In a questionnaire 37 persons stated that they had symptoms consistent with EHEC infection during the weeks after the party. There was no evidence of secondary transmission from staff to patients. The value of PCR as a sensitive and fast method for diagnosis is discussed in this paper. Pulsed-field gel electrophoresis (PFGE) was used to ascertain that staff members were infected by the same clone, and that two patients with E. coli O157 infection were not.
Echocardiography and Doppler measurements were performed to investigate changes in heart dimensions and function during pregnancy, lactation and the non-pregnant, non-lactating (dry) period in dairy goats. Eight Swedish domestic goats (Capra hircus) were studied with two-dimensional (2DE), M-mode and continuous wave Doppler measurements. Cardiac dimensions did not differ between periods. The mean cardiac outputs were 35 and 28 % greater during pregnancy and lactation, respectively, vs. the dry period. Arterial blood pressure (measured by telemetry) did not differ between reproductive periods before echocardiographic measurements, but became elevated during the measurements, with the smallest rise during lactation. Heart rate was elevated during pregnancy and increased further during echocardiographic measurements, but was not elevated during the other periods. The cranial location of the heart influenced the selection of examination window and caused some difficulties in positioning the ultrasound transducer. This may have led to underestimation of the velocity trace integral and therefore to underestimation of cardiac output. However, our values were within the range of these obtained with dye- and thermodilution methods. The goats tolerated the investigations well during lactation and the dry period, but showed increased blood pressure and heart rate during pregnancy. Therefore, the non-invasive and safe echocardiographic-Doppler method appears to be a good alternative for studies of heart dimensions and function during lactation and the dry period in the dairy goat. Experimental Physiology (2001) 86.1, 93-99.
An experiment is described which was undertaken specifically to provide CFD validation data for the case of transonic flow over nozzle afterbodies. The tests were undertaken with the AGARD standard 10° and 15° axisymmetric boat-tail geometries. Onset Mach numbers in the range 0·80-0·99 and subsonic and under-expanded jet plumes were employed in the tests. Test conditions were selected which provided a range of afterbody flow features from largely attached to shock-induced separated flows. A uniquely detailed set of surface pressure and flowfield data are presented. The flow data were acquired with a two-component laser Doppler anemometer (LDA) and define the mean and fluctuating flow components at about 500 spatial locations for each of these complex transonic flowfields. Additional information was recorded which fully defines the required computational boundary conditions.
Also presented is a detailed study of the necessary attributes of windtunnel CFD validation data. It is demonstrated that relatively high blockage experiments using cost-effective windtunnels can be used to generate CFD validation data if proper account is taken of the model/tunnel interference.
As a result of more intensive rearing and specialization in modern production, pigs are often moved to a new location. In addition, mixing of previously unacquainted pigs usually occurs following transportation to new facilities. Mixing of pigs results in agonistic behaviour (Ewbank, 1976) eliciting social stress (Arnone and Dantzer, 1980) that may produce gastro-intestinal disturbances which adversely affect pig performance.
The Study of Cenozoic planktonic foraminifera has benefited in the last 1–1/2 decades by Deep Sea Drilling retrieval of many cored sections from the major ocean basins of the world. The stratigraphy of planktonic foraminiferal species in these ocean basins has provided important data on evolutionary lineages of species and biostratigraphic utility of species. The geographic coverage of the oceans has given a clearer picture of the biogeography of species and of past oceanographic conditions. It has become clear that the evolution of planktonic foraminifera was controlled by oceanographic and climatic events related to the redistribution of land and sea. The purpose of this presentation is to summarize the major patterns of the paleobiogeography of planktonic foraminifera during the Cenozoic.
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