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Inflammation of the mammary gland following bacterial infection, commonly known as mastitis, affects all mammalian species. Although the aetiology and epidemiology of mastitis in the dairy cow are well described, the genetic factors mediating resistance to mammary gland infection are not well known, due in part to the difficulty in obtaining robust phenotypic information from sufficiently large numbers of individuals. To address this problem, an experimental mammary gland infection experiment was undertaken, using a Friesian-Jersey cross breed F2 herd. A total of 604 animals received an intramammary infusion of Streptococcus uberis in one gland, and the clinical response over 13 milkings was used for linkage mapping and genome-wide association analysis. A quantitative trait locus (QTL) was detected on bovine chromosome 11 for clinical mastitis status using micro-satellite and Affymetrix 10 K SNP markers, and then exome and genome sequence data used from the six F1 sires of the experimental animals to examine this region in more detail. A total of 485 sequence variants were typed in the QTL interval, and association mapping using these and an additional 37 986 genome-wide markers from the Illumina SNP50 bovine SNP panel revealed association with markers encompassing the interleukin-1 gene cluster locus. This study highlights a region on bovine chromosome 11, consistent with earlier studies, as conferring resistance to experimentally induced mammary gland infection, and newly prioritises the IL1 gene cluster for further analysis in genetic resistance to mastitis.
Optimal carbohydrate ingestion strategies as nutritional therapy for glycogen storage diseases have not been fully realised, in part, due to difficulties in accessing patient cohorts, alongside limited details on metabolic effects and insight into working mechanisms. The present pilot study compared glycaemic and fuel oxidation responses following the ingestion of a hydrothermally processed maize starch (HPMS), an uncooked maize starch (UCMS) and maize-derived dextrose (DEX) at rest and during and after exercise in healthy individuals. A total of eight participants (seven males and one female; body mass (BM) 76·9 (sem 5·2) kg) visited the laboratory on three occasions. During each visit, the participants ingested 1 g/kg BM of HPMS (Glycosade™), UCMS (Argo™) or DEX as a 10 % solution. Blood samples were collected over a 2 h rest period and for 2 h after a 60 min treadmill run at 65 (sem 1) % VO2max. Mean values with their standard errors were analysed using repeated-measures ANOVA. Blood glucose concentrations under the HPMS condition were significantly elevated from resting values at 90 min (P= 0·02) after ingestion compared with those under the UCMS (60 min; P= 0·02) and DEX (30 min; P= 0·001) conditions. The rate of carbohydrate use during exercise after the ingestion of HPMS was 7–9 % lower compared with that after the ingestion of either DEX or UCMS (P< 0·05). The total amount of lipids oxidised during exercise was greater under the HPMS condition (26·2 (sem 2·8) g) compared with that oxidised under the UCMS (19·6 (sem 2·7) g; P= 0·04) or DEX (20·6 (sem 3·6) g; P= 0·07) condition. The results demonstrated a glycaemic advantage to the ingestion of HPMS over that of UCMS or DEX. Carbohydrate oxidation was reduced after the ingestion of HPMS compared with that after the ingestion of UCMS or DEX, with a corresponding higher rate of endogenous lipid use during exercise.
Microelectromechanical Systems (MEMS) are being extensively investigated as a means of miniaturizing piezoelectric sensors thereby offering higher sensitivity, reduced power consumption, and ability to form compact multi-sensor arrays. Such devices typically employ one or more silicon micromechanical elements (e.g. membranes, cantilever beams and tethered proof masses) driven electromechanically by a polycrystalline piezoelectric film. The use of polycrystalline materials results in inherently less stable and irreproducible device characteristics. For elevated operating temperatures, more robust and refractory materials are also required. In this paper, we describe a MEMS microresonator array capable of operating to temperatures exceeding 600°C enabled by the integration of epitaxially grown piezoelectric AlN films onto single crystal SiC tethered plates. The operation of the microresonators as sensors is illustrated by examining their response to temperature, pressure and chemical analytes.
Nanocrystalline Ni0.5Zn0.5Fe2O4 thin films have been synthesized with various grain sizes by sol–gel method on polycrystalline silicon substrates. The morphology and microwave absorption properties of the films calcined in the 673–1073 K range were studied by using XRD, AFM, near–field evanescent microwave microscopy, coplanar waveguide and direct microwave heating measurements. All films were uniform without microcracks. The increase of the calcination temperature from 873 to 1073 K and time from 1 to 3h resulted in an increase of the grain size from 12 to 27 nm. The complex permittivity of the Ni-Zn ferrite films was measured in the frequency range of 2–15 GHz. The heating behavior was studied in a multimode microwave cavity at 2.4 GHz. The highest microwave heating rate in the temperature range of 315–355 K was observed in the film close to the critical grain size of 21 nm in diameter marked by the transition from single– to multi–domain structure of nanocrystals in Ni0.5Zn0.5Fe2O4 film and by a maximum in its coercivity.
Lab-on-a-chip (LOC) is one of the most important microsystem applications with promise for use in microanalysis, drug development, diagnosis of illness and diseases etc. LOC typically consists of two main components: microfluidics and sensors. Integration of microfluidics and sensors on a single chip can greatly enhance the efficiency of biochemical reactions and the sensitivity of detection, increase the reaction/detection speed, and reduce the potential cross-contamination, fabrication time and cost etc. However, the mechanisms generally used for microfluidics and sensors are different, making the integration of the two main components complicated and increases the cost of the systems. A lab-on-a-chip system based on a single surface acoustic wave (SAW) actuation mechanism is proposed. SAW devices were fabricated on nanocrystalline ZnO thin films deposited on Si substrates using sputtering. Coupling of acoustic waves into a liquid induces acoustic streaming and motion of droplets. A streaming velocity up to ˜5cm/s and droplet pumping speeds of ˜1cm/s were obtained. It was also found that a higher order mode wave, the Sezawa wave is more effective in streaming and transportation of microdroplets. The ZnO SAW sensor has been used for prostate antigen/antibody biorecognition systems, demonstrated the feasibility of using a single actuation mechanism for lab-on-a-chip applications.
Planet formation theory is founded on the concept of dust coagulation and subsequent growth into planetesimals. This process is by no means an isolated one, but possibly happens in a turbulent nebula. It is therefore crucial to understand how particles of different sizes are affected by their gaseous environment via stochastic forcing and aerodynamic damping. We here report on the effects of magneto-rotational (MRI) turbulence in the presence of non-uniform ionisation leading to the formation of a magnetically inactive dead-zone. While we find that collisional growth is impeded by fully-active MRI, it may be possible within a dead-zone.
The Beck Depression Inventory-II (BDI-II) is widely used for assessing depression in neurorehabilitation. Given the concern that the somatic items might be misleading, we examined its factor structure in 353 inpatients. Exploratory factor analysis was undertaken to compare two- to five-factor solutions. Confirmatory factor analysis was then used to test the best exploratory solutions for goodness of fit on a subsample. Both provided strong support for a general depression factor and two specific factors, one somatic and one cognitive/affective. The BDI-II provides a meaningful score of overall depression, and it can also yield two subscores—one measuring somatic symptoms and the other measuring psychological symptoms of depression. To avoid confusing the common symptoms of neurological disability with depression in neurorehabilitation, clinicians need to consider all three scores carefully. (JINS, 2009, 15, 142–147.)
Injury to the brain and spinal cord is one of the most catastrophic and costly occurrences in the Ontario health system. The objective of the present study was to evaluate the impact of past Ontario Neurotrauma Foundation (ONF) studentships and fellowships in terms of capacity building in the neurotrauma field in Ontario.
An online, cross sectional survey amongst past recipients of studentships and fellowships that terminated prior to July 2005. Explicit data were collected on various aspects of career development including current activity, awards and publications.
Thirty-six out of 42 (86%) eligible past trainees responded; 12 (33%) were Masters students, 12 (33%) were PhD students and 12 (33%) were Post-Doctoral students. A majority of the recipients (61%) are currently involved in neurotrauma-related activities (clinical, research and teaching) in more than 20% of their time, with no substantial differences between the degree groups. Half the recipients are currently involved in neurotrauma-related research in more than 20% of their time. The awardees published 1.5 peer-review manuscripts/person-year and received multiple awards. A high majority of our recipients (86%) feel that the ONF award had a substantial impact on their career.
A high proportion of past award recipients remain involved in neurotrauma activities, especially in research. These results may lead to a cautious conclusion of the positive impact of the ONF studentships and fellowships on neurotrauma capacity building. These results should be considered in strategic planning of funding agencies similar to ONF.
The chickenpox virus (varicella zoster virus; VZV) is known to cause large and small vessel central nervous system vasculopathies that may be associated with strokes in both adults and children. We present the case of a female aged 2 years 6 months who developed a chronic progressive small-vessel vasculopathy with radiological features of moyamoya disease as a manifestation of congenital varicella syndrome. Clinically, the condition was characterized by recurrent ischaemic strokes, which were brought under control using intravenous acyclovir. The case is unique in that it is the first report of congenital varicella syndrome to occur after a maternal herpes zoster infection. Furthermore, it is the first case of symptomatic VZV infection in a child to occur after a maternal infection occurring in the third trimester of pregnancy.
We analyze the properties of quasar variability using repeated SDSS imaging data in five UV-to-far red photometric bands, accurate to 0.02 mag, for ∼13,000 spectroscopically confirmed quasars. The observed time lags span the range from 3 hours to over 3 years, and constrain the quasar variability for rest-frame time lags of up to two years, and at rest-frame wavelengths from 1000Å to 6000Å. We demonstrate that ∼66,000 SDSS measurements of magnitude differences can be described within the measurement noise by a simple function of only three free parameters. The addition of POSS data constrains the long-term behavior of quasar variability and provides evidence for a turn-over in the structure function. This turn-over indicates that the characteristic time scale for optical variability of quasars is of the order 1 year.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html
The last interglacial, commonly understood as an interval with climate as warm or warmer than today, is represented by marine isotope stage (MIS) 5e, which is a proxy record of low global ice volume and high sea level. It is arbitrarily dated to begin at approximately 130,000 yr B.P. and end at 116,000 yr B.P. with the onset of the early glacial unit MIS 5d. The age of the stage is determined by correlation to uranium–thorium dates of raised coral reefs. The most detailed proxy record of interglacial climate is found in the Vostok ice core where the temperature reached current levels 132,000 yr ago and continued rising for another two millennia. Approximately 127,000 yr ago the Eemian mixed forests were established in Europe. They developed through a characteristic succession of tree species, probably surviving well into the early glacial stage in southern parts of Europe. After ca. 115,000 yr ago, open vegetation replaced forests in northwestern Europe and the proportion of conifers increased significantly farther south. Air temperature at Vostok dropped sharply. Pulses of cold water affected the northern North Atlantic already in late MIS 5e, but the central North Atlantic remained warm throughout most of MIS 5d. Model results show that the sea surface in the eastern tropical Pacific warmed when the ice grew and sea level dropped. The essentially interglacial conditions in southwestern Europe remained unaffected by ice buildup until late MIS 5d when the forests disappeared abruptly and cold water invaded the central North Atlantic ca. 107,000 yr ago.