Search Results - (Author, Cooperation:M. Downes)

2015-10-31

American Association for the Advancement of Science (AAAS)

0036-8075

1095-9203

Biology

Chemistry and Pharmacology

Computer Science

Medicine

Natural Sciences in General

Physics

Animals ; Apoptosis Regulatory Proteins/metabolism ; Biosynthetic Pathways ; Burkholderia ; Burkholderia Infections/complications ; Calcium-Binding Proteins/metabolism ; Escherichia coli/*immunology ; Inflammasomes/*immunology ; Insulin-Like Growth Factor I/*metabolism ; Intestines/*microbiology ; Mice ; Mice, Inbred C57BL ; *Microbiota ; Muscle, Skeletal/*metabolism ; Phosphatidylinositol 3-Kinase/metabolism ; Proto-Oncogene Proteins c-akt/metabolism ; Salmonella Infections/complications ; Salmonella typhimurium ; Wasting Syndrome/etiology/*immunology/*microbiology

2014-07-22

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Animals ; Blood Glucose/metabolism ; Body Weight/drug effects ; Diabetes Mellitus, Experimental/drug therapy/metabolism ; Diabetes Mellitus, Type 2/metabolism ; Diet, High-Fat ; Dose-Response Relationship, Drug ; Fibroblast Growth Factor 1/administration & dosage/adverse effects/*pharmacology ; Glucose/*metabolism ; Glucose Tolerance Test ; Humans ; Insulin/*metabolism ; Insulin Resistance ; Liver/drug effects/metabolism ; Male ; Mice ; Mice, Inbred C57BL ; Mice, Obese ; Mitogens/pharmacology ; Muscle, Skeletal/drug effects/metabolism ; Receptor, Fibroblast Growth Factor, Type 1/metabolism

2011-02-04

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Cell Differentiation/genetics ; Cell Line ; Cellular Reprogramming/*genetics ; CpG Islands/genetics ; DNA Methylation/*genetics ; Embryonic Stem Cells/cytology/metabolism ; Epigenomics ; Epistasis, Genetic/*genetics ; Fibroblasts/cytology/metabolism ; Genome, Human/*genetics ; Histones/metabolism ; Humans ; Induced Pluripotent Stem Cells/cytology/*metabolism ; Trophoblasts/cytology/metabolism

2012-04-24

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Adipocytes/drug effects/metabolism/pathology ; Animals ; Base Sequence ; Cell Size/drug effects ; Diabetes Mellitus, Experimental/chemically induced/genetics/pathology ; Diet, High-Fat/adverse effects ; Fibroblast Growth Factor 1/deficiency/*genetics/*metabolism ; *Homeostasis/drug effects ; Humans ; Inflammation/genetics ; Insulin/metabolism ; Insulin Resistance ; Intra-Abdominal Fat/drug effects/*metabolism/pathology ; Male ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Necrosis/enzymology ; PPAR gamma/*metabolism ; Promoter Regions, Genetic/genetics ; Response Elements/genetics

2015-03-06

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

2015-11-19

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Adipose Tissue/*cytology/*immunology ; Aging/*immunology ; Animals ; Diabetes Mellitus, Type 2/metabolism ; Glucose/metabolism ; Inflammation/immunology/metabolism ; Insulin Resistance/*immunology ; Macrophages/immunology ; Male ; Metabolic Syndrome X/immunology/metabolism ; Mice ; Obesity/metabolism ; T-Lymphocytes, Regulatory/*cytology/*immunology

2012-03-31

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Animals ; Biological Clocks/drug effects/genetics ; Circadian Rhythm/genetics/*physiology ; Cryptochromes/deficiency/genetics/metabolism ; *Energy Metabolism/genetics ; Feedback, Physiological ; Gene Expression Regulation ; Gene Regulatory Networks/genetics ; Homeostasis/genetics ; *Lipid Metabolism/genetics ; Liver/metabolism ; Male ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Molecular Sequence Data ; Motor Activity/genetics/physiology ; Nuclear Receptor Subfamily 1, Group D, Member 1/deficiency/genetics/*metabolism ; Period Circadian Proteins/deficiency/genetics/metabolism ; Receptors, Cytoplasmic and Nuclear/deficiency/genetics/*metabolism ; Repressor Proteins/deficiency/genetics/*metabolism ; Transcriptome/genetics

2011-12-16

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Animals ; *Circadian Rhythm ; Corticosterone/blood ; Cryptochromes/genetics/*metabolism ; Dexamethasone/pharmacology ; Female ; *Gene Expression Regulation/drug effects ; Glucocorticoids/pharmacology ; Glucose Intolerance/genetics ; HEK293 Cells ; Humans ; Liver/enzymology/metabolism ; Mice ; Phosphoenolpyruvate Carboxykinase (GTP)/blood/metabolism ; Receptors, Glucocorticoid/*metabolism

2018-01-23

BMJ Publishing Group

0021-9746

1472-4146

Medicine

1077-3118

AIP Digital Archive

Physics

ZnO thin films with near perfect crystallinity have been grown epitaxially on sapphire (001) by pulsed laser deposition technique. The ω-rocking curve full width at half-maximum of the ZnO(002) peak for the films grown at 750 °C, oxygen pressure 10−5 Torr was 0.17°. The high degree of crystallinity was confirmed by ion channeling technique providing a minimum Rutherford backscattering yield of 2%–3% in the near-surface region (∼2000 Å). The atomic force microscopy revealed smooth hexagonal faceting of the ZnO films. It has been possible to deposit epitaxial AlN films of thickness 1000 Å on epi-ZnO/sapphire. Excellent crystalline properties of these epi-ZnO/sapphire heterostructures are, thus, promising for lattice-matched substrates for III–V nitride heteroepitaxy and optoelectronics devices. © 1997 American Institute of Physics.

Electronic Resource

1089-7550

AIP Digital Archive

Physics

Epitaxial films of La0.7Ca0.3MnO3 have been irradiated with 90 MeV oxygen ions at different dose values ranging from 1011–1014 ions/cm2. The structural, magnetization, and magnetotransport properties have been studied as a function of the ion dose. It is found that the properties change gradually up to a dose of 1013 ions/cm2; however, drastic changes occur when the sample is irradiated at the higher dose of 1014 ions/cm2. Specifically, this sample exhibits a large, nearly temperature independent magnetoresistance in the low temperature regime. The Rutherford backscattering channeling data bring out the presence of defects in the irradiated films. The x-ray diffraction data, the temperature dependence of resistivity and magnetization, and the low temperature magnetic hysterisis data collectively indicate the presence of two different phases in the sample irradiated at 1014 ions/cm2. The surface morphology of this film, observed by atomic force microscopy, exhibits swelling, presumably due to subsurface clustering of point defects. The observed results are analyzed in terms of point defect induced random spin disorder and its effect on the magnetotransport properties. © 1998 American Institute of Physics.

Electronic Resource

1077-3118

AIP Digital Archive

Physics

Anomalously high metal–insulator transition temperature Tp and ferromagnetic transition temperature Tc have been observed in thin films of La0.8Ca0.2MnO3. Ferromagnetic resonance signals from microwave studies are observed at room temperature (well above Tc) suggesting the presence of multiple magnetic spin systems. The Tp and Tc values are higher than that of La0.67Ca0.33MnO3 which have the highest Tp and Tc according to the bulk phase diagram. These results suggest that properties well beyond those seen in the bulk phase diagram may be achievable in thin films of the manganites. © 1999 American Institute of Physics.

Electronic Resource

1077-3118

AIP Digital Archive

Physics

Epitaxial thin films of ordered double-perovskite Sr2FeMoO6−y are deposited on (001) SrTiO3 substrates by pulsed-laser deposition using a two step growth process. Selection of growth conditions is found to lead to either highly conductive metallic thin films (residual resistivity of about 1 μΩ cm) or semiconducting films. The metallic films show a positive magnetoresistance (MR) as high as 35%, while the semiconducting films show a negative MR of −3%, at a temperature of 5 K and a field of 8 T. © 1999 American Institute of Physics.

Electronic Resource

1077-3118

AIP Digital Archive

Physics

Thin films of Ag-added La2/3Ca1/3MnO3 exhibit enhancement of several desirable characteristics over the pristine counterparts. We find that the addition of Ag results in a pronounced increase in the insulator–metal transition temperature (Tp) and ferromagnetic transition temperature (Tc). There is also a remarkable improvement in the magnetic and electrical homogeneity of the samples as indicated by narrower ferromagnetic resonance linewidths and narrower resistive transitions, respectively. The observed improvement in properties is inferred to be largely associated with improved oxygen stoichiometry of the films although microstructural effects are not ruled out. © 1999 American Institute of Physics.

Electronic Resource

1077-3118

AIP Digital Archive

Physics

High crystalline quality epitaxial GaN films with thicknesses 0.5–1.5 μm have been successfully grown directly on Al2O3(0001) substrate by pulsed laser deposition (PLD). For films grown at 950 °C, we obtained an x-ray diffraction rocking curve linewidth of 7 arc min. The ion channeling minimum yield in the near-surface region (∼2000 Å) for a 0.5 μm thick film was ∼3%–4% indicating a high degree of crystallinity. The optical absorption edge measured by UV-visible spectroscopy was sharp, and the band gap was found to be 3.4 eV. The crystalline properties of these PLD GaN films are comparable to those grown by metalorganic chemical vapor deposition and molecular beam epitaxy. © 1997 American Institute of Physics.

Electronic Resource

1077-3118

AIP Digital Archive

Physics

© 2000 American Institute of Physics.

Electronic Resource

1365-2427

Blackwell Publishing Journal Backfiles 1879-2005

Biology

SUMMARY. 〈list xml:id="l1" style="custom"〉1The vertical distribution of dissolved oxygen and inorganic nitrogen differed considerably between three stratification cycles in Lake Titicaca, a tropical lake (latitude 16°S) in the high Andes (3800 m altitude). In 1980/81 an anoxic layer of water extended from 200 to 275 m and contained high levels of NH4 but zero NO3. During the annual deep mixing period in 1981 this layer was substantially eroded, and was completely eliminated during deep-mixing in 1982.2Nitrapyrin assays of nitrification demonstrated highest activity in the surface mixed layer, lowest activity just beneath the thermocline, and then increasing nitrification rates with increasing depth towards the bottom anoxic zone. Denitrification rates were slow, but detectable, in the surficial sediments of Lake Titicaca during late 1982. Much faster rates were estimated for the periods of water column anoxia.3Lake Titicaca is a productive lake with low saturation levels of oxygen because of its high altitude. These features favour hypolimnetic anoxia, and thus denitrification which varies in magnitude from year to year.

Electronic Resource

1365-3059

Blackwell Publishing Journal Backfiles 1879-2005

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Symptomless leaves of young wheat crops collected in January and February produced, after surface-sterilization and incubation on an agar medium, perithecia typical of Leptosphaeria nodorum. Single-ascospore cultures produced pycnidia typical of Septoria nodorum, whose conidia caused necrotic lesions to develop when sprayed on wheat seedlings.

Electronic Resource

1476-4687

Nature Archives 1869 - 2009

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

[Auszug] Lake Vanda was sampled at a mid-lake deep-water site (maximum depth 68 m) during the austral summer of 1980-81. Holes were bored through the 3-3.5-m permanent ice-cap and 1-1 samples removed with a discrete-depth water sampler. The unusual temperature and salinity profiles of Lake Vanda have been ...

Electronic Resource

1438-2385

Springer Online Journal Archives 1860-2000

Process Engineering, Biotechnology, Nutrition Technology

Summary A method has been devised for the determination of nitrite at low level that is directly applicable to food or other dried matrices without prior extraction. Nitric oxide released from nitrite through the action of acetic acid is determined using a chemiluminescence analyser. The limit of detection is approximately 0.02 μg, the coefficients of variation being 5.7 and 8.2% using 0.1 and 0.05 qg of sodium nitrite, respectively. The chemiluminescence analyser response is diminished when water in excess of 0.5 ml is present in the assay system unless hydrogen bromide in acetic acid is used instead of acetic acid alone. The application of the method to the direct determination of nitrite in freeze-dried cod fish has indicated a content of 0.25 mg NaNO2 per kg, equivalent to 0.050 mg per kg of the original undried material.

Zusammenfassung Es wurde eine Methode für die Bestimmung eines niedrigen Nitrit-Niveaus entwickelt, die ohne vorherige Extraktion direkt auf Nahrungsmittel oder andere trockene Materialien anwendbar ist. Es wird das durch Einwirkung von Essigsäure aus Nitrit abgespaltene Stickstoffoxyd mit Hilfe eines Chemoluminescenz-Analysators bestimmt. Die Nachweisgrenze liegt bei ungefähr 0,02 μg, indem die Variationskoeffizienten unter Anwendung von 0,1 beziehungsweise 0,05 μg Natriumnitrit 5,7 und 8,2% betragen. Die Reaktion des Chemoluminescenz-Analysators ist in Gegenwart von mehr als 0,5 ml Wasser im Bestimmungssystem herabgesetzt, es sei denn, daß Bromwasserstoff in Essigsäure angewendet wird anstatt Essigsäure allein, dies würde, jedoch, neben der Stickstoffoxydbildung aus N-Nitrosoverbindungen noch zu Stickstoffoxydbildung aus Nitrit führen. Die Anwendung der Methode für die direkte Bestimmung von Nitrit in einer gefriergetrockneten Kabeljaufleischprobe ergab einen Gehalt von 0,25 mg Natriumnitirit per kg, der mit 0,050 mg per kg des ungetrockneten Originalmaterials äquivalent ist.

Electronic Resource