9,184 research outputs found
Circular 20
Since fanning in Alaska first began and especially
since dairy farming became the primary agricultural
industry, there has existed a need for
hardy legumes which would survive Alaska winters
and produce satisfactory yields of high quality
forage. To meet this need hundreds of legume
species and strains have been introduced during
the past 40 or more years. Almost all have lacked
the necessary hardiness or have not been satisfactory
agronomically. The release of Alaskland
red clover in the spring of 1953 is the first time
a hardy legume has been made available to
growers in Alaska.Cooperating with the United States Department of Agriculture, Agricultural Research Administratio
Drosophila as a model system to study nonautonomous mechanisms affecting tumour growth and cell death
The study of cancer has represented a central focus in medical research for over a century. The great complexity and constant evolution of the pathology require the use of multiple research model systems and interdisciplinary approaches. This is necessary in order to achieve a comprehensive understanding into the mechanisms driving disease initiation and progression, to aid the development of appropriate therapies. In recent decades, the fruit fly Drosophila melanogaster and its associated powerful genetic tools have become a very attractive model system to study tumour-intrinsic and non-tumour-derived processes that mediate tumour development in vivo. In this review, we will summarize recent work on Drosophila as a model system to study cancer biology. We will focus on the interactions between tumours and their microenvironment, including extrinsic mechanisms affecting tumour growth and how tumours impact systemic host physiology
Evidence of late Quaternary environmental change in a continental east Antarctic lake from lacustrine sedimentary pigment distributions
A sediment core from Progress Lake, one of the oldest lacustrine sequences in East Antarctica, contains distinct zones dating from a previous interglacial (most likely Marine Isotope Stage 5e, c. 125-115 kyr BP) and the present interglacial (Marine Isotope Stage 1), separated by a transition zone representing when the lake became sub-glacial. Profiles of fossil pigments, determined using high performance liquid chromatography and liquid chromatography-tandem mass spectrometry, show distinct differences in the photoautotrophic community during these two interglacial periods. The first was dominated by algae and purple phototrophic bacteria, with periods of photic zone euxinia indicated by pigments from anoxygenic phototrophic bacteria. Specific chlorophyll a derivatives reveal periods when grazing pressure impacted significantly on the phytoplankton community. The virtual absence of pigments in the transition zone reflects severe restriction of photoautotrophic activity, consistent with the take having become sub-glacial. Retreat of snow and ice in the late Holocene (3345 C-14 yr Bp) allowed establishment of a less diverse primary producer community, restricted to algae and cyanobacteria. Grazers were severely restricted and oxidative transformation was more important than during the previous interglacial. The pigment data provide a unique and detailed insight in to the evolution of the lake ecology over an interglacial-glacial-interglacial transition and strong evidence that the Marine Isotope Stage 5e interglacial in this region of coastal East Antarctica was several degrees warmer than at present
Effect of Photobiomodulation on Vinblastine-Poisoned Murine HERS Cells
Objective: The aim of this study was to investigate the effect of near-infrared (NIR) photobiomodulation on the proliferation and glutathione levels in murine Hertwig\u27s epithelial root sheath (HERS) cells after poisoning with vinblastine. Background: Photobiomodulation has been shown to improve wound healing in a number of animal models. There have been no studies on the effect of photobiomodulation on cancer-related chemotherapy injury to the cells that initiate tooth root growth. Materials and Methods: Control groups consisted of murine HERS cells without vinblastine (VBβ) and cells with vinblastine at 10, 20, and 30βng/mL (VB10, VB20, and VB30). Experimental groups consisted of these same groups with light therapy (VB-L, VB10L, VB20L, and VB30L). The cells were exposed to vinblastine for 1βh. Photobiomodulation consisted of a 75-cm2 gallium-aluminum-arsenide light-emitting diode (LED) array at an energy density of 12.8βJ/cm2, delivered with 50βmW/cm2 power over 256βs. Results: Vinblastine alone significantly decreased HERS cell proliferation and glutathione levels at all concentrations (VB10 [β55%, pβ\u3cβ1.0βΓβ10β8]; VB20 [β72%, pβ\u3cβ1.0βΓβ10β9]; VB30 [β80%, pβ\u3cβ1.0βΓβ10β10]; and VB10 [β36%, pβ\u3cβ0.0001]; VB20 [β49%, pβ\u3cβ1.0βΓβ10β6]; VB30 [β53%, pβ\u3cβ1.0βΓβ10β7] respectively). Photobiomodulation significantly increased cell proliferation at all levels of vinblastine exposure (VB10L [+50%, pβ\u3cβ0.0001]; VB20L [+45%, pβ\u3cβ0.05]; VB30 [+39%, pβ\u3cβ0.05]) but not of the control (+22%, pβ =β0.063). The photobiomodulation significantly increased glutathione production in all concentrations of vinblastine except 20βng/mL (VB10L [+39%, pβ=β0.007]; VB20L [+19%, pβ=β0.087]; VB30 [+14%, pβ=β0.025]) and the control (+12%, pβ=β0.13). Conclusions: Photobiomodulation demonstrated an improvement in proliferation and glutathione levels in vinblastine-poisoned murine HERS cells
Orientational Ordering and Dynamics of Rodlike Polyelectrolytes
The interplay between electrostatic interactions and orientational
correlations is studied for a model system of charged rods positioned on a
chain, using Monte Carlo simulation techniques. It is shown that the coupling
brings about the notion of {\em electrostatic frustration}, which in turn
results in: (i) a rich variety of novel orientational orderings such as chiral
phases, and (ii) an inherently slow dynamics characterized by
stretched-exponential behavior in the relaxation functions of the system.Comment: 7 pages, 10 figure
Intranasal Inhalation of Oxytocin Improves Face Processing in Developmental Prosopagnosia
Developmental prosopagnosia (DP) is characterised by a severe, lifelong impairment in face recognition. Little work has attempted to improve face processing in these individuals, but intriguingly, recent evidence suggests oxytocin can improve face processing in both healthy participants and individuals with autism. This study examined whether oxytocin could also improve face processing in individuals with DP. Ten adults with the condition and 10 matched controls were tested using a randomized placebo-controlled double-blind within-subject experimental design (AB-BA). Each participant took part in two testing sessions where they inhaled 24IU of oxytocin or placebo spray and completed two face processing tests: one assessing face memory and the other face perception. Results showed main effects of both participant group and treatment condition in both face processing tests, but the two did not interact. Specifically, the performance of DP participants was significantly lower than control performance under both oxytocin and placebo conditions, but oxytocin improved processing to a similar extent in both groups
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