1,033 research outputs found
Stressors and threats to the flora of Acadia National Park, Maine: Current knowledge, information gaps, and future directions
Stressors and threats to the flora of Acadia National Park, Maine: Current knowledge, information gaps, and future directions. J. Torrey Bot. Soc. 139: 323â344. 2012.â Acadia National Park is a center of plant diversity in northeastern North America. The Park\u27s varied habitats and flora are sensitive to a number of natural and anthropogenic perturbations. Stressors such as invasive plants, pest and pathogens, ozone, acidic fog and sulfur deposition, nitrogen deposition, heavy metals, fire and fire suppression, over-browsing, visitor use, hurricanes, and climate change have all had effects on the Park\u27s habitats and plant species at some point and it is unclear how many of these stressors are currently affecting the flora of Acadia National Park. We discuss the botanical diversity of Acadia, assess the natural and anthropogenic stressors and threats affecting the Park\u27s flora, and summarize critical information gaps to better assess the known stressors and threats to the flora. Understanding these stressors and threats is critical to making informed management decisions to preserve the botanical diversity of Acadia and other regional parks
A novel role for BRCA1 in regulating breast cancer cell spreading and motility
BRCA1 interacts with ERM proteins at leading edges and focal adhesion sites and modulates motility via its ubiquitin ligase activity
Real Time Global Tests of the ALICE High Level Trigger Data Transport Framework
The High Level Trigger (HLT) system of the ALICE experiment is an online
event filter and trigger system designed for input bandwidths of up to 25 GB/s
at event rates of up to 1 kHz. The system is designed as a scalable PC cluster,
implementing several hundred nodes. The transport of data in the system is
handled by an object-oriented data flow framework operating on the basis of the
publisher-subscriber principle, being designed fully pipelined with lowest
processing overhead and communication latency in the cluster. In this paper, we
report the latest measurements where this framework has been operated on five
different sites over a global north-south link extending more than 10,000 km,
processing a ``real-time'' data flow.Comment: 8 pages 4 figure
Mosquito Magnet Âź traps as a potential means of monitoring blackflies of medical and veterinary importance
Mosquito MagnetÂź traps, deployed in widespread parts of England as part of nationwide mosquito surveillance projects, also caught blackflies. As many as 1242 blackflies were caught in a trapping session lasting 4 days. Principal among the species caught were Simulium equinum, Simulium lineatum and Simulium ornatum s.l. As S. ornatum s.l. is a vector that transmits Onchocerca linealis to cattle and S. equinum is responsible for dermatitis ('sweet itch') in cattle and horses, it is suggested that Mosquito MagnetÂź traps could be used to monitor and partially control these pests, as well as nuisance anthropophilic blackflies such as Simulium posticatum that can cause simuliidosis in southern England
Lake Mead nutrient enhancement project
The Lake Mead Fertilization Project is a research program designed to investigate the potential for using large-scale artificial fertilization to enhance the game fisheries of this reservoir through an increase in the population of threadfin shad, the system\u27s primary forage species. A substantial decline in the population of largemouth bass, together with poor condition of adult striped bass, are the two major issues affecting the Lake Mead game fisheries. Both issues have been hypothesized to be a result of an inadequate amount of forage in the reservoir. Previous studies have in turn suggested that a major factor limiting the shad population may be low productivity levels at the base of the food chain. Approximately 20,000 gallons of liquid ammonium polyphosphate were applied to about 20,000 acres of the Overton Arm in each of the years 1987 through 1989. The fertilizer was applied in late May or early June. Approximately 300 volunteer boats were used to distribute fertilizer in the early stages of the program; these were subsequently replaced with barge applications. A series of stations in both treatment and control areas was intensively sampled to document the impact of fertilization at various levels of the Lake Mead food chain. Fertilizer additions were designed to temporarily increase epilimnetic total phosphorus concentrations by approximately 20 ug/1 and chlorophyll concentrations by 5-10 ug/1. These increases were achieved, although there were substantial horizontal movements of the fertilized water mass, particularly in 1988. Chlorophyll concentrations peaked about 5 days following fertilization and returned to base-line levels within two weeks. Although maximum chlorophyll levels recorded were about 12 ug/1, thirty-day mean concentrations were below 5 ug/l at all stations. Fertilization produced few adverse water quality impacts and all these were short-lived. Water clarity exhibited temporary decreases at some stations in some years. Taste and odor and disinfection by-product formation potentials exhibited weak correlations with chlorophyll concentrations, but the increases were also short-lived. The fertilizer-induced algal production slightly increased the rate at which epilimnetic concentrations of inorganic nitrogen are typically depleted during the growing season in Lake Mead. The phytoplankton community displayed a complex response to fertilization, with some species clearly increasing their abundance and others showing little or no effect. The proportional abundance of blue-greens decreased following the fertilizer additions. Temporal patterns of algal primary production closely followed those of algal biomass. Size-fractionated production measurements demonstrated that most of the production was occurring in the 20-50 Mm size class, and that this pattern remained essentially unchanged as total production levels increased following fertilization. While interesting questions remain concerning the relative importance of resource levels and other factors, for example predation, in determining shad population abundance, fertilization of the Overton Arm, as undertaken during the present study, clearly did not lead to any obvious increase in shad abundance. While a longer-term research program might be able to separate resource-related variance in shad densities from other factors contributing to inter-annual population fluctuations, large-scale artificial fertilization on the scale employed in the present project does not appear to represent a useful management tool for the Lake Mead game fisheries
The STAFF-DWP wave instrument on the DSP equatorial spacecraft: description and first results
The STAFF-DWP wave instrument on board the equatorial spacecraft (TC1) of the Double Star Project consists of a combination of 2 instruments which are a heritage of the Cluster mission: the Spatio-Temporal Analysis of Field Fluctuations (STAFF) experiment and the Digital Wave-Processing experiment (DWP). On DSP-TC1 STAFF consists of a three-axis search coil magnetometer, used to measure magnetic fluctuations at frequencies up to 4 kHz and a waveform unit, up to 10 Hz, plus snapshots up to 180 Hz. DWP provides several onboard analysis tools: a complex FFT to fully characterise electromagnetic waves in the frequency range 10 Hz-4 kHz, a particle correlator linked to the PEACE electron experiment, and compression of the STAFF waveform data. The complementary Cluster and TC1 orbits, together with the similarity of the instruments, permits new multi-point studies. The first results show the capabilities of the experiment, with examples in the different regions of the magnetosphere-solar wind system that have been encountered by DSP-TC1 at the beginning of its operational phase. An overview of the different kinds of electromagnetic waves observed on the dayside from perigee to apogee is given, including the different whistler mode waves (hiss, chorus, lion roars) and broad-band ULF emissions. The polarisation and propagation characteristics of intense waves in the vicinity of a bow shock crossing are analysed using the dedicated PRASSADCO tool, giving results compatible with previous studies: the broad-band ULF waves consist of a superimposition of different wave modes, whereas the magnetosheath lion roars are right-handed and propagate close to the magnetic field. An example of a combined Cluster DSP-TC1 magnetopause crossing is given. This first case study shows that the ULF wave power intensity is higher at low latitude (DSP) than at high latitude (Cluster). On the nightside in the tail, a first wave event comparison - in a rather quiet time interval - is shown. It opens the doors to future studies, such as event timing during substorms, to possibly determine their onset location
Discovery of a single male Aedes aegypti (L.) in Merseyside, England
© The Author(s). 2017. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. The file attached is the published (publishers PDF) version of the article
Expression of caspase-3, p53 and Bcl-2 in generalized aggressive periodontitis
BACKGROUND: Apoptosis, or programmed cell death is a form of physiological cell death. It is increased or decreased in the presence of infection, inflammation or tissue remodelling. Previous studies suggest that apoptosis is involved in the pathogenesis of inflammatory periodontal disease. The aim of the present study was to investigate the clinical features and known indicators of apoptosis (p53, Bcl-2, Caspase-3) in patients with generalized aggressive periodontitis (GAP) METHODS: Eight patients with GAP, who had sites with probing depths (PD) > 5 mm, and 10 periodontally-healthy persons were included in the study. Clinical examinations and PD were performed, and the plaque index and gingival index were recorded. Gingival tissues biopsies were obtained from active site of each patient and from healthy individuals. The expression of caspase-3, Bcl-2, and p53 was evaluated by immunohistochemistry RESULTS: There were no significant differences between GAP and control group with respect to levels of caspase-3 and p53 expression (P > 0.05). Contrary, the frequency of grade 3 expression of Bcl-2 was higher in GAP group than the control group. CONCLUSION: The higher frequency of Bcl-2 expression in GAP group indicates and delayed apoptosis can lead to increasing resident inflammatory cells in periodontal tissues and resulting in progressive periodontal destruction
Isolation and expression of cDNA clones encoding a human receptor for IgG (Fc gamma RII).
Essential versus accessory aspects of cell death: recommendations of the NCCD 2015
Cells exposed to extreme physicochemical or mechanical stimuli die in an uncontrollable manner, as a result of their immediate structural breakdown. Such an unavoidable variant of cellular demise is generally referred to as âaccidental cell deathâ (ACD). In most settings, however, cell death is initiated by a genetically encoded apparatus, correlating with the fact that its course can be altered by pharmacologic or genetic interventions. âRegulated cell deathâ (RCD) can occur as part of physiologic programs or can be activated once adaptive responses to perturbations of the extracellular or intracellular microenvironment fail. The biochemical phenomena that accompany RCD may be harnessed to classify it into a few subtypes, which often (but not always) exhibit stereotyped morphologic features. Nonetheless, efficiently inhibiting the processes that are commonly thought to cause RCD, such as the activation of executioner caspases in the course of apoptosis, does not exert true cytoprotective effects in the mammalian system, but simply alters the kinetics of cellular demise as it shifts its morphologic and biochemical correlates. Conversely, bona fide cytoprotection can be achieved by inhibiting the transduction of lethal signals in the early phases of the process, when adaptive responses are still operational. Thus, the mechanisms that truly execute RCD may be less understood, less inhibitable and perhaps more homogeneous than previously thought. Here, the Nomenclature Committee on Cell Death formulates a set of recommendations to help scientists and researchers to discriminate between essential and accessory aspects of cell death
- âŠ