933 research outputs found
Internal iamin structures within G1 nuclei of human dermal fibroblasts
The nuclear lamina is a mesh-like network of fibres subjacent
to the inner nuclear membrane that is believed
to be involved in the specific spatial reorganisation of
chromatin after mitosis. To determine how the lamina
might be involved in chromatin reorganisation, we have
performed indirect immunofluorescence studies on quiescent
and proliferating human dermal fibroblasts
(HDF). Two monoclonal antibodies recognising human
lamins A and C and three different fixation methods
were employed. In indirect immunofluorescence studies,
cultures of quiescent cells displayed a uniform perinuclear
distribution of the antibodies. In proliferating cultures
two distinct populations of cells were observed:
one population displayed a typical perinuclear antibody
distribution, while the second population displayed an
unusual pattern consisting of a series of spots and fibres
within the nucleus. By inducing cell-cycle synchrony in
cultures we were able to determine that the unusual
internal distribution of the lamin antibodies was
restricted to cells in G1. Optical sectioning and 3-D
reconstruction of the lamina structures in G1 nuclei was
performed with a confocal laser scanning microscope
(CLSM). This revealed that the internal lamin structures
consisted of small foci and fibres proliferating
throughout the nucleus. These structures were shown to
be closely associated with areas of condensed chromatin
but not nuclear membrane. As cells progress towards S
phase the internal lamin foci disappear
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Use of Electric Fish Guidance Technology to Deter Salmonids from Entering Hydro Tailraces and Intake Canals: Two Case Studies
Fermi Surface Reconstruction in CeRhCoIn
The evolution of the Fermi surface of CeRhCoIn was studied as
a function of Co concentration via measurements of the de Haas-van Alphen
effect. By measuring the angular dependence of quantum oscillation frequencies,
we identify a Fermi surface sheet with -electron character which undergoes
an abrupt change in topology as is varied. Surprisingly, this
reconstruction does not occur at the quantum critical concentration ,
where antiferromagnetism is suppressed to T=0. Instead we establish that this
sudden change occurs well below , at the concentration x ~ 0.4 where long
range magnetic order alters its character and superconductivity appears. Across
all concentrations, the cyclotron effective mass of this sheet does not
diverge, suggesting that critical behavior is not exhibited equally on all
parts of the Fermi surface.Comment: 4 pages, 4 figure
Radiation Therapy for Esophageal Cancer
Esophageal cancer develops in the mucosa of the esophagus and spreads toward the muscle layer. The nonsurgical treatment for localized, deeply invasive esophageal cancer has been external beam radiation therapy (EBRT) and concurrent chemotherapy. Recently, intraluminal brachytherapy showed a strong potential for the improvement of the therapeutic ratio. It was found that the fractionated high dose rate (HDR) brachytherapy offered beneficial palliation for a longer period of time with more durable symptom control. A similar was concluded for advanced unresectable esophageal cancer in previously irradiated patients. HDR brachytherapy may be a useful salvage treatment option for inoperable patients diagnosed with local esophageal cancer. Although better local control can be achieved with higher brachytherapy dose, this increases the risk of acute morbidity and late morbidity, especially in the setting of recurrence cancer. It was found that the moderate dose of EBRT and HDR brachytherapy could give a better local response than EBRT alone
{\beta}-YbAlB4: a critical nodal metal
We propose a model for the intrinsic quantum criticality of {\beta}-YbAlB4,
in which a vortex in momentum space gives rise to a new type of Fermi surface
singularity. The unquenched angular momentum of the |J = 7/2,m_J = \pm5/2> Yb
4f-states generates a momentum-space line defect in the hybridization between
4f and conduction electrons, leading to a quasi-two dimensional Fermi surface
with a k\perp4 dispersion and a singular density of states proportional to
E^{-1/2}. We discuss the implications of this line-node in momentum space for
our current understanding of quantum criticality and its interplay with
topology
Do ecosystem service maps and models meet stakeholders’ needs? A preliminary survey across sub-Saharan Africa
To achieve sustainability goals, it is important to incorporate ecosystem service (ES) information into decision-making processes. However, little is known about the correspondence between the needs of ES information users and the data provided by the researcher community. We surveyed stakeholders within sub-Saharan Africa, determining their ES data requirements using a targeted sampling strategy. Of those respondents utilising ES information (>90%; n=60), 27% report having sufficient data; with the remainder requiring additional data – particularly at higher spatial resolutions and at multiple points in time. The majority of respondents focus on provisioning and regulating services, particularly food and fresh water supply (both 58%) and climate regulation (49%). Their focus is generally at national scales or below and in accordance with data availability. Among the stakeholders surveyed, we performed a follow-up assessment for a sub-sample of 17 technical experts. The technical experts are unanimous that ES models must be able to incorporate scenarios, and most agree that ES models should be at least 90% accurate. However, relatively coarse-resolution (1–10 km2) models are sufficient for many services. To maximise the impact of future research, dynamic, multi-scale datasets on ES must be delivered alongside capacity-building efforts
A fine-scale assessment of the ecosystem service-disservice dichotomy in the context of urban ecosystems affected by alien plant invasions
Abstract
Background
Natural resources within and around urban landscapes are under increasing pressure from ongoing urbanisation, and management efforts aimed at ensuring the sustainable provision of ecosystem services (ES) are an important response. Given the limited resources available for assessing urban ES in many cities, practical approaches for integrating ES in decision-making process are needed.
Methods
We apply remote sensing techniques (integrating LiDAR data with high-resolution multispectral imagery) and combined these with supplementary spatial data to develop a replicable approach for assessing the role of urban vegetation (including invasive alien plants) in providing ES and ecosystem disservices (EDS). We identify areas denoting potential management trade-offs based on the spatial distribution of ES and EDS using a local-scale case study in the city of Cape Town, South Africa. Situated within a global biodiversity hotspot, Cape Town must contend with widespread invasions of alien plants (especially trees and shrubs) along with complex socio-political challenges. This represents a useful system to examine the challenges in managing ES and EDS in the context of urban plant invasions.
Results
Areas of high ES provision (for example carbon sequestration, shade and visual amenity) are characterized by the presence of large trees. However, many of these areas also result in numerous EDS due to invasions of alien trees and shrubs – particularly along rivers, in wetlands and along the urban edge where tall alien trees have established and spread into the natural vegetation (for example increased water consumption, increased fire risk and reduced soil quality). This suggests significant trade-offs regarding the management of species and the ES and EDS they provide.
Conclusions
The approach applied here can be used to provide recommendations and to guide city planners and managers to fine-tune management interventions at local scales to maximise the provision of ES
Substance abuse and intimate partner violence: treatment considerations
Given the increased use of marital- and family-based treatments as part of treatment for alcoholism and other drug disorders, providers are increasingly faced with the challenge of addressing intimate partner violence among their patients and their intimate partners. Yet, effective options for clinicians who confront this issue are extremely limited. While the typical response of providers is to refer these cases to some form of batterers' treatment, three fundamental concerns make this strategy problematic: (1) most of the agencies that provide batterers' treatment only accept individuals who are legally mandated to complete their programs; (2) among programs that do accept nonmandated patients, most substance-abusing patients do not accept such referrals or drop out early in the treatment process; and (3) available evidence suggests these programs may not be effective in reducing intimate partner violence. Given these very significant concerns with the current referral approach, coupled with the high incidence of IPV among individuals entering substance abuse treatment, providers need to develop strategies for addressing IPV that can be incorporated and integrated into their base intervention packages
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Examining the Interface Between Substance Misuse and Intimate Partner Violence
There is considerable theoretical and empirical support for a link between substance misuse and perpetration and victimization of intimate partner violence. This review briefly summarizes this literature and highlights current research that addresses the interface between treatment for substance abuse and intimate partner violence. Suggestions for future research and clinical implications are provided
The use of thermographic imaging to evaluate therapeutic response in human tumour xenograft models
YesNon-invasive methods to monitor tumour growth are an important goal in cancer drug development. Thermographic imaging systems offer potential in this area, since a change in temperature is known to be induced due to changes within the tumour microenvironment. This study demonstrates that this imaging modality can be applied to a broad range of tumour xenografts and also, for the first time, the methodology’s suitability to assess anti-cancer agent efficacy. Mice bearing subcutaneously implanted H460 lung cancer xenografts were treated with a novel vascular disrupting agent, ICT-2552, and the cytotoxin doxorubicin. The effects on tumour temperature were assessed using thermographic imaging over the first 6 hours post-administration and subsequently a further 7 days. For ICT-2552 a significant initial temperature drop was observed, whilst for both agents a significant temperature drop was seen compared to controls over the longer time period. Thus thermographic imaging can detect functional differences (manifesting as temperature reductions) in the tumour response to these anti-cancer agents compared to controls. Importantly, these effects can be detected in the first few hours following treatment and therefore the tumour is observable non-invasively. As discussed, this technique will have considerable 3Rs benefits in terms of reduction and refinement of animal use.University of Bradfor
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