4,353 research outputs found
Lessons Learned from a Review of 50 ASR Projects from the United States, England, Australia, India, and Africa
The University of Florida has conducted a significant research program over the last four years investigating various aspects of Aquifer, Storage and Recovery (ASR). One pillar of this research effort was the compilation of ASR field data from around the world. Data and supporting information was compiled for over 50 ASR sites located in the United States, England, Australia, India, and Africa. This field data review was completed with two main objectives. First, the ASR operating data was reviewed to evaluate operational similarities and differences. Second, the ASR field data was reviewed to identify fatal flaws that could be avoided at future ASR projects or lessons learned that could aid existing and future ASR projects. Summary tables were prepared comparing basic site information, such as geologic environment or aquifer transmissivity, and site operational characteristics, such as recharge water quality and geochemical issues. Data from 50 of the ASR sites are reviewed in this article. The data revealed that a majority of the sites have been successful in meeting their project goals and objectives; however, a few of the sites have had considerable problems that have limited their overall feasibility
A large-scale simulation of the piriform cortex by a cell automaton-based network model
An event-driven framework is used to construct physiologically motivated large-scale model of the piriform cortex containing in the order of 105 neuron-like computing units. This approach is based on a hierarchically defined highly abstract neuron model consisting of finite-state machines. It provides computational efficiency while incorporating components which have identifiable counterparts in the neurophysiological domain. The network model incorporates four neuron types, and glutamatergic excitatory and inhibitory synapses. The spatio-temporal patterns of cortical activity and the temporal and spectral characteristics of simulated electroencephalograms (EEGs) are studied. In line with previous experimental and compartmental work, 1) shock stimuli elicit EEG profiles with either isolated peaks or damped oscillations, the response type being determined by the intensity of the stimuli, and 2) temporally unpatterned input generates EEG oscillations supported by model-wide waves of excitation. <br/
The application of metacommunity theory to the management of riverine ecosystems
River managers strive to use the best available science to sustain biodi versity and ecosystem function. T o achieve this goal requires consideration of processes at different scales. Metacommunity theory describes how multiple species from differ- ent communities potentially interact with local-scale environmental drivers to influ- ence population dynamics and community structure. However, this body of knowledge has only rarely been used to inform management practices for river ecosystems. In this article, we present a conceptual model outlining how the metacommunity processes of local niche sorting and dispersal can influence the outcomes of management interventions and provide a series of specific recommen- dations for applying these ideas as well as research needs. In all cases, we identify situations where traditional approaches to riverine management could be enhanced by incorporating an understanding of metacommunity dynamics. A common theme is developing guidelines for assessing the metacommunity context of a site or region, evaluating how that context may affect the desired outcome, and incorporat- ing that understanding into the planning process and methods used. To maximize the effectiveness of management activities, scientists, and resource managers should update the toolbox of approaches to riverine management to reflect theoretical advances in metacommunity ecology
Management of bone metastasis and cancer treatment-induced bone loss during the COVID-19 pandemic: An international perspective and recommendations
Optimum management of patients with cancer during the COVID-19 pandemic has proved extremely challenging. Patients, clinicians and hospital authorities have had to balance the risks to patients of attending hospital, many of whom are especially vulnerable, with the risks of delaying or modifying cancer treatment. Those whose care has been significantly impacted include patients suffering from the effects of cancer on bone, where delivering the usual standard of care for bone support has often not been possible and clinicians have been forced to seek alternative options for adequate management. At a virtual meeting of the Cancer and Bone Society in July 2020, an expert group shared experiences and solutions to this challenge, following which a questionnaire was sent internationally to the symposium\u27s participants, to explore the issues faced and solutions offered. 70 respondents, from 9 countries (majority USA, 39%, followed by UK, 19%) included 50 clinicians, spread across a diverse range of specialties (but with a high proportion, 64%, of medical oncologists) and 20 who classified themselves as non-clinical (solely lab-based). Spread of clinician specialty across tumour types was breast (65%), prostate (27%), followed by renal, myeloma and melanoma. Analysis showed that management of metastatic bone disease in all solid tumour types and myeloma, adjuvant bisphosphonate breast cancer therapy and cancer treatment induced bone loss, was substantially impacted. Respondents reported delays to routine CT scans (58%), standard bone scans (48%) and MRI scans (46%), though emergency scans were less affected. Delays in palliative radiotherapy for bone pain were reported by 31% of respondents with treatments often involving only a single dose without fractionation. Delays to, or cancellation of, prophylactic surgery for bone pain were reported by 35% of respondents. Access to treatments with intravenous bisphosphonates and subcutaneous denosumab was a major problem, mitigated by provision of drug administration at home or in a local clinic, reduced frequency of administration or switching to oral bisphosphonates taken at home. The questionnaire also revealed damaging delays or complete stopping of both clinical and laboratory research. In addition to an analysis of the questionnaire, this paper presents a rationale and recommendations for adaptation of the normal guidelines for protection of bone health during the pandemic
The effect of the COVID-19 pandemic on hip and knee arthroplasty patients in the United States: A multicenter update to the previous survey
Background: In March 2020, elective total hip and knee arthroplasty (THA and TKA) were suspended across the United States in response to the COVID-19 pandemic. We had previously published the results of a survey to the affected patients from 6 institutions. We now present the results of a larger distribution of this survey, through May and June 2020, to electively scheduled patients representing different regions of the United States.
Methods: Fifteen centers identified through the American Association of Hip and Knee Surgeons Research Committee participated in a survey study of THA and TKA patients. Patients scheduled for primary elective THA or TKA but canceled due to the COVID-19 elective surgery stoppage (3/2020-5/2020) were included in the study. Descriptive statistics along with subgroup analysis with Wilcoxon rank were performed.
Results: In total, surveys were distributed to 2135 patients and completed by 848 patients (40%) from 15 institutions. Most patients (728/848, 86%) had their surgery postponed or canceled by the surgeon or hospital. Unknown length of surgical delay remained the highest source of anxiety among survey participants. Male patients were more likely to be willing to proceed with surgery in spite of COVID-19. There were minimal regional differences in responses. Only 61 patients (7%) stated they will continue to delay surgery for fear of contracting COVID-19 while in the hospital.
Conclusion: Similar to the previous study, the most anxiety-provoking thought was the uncertainty, over if and when the canceled joint replacement surgery could be rescheduled. Patients suffering from the daily pain of hip and knee arthritis who have been scheduled for elective arthroplasty remain eager to have their operation as soon as elective surgery is allowed to resume
GLP-1R agonists demonstrate potential to treat Wolfram syndrome in human preclinical models
AIMS/HYPOTHESIS: Wolfram syndrome is a rare autosomal recessive disorder caused by pathogenic variants in the WFS1 gene. It is characterised by insulin-dependent diabetes mellitus, optic nerve atrophy, diabetes insipidus, hearing loss and neurodegeneration. Considering the unmet treatment need for this orphan disease, this study aimed to evaluate the therapeutic potential of glucagon-like peptide 1 receptor (GLP-1R) agonists under wolframin (WFS1) deficiency with a particular focus on human beta cells and neurons.
METHODS: The effect of the GLP-1R agonists dulaglutide and exenatide was examined in Wfs1 knockout mice and in an array of human preclinical models of Wolfram syndrome, including WFS1-deficient human beta cells, human induced pluripotent stem cell (iPSC)-derived beta-like cells and neurons from control individuals and individuals affected by Wolfram syndrome, and humanised mice.
RESULTS: Our study shows that the long-lasting GLP-1R agonist dulaglutide reverses impaired glucose tolerance in WFS1-deficient mice, and that exenatide and dulaglutide improve beta cell function and prevent apoptosis in different human WFS1-deficient models including iPSC-derived beta cells from people with Wolfram syndrome. Exenatide improved mitochondrial function, reduced oxidative stress and prevented apoptosis in Wolfram syndrome iPSC-derived neural precursors and cerebellar neurons.
CONCLUSIONS/INTERPRETATION: Our study provides novel evidence for the beneficial effect of GLP-1R agonists on WFS1-deficient human pancreatic beta cells and neurons, suggesting that these drugs may be considered as a treatment for individuals with Wolfram syndrome
Extracting the Groupwise Core Structural Connectivity Network: Bridging Statistical and Graph-Theoretical Approaches
Finding the common structural brain connectivity network for a given
population is an open problem, crucial for current neuro-science. Recent
evidence suggests there's a tightly connected network shared between humans.
Obtaining this network will, among many advantages , allow us to focus
cognitive and clinical analyses on common connections, thus increasing their
statistical power. In turn, knowledge about the common network will facilitate
novel analyses to understand the structure-function relationship in the brain.
In this work, we present a new algorithm for computing the core structural
connectivity network of a subject sample combining graph theory and statistics.
Our algorithm works in accordance with novel evidence on brain topology. We
analyze the problem theoretically and prove its complexity. Using 309 subjects,
we show its advantages when used as a feature selection for connectivity
analysis on populations, outperforming the current approaches
Remarks on identical particles in de Broglie-Bohm theory
It is argued that the topological approach to the (anti-)symmetrisation
condition for the quantum state of a collection of identical particles, defined
in the `reduced' configuration space, is particularly natural from the
perspective of de Broglie-Bohm pilot-wave theory.Comment: RevTeX, 9 pp., to appear in Physics Letters
Proactive prevention: Act now to disrupt the impending non-communicable disease crisis in low-burden populations
Non-communicable disease (NCD) prevention efforts have traditionally targeted high-risk and high-burden populations. We propose an alteration in prevention efforts to also include emphasis and focus on low-risk populations, predominantly younger individuals and low-prevalence populations. We refer to this approach as proactive prevention. This emphasis is based on the priority to put in place policies, programs, and infrastructure that can disrupt the epidemiological transition to develop NCDs among these groups, thereby averting future NCD crises. Proactive prevention strategies can be classified, and their implementation prioritized, based on a 2-dimensional assessment: impact and feasibility. Thus, potential interventions can be categorized into a 2-by-2 matrix: high impact/high feasibility, high impact/low feasibility, low impact/high feasibility, and low impact/low feasibility. We propose that high impact/high feasibility interventions are ready to be implemented (act), while high impact/low feasibility interventions require efforts to foster buy-in first. Low impact/high feasibility interventions need to be changed to improve their impact while low impact/low feasibility might be best re-designed in the context of limited resources. Using this framework, policy makers, public health experts, and other stakeholders can more effectively prioritize and leverage limited resources in an effort to slow or prevent the evolving global NCD crisis
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