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Measuring venous oxygenation using the photoplethysmograph waveform
OBJECTIVE: We investigate the hypothesis that the photoplethysmograph (PPG) waveform can be analyzed to infer regional venous oxygen saturation.
METHODS: Fundamental to the successful isolation of the venous saturation is the identification of PPG characteristics that are unique to the peripheral venous system. Two such characteristics have been identified. First, the peripheral venous waveform tends to reflect atrial contraction. Second, ventilation tends to move venous blood preferentially due to the low pressure and high compliance of the venous system. Red (660 nm) and IR (940 nm) PPG waveforms were collected from 10 cardiac surgery patients using an esophageal PPG probe. These waveforms were analyzed using algorithms written in Mathematica. Four time-domain saturation algorithms (ArtSat, VenSat, ArtInstSat, VenInstSat) and four frequency-domain saturation algorithms (RespDC, RespAC, Cardiac, and Harmonic) were applied to the data set.
RESULTS: Three of the algorithms for calculating venous saturation (VenSat, VenInstSat, and RespDC) demonstrate significant difference from ArtSat (the conventional time-domain algorithm for measuring arterial saturation) using the Wilcoxon signed-rank test with Bonferroni correction (p < 0.0071).
CONCLUSIONS: This work introduces new algorithms for PPG analysis. Three algorithms (VenSat, VenInstSat, and RespDC) succeed in detecting lower saturation blood. The next step is to confirm the accuracy of the measurement by comparing them to a gold standard (i.e., venous blood gas)
In Varietate Concordia—United in Diversity European Parliamentary Debate as an Argumentative Activity Type
Role of inclusive self-help groups in prevention and management of diabetes and hypertension in Myanmar:a qualitative study
Background: Noncommunicable diseases (NCDs) are a growing public health concern in Myanmar. Community-based self-help groups are essential for participating in health-related activities. However, little is known about the role of inclusive self-help groups (ISHG) in hypertension and diabetes management. This study aimed to assess knowledge and perception of health-related activities of ISHG and explore challenges ISHG group members encountered in performing hypertension and diabetes prevention and management activities.Methods: The study included six townships from three different regions of Myanmar, where ISHG existed. Two focus group discussions (FGDs) were held in each township. A total of twelve FGDs were conducted. All discussions were conducted, audio-recorded and transcribed verbatim in Myanmar language. A thematic analysis was performed using inductive and deductive approaches.Results: The findings revealed that ISHG members provided advice and counselling on behavioural risk factors for hypertension and diabetes prevention and screenings for those diseases. They also offered home care for the elderly and stroke patients who required their assistance. Community members regarded ISHG as a valuable community structure. Members of the ISHG identified a number of challenges, including lack of resources (funding, manpower, and time), lack of confidence, and lack of recognition and acceptance. Support and strengthening activities by local authorities and the government were critical to sustain ISHG's activities and efforts.Conclusions: Hypertension and diabetes management activities of ISHG are appreciative. The public and government should recognize and support ISHG to strengthen their community activities
A review of selected research priority setting processes at national level in low and middle income countries: towards fair and legitimate priority setting
<p>Abstract</p> <p>Background</p> <p>It is estimated that more than $130 billion is invested globally into health research each year. Increasingly, there is a need to set priorities in health research investments in a fair and legitimate way, using a sound and transparent methodology. In this paper we review selected priority setting processes at national level in low and middle income countries. We outline a set of criteria to assess the process of research priority setting and use these to describe and evaluate priority setting exercises that have taken place at country level. Based on these insights, recommendations are made regarding the constituents of a good priority setting process.</p> <p>Methods</p> <p>Data were gathered from presentations at a meeting held at the World Health Organization (WHO) in 2008 and a web-based search. Based on this literature review a number of criteria were developed to evaluate the priority setting processes.</p> <p>Results</p> <p>Across the countries surveyed there was a relative lack of genuine stakeholder engagement; countries varied markedly in the extent to which the priority setting processes were documented; none of the countries surveyed had a systematic or operational appeals process for outlined priorities; and in all countries (except South Africa) the priorities that were outlined described broad disease categories rather than specific research questions.</p> <p>Conclusions</p> <p>Country level priority setting processes differed significantly in terms of the methods used. We argue that priority setting processes must have in-built mechanisms for publicizing results, effective procedures to enforce decisions as well as processes to ensure that the revision of priorities happens in practice.</p
Direct Measurement of Nuclear Dependence of Charged Current Quasielastic-like Neutrino Interactions using MINERvA
Charged-current interactions on carbon, iron, and lead with a
final state hadronic system of one or more protons with zero mesons are used to
investigate the influence of the nuclear environment on quasielastic-like
interactions. The transfered four-momentum squared to the target nucleus,
, is reconstructed based on the kinematics of the leading proton, and
differential cross sections versus and the cross-section ratios of iron,
lead and carbon to scintillator are measured for the first time in a single
experiment. The measurements show a dependence on atomic number. While the
quasielastic-like scattering on carbon is compatible with predictions, the
trends exhibited by scattering on iron and lead favor a prediction with
intranuclear rescattering of hadrons accounted for by a conventional particle
cascade treatment. These measurements help discriminate between different
models of both initial state nucleons and final state interactions used in the
neutrino oscillation experiments
Altered DNA methylation associated with a translocation linked to major mental illness
Recent work has highlighted a possible role for altered epigenetic modifications, including differential DNA methylation, in susceptibility to psychiatric illness. Here, we investigate blood-based DNA methylation in a large family where a balanced translocation between chromosomes 1 and 11 shows genome-wide significant linkage to psychiatric illness. Genome-wide DNA methylation was profiled in whole-blood-derived DNA from 41 individuals using the Infinium HumanMethylation450 BeadChip (Illumina Inc., San Diego, CA). We found significant differences in DNA methylation when translocation carriers (n = 17) were compared to related non-carriers (n = 24) at 13 loci. All but one of the 13 significant differentially methylated positions (DMPs) mapped to the regions surrounding the translocation breakpoints. Methylation levels of five DMPs were associated with genotype at SNPs in linkage disequilibrium with the translocation. Two of the five genes harbouring significant DMPs, DISC1 and DUSP10, have been previously shown to be differentially methylated in schizophrenia. Gene Ontology analysis revealed enrichment for terms relating to neuronal function and neurodevelopment among the genes harbouring the most significant DMPs. Differentially methylated region (DMR) analysis highlighted a number of genes from the MHC region, which has been implicated in psychiatric illness previously through genetic studies. We show that inheritance of a translocation linked to major mental illness is associated with differential DNA methylation at loci implicated in neuronal development/function and in psychiatric illness. As genomic rearrangements are over-represented in individuals with psychiatric illness, such analyses may be valuable more widely in the study of these conditions
Data Stream Clustering for Real-Time Anomaly Detection: An Application to Insider Threats
Insider threat detection is an emergent concern for academia, industries, and governments due to the growing number of insider incidents in recent years. The continuous streaming of unbounded data coming from various sources in an organisation, typically in a high velocity, leads to a typical Big Data computational problem. The malicious insider threat refers to anomalous behaviour(s) (outliers) that deviate from the normal baseline of a data stream. The absence of previously logged activities executed by users shapes the insider threat detection mechanism into an unsupervised anomaly detection approach over a data stream. A common shortcoming in the existing data mining approaches to detect insider threats is the high number of false alarms/positives (FPs). To handle the Big Data issue and to address the shortcoming, we propose a streaming anomaly detection approach, namely Ensemble of Random subspace Anomaly detectors In Data Streams (E-RAIDS), for insider threat detection. E-RAIDS learns an ensemble of p established outlier detection techniques [Micro-cluster-based Continuous Outlier Detection (MCOD) or Anytime Outlier Detection (AnyOut)] which employ clustering over continuous data streams. Each model of the p models learns from a random feature subspace to detect local outliers, which might not be detected over the whole feature space. E-RAIDS introduces an aggregate component that combines the results from the p feature subspaces, in order to confirm whether to generate an alarm at each window iteration. The merit of E-RAIDS is that it defines a survival factor and a vote factor to address the shortcoming of high number of FPs. Experiments on E-RAIDS-MCOD and E-RAIDS-AnyOut are carried out, on synthetic data sets including malicious insider threat scenarios generated at Carnegie Mellon University, to test the effectiveness of voting feature subspaces, and the capability to detect (more than one)-behaviour-all-threat in real-time. The results show that E-RAIDS-MCOD reports the highest F1 measure and less number of false alarm = 0 compared to E-RAIDS-AnyOut, as well as it attains to detect approximately all the insider threats in real-time
IL-10 Suppression of NK/DC Crosstalk Leads to Poor Priming of MCMV-Specific CD4 T Cells and Prolonged MCMV Persistence
IL-10 is an anti-inflammatory cytokine that regulates the extent of host immunity to infection by exerting suppressive effects on different cell types. Herpes viruses induce IL-10 to modulate the virus-host balance towards their own benefit, resulting in prolonged virus persistence. To define the cellular and molecular players involved in IL-10 modulation of herpes virus-specific immunity, we studied mouse cytomegalovirus (MCMV) infection. Here we demonstrate that IL-10 specifically curtails the MCMV-specific CD4 T cell response by suppressing the bidirectional crosstalk between NK cells and myeloid dendritic cells (DCs). In absence of IL-10, NK cells licensed DCs to effectively prime MCMV-specific CD4 T cells and we defined the pro-inflammatory cytokines IL-12, IFN-γ and TNF-α as well as NK cell activating receptors NKG2D and NCR-1 to regulate this bidirectional NK/DC interplay. Consequently, markedly enhanced priming of MCMV-specific CD4 T cells in Il10-/-mice led to faster control of lytic viral replication, bu
A Preclinical Assessment of Neural Stem Cells as Delivery Vehicles for Anti-Amyloid Therapeutics
Transplantation of neural stems cells (NSCs) could be a useful means to deliver biologic therapeutics for late-stage Alzheimer's disease (AD). In this study, we conducted a small preclinical investigation of whether NSCs could be modified to express metalloproteinase 9 (MMP9), a secreted protease reported to degrade aggregated Aβ peptides that are the major constituents of the senile plaques. Our findings illuminated three issues with using NSCs as delivery vehicles for this particular application. First, transplanted NSCs generally failed to migrate to amyloid plaques, instead tending to colonize white matter tracts. Second, the final destination of these cells was highly influenced by how they were delivered. We found that our injection methods led to cells largely distributing to white matter tracts, which are anisotropic conduits for fluids that facilitate rapid distribution within the CNS. Third, with regard to MMP9 as a therapeutic to remove senile plaques, we observed high concentrations of endogenous metalloproteinases around amyloid plaques in the mouse models used for these preclinical tests with no evidence that the NSC-delivered enzymes elevated these activities or had any impact. Interestingly, MMP9-expressing NSCs formed substantially larger grafts. Overall, we observed long-term survival of NSCs in the brains of mice with high amyloid burden. Therefore, we conclude that such cells may have potential in therapeutic applications in AD but improved targeting of these cells to disease-specific lesions may be required to enhance efficacy
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