654 research outputs found
Multi-Layer Cyber-Physical Security and Resilience for Smart Grid
The smart grid is a large-scale complex system that integrates communication
technologies with the physical layer operation of the energy systems. Security
and resilience mechanisms by design are important to provide guarantee
operations for the system. This chapter provides a layered perspective of the
smart grid security and discusses game and decision theory as a tool to model
the interactions among system components and the interaction between attackers
and the system. We discuss game-theoretic applications and challenges in the
design of cross-layer robust and resilient controller, secure network routing
protocol at the data communication and networking layers, and the challenges of
the information security at the management layer of the grid. The chapter will
discuss the future directions of using game-theoretic tools in addressing
multi-layer security issues in the smart grid.Comment: 16 page
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Effectiveness of UK optometric enhanced eye care services: a realist review of the literature
PURPOSE: UK demographic and legislative changes combined with increasing burdens on National Health Service manpower and budgets have led to extended roles for community optometrists providing locally-commissioned enhanced optometric services (EOS). This realist review's objectives were to develop programme theories that implicitly or explicitly explain quality outcomes for eye care provided by optometrists via EOS and to test these theories by investigating the effectiveness of services for cataract, glaucoma, and primary eye care.
METHODS: The review protocol was published on PROSPERO, and RAMESES publication standards were followed. Programme theories were formulated via scoping literature searches and expert consultation. The searching process involved all relevant electronic databases and grey literature, without restrictions on study design. Data synthesis focussed on questioning the integrity of each theory by considering supportive and refuting evidence from the source literature.
RESULTS: Good evidence exists for cataract, glaucoma and primary eye care EOS that: with appropriate training, accredited optometrists manage patients commensurate with usual care standards; genuine partnerships can exist between community and hospital providers for cataract and glaucoma EOS; patient satisfaction with all three types of service is high; cost-effectiveness of services is unproven for cataract and primary eye care, while glaucoma EOS cost-effectiveness depends on service type; contextual factors may influence service success.
CONCLUSIONS: The EOS reviewed are clinically effective and provide patient satisfaction but limited data is available on cost-effectiveness
Conjugated bile acids attenuate allergen-induced airway inflammation and hyperresposiveness by inhibiting UPR transducers
© 2019 American Society for Clinical Investigation. Conjugated bile acids (CBAs), such as tauroursodeoxycholic acid (TUDCA), are known to resolve the inflammatory and unfolded protein response (UPR) in inflammatory diseases, such as asthma. Whether CBAs exert their beneficial effects on allergic airway responses via 1 arm or several arms of the UPR, or alternatively through the signaling pathways for conserved bile acid receptor, remains largely unknown. We used a house dust mite-induced (HDM-induced) murine model of asthma to evaluate and compare the effects of 5 CBAs and 1 unconjugated bile acid in attenuating allergen-induced UPR and airway responses. Expression of UPRassociated transcripts was assessed in airway brushings from human patients with asthma and healthy subjects. Here we show that CBAs, such as alanyl β-muricholic acid (AβM) and TUDCA, significantly decreased inflammatory, immune, and cytokine responses; mucus metaplasia; and airway hyperresponsiveness, as compared with other CBAs in a model of allergic airway disease. CBAs predominantly bind to activating transcription factor 6α (ATF6α) compared with the other canonical transducers of the UPR, subsequently decreasing allergen-induced UPR activation and resolving allergic airway disease, without significant activation of the bile acid receptors. TUDCA and AβM also attenuated other HDM-induced ER stress markers in the lungs of allergic mice. Quantitative mRNA analysis of airway epithelial brushings from human subjects demonstrated that several ATF6α-related transcripts were significantly upregulated in patients with asthma compared with healthy subjects. Collectively, these results demonstrate that CBA-based therapy potently inhibits the allergen-induced UPR and allergic airway disease in mice via preferential binding of the canonical transducer of the UPR, ATF6α. These results potentially suggest a novel avenue to treat allergic asthma using select CBAs
Systematic review of communication technologies to promote access and engagement of young people with diabetes into healthcare
Background: Research has investigated whether communication technologies (e.g. mobile telephony, forums,
email) can be used to transfer digital information between healthcare professionals and young people who live
with diabetes. The systematic review evaluates the effectiveness and impact of these technologies on
communication.
Methods: Nine electronic databases were searched. Technologies were described and a narrative synthesis of all
studies was undertaken.
Results: Of 20,925 publications identified, 19 met the inclusion criteria, with 18 technologies assessed. Five
categories of communication technologies were identified: video-and tele-conferencing (n = 2); mobile telephony
(n = 3); telephone support (n = 3); novel electronic communication devices for transferring clinical information (n =
10); and web-based discussion boards (n = 1). Ten studies showed a positive improvement in HbA1c following the
intervention with four studies reporting detrimental increases in HbA1c levels. In fifteen studies communication
technologies increased the frequency of contact between patient and healthcare professional. Findings were
inconsistent of an association between improvements in HbA1c and increased contact. Limited evidence was
available concerning behavioural and care coordination outcomes, although improvement in quality of life, patientcaregiver
interaction, self-care and metabolic transmission were reported for some communication technologies.
Conclusions: The breadth of study design and types of technologies reported make the magnitude of benefit and
their effects on health difficult to determine. While communication technologies may increase the frequency of
contact between patient and health care professional, it remains unclear whether this results in improved
outcomes and is often the basis of the intervention itself. Further research is needed to explore the effectiveness
and cost effectiveness of increasing the use of communication technologies between young people and
healthcare professionals
Taking stock: provider prescribing practices in the presence and absence of ACT stock
BACKGROUND: Globally, the monitoring of prompt and effective treatment for malaria with artemisinin combination therapy (ACT) is conducted largely through household surveys. This measure; however, provides no information on case management processes at the health facility level. The aim of this review was to assess evidence from health facility surveys on malaria prescribing practices using ACT, in the presence and absence of ACT stock, at time and place where treatment was sought. METHODS: A systematic search of published literature was conducted. Findings were collated and data extracted on proportion of patients prescribed ACT and alternative anti-malarials in the presence and absence of ACT stock. RESULTS: Of the 14 studies identified in which ACT prescription for uncomplicated malaria in the public sector was evaluated, just six, from three countries (Kenya, Uganda and Zambia), reported this in the context of ACT stock. Comparing facilities with ACT stock to facilities without stock (i) ACT prescribing was significantly higher in all six studies, increasing by a range of 21.3% in children < 5 yrs weighing ≥ 5 kg (p < 0.001; Kenya 2006) to 51.7% in children ≥ 10 kg (p < 0.001; Zambia 2006); (ii) SP prescribing decreased significantly in five studies, by a range of 14.4% (p < 0.001; Kenya 2006), to 46.3% (p < 0.001; Zambia 2006); (iii) Where quinine was a reported alternative, prescriptions decreased in five of the six studies by 0.1% (p = 1.0, Kenya 2010) to 10.2% (p < 0.001; Zambia 2006). At facilities with no ACT stock on the survey day, the proportion of febrile patients prescribed ACT was < 10% in five of the nine target groups included in the six studies, with the proportion prescribed ACT ranging from 0 to 28.4% (Uganda 2007). CONCLUSIONS: Prescriber practices vary based on ACT availability. Although ACT prescriptions increased and alternative anti-malarials prescriptions decreased in the presence of ACT stock, ACT was prescribed in the absence, and alternative anti-malarials were prescribed in the presence of, ACT. Presence of stock alone does not ensure that treatment guidelines are followed. More health facility surveys, together with qualitative research, are needed to understand the role of ACT stock-outs on provider prescribing behaviours and preferences
Systematic review and meta-analysis of the diagnostic accuracy of ultrasonography for deep vein thrombosis
Background
Ultrasound (US) has largely replaced contrast venography as the definitive diagnostic test for deep vein thrombosis (DVT). We aimed to derive a definitive estimate of the diagnostic accuracy of US for clinically suspected DVT and identify study-level factors that might predict accuracy.
Methods
We undertook a systematic review, meta-analysis and meta-regression of diagnostic cohort studies that compared US to contrast venography in patients with suspected DVT. We searched Medline, EMBASE, CINAHL, Web of Science, Cochrane Database of Systematic Reviews, Cochrane Controlled Trials Register, Database of Reviews of Effectiveness, the ACP Journal Club, and citation lists (1966 to April 2004). Random effects meta-analysis was used to derive pooled estimates of sensitivity and specificity. Random effects meta-regression was used to identify study-level covariates that predicted diagnostic performance.
Results
We identified 100 cohorts comparing US to venography in patients with suspected DVT. Overall sensitivity for proximal DVT (95% confidence interval) was 94.2% (93.2 to 95.0), for distal DVT was 63.5% (59.8 to 67.0), and specificity was 93.8% (93.1 to 94.4). Duplex US had pooled sensitivity of 96.5% (95.1 to 97.6) for proximal DVT, 71.2% (64.6 to 77.2) for distal DVT and specificity of 94.0% (92.8 to 95.1). Triplex US had pooled sensitivity of 96.4% (94.4 to 97.1%) for proximal DVT, 75.2% (67.7 to 81.6) for distal DVT and specificity of 94.3% (92.5 to 95.8). Compression US alone had pooled sensitivity of 93.8 % (92.0 to 95.3%) for proximal DVT, 56.8% (49.0 to 66.4) for distal DVT and specificity of 97.8% (97.0 to 98.4). Sensitivity was higher in more recently published studies and in cohorts with higher prevalence of DVT and more proximal DVT, and was lower in cohorts that reported interpretation by a radiologist. Specificity was higher in cohorts that excluded patients with previous DVT. No studies were identified that compared repeat US to venography in all patients. Repeat US appears to have a positive yield of 1.3%, with 89% of these being confirmed by venography.
Conclusion
Combined colour-doppler US techniques have optimal sensitivity, while compression US has optimal specificity for DVT. However, all estimates are subject to substantial unexplained heterogeneity. The role of repeat scanning is very uncertain and based upon limited data
Search for Gravitational Waves from Primordial Black Hole Binary Coalescences in the Galactic Halo
We use data from the second science run of the LIGO gravitational-wave
detectors to search for the gravitational waves from primordial black hole
(PBH) binary coalescence with component masses in the range 0.2--.
The analysis requires a signal to be found in the data from both LIGO
observatories, according to a set of coincidence criteria. No inspiral signals
were found. Assuming a spherical halo with core radius 5 kpc extending to 50
kpc containing non-spinning black holes with masses in the range 0.2--, we place an observational upper limit on the rate of PBH coalescence
of 63 per year per Milky Way halo (MWH) with 90% confidence.Comment: 7 pages, 4 figures, to be submitted to Phys. Rev.
Patient-derived mutations within the N-terminal domains of p85α impact PTEN or Rab5 binding and regulation
The p85α protein regulates flux through the PI3K/PTEN signaling pathway, and also controls receptor trafficking via regulation of Rab-family GTPases. In this report, we determined the impact of several cancer patient-derived p85α mutations located within the N-terminal domains of p85α previously shown to bind PTEN and Rab5, and regulate their respective functions. One p85α mutation, L30F, significantly reduced the steady state binding to PTEN, yet enhanced the stimulation of PTEN lipid phosphatase activity. Three other p85α mutations (E137K, K288Q, E297K) also altered the regulation of PTEN catalytic activity. In contrast, many p85α mutations reduced the binding to Rab5 (L30F, I69L, I82F, I177N, E217K), and several impacted the GAP activity of p85α towards Rab5 (E137K, I177N, E217K, E297K). We determined the crystal structure of several of these p85α BH domain mutants (E137K, E217K, R262T E297K) for bovine p85α BH and found that the mutations did not alter the overall domain structure. Thus, several p85α mutations found in human cancers may deregulate PTEN and/or Rab5 regulated pathways to contribute to oncogenesis. We also engineered several experimental mutations within the p85α BH domain and identified L191 and V263 as important for both binding and regulation of Rab5 activit
Cyclin-dependent kinase 5 mediates pleiotrophin-induced endothelial cell migration
Pleiotrophin (PTN) stimulates endothelial cell migration through binding to receptor protein tyrosine phosphatase beta/zeta (RPTPβ/ζ) and ανβ3 integrin. Screening for proteins that interact with RPTPβ/ζ and potentially regulate PTN signaling, through mass spectrometry analysis, identified cyclin-dependent kinase 5 (CDK5) activator p35 among the proteins displaying high sequence coverage. Interaction of p35 with the serine/threonine kinase CDK5 leads to CDK5 activation, known to be implicated in cell migration. Protein immunoprecipitation and proximity ligation assays verified p35-RPTPβ/ζ interaction and revealed the molecular association of CDK5 and RPTPβ/ζ. In endothelial cells, PTN activates CDK5 in an RPTPβ/ζ- and phosphoinositide 3-kinase (PI3K)-dependent manner. On the other hand, c-Src, ανβ3 and ERK1/2 do not mediate the PTN-induced CDK5 activation. Pharmacological and genetic inhibition of CDK5 abolished PTN-induced endothelial cell migration, suggesting that CDK5 mediates PTN stimulatory effect. A new pyrrolo[2,3-α]carbazole derivative previously identified as a CDK1 inhibitor, was found to suppress CDK5 activity and eliminate PTN stimulatory effect on cell migration, warranting its further evaluation as a new CDK5 inhibitor. Collectively, our data reveal that CDK5 is activated by PTN, in an RPTPβ/ζ-dependent manner, regulates PTN-induced cell migration and is an attractive target for the inhibition of PTN pro-angiogenic properties
Launching a Novel Preclinical Infrastructure: Comparative Oncology Trials Consortium Directed Therapeutic Targeting of TNFα to Cancer Vasculature
Background: Under the direction and sponsorship of the National Cancer Institute, we report on the first pre-clinical trial of the Comparative Oncology Trials Consortium (COTC). The COTC is a novel infrastructure to integrate cancers that naturally develop in pet dogs into the development path of new human drugs. Trials are designed to address questions challenging in conventional preclinical models and early phase human trials. Large animal spontaneous cancer models can be a valuable addition to successful studies of cancer biology and novel therapeutic drug, imaging and device development. Methodology/Principal Findings: Through this established infrastructure, the first trial of the COTC (COTC001) evaluated a targeted AAV-phage vector delivering tumor necrosis factor (RGD-A-TNF) to αV integrins on tumor endothelium. Trial progress and data was reviewed contemporaneously using a web-enabled electronic reporting system developed for the consortium. Dose-escalation in cohorts of 3 dogs (n = 24) determined an optimal safe dose (5 x 1012 transducing units intravenous) of RGD-A-TNF. This demonstrated selective targeting of tumor-associated vasculature and sparing of normal tissues assessed via serial biopsy of both tumor and normal tissue. Repetitive dosing in a cohort of 14 dogs, at the defined optimal dose, was well tolerated and led to objective tumor regression in two dogs (14%), stable disease in six (43%), and disease progression in six (43%) via Response Evaluation Criteria in Solid Tumors (RECIST). Conclusions/Significance: The first study of the COTC has demonstrated the utility and efficiency of the established infrastructure to inform the development of new cancer drugs within large animal naturally occurring cancer models. The preclinical evaluation of RGD-A-TNF within this network provided valuable and necessary data to complete the design of first-in-man studies
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